Kisspeptin papers

pubmed: 2005 and earlier

• Minireview: the neuroendocrine regulation of puberty: is the time ripe for a systems biology approach?
  

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  Minireview: the neuroendocrine regulation of puberty: is the time ripe for a systems biology approach?

  Endocrinology. 2006 Mar;147(3):1166-74

  Authors: Ojeda SR, Lomniczi A, Mastronardi C, Heger S, Roth C, Parent AS, Matagne V, Mungenast AE

  The initiation of mammalian puberty requires an increase in pulsatile release of GnRH from the hypothalamus. This increase is brought about by coordinated changes in transsynaptic and glial-neuronal communication. As the neuronal and glial excitatory inputs to the GnRH neuronal network increase, the transsynaptic inhibitory tone decreases, leading to the pubertal activation of GnRH secretion. The excitatory neuronal systems most prevalently involved in this process use glutamate and the peptide kisspeptin for neurotransmission/neuromodulation, whereas the most important inhibitory inputs are provided by gamma-aminobutyric acid (GABA)ergic and opiatergic neurons. Glial cells, on the other hand, facilitate GnRH secretion via growth factor-dependent cell-cell signaling. Coordination of this regulatory neuronal-glial network may require a hierarchical arrangement. One level of coordination appears to be provided by a host of unrelated genes encoding proteins required for cell-cell communication. A second, but overlapping, level might be provided by a second tier of genes engaged in specific cell functions required for productive cell-cell interaction. A third and higher level of control involves the transcriptional regulation of these subordinate genes by a handful of upper echelon genes that, operating within the different neuronal and glial subsets required for the initiation of the pubertal process, sustain the functional integration of the network. The existence of functionally connected genes controlling the pubertal process is consistent with the concept that puberty is under genetic control and that the genetic underpinnings of both normal and deranged puberty are polygenic rather than specified by a single gene. The availability of improved high-throughput techniques and computational methods for global analysis of mRNAs and proteins will allow us to not only initiate the systematic identification of the different components of this neuroendocrine network but also to define their functional interactions.

  PMID: 16373420 [PubMed - indexed for MEDLINE]

  
  
  
• Minireview: kisspeptin neurons as central processors in the regulation of gonadotropin-releasing hormone secretion.
  

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  Minireview: kisspeptin neurons as central processors in the regulation of gonadotropin-releasing hormone secretion.

  Endocrinology. 2006 Mar;147(3):1154-8

  Authors: Dungan HM, Clifton DK, Steiner RA

  The Kiss1 gene encodes a family of peptides called kisspeptins, which bind to the G protein-coupled receptor GPR54. Kisspeptin(s) and its receptor are expressed in the forebrain, and the discovery that mice and humans lacking a functional GPR54 fail to undergo puberty and exhibit hypogonadotropic hypogonadism implies that kisspeptin signaling plays an essential role in reproduction. Studies in several mammalian species have shown that kisspeptins stimulate the secretion of gonadotropins from the pituitary by stimulating the release of GnRH from the forebrain after the activation of GPR54, which is expressed by GnRH neurons. Kisspeptin is expressed abundantly in the arcuate nucleus (Arc) and the anteroventral periventricular nucleus (AVPV) of the forebrain. Both estradiol and testosterone regulate the expression of the Kiss1 gene in the Arc and AVPV; however, the response of the Kiss1 gene to these steroids is exactly opposite between these two nuclei. Estradiol and testosterone down-regulate Kiss1 mRNA in the Arc and up-regulate its expression in the AVPV. Thus, kisspeptin neurons in the Arc may participate in the negative feedback regulation of gonadotropin secretion, whereas kisspeptin neurons in the AVPV may contribute to generating the preovulatory gonadotropin surge in the female. Hypothalamic levels of Kiss1 and GPR54 mRNA increase dramatically at puberty, suggesting that kisspeptin signaling could mediate the neuroendocrine events that trigger the onset of puberty. Together, these observations demonstrate that kisspeptin-GPR54 signaling in the brain serves as an important conduit for controlling GnRH secretion in the developing and adult animal.

  PMID: 16373418 [PubMed - indexed for MEDLINE]

  
  
  
• Role of metastin in the release of gonadotropin-releasing hormone from the hypothalamus of the male rat.
  

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  Role of metastin in the release of gonadotropin-releasing hormone from the hypothalamus of the male rat.

  J Androl. 2006 May-Jun;27(3):444-9

  Authors: Nazian SJ

  Recent genetic analysis has suggested that the expression of the orphan receptor GPR54 is essential for the onset of puberty in both rodents and humans. Indirect evidence has suggested that this action is via gonadotropin-releasing hormone induction of luteinizing hormone release. The experiments described here were intended to provide direct evidence that metastin, the naturally occurring ligand for GPR54, was capable of stimulating GnRH secretion by examining GnRH release from an immortalized hypothalamic cell line (GT1-7) and from male rat hypothalamic explants. GT1-7 cells were treated for 2(1/2) hours and overnight with the biologically active fragment of metastin, metastin(45-54), in amounts ranging from 0.1 nM to 1 muM. Hypothalamic fragments were obtained from infantile male rats and exposed to progressively increasing concentrations of metastin(45-54) (0.1 nM to 1 muM) for 1-hour periods. In both experiments, GnRH release was measured by radioimmunoassay (RIA). The release of metastin from hypothalami obtained from infantile and adult male rats was also determined. Explants were incubated for 6 hours, and the release of metastin into the media was determined by RIA. The results support the hypothesis that metastin stimulates GnRH secretion from the hypothalamus. The data indicate that an increase in the secretion of metastin, rather than the appearance of the receptor, is required for puberty onset. The results also suggest that metastin influences the GnRH-secreting neurons indirectly via an interneuron rather than acting directly on the GnRH-secreting neurons.

  PMID: 16339453 [PubMed - indexed for MEDLINE]

  
  
  
• Activation of gonadotropin-releasing hormone neurons by kisspeptin as a neuroendocrine switch for the onset of puberty.
  

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  Activation of gonadotropin-releasing hormone neurons by kisspeptin as a neuroendocrine switch for the onset of puberty.

  J Neurosci. 2005 Dec 7;25(49):11349-56

  Authors: Han SK, Gottsch ML, Lee KJ, Popa SM, Smith JT, Jakawich SK, Clifton DK, Steiner RA, Herbison AE

  We examined the role of kisspeptin and its receptor, the G-protein-coupled receptor GPR54, in governing the onset of puberty in the mouse. In the adult male and female mouse, kisspeptin (10-100 nM) evoked a remarkably potent, long-lasting depolarization of >90% of gonadotropin-releasing hormone (GnRH)-green fluorescent protein neurons in situ. In contrast, in juvenile [postnatal day 8 (P8) to P19] and prepubertal (P26-P33) male mice, kisspeptin activated only 27 and 44% of GnRH neurons, respectively. This developmental recruitment of GnRH neurons into a kisspeptin-responsive pool was paralleled by an increase in the ability of centrally administered kisspeptin to evoke luteinizing hormone secretion in vivo. To learn more about the mechanisms through which kisspeptin-GPR54 signaling at the GnRH neuron may change over postnatal development, we performed quantitative in situ hybridization for kisspeptin and GPR54 transcripts. Approximately 90% of GnRH neurons were found to express GPR54 mRNA in both juvenile and adult mice, without a detectable difference in the mRNA content between the age groups. In contrast, the expression of KiSS-1 mRNA increased dramatically across the transition from juvenile to adult life in the anteroventral periventricular nucleus (AVPV; p < 0.001). These results demonstrate that kisspeptin exerts a potent depolarizing effect on the excitability of almost all adult GnRH neurons and that the responsiveness of GnRH neurons to kisspeptin increases over postnatal development. Together, these observations suggest that activation of GnRH neurons by kisspeptin at puberty reflects a dual process involving an increase in kisspeptin input from the AVPV and a post-transcriptional change in GPR54 signaling within the GnRH neuron.

  PMID: 16339030 [PubMed - indexed for MEDLINE]

  
  
  
• We all remember our first kiss: kisspeptin and the male gonadal axis.
  

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  We all remember our first kiss: kisspeptin and the male gonadal axis.

  J Clin Endocrinol Metab. 2005 Dec;90(12):6738-40

  Authors: Seminara SB

  PMID: 16330809 [PubMed - indexed for MEDLINE]

  
  
  
• KiSS-1 expression in human breast cancer.
  

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  KiSS-1 expression in human breast cancer.

  Clin Exp Metastasis. 2005;22(6):503-11

  Authors: Martin TA, Watkins G, Jiang WG

  The KiSS-1 gene encodes a 145 amino acid residue peptide that is further processed to a final peptide, metastin, a ligand to a G-coupled orphan receptor (OT7T175/AXOR12). KiSS-1 has been identified as a putative human metastasis suppressor gene in melanomas and in breast cancer cell lines. This study aimed to determine the expression and distribution of KiSS-1 and its receptor in human breast cancer tissues and to identify a possible link between expression levels and patient prognosis. Frozen sections from breast cancer primary tumours (matched tumour 124 and background 33) were immuno-stained with KiSS-1 antibody. RNA was reverse transcribed and analyzed by Q-PCR (standardized using beta-actin, and normalized with cytokeratin-19 levels). Levels of expression of KiSS-1 were higher in tumour compared to background tissues (3,124+/-1,262 vs 2,397+/-1,181) and significantly increased in node positive tumours compared to node negative (3,637+/-1,719 vs 2,653+/-1,994, P = 0.02). KiSS-1 expression was also increased with increasing grade and TNM status. There were no such trends with the KiSS-1 receptor. Expression of KiSS-1 was higher in patients who had died from breast cancer than those who had remained healthy (4,631+/-3,024 vs 2,280+/-1,403) whereas expression of the receptor was reduced (480+/-162 vs 195+/-134). Immunohistochemical staining showed increased expression of KiSS-1 in tumour sections. Insertion of the KiSS-1 gene into the human breast cancer cell line MDA-MB-231, resulted in cells that were significantly more motile and invasive in behaviour, with reduced adhesion to matrix, using respective assays. In conclusion, KiSS-1 expression is increased in human breast cancer, particularly in patients with aggressive tumours and with mortality. Over-expression of KiSS-1 in breast cancer cells result in more aggressive phenotype. Together, it suggests that KiSS-1 plays a role beyond the initial metastasis repressor in this cancer type.

  PMID: 16320113 [PubMed - indexed for MEDLINE]

  
  
  
• Metastin and its G protein-coupled receptor, GPR54: critical pathway modulating GnRH secretion.
  

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  Metastin and its G protein-coupled receptor, GPR54: critical pathway modulating GnRH secretion.

  Front Neuroendocrinol. 2005 Oct-Dec;26(3-4):131-8

  Authors: Seminara SB

  Photoperiod, food availability, temperature, stress, and hormonal cues are some of the varied signals used by mammalian species to activate or suppress their timing of sexual maturation. All ultimately converge upon gonadotropin-releasing hormone (GnRH) secretion from the hypothalamus. Through its stimulation of LH and FSH from the pituitary, GnRH represents a critical step in the reproductive cascade. While few dispute this central role of GnRH, little is understood of the mechanisms influencing the developmental fate and physiologic controls of GnRH neurons. Identification of the signals which modulate pulsatile GnRH secretion is critical to advancing understanding of normal puberty and reproductive competency. The recent identification of loss-of-function mutations in GPR54, a receptor for kisspeptin-1, has highlighted a new pathway for the timing of puberty and reproductive control.

  PMID: 16309735 [PubMed - indexed for MEDLINE]

  
  
  
• Colocalization of kisspeptin and gonadotropin-releasing hormone in the ovine brain.
  

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  Colocalization of kisspeptin and gonadotropin-releasing hormone in the ovine brain.

  Endocrinology. 2006 Feb;147(2):804-10

  Authors: Pompolo S, Pereira A, Estrada KM, Clarke IJ

  Kisspeptin is a peptide that has been implicated in the regulation of GnRH cells in the brain. Immunohistochemical studies were undertaken to examine the distribution of kisspeptin-immunoreactive (IR) cells in the ovine diencephalon and determine the effect of ovariectomy in the ewe. We report that kisspeptin colocalizes to a high proportion of GnRH-IR cells in the preoptic area, which is a novel finding. A high level of colocalization of kisspeptin and GnRH was also seen in varicose neuronal fibers within the external, neurosecretory zone of the median eminence. Apart from the kisspeptin/GnRH cells, a population of single-labeling kisspeptin-IR cells was also observed in the preoptic area. Within the hypothalamus, kisspeptin-IR cells were found predominantly in the arcuate nucleus, and there was an increase in the number of immunohistochemically identified cell within this nucleus after ovariectomy. Kisspeptin-IR cells were also found in the periventricular nucleus of the hypothalamus, but the number observed was similar in gonad-intact and ovariectomized ewes. The colocalization of GnRH and kisspeptin within cells of the preoptic area and GnRH neurosecretory terminals of the median eminence suggests that the two peptides might be cosecreted into the hypophyseal portal blood to act on the pituitary gland. Effects of ovariectomy on the non-GnRH, Kisspeptin-IR cells of the hypothalamus suggest that kisspeptin production is negatively regulated by ovarian steroids.

  PMID: 16293663 [PubMed - indexed for MEDLINE]

  
  
  
• Kisspeptin-10-induced signaling of GPR54 negatively regulates chemotactic responses mediated by CXCR4: a potential mechanism for the metastasis suppressor activity of kisspeptins.
  

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  Kisspeptin-10-induced signaling of GPR54 negatively regulates chemotactic responses mediated by CXCR4: a potential mechanism for the metastasis suppressor activity of kisspeptins.

  Cancer Res. 2005 Nov 15;65(22):10450-6

  Authors: Navenot JM, Wang Z, Chopin M, Fujii N, Peiper SC

  The product of the KiSS-1 gene is absent or expressed at low level in metastatic melanoma and breast cancer compared with their nonmetastatic counterparts. A polypeptide derived from the KiSS-1 product, designated kisspeptin-10 (Kp-10), activates a receptor coupled to Galphaq subunits (GPR54 or KiSS-1R). To study the mechanism by which Kp-10 antagonizes metastatic spread, the effect on CXCR4-mediated signaling, which has been shown to direct organ-specific migration of tumor cells, was determined. Kp-10 blocked chemotaxis of tumor cells expressing CXCR4 in response to low and high concentrations of SDF-1/CXCL12 and inhibited mobilization of calcium ions induced by this ligand. Pretreatment with Kp-10 did not induce down-modulation of cell surface CXCR4 expression, reduce affinity for SDF-1/CXCL12, or alter Galphai subunit activation stimulated by this ligand. Although Kp-10 stimulated prolonged phosphorylation of extracellular signal-regulated kinase 1/2, it inhibited the phosphorylation of Akt induced by SDF-1. The ability of Kp-10 to inhibit signaling and chemotaxis induced by SDF-1 indicates that activation of GPR54 signaling may negatively regulate the role of CXCR4 in programming tumor metastasis.

  PMID: 16288036 [PubMed - indexed for MEDLINE]

  
  
  
• Repetitive activation of hypothalamic G protein-coupled receptor 54 with intravenous pulses of kisspeptin in the juvenile monkey (Macaca mulatta) elicits a sustained train of gonadotropin-releasing hormone discharges.
  

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  Repetitive activation of hypothalamic G protein-coupled receptor 54 with intravenous pulses of kisspeptin in the juvenile monkey (Macaca mulatta) elicits a sustained train of gonadotropin-releasing hormone discharges.

  Endocrinology. 2006 Feb;147(2):1007-13

  Authors: Plant TM, Ramaswamy S, Dipietro MJ

  The purpose of the present study was to further examine the hypothesis that activation of G protein-coupled receptor 54 (GPR54) signaling at the end of the juvenile phase of primate development is responsible for initiation of gonadarche and the onset of puberty. Accordingly, we determined whether repetitive iv administration of the GPR54 receptor agonist kisspeptin-10 (2 microg as a brief 1-min infusion once every hour for 48 h) to the juvenile male rhesus monkey would prematurely elicit sustained, pulsatile release of hypothalamic GnRH, the neuroendocrine trigger for gonadarche. GnRH release was monitored indirectly by measuring LH secretion from the in situ pituitary, the GnRH responsiveness of which had been heightened before the experiment with an intermittent iv infusion of synthetic GnRH. Agonadal animals (n = 4) were employed to eliminate any confounding and secondary effects of changing feedback signals from the testis. The first brief infusion of kisspeptin-10 evoked an LH discharge that mimicked those produced by GnRH priming, and this was followed by a train of similar LH discharges in response to hourly activation of GPR54 by repetitive kisspeptin-10 administration. Concomitant treatment with a GnRH receptor antagonist, acyline, abolished kisspeptin-10-induced LH release. Repetitive kisspeptin-10 administration also provided a GnRH-dependent signal to FSH secretion. These findings are consistent with the notion that, in primates, the transition from the juvenile (attenuated GnRH release) to pubertal (robust GnRH release) state is controlled by activation of GPR54 resulting from increased expression of hypothalamic KiSS-1 and release of kisspeptin in this region of the brain.

  PMID: 16282350 [PubMed - indexed for MEDLINE]

  
  
  
• [Expression and significance of KiSS-1 and its receptor GPR54 mRNA in epithelial ovarian cancer]
  

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  [Expression and significance of KiSS-1 and its receptor GPR54 mRNA in epithelial ovarian cancer]

  Zhonghua Fu Chan Ke Za Zhi. 2005 Oct;40(10):689-92

  Authors: Zhang SL, Yu Y, Jiang T, Lin B, Gao H

  OBJECTIVE: To study the expression and significance of metastasis suppressor gene KiSS-1 and its receptor GPR54 in epithelial ovarian cancer. METHOD: The expression and their clinical significance of KiSS-1 and GPR54 were evaluated by RT-PCR in 37 patients with epithelial ovarian cancer, 15 patients with borderline epithelial ovarian tumors, 15 patients with epithelial benign tumors and 11 patients with normal ovarian tissues. RESULTS: The positivity and relative contents of KiSS-1 mRNA in patients with epithelial ovarian cancer (68%, 0.82 +/- 0.09) and borderline epithelial ovarian tumors (60%, 0.80 +/- 0.10) were all higher than in patients with epithelial benign tumor (20%, 0.65 +/- 0.10) and normal ovarian tissues (18%, 0.66 +/- 0.06; P < 0.05). The positivity and relative contents of KiSS-1 mRNA in patients with epithelial ovarian cancer correlated with their clinical stage and lymph node metastasis (P < 0.05). There was no difference in the positivity and relative contents of GPR54 mRNA between patients with epithelial ovarian cancer (70%, 0.79 +/- 0.07), borderline epithelial ovarian tumor (67%, 0.76 +/- 0.10), benign epithelial ovarian tumor (60%, 0.73 +/- 0.07) and normal ovarian tissues (45%, 0.78 +/- 0.08), respectively (all P > 0.05). The positivity and relative contents of GPR54 mRNA in patients with epithelial ovarian cancer did not correlate with their clinical stage, histology grade, lymph node metastasis and production of ascites (P > 0.05). CONCLUSION: KiSS-1 and GPR54 may play an important role in inhibiting the invasion and metastasis of early epithelial ovarian cancer.

  PMID: 16277902 [PubMed - indexed for MEDLINE]

  
  
  
• Regulation of KiSS-1 metastasis suppressor gene expression in breast cancer cells by direct interaction of transcription factors activator protein-2alpha and specificity protein-1.
  

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  Regulation of KiSS-1 metastasis suppressor gene expression in breast cancer cells by direct interaction of transcription factors activator protein-2alpha and specificity protein-1.

  J Biol Chem. 2006 Jan 6;281(1):51-8

  Authors: Mitchell DC, Abdelrahim M, Weng J, Stafford LJ, Safe S, Bar-Eli M, Liu M

  KiSS-1 has been shown to function as a tumor metastasis suppressor gene and reduce the number of metastases in different cancers. The expression of KiSS-1 or KiSS1, like other tumor suppressor, is commonly reduced or completely ablated in a variety of cancers via an unknown mechanism. Here we show that the loss of KiSS-1 expression in highly metastatic breast cancer cell lines correlates directly with the expression levels of two transcription factors, activator protein-2alpha (AP-2alpha) and specificity protein 1 (Sp1), which synergistically activate the transcriptional regulation of KiSS-1 in breast cancer cells. Although the KiSS-1 promoter contains multiple AP-2alpha binding elements, AP-2alpha-mediated regulation occurs indirectly through Sp1 sites, as determined by deletion and mutation analysis. Overexpression of AP-2alpha into highly metastatic breast cell lines did not alter KiSS-1 promoter-driven luciferase gene activity. However, co-transfection of AP-2alpha wild-type or the dominant negative form of AP-2 lacking its C-terminal DNA-binding domain, AP-2B, together with Sp1, increased KiSS-1 promoter activity dramatically, suggesting that AP-2alpha regulation of KiSS-1 transcription does not require direct binding to the KiSS-1 promoter. Furthermore, we demonstrated that AP-2alpha directly interacted with Sp1 to form transcription complexes at two tandem Sp1-binding sites of the promoter to activate KiSS-1 transcription. Together, our results indicate that AP-2alpha and Sp1 are strong transcriptional regulators of KiSS-1 and that loss or decreased expression of AP-2alpha in breast cancer may account for the loss of tumor metastasis suppressor KiSS-1 expression and thus increased cancer metastasis.

  PMID: 16260418 [PubMed - indexed for MEDLINE]

  
  
  
• Design and synthesis of downsized metastin (45-54) analogs with maintenance of high GPR54 agonistic activity.
  

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  Design and synthesis of downsized metastin (45-54) analogs with maintenance of high GPR54 agonistic activity.

  Bioorg Med Chem Lett. 2006 Jan 1;16(1):134-7

  Authors: Niida A, Wang Z, Tomita K, Oishi S, Tamamura H, Otaka A, Navenot JM, Broach JR, Peiper SC, Fujii N

  Metastin has been identified as a metastasis suppressor gene product that mediates its function through a G protein coupled receptor, GPR54. To refine insight into the critical pharmacophore for the activation of GPR54, we have conducted alanine and d-amino acid scanning on a biologically active metastin fragment (45-54). Based on these data and structures of peptides previously reported to activate GPR54, a series of shortened metastin (45-54) derivatives were synthesized and tested for the ability to induce GPR54 signaling. These biological experiments were performed in yeast containing human GPR54 that was coupled to the pheromone response pathway and a pheromone responsive lacZ reporter gene. Compounds 32, 33, and 39, which possess an N-terminal basic group and a C-terminal RW-amide motif, were strong agonists, similar to the level of metastin. This may provide an approach to reverse the pro-metastatic effect of metastin deletion in multiple malignant tumors.

  PMID: 16242330 [PubMed - indexed for MEDLINE]

  
  
  
• Cancer metastasis-suppressing peptide metastin upregulates excitatory synaptic transmission in hippocampal dentate granule cells.
  

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  Cancer metastasis-suppressing peptide metastin upregulates excitatory synaptic transmission in hippocampal dentate granule cells.

  J Neurophysiol. 2005 Nov;94(5):3648-52

  Authors: Arai AC, Xia YF, Suzuki E, Kessler M, Civelli O, Nothacker HP

  Metastin is an antimetastatic peptide encoded by the KiSS-1 gene in cancer cells. Recent studies found that metastin is a ligand for the orphan G-protein-coupled receptor GPR54, which is highly expressed in specific brain regions such as the hypothalamus and parts of the hippocampus. This study shows that activation of GPR54 by submicromolar concentrations of metastin reversibly enhances excitatory synaptic transmission in hippocampal dentate granule cells in a mitogen-activated protein (MAP) kinase-dependent manner. Synaptic enhancement by metastin was suppressed by intracellular application of the G-protein inhibitor GDP-beta-S and the calcium chelator BAPTA. Analysis of miniature excitatory postsynaptic currents (mEPSCs) revealed an increase in the mean amplitude but no change in event frequency. This indicates that GPR54 and the mechanism responsible for the increase in EPSCs are postsynaptic. Metastin-induced synaptic potentiation was abolished by 50 microM PD98059 and 20 microM U0126, two inhibitors of the MAP kinases ERK1 and ERK2. The effect was also blocked by inhibitors of calcium/calmodulin-dependent kinases and tyrosine kinases. RT-PCR experiments showed that both KiSS-1 and GPR54 are expressed in the hippocampal dentate gyrus. Metastin is thus a novel endogenous factor that modulates synaptic excitability in the dentate gyrus through mechanisms involving MAP kinases, which in turn may be controlled upstream by calcium-activated kinases and tyrosine kinases.

  PMID: 16222076 [PubMed - indexed for MEDLINE]

  
  
  
• [Clinical significance of KiSS-1 and matrix metalloproteinase-9 expression in trophoblasts of women with preeclampsia and their relation to perinatal outcome of neonates]
  

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  [Clinical significance of KiSS-1 and matrix metalloproteinase-9 expression in trophoblasts of women with preeclampsia and their relation to perinatal outcome of neonates]

  Zhonghua Fu Chan Ke Za Zhi. 2005 Sep;40(9):585-90

  Authors: Qiao C, Wang CH, Shang T, Lin QD

  OBJECTIVE: To investigate the role of KiSS-1 and matrix metalloproteinase (MMP) 9 in trophoblasts in the pathogenesis of preeclampsia and their relation to perinatal outcome of neonates. METHODS: RT-PCR and western blot analyses were used to detect the MMP-9 and KiSS-1 expression levels in trophoblast of 40 patients with preeclampsia (15 cases of mild and 25 cases of severe preeclampsia) (preeclampsia group) and 20 cases of term pregnancy (normal pregnancy group) and their correlations with symptoms and perinatal outcome of neonates were analyzed. RESULTS: (1) The KiSS-1mRNA and metastin expression levels in trophoblasts of preeclampsia group were 1.73 +/- 0.24 (A value) and (78.4 +/- 8.0) microg/100 microg total protein separately, those of mild preeclampsia were (1.50 +/- 0.15) and (72.4 +/- 6.9) microg/100 microg total protein, and severe preeclampsia were (1.87 +/- 0.20) and (83.52 +/- 3.57) microg/100 microg total protein, which were all significantly higher than those of normal pregnancy group [1.24 +/- 0.25, P < 0.01, and (63.4 +/- 2.7) microg/100 microg total protein, P < 0.01], especially those in severe preeclampsia. (2) The MMP-9 mRNA and MMP-9 expression levels in trophoblasts of preeclampsia group were 0.09 +/- 0.06 and (9.6 +/- 4.2) microg/100 microg total protein, those of mild preeclampsia were 0.11 +/- 0.08 and (10.0 +/- 3.2) microg/100 microg total protein, and severe preeclampsia were 0.07 +/- 0.05 and (7.8 +/- 2.0) microg/100 microg total protein, which were all significantly lower than those of normal pregnancy group [0.17 +/- 0.10, P < 0.01, and (17.9 +/- 7.3) microg/100 microg total protein, P < 0.01]. (3) The expression level of KiSS-1mRNA and metastin in preeclampsia group were positively correlated with MAP, urinary protein per 24 hours, the correlation coefficients between KiSS-1mRNA and MAP, urinary protein per 24 hours were 0.610 (P = 0.023), 0.397 (P = 0.003), and between metastin and MAP, urinary protein per 24 hours were 0.713 (P = 0.011), 0.638 (P = 0.002), separately. The expression level of KiSS-1mRNA and metastin in preeclampsia group was significantly positively correlated with the occurrence of fundus oculi artery spasm, correlation coefficients were 0.499 (P = 0.000) and 0.511 (P = 0.000). The MMP-9mRNA and MMP-9 expression levels were negatively correlated with MAP, urinary protein per 24 hours and the occurrence of fundus oculi artery spasm, correlation coefficients between MMP-9mRNA and MAP, urinary protein per 24 hours, the occurrence of fundus oculi artery spasm were 0.561 (P = 0.042), 0.275 (P = 0.039), 0.346 (P = 0.001), between MMP-9 and MAP, urinary protein per 24 hours, the occurrence of fundus oculi artery...
  
  

• Kisspeptin-54 stimulates the hypothalamic-pituitary gonadal axis in human males.
  

  Kisspeptin-54 stimulates the hypothalamic-pituitary gonadal axis in human males.

  J Clin Endocrinol Metab. 2005 Dec;90(12):6609-15

  Authors: Dhillo WS, Chaudhri OB, Patterson M, Thompson EL, Murphy KG, Badman MK, McGowan BM, Amber V, Patel S, Ghatei MA, Bloom SR

  CONTEXT: Mutation of the G protein-coupled receptor 54 is associated with a failure of reproductive function. The endogenous neuropeptide agonist for G protein-coupled receptor 54, kisspeptin, potently stimulates the hypothalamic-pituitary-gonadal axis in rodents and primates. OBJECTIVE: The present study was designed to determine the effects of elevating circulating kisspeptin levels on LH, FSH, and testosterone in male volunteers. DESIGN: This was a double-blind, placebo-controlled, crossover study. Setting: This was a hospital-based study. PARTICIPANTS: Male volunteers (n = 6) were recruited. INTERVENTIONS: Each volunteer received a 90-min i.v. infusion of kisspeptin-54 (4 pmol/kg x min) and a control infusion of saline (0.9%) in random order. MAIN OUTCOME MEASURE: Plasma LH, FSH, and testosterone concentrations were measured. RESULTS: Kisspeptin-54 infusion significantly increased plasma LH, FSH, and testosterone concentrations compared with saline infusion (mean 90-min LH: kisspeptin, 10.8 +/- 1.5 vs. saline, 4.2 +/- 0.5 U/liter, P < 0.001; mean 90-min FSH: kisspeptin, 3.9 +/- 0.7 vs. saline, 3.2 +/- 0.6 U/liter, P < 0.001; mean 180-min testosterone: kisspeptin, 24.9 +/- 1.7 vs. saline, 21.7 +/- 2.2 nmol/liter, P < 0.001). The plasma half-life of kisspeptin-54 was calculated to be 27.6 +/- 1.1 min. The mean metabolic clearance rate was 3.2 +/- 0.2 ml/kg x min, and the volume of distribution was 128.9 +/- 12.5 ml/kg. CONCLUSION: Elevation of plasma concentrations of kisspeptin in human males significantly increases circulating LH, FSH, and testosterone levels. Kisspeptin infusion provides a novel mechanism for hypothalamic-pituitary-gonadal axis manipulation in disorders of the reproductive system.

  PMID: 16174713 [PubMed - indexed for MEDLINE]

  
  
  
• Kisspeptin and its receptor: new gatekeepers of puberty.
  

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  Kisspeptin and its receptor: new gatekeepers of puberty.

  J Neuroendocrinol. 2005 Oct;17(10):687-8

  Authors: Messager S

  The recent finding that the hormone kisspeptin plays a pivotal role in the onset of puberty is one of the biggest discoveries in human reproductive biology in 30 years. Mutations in the receptor for kisspeptin cause humans and mice to fail to reach puberty and to be sterile. It is the first time since the identification of gonadotrophin-releasing hormone that a single gene is found to have such a dramatic effect on reproduction. This discovery opens new possibilities in the treatment of reproductive disorders such as delayed or advanced puberty, infertility and sex hormone-dependent cancers.

  PMID: 16159382 [PubMed - indexed for MEDLINE]

  
  
  
• Hypothalamic KiSS-1: the missing link in gonadotropin feedback control?
  

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  Hypothalamic KiSS-1: the missing link in gonadotropin feedback control?

  Endocrinology. 2005 Sep;146(9):3683-5

  Authors: Tena-Sempere M

  PMID: 16105827 [PubMed - indexed for MEDLINE]

  
  
  
• Kisspeptins and GPR54--the new biology of the mammalian GnRH axis.
  

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  Kisspeptins and GPR54--the new biology of the mammalian GnRH axis.

  Cell Metab. 2005 May;1(5):293-6

  Authors: Aparicio SA

  Recent genetic evidence in humans and from mouse knockouts has linked kisspeptin-driven GPR54 signaling to the regulation of GnRH release from the hypothalamus. These molecules appear to represent a previously unsuspected control point for GnRH secretion, with important implications for the biology and pathology of the sex steroid axis.

  PMID: 16054076 [PubMed - indexed for MEDLINE]

  
  
  
• Reproductive biology. A powerful first KiSS-1.
  

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  Reproductive biology. A powerful first KiSS-1.

  Science. 2005 Jul 22;309(5734):551-2

  Authors: Vogel G

  PMID: 16040685 [PubMed - indexed for MEDLINE]

  
  
  
• KiSS-1 and GPR54 as new players in gonadotropin regulation and puberty.
  

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  KiSS-1 and GPR54 as new players in gonadotropin regulation and puberty.

  Endocrine. 2005 Apr;26(3):277-84

  Authors: Kaiser UB, Kuohung W

  The recent identification of loss-of-function mutations in the gene encoding GPR54, the receptor for the KiSS-1-derived peptides, kisspeptins, has highlighted a previously unrecognized pathway in the physiologic regulation of puberty and reproduction. Patients with loss-of-function mutations in GPR54 have idiopathic hypogonadotropic hypogonadism, and mice lacking GPR54 similarly fail to undergo puberty and have immature reproductive organs and low levels of sex steroids and gonadotropins. These observations have led to the hypothesis that kisspeptins activate hypothalamic GnRH release, thereby serving as a pivotal factor in the pubertal activation of the reproductive cascade. This hypothesis is supported by subsequent studies in rodent and primate models that have demonstrated localization of KiSS-1 mRNA in the hypothalamus, colocalization of GPR54 in GnRH neurons, GnRH-dependent activation of LH and FSH release by intracerebroventricular or peripheral administration of kisspeptin, and increased hypothalamic KiSS-1 and GPR54 mRNA levels at the onset of puberty. Taken together, these findings weave a compelling case for a role of the kisspeptin-GPR54 system in the activation of GnRH neurons at the time of pubertal awakening of the reproductive axis.

  PMID: 16034182 [PubMed - indexed for MEDLINE]

  
  
  
• Kisspeptins: regulators of metastasis and the hypothalamic-pituitary-gonadal axis.
  

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  Kisspeptins: regulators of metastasis and the hypothalamic-pituitary-gonadal axis.

  J Neuroendocrinol. 2005 Aug;17(8):519-25

  Authors: Murphy KG

  The kisspeptins are the peptide products of the KiSS-1 gene and the endogenous agonists for the GPR54 receptor. Although KiSS-1 was initially discovered as a metastasis suppressor gene, recent evidence suggests the kisspeptin/GPR54 system is a key regulator of the reproductive system. Disrupted GPR54 signalling causes hypogonadotrophic hypogonadism in rodents and man. Central or peripheral administration of kisspeptin potently stimulates the hypothalamic-pituitary-gonadal axis, increasing circulating gonadotrophin concentrations in a number of animal models. These effects appear likely to be mediated via the hypothalamic gonadotrophin-releasing hormone system, although kisspeptins may have direct effects on the anterior pituitary gland. Hypothalamic KiSS-1 expression is regulated by circulating sex steroids. The precise physiological role of the kisspeptin system in the regulation of reproductive function remains to be elucidated.

  PMID: 16011488 [PubMed - indexed for MEDLINE]

  
  
  
• KiSS-1/G protein-coupled receptor 54 metastasis suppressor pathway increases myocyte-enriched calcineurin interacting protein 1 expression and chronically inhibits calcineurin activity.
  

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  KiSS-1/G protein-coupled receptor 54 metastasis suppressor pathway increases myocyte-enriched calcineurin interacting protein 1 expression and chronically inhibits calcineurin activity.

  J Clin Endocrinol Metab. 2005 Sep;90(9):5432-40

  Authors: Stathatos N, Bourdeau I, Espinosa AV, Saji M, Vasko VV, Burman KD, Stratakis CA, Ringel MD

  OBJECTIVE: Tumor metastasis is a critical determinant of death from cancer. Metastin, a product of the KiSS-1 gene, is an endogenously expressed metastasis suppressor that is the ligand for G protein-coupled receptor 54 (GPR54), a Gq/11-coupled receptor. In the present study, our goal was to define the basis of GPR54 action using thyroid cancer cells as a model. DESIGN AND RESULTS: We used GPR54-null thyroid cancer cells to create a stable GPR54 overexpression model. Cell growth and cell migration of the GPR54-expressing lines were inhibited by recombinant metastin, and metastin stimulated the protein kinase C, ERK, and phosphatidylinositol-3-kinase pathways. To identify metastin-regulated genes, we performed microarray analyses using RNA isolated from GPR54 stable transfectants before and after 1 and 24 h of metastin stimulation. Consistent increases in expression of the gene encoding myocyte-enriched calcineurin interacting protein 1 (MCIP-1), an inhibitor of calcineurin, were identified and confirmed using real-time RT-PCR and Western blot. Functionally, metastin treatment of GPR54-expressing cells initially increased calcineurin activity, followed by a prolonged reduction in calcineurin activity for 24 and 48 h, consistent with the pattern of MCIP-1 expression. In addition, treatment with cyclosporin A, a calcineurin inhibitor, blocked cell migration. Lymph node metastasis in papillary thyroid cancers demonstrated loss of MCIP-1 expression in comparison with primary tumors. CONCLUSIONS: These data suggest a role for MCIP-1 and calcineurin inhibition in GPR54-mediated metastasis suppression in human cancers.

  PMID: 15998767 [PubMed - indexed for MEDLINE]

  
  
  
• Involvement of central metastin in the regulation of preovulatory luteinizing hormone surge and estrous cyclicity in female rats.
  

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  Involvement of central metastin in the regulation of preovulatory luteinizing hormone surge and estrous cyclicity in female rats.

  Endocrinology. 2005 Oct;146(10):4431-6

  Authors: Kinoshita M, Tsukamura H, Adachi S, Matsui H, Uenoyama Y, Iwata K, Yamada S, Inoue K, Ohtaki T, Matsumoto H, Maeda K

  Ovulation is caused by a sequence of neuroendocrine events: GnRH and LH surges that are induced by positive feedback action of estrogen secreted by the mature ovarian follicles. The central mechanism of positive feedback action of estrogen on GnRH/LH secretion, however, is not fully understood yet. The present study examined whether metastin, the product of metastasis suppressor gene KiSS-1, is a central neuropeptide regulating GnRH/LH surge and then estrous cyclicity in the female rat. Metastin had a profound stimulation on LH secretion by acting on the preoptic area (POA), where most GnRH neurons projecting to the median eminence are located, because injection of metastin into the third ventricle or POA increased plasma LH concentrations in estrogen-primed ovariectomized rats. Metastin neurons were immunohistochemically found in the arcuate nucleus (ARC) to be colocalized with estrogen receptors with some fibers in the preoptic area (POA) in close apposition with GnRH neuronal cell bodies or fibers. Quantitative RT-PCR has revealed that KiSS-1 and GPR54 mRNAs were expressed in the ARC and POA, respectively. The blockade of local metastin action in the POA with a specific monoclonal antibody to rat metastin completely abolished proestrous LH surge and inhibited estrous cyclicity. Metastin-immunoreactive cell bodies in the ARC showed a marked increase and c-Fos expression in the early proestrus afternoon compared with the day of diestrus. Thus, metastin released in the POA is involved in inducing the preovulatory LH surge and regulating estrous cyclicity.

  PMID: 15976058 [PubMed - indexed for MEDLINE]

  
  
  
• Discovery of novel regulatory peptides by reverse pharmacology: spotlight on chemerin and the RF-amide peptides metastin and QRFP.
  

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  Discovery of novel regulatory peptides by reverse pharmacology: spotlight on chemerin and the RF-amide peptides metastin and QRFP.

  Curr Protein Pept Sci. 2005 Jun;6(3):265-78

  Authors: Kutzleb C, Busmann A, Wendland M, Maronde E

  Reverse pharmacology is a screening technology that matches G protein-coupled receptors (GPCRs) with unknown cognate ligands in cell-based screening assays by detection of agonist-induced signaling pathways. One decade spent pursuing orphan GPCR screening by this technique assigned over 30 ligand/receptor pairs and revealed previously known or novel undescribed ligands, mostly of a peptidic nature. In this review, we describe the discovery, characterization of the structural composition, biological function, physiological role and therapeutic potential of three recently identified peptidic ligands. These are metastin, QRFP in a context of five RF-amide genes described in humans and the chemoattractant, chemerin. Metastin was initially characterized as a metastasis inhibitor. Investigations using ligand/receptor pairing revealed that metastin was involved in a variety of physiological processes, including endocrine function during pregnancy and gonad development. The novel RF-amide QRFP is implicated in food intake and aldosterone release from the adrenal cortex in the rat. Chemerin, first described as TIG2, is upregulated in tazarotene-treated psoriatic skin. By GPCR screening, bioactive chemerin was isolated from ovarial carcinoma fluid as well as hemofiltrate. Characterization as a chemoattractant for immature dendritic cells and analysis of the expression profile of metastin and its receptor suggested a physiological role of chemerin as a mediator of the immune response, inflammatory processes and bone development.

  PMID: 15974952 [PubMed - indexed for MEDLINE]

  
  
  
• [Expression and clinical significance of KISS-1 and GPR54 mRNA in endometrial carcinoma]
  

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  [Expression and clinical significance of KISS-1 and GPR54 mRNA in endometrial carcinoma]

  Zhonghua Zhong Liu Za Zhi. 2005 Apr;27(4):229-31

  Authors: Jiang T, Zhang SL, Lin B, Meng LR, Gao H

  OBJECTIVE: To investigate the expression and clinical significance of KISS-1 mRNA and GPR54 mRNA in endometrial carcinoma. METHODS: The expression of KISS-1 mRNA and GPR54 mRNA in 32 patients with endometrial carcinoma, 10 patients with endometrial intraepithelial neoplasia (EIN) and 12 patients with normal endometrium was detected by reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: The positive rate of KISS-1 mRNA in endometrial carcinoma, EIN and normal endometrium was 37.5%, 80.0% and 83.3% respectively (endometrial carcinoma vs EIN or normal endometrium, P < 0.05). The expression of KISS-1mRNA in patients with endometrial carcinoma was correlated with its clinical stage, myometrial invasion and lymph node metastasis (P < 0.05). In endometrial carcinoma, the more advanced clinical stage, the lower expression of KISS-1 mRNA was detected. The positive rate of GPR54 mRNA in endometrial carcinoma, EIN and normal endometrium was 78.1%, 70.0% and 66.7% respectively, with no significant statistical difference (P > 0.05). It was not correlated with the clinical stage, histology grade, myometrial invasion or lymph node metastasis (P > 0.05). CONCLUSION: The interaction of KISS-1 and GPR54 may play an important role in inhibiting the invasion and metastasis of endometrial carcinoma.

  PMID: 15949424 [PubMed - indexed for MEDLINE]

  
  
  
• [The role of KiSS-1 and matrix metalloproteinase-9 in regulation of invasion of trophoblasts]
  

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  [The role of KiSS-1 and matrix metalloproteinase-9 in regulation of invasion of trophoblasts]

  Zhonghua Yi Xue Za Zhi. 2005 Mar 30;85(12):839-42

  Authors: Qiao C, Cheng DL, Zhang SL, Wang CH, Lin QD

  OBJECTIVE: To explore the role of metastasis-related gene KiSS-1 and matrix metalloproteinase (MMP)-9 in regulation of invasion of trophoblasts. METHODS: RT-PCR and Western blotting were used to detect the MMP-9 and KiSS-1 expression levels in the placental tissues obtained from 90 cases of normal pregnant women undergoing artificial abortion, induction of labor with water bag or selective cesarean section among which 30 cases were in the first trimester, 30 in second-trimester and 30 cases of term pregnancy, and in the placental tissues of 40 cases of preeclampsia (15 cases of mild and 25 cases of severe preeclampsia) undergoing cesarean section, and tissues of 90 cases of hydatidiform mole, 9 cases of invasive mole and 8 cases of choriocarcinoma, all undergoing surgery. RESULTS: The expression levels of MMP-9 mRNA and protein were higher in first-trimester [A value 0.391 +/- 0.215, (36 +/- 7) microg/100 microg total protein] and then decreased gradually with the progress of gestation. The expression levels of MMP-9mRNA and protein in the term placental samples were significantly lower than those of first-trimester (both P < 0.01). The expression levels of KiSS-1mRNA and metastin in normal placenta increased along with the progress of gestation (both P < 0.01). The KISS-1 mRNA expression level and MMP-9 protein expression level in the placental tissue of preeclampsia were 0.09 +/- 0.06 (A value) and (9.6 +/- 4.3) microg/100 microg total protein respectively, both significantly lower than those of the term placenta (both P < 0.01). The expression levels of MMP-9 mRNA and protein in the tissues of gestational trophoblastic disease were significantly higher than those in the first-trimester placenta (both P < 0.01). The expression level of KISS-1 mRNA and metastin in the tissues of hyddatidiform mole and invasive mole were both significantly lower than those in the first trimester placenta (P < 0.05, P < 0.01). The expression of KiSS-1mRNA and metastin in the tissues of choriocarcinoma could not be detected. CONCLUSION: The expression of the invasion-related gene, MMP-9, is positively related with, while the invasion suppressor gene, KiSS-1, is negatively related with the invasive ability of trophoblasts. The interaction of these two genes plays an important role in regulation of the invasion of trophoblasts.

  PMID: 15949403 [PubMed - indexed for MEDLINE]

  
  
  
• Changes in hypothalamic KiSS-1 system and restoration of pubertal activation of the reproductive axis by kisspeptin in undernutrition.
  

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  Changes in hypothalamic KiSS-1 system and restoration of pubertal activation of the reproductive axis by kisspeptin in undernutrition.

  Endocrinology. 2005 Sep;146(9):3917-25

  Authors: Castellano JM, Navarro VM, Fernández-Fernández R, Nogueiras R, Tovar S, Roa J, Vazquez MJ, Vigo E, Casanueva FF, Aguilar E, Pinilla L, Dieguez C, Tena-Sempere M

  Activation of the gonadotropic axis critically depends on sufficient body energy stores, and conditions of negative energy balance result in lack of puberty onset and reproductive failure. Recently, KiSS-1 gene-derived kisspeptin, signaling through the G protein-coupled receptor 54 (GPR54), has been proven as a pivotal regulator in the control of gonadotropin secretion and puberty. However, the impact of body energy status upon hypothalamic expression and function of this system remains unexplored. In this work, we evaluated the expression of KiSS-1 and GPR54 genes at the hypothalamus as well as the ability of kisspeptin-10 to elicit GnRH and LH secretion in prepubertal rats under short-term fasting. In addition, we monitored the actions of kisspeptin on food intake and the effects of its chronic administration upon puberty onset in undernutrition. Food deprivation induced a concomitant decrease in hypothalamic KiSS-1 and increase in GPR54 mRNA levels in prepubertal rats. In addition, LH responses to kisspeptin in vivo were enhanced, and its GnRH secretagogue action in vitro was sensitized, under fasting conditions. Central kisspeptin administration failed to change food intake patterns in animals fed ad libitum or after a 12-h fast. However, chronic treatment with kisspeptin was able to restore vaginal opening (in approximately 60%) and to elicit gonadotropin and estrogen responses in a model of undernutrition. In summary, our data are the first to show an interaction between energy status and the hypothalamic KiSS-1 system, which may constitute a target for disruption (and eventual therapeutic intervention) of pubertal development in conditions of negative energy balance.

  PMID: 15932928 [PubMed - indexed for MEDLINE]

  
  
  
• Regulation of Kiss1 gene expression in the brain of the female mouse.
  

  Regulation of Kiss1 gene expression in the brain of the female mouse.

  Endocrinology. 2005 Sep;146(9):3686-92

  Authors: Smith JT, Cunningham MJ, Rissman EF, Clifton DK, Steiner RA

  The Kiss1 gene encodes a family of neuropeptides called kisspeptins, which activate the receptor G protein-coupled receptor-54 and play a role in the neuroendocrine regulation of GnRH secretion. We examined whether estradiol (E2) regulates KiSS-1 in the forebrain of the female mouse by comparing KiSS-1 mRNA expression among groups of ovary-intact (diestrus), ovariectomized (OVX), and OVX plus E2-treated mice. In the arcuate nucleus (Arc), KiSS-1 expression increased after ovariectomy and decreased with E2 treatment. Conversely, in the anteroventral periventricular nucleus (AVPV), KiSS-1 expression was reduced after ovariectomy and increased with E2 treatment. To determine whether the effects of E2 on KiSS-1 are mediated through estrogen receptor (ER)alpha or ERbeta, we evaluated the effects of E2 in OVX mice that lacked functional ERalpha or ERbeta. In OVX mice that lacked functional ERalpha, KiSS-1 mRNA did not respond to E2 in either the Arc or AVPV, suggesting that ERalpha is essential for mediating the inhibitory and stimulatory effects of E2. In contrast, KiSS-1 mRNA in OVX mice that lacked functional ERbeta responded to E2 exactly as wild-type animals. Double-label in situ hybridization revealed that virtually all KiSS-1-expressing neurons in the Arc and AVPV coexpress ERalpha, suggesting that the effects of E2 are mediated directly through KiSS-1 neurons. We conclude that KiSS-1 neurons in the Arc, which are inhibited by E2, may play a role in the negative feedback regulation of GnRH secretion, whereas KiSS-1 neurons in the AVPV, which are stimulated by E2, may participate in the positive feedback regulation of GnRH secretion.

  PMID: 15919741 [PubMed - indexed for MEDLINE]

  
  
  
• Differential regulation of KiSS-1 mRNA expression by sex steroids in the brain of the male mouse.
  

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  Differential regulation of KiSS-1 mRNA expression by sex steroids in the brain of the male mouse.

  Endocrinology. 2005 Jul;146(7):2976-84

  Authors: Smith JT, Dungan HM, Stoll EA, Gottsch ML, Braun RE, Eacker SM, Clifton DK, Steiner RA

  Kisspeptins are products of the Kiss1 gene, which bind to GPR54, a G protein-coupled receptor. Kisspeptins and GPR54 have been implicated in the neuroendocrine regulation of GnRH secretion. To test the hypothesis that testosterone regulates Kiss1 gene expression, we compared the expression of KiSS-1 mRNA among groups of intact, castrated, and castrated/testosterone (T)-treated male mice. In the arcuate nucleus (Arc), castration resulted in a significant increase in KiSS-1 mRNA, which was completely reversed with T replacement, whereas in the anteroventral periventricular nucleus, the results were the opposite, i.e. castration decreased and T increased KiSS-1 mRNA expression. In the Arc, the effects of T on KiSS-1 mRNA were completely mimicked by estrogen but only partially mimicked by dihydrotestosterone, a nonaromatizable androgen, suggesting that both estrogen receptor (ER) and androgen receptor (AR) play a role in T-mediated regulation of KiSS-1. Studies of the effects of T on KiSS-1 expression in mice with either a deletion of the ERalpha or a hypomorphic allele to the AR revealed that the effects of T are mediated by both ERalpha and AR pathways, which was confirmed by the presence of either ERalpha or AR coexpression in most KiSS-1 neurons in the Arc. These observations suggest that KiSS-1 neurons in the Arc, whose transcriptional activity is inhibited by T, are targets for the negative feedback regulation of GnRH secretion, whereas KiSS-1 neurons in the anteroventral periventricular nucleus, whose activity is stimulated by T, may mediate other T-dependent processes.

  PMID: 15831567 [PubMed - indexed for MEDLINE]

  
  
  
• New gatekeepers of reproduction: GPR54 and its cognate ligand, KiSS-1.
  

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  New gatekeepers of reproduction: GPR54 and its cognate ligand, KiSS-1.

  Endocrinology. 2005 Apr;146(4):1686-8

  Authors: Seminara SB, Kaiser UB

  PMID: 15769900 [PubMed - indexed for MEDLINE]

  
  
  
• Molecular genetics of isolated hypogonadotropic hypogonadism and Kallmann syndrome.
  

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  Molecular genetics of isolated hypogonadotropic hypogonadism and Kallmann syndrome.

  Endocr Dev. 2005;8:67-80

  Authors: Karges B, de Roux N

  Isolated hypogonadotropic hypogonadism (IHH) is characterized by complete or partial failure of pubertal development due to impaired secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). In the molecular pathogenesis of IHH, the gonadotropin-releasing hormone receptor (GnRH-R) and associated proteins have evolved as a central element. GnRH-R germline mutations were among the first genetic alterations identified in patients with IHH. These mutations are associated with impaired GnRH binding, ligand-induced signal transduction, or both, leading to various degrees of LH and FSH deficiency. As GnRH-R mutations explain several but not all cases of IHH, the search for new candidate genes continued in informative families. In 2003, mutations of the KiSS-1-derived peptide receptor GPR54 were identified in patients with IHH, opening a new pathway in the physiologic regulation of puberty and reproduction. GPR54 is putatively involved in the control of GnRH secretion. IHH associated with impaired olfactory function (Kallmann syndrome) may be caused by mutations of the X-chromosomal KAL1 (encoding anosmin) or the fibroblast growth factor receptor 1 genes (FGFR1), both leading to agenesis of olfactory and GnRH-secreting neurons. In addition to their clinical and diagnostic value, the identification of genetic and functional alterations in IHH helps to unravel the complex regulation of the gonadotropic axis.

  PMID: 15722618 [PubMed - indexed for MEDLINE]

  
  
  
• Increased hypothalamic GPR54 signaling: a potential mechanism for initiation of puberty in primates.
  

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  Increased hypothalamic GPR54 signaling: a potential mechanism for initiation of puberty in primates.

  Proc Natl Acad Sci U S A. 2005 Feb 8;102(6):2129-34

  Authors: Shahab M, Mastronardi C, Seminara SB, Crowley WF, Ojeda SR, Plant TM

  To further study the role of GPR54 signaling in the onset of primate puberty, we used the monkey to examine the ability of kisspeptin-10 to elicit the release of gonadotropin-releasing hormone (GnRH) precociously, and we describe the expression of GPR54 and KiSS-1 in the hypothalamus during the peripubertal period. Agonadal juvenile male monkeys were implanted with a lateral cerebroventricular cannula and a jugular vein catheter. The responsiveness of the juvenile pituitary to endogenous GnRH release was heightened with a chronic pulsatile i.v. infusion of synthetic GnRH before kisspeptin-10 (112-121) injection. Intracerebroventricular (30 microg or 100 microg) or i.v. (100 microg) bolus injections of kisspeptin-10 elicited a robust GnRH discharge, as reflected by luteinizing hormone secretion, which was abolished by pretreatment with a GnRH-receptor antagonist. RNA was isolated from the hypothalamus of agonadal males before (juvenile) and after (pubertal) the pubertal resurgence of pulsatile GnRH release and from juvenile, early pubertal, and midpubertal ovary-intact females. KiSS-1 mRNA levels detected by real-time PCR increased with puberty in both male and female monkeys. In intact females, but not in agonadal males, GPR54 mRNA levels in the hypothalamus increased approximately 3-fold from the juvenile to midpubertal stage. Hybridization histochemistry indicated robust KiSS-1 and GPR54 mRNA expression in the region of the arcuate nucleus. These findings are consistent with the hypothesis that GPR54 signaling by its cognate ligand in the primate hypothalamus may be activated at the end of the juvenile phase of development and may contribute to the pubertal resurgence of pulsatile GnRH release, the central drive for puberty.

  PMID: 15684075 [PubMed - indexed for MEDLINE]

  
  
  
• Kisspeptin activation of gonadotropin releasing hormone neurons and regulation of KiSS-1 mRNA in the male rat.
  

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  Kisspeptin activation of gonadotropin releasing hormone neurons and regulation of KiSS-1 mRNA in the male rat.

  Neuroendocrinology. 2004;80(4):264-72

  Authors: Irwig MS, Fraley GS, Smith JT, Acohido BV, Popa SM, Cunningham MJ, Gottsch ML, Clifton DK, Steiner RA

  The KiSS-1 gene codes for a family of neuropeptides called kisspeptins which bind to the G-protein-coupled receptor GPR54. To assess the possible effects of kisspeptins on gonadotropin secretion, we injected kisspeptin-52 into the lateral cerebral ventricles of adult male rats and found that kisspeptin-52 increased the serum levels of luteinizing hormone (p < 0.05). To determine whether the kisspeptin-52-induced stimulation of luteinizing hormone secretion was mediated by gonadotropin-releasing hormone (GnRH), we pretreated adult male rats with a GnRH antagonist (acyline), then challenged the animals with intracerebroventricularly administered kisspeptin-52. The GnRH antagonist blocked the kisspeptin-52-induced increase in luteinizing hormone. To examine whether kisspeptins stimulate transcriptional activity in GnRH neurons, we administered kisspeptin-52 intracerebroventricularly and found by immunocytochemistry that 86% of the GnRH neurons coexpressed Fos 2 h after the kisspeptin-52 challenge, whereas fewer than 1% of the GnRH neurons expressed Fos following injection of the vehicle alone (p < 0.001). To assess whether kisspeptins can directly act on GnRH neurons, we used double-label in situ hybridization and found that 77% of the GnRH neurons coexpress GPR54 mRNA. Finally, to determine whether KiSS-1 gene expression is regulated by gonadal hormones, we measured KiSS-1 mRNA levels by single-label in situ hybridization in intact and castrated males and found significantly higher levels in the arcuate nucleus of castrates. These results demonstrate that GnRH neurons are direct targets for regulation by kisspeptins and that KiSS-1 mRNA is regulated by gonadal hormones, suggesting that KiSS-1 neurons play an important role in the feedback regulation of gonadotropin secretion.

  PMID: 15665556 [PubMed - indexed for MEDLINE]

  
  
  
• Kisspeptin directly stimulates gonadotropin-releasing hormone release via G protein-coupled receptor 54.
  

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  Kisspeptin directly stimulates gonadotropin-releasing hormone release via G protein-coupled receptor 54.

  Proc Natl Acad Sci U S A. 2005 Feb 1;102(5):1761-6

  Authors: Messager S, Chatzidaki EE, Ma D, Hendrick AG, Zahn D, Dixon J, Thresher RR, Malinge I, Lomet D, Carlton MB, Colledge WH, Caraty A, Aparicio SA

  We have recently described a molecular gatekeeper of the hypothalamic-pituitary-gonadal axis with the observation that G protein-coupled receptor 54 (GPR54) is required in mice and men for the pubertal onset of pulsatile luteinizing hormone (LH) and follicle-stimulating hormone (FSH) secretion to occur. In the present study, we investigate the possible central mode of action of GPR54 and kisspeptin ligand. First, we show that GPR54 transcripts are colocalized with gonadotropin-releasing hormone (GnRH) neurons in the mouse hypothalamus, suggesting that kisspeptin, the GPR54 ligand, may act directly on these neurons. Next, we show that GnRH neurons seem anatomically normal in gpr54-/- mice, and that they show projections to the median eminence, which demonstrates that the hypogonadism in gpr54-/- mice is not due to an abnormal migration of GnRH neurons (as occurs with KAL1 mutations), but that it is more likely due to a lack of GnRH release or absence of GnRH neuron stimulation. We also show that levels of kisspeptin injected i.p., which stimulate robust LH and FSH release in wild-type mice, have no effect in gpr54-/- mice, and therefore that kisspeptin acts directly and uniquely by means of GPR54 signaling for this function. Finally, we demonstrate by direct measurement, that the central administration of kisspeptin intracerebroventricularly in sheep produces a dramatic release of GnRH into the cerebrospinal fluid, with a parallel rise in serum LH, demonstrating that a key action of kisspeptin on the hypothalamo-pituitary-gonadal axis occurs directly at the level of GnRH release. The localization and GnRH release effects of kisspeptin thus define GPR54 as a major control point in the reproductive axis and suggest kisspeptin to be a neurohormonal effector.

  PMID: 15665093 [PubMed - indexed for MEDLINE]

  
  
  
• Effects of KiSS-1 peptide, the natural ligand of GPR54, on follicle-stimulating hormone secretion in the rat.
  

  Effects of KiSS-1 peptide, the natural ligand of GPR54, on follicle-stimulating hormone secretion in the rat.

  Endocrinology. 2005 Apr;146(4):1689-97

  Authors: Navarro VM, Castellano JM, Fernández-Fernández R, Tovar S, Roa J, Mayen A, Barreiro ML, Casanueva FF, Aguilar E, Dieguez C, Pinilla L, Tena-Sempere M

  KiSS-1 was originally identified as a metastasis suppressor gene encoding an array of structurally related peptides, namely kisspeptins, which acting through the G protein-coupled receptor GPR54 are able to inhibit tumor progression. Unexpectedly, a reproductive facet of this newly discovered system has recently arisen, and characterization of the role of the KiSS-1/GPR54 system in the neuroendocrine control of gonadotropin secretion has been initiated. However, such studies have been so far mostly restricted to LH, and very little is known about the actual contribution of this system in the regulation of FSH release. To address this issue, the effects of KiSS-1 peptide on FSH secretion were monitored in vivo and in vitro under different experimental conditions. Intracerebroventricular administration of KiSS-1 peptide significantly stimulated FSH secretion in prepubertal and adult rats. Yet, dose-response analyses in vivo demonstrated an ED(50) value for the FSH-releasing effects of KiSS-1 of 400 pmol, i.e. approximately 100-fold higher than that of LH. In addition, systemic (ip and iv) injection of KiSS-1 significantly stimulated FSH secretion in vivo. However, KiSS-1 failed to elicit basal FSH release directly at the pituitary level, although it moderately enhanced GnRH-stimulated FSH secretion in vitro. Finally, mechanistic studies revealed that the ability of KiSS-1 to elicit FSH secretion was abolished by the blockade of endogenous GnRH actions, but it was persistently observed in different models of leptin insufficiency and after blockade of endogenous excitatory amino acid and nitric oxide pathways, i.e. relevant signals in the neuroendocrine control of gonadotropin secretion. In summary, our results extend previous recent observations on the role of KiSS-1 in the control of LH secretion and provide solid evidence for a stimulatory effect of KiSS-1 on FSH release, acting at central level. Overall, it is proposed that the KiSS-1/GPR54 system is a novel, pivotal downstream element in the neuroendocrine network governing gonadotropin secretion.

  PMID: 15637288 [PubMed - indexed for MEDLINE]

  
  
  
• Two novel missense mutations in g protein-coupled receptor 54 in a patient with hypogonadotropic hypogonadism.
  

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  Two novel missense mutations in g protein-coupled receptor 54 in a patient with hypogonadotropic hypogonadism.

  J Clin Endocrinol Metab. 2005 Mar;90(3):1849-55

  Authors: Semple RK, Achermann JC, Ellery J, Farooqi IS, Karet FE, Stanhope RG, O'rahilly S, Aparicio SA

  It has recently been shown that loss-of-function mutations of the G protein-coupled receptor (GPR)54 lead to isolated hypogonadotropic hypogonadism (IHH) in mice and humans. Such mutations are thought to be rare, even within the clinical IHH population, and only a handful of alleles have been described, making further screening of IHH populations imperative. We examined the genes encoding GPR54 and its putative endogenous ligand, kisspeptin-1, for mutations in a cohort of 30 patients with normosmic HH or delayed puberty. One subject with HH, of mixed Turkish-Cypriot and Afro-Caribbean ancestry, was found to be a compound heterozygote for two previously undescribed missense mutations in GPR54: cysteine 223 to arginine (C223R) in the fifth transmembrane helix and arginine 297 to leucine (R297L) in the third extracellular loop. Assessed in vitro using a previously described sensitive signaling assay in cells stably expressing GPR54, the C223R variant was found to exhibit profoundly impaired signaling, whereas the R297L variant showed a mild reduction in ligand-stimulated activity across the ligand dose range. These novel mutations provide further evidence that human HH may be caused by loss-of-function mutations in GPR54.

  PMID: 15598687 [PubMed - indexed for MEDLINE]

  
  
  
• Activation of GPR54 promotes cell cycle arrest and apoptosis of human tumor cells through a specific transcriptional program not shared by other Gq-coupled receptors.
  

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  Activation of GPR54 promotes cell cycle arrest and apoptosis of human tumor cells through a specific transcriptional program not shared by other Gq-coupled receptors.

  Biochem Biophys Res Commun. 2005 Jan 21;326(3):677-86

  Authors: Becker JA, Mirjolet JF, Bernard J, Burgeon E, Simons MJ, Vassart G, Parmentier M, Libert F

  GPR54 is a receptor for peptides derived from the metastasis suppressor gene KiSS-1. To investigate the intracellular mechanisms involved in the reduction of the metastatic potential of MDA-MB-435S cells expressing GPR54, a time course stimulation by kisspeptin-10 over a period of 25 h was performed using cDNA microarrays. Comparison with the bradykinin B(2) receptor revealed a distinct pattern of gene regulation despite a common coupling to the G(q/11) class of G-proteins. Inhibitors of PLC and PK-C abolished the transcriptional regulation of all tested genes, while an inhibitor of p42/44 affected a subset of genes controlled both by GPR54 and B(2). Among the genes specifically up-regulated by GPR54, we found several proapoptotic genes. Stimulation of GPR54 promoted apoptosis while no significant change was observed after B(2) receptor activation. Our results suggest that the metastasis suppressor properties of GPR54 are mediated in part by cell cycle arrest and induction of apoptosis in malignant cells.

  PMID: 15596153 [PubMed - indexed for MEDLINE]

  
  
  
• KiSS-1 expression and metastin-like immunoreactivity in the rat brain.
  

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  KiSS-1 expression and metastin-like immunoreactivity in the rat brain.

  J Comp Neurol. 2005 Jan 17;481(3):314-29

  Authors: Brailoiu GC, Dun SL, Ohsawa M, Yin D, Yang J, Chang JK, Brailoiu E, Dun NJ

  Metastin, the gene product of metastasis suppressor gene KiSS-1, is the endogenous ligand for the G-protein-coupled receptor GPR54 (or AXOR12, or OT7T175). The expression of KiSS-1 gene and peptide and the distribution of metastin were studied in the rat central nervous system by reverse transcriptase-polymerase chain reaction, Western blotting, and immunohistochemical methods. KiSS-1 gene and peptide expression was higher in the hypothalamus than in the brainstem and spinal cord. In the brain, metastin-like immunoreactivity (irMT) was found mainly in three groups of cells: dorsomedial hypothalamic nucleus, nucleus of the solitary tract, and caudal ventrolateral medulla. Immunoreactive fibers of varying density were noted in bed nucleus of stria terminalis, septal nuclei, nucleus accumbens, caudate putamen, diagonal band, amygdala, hypothalamus, zona incerta, thalamus, periaqueductal gray, raphe nuclei, lateral parabrachial nucleus, locus coeruleus, spinal trigeminal tract, rostral ventrolateral medulla, and medullary reticular nucleus. Preabsorption of the antiserum with metastin peptide fragment (45-54)-NH2 (1 microg/ml) resulted in no staining in any of the sections. The biological activity of metastin was assessed by monitoring intracellular calcium [Ca2+]i in cultured hippocampal neurons, which are known to express GPR54. Metastin increased [Ca2+]i in a population of cultured hippocampal neurons. The results show that metastin is biologically active in rat central neurons, and its anatomical distribution suggests a possible role in nociception and autonomic and neuroendocrine functions.

  PMID: 15593369 [PubMed - indexed for MEDLINE]

  
  
  
• GPR54 and puberty.
  

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  GPR54 and puberty.

  Trends Endocrinol Metab. 2004 Nov;15(9):448-53

  Authors: Colledge WH

  At puberty, pulsatile secretion of hormones initiates sexual maturation of the gonads. The G-protein-coupled receptor GPR54 is crucially involved in the initiation of puberty, along with its ligand metastin. Mice lacking GPR54 fail to undergo puberty and have immature reproductive organs and low levels of sex steroids and gonadotrophic hormones, but have normal levels of gonadotrophin-releasing hormone in the hypothalamus. In humans, several cases of hypogonadism have been ascribed to mutations in GPR54. Production of metastin and, to a lesser extent, GPR54 are negatively regulated by testosterone and oestrogen, and injecting GPR54 ligands can increase hormone secretion in rodents. Thus, GPR54 is required for normal functioning of the hypothalamic-pituitary-gonadal axis, probably at the level of gonadotrophin-releasing-hormone secretion.

  PMID: 15519892 [PubMed - indexed for MEDLINE]

  
  
  
• Central and peripheral administration of kisspeptin-10 stimulates the hypothalamic-pituitary-gonadal axis.
  

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  Central and peripheral administration of kisspeptin-10 stimulates the hypothalamic-pituitary-gonadal axis.

  J Neuroendocrinol. 2004 Oct;16(10):850-8

  Authors: Thompson EL, Patterson M, Murphy KG, Smith KL, Dhillo WS, Todd JF, Ghatei MA, Bloom SR

  Kisspeptin is the peptide product of the KiSS-1 gene and the endogenous agonist for the GPR54 receptor. Recent evidence suggests the kisspeptin/GPR54 system is a key regulator of the reproductive system. We examined the effect of intracerebroventricular (i.c.v.) and peripheral administration of the active kisspeptin fragment, kisspeptin-10, on circulating gonadotrophins and total testosterone levels in adult male rats. The effect of kisspeptin-10 in vitro on the release of hypothalamic peptides from hypothalamic explants and gonadotrophins from anterior pituitary fragments was also determined. The i.c.v. administration of kisspeptin-10 dose-dependently increased plasma luteinizing hormone (LH) and increased plasma follicle stimulating hormone (FSH) and total testosterone at 60 min postinjection. In a separate study investigating the time course of this response, i.c.v. administered kisspeptin-10 (3 nmol) significantly increased plasma LH at 10, 20 and 60 min, FSH at 60 min and total testosterone at 20 and 60 min postinjection. Kisspeptin-10 stimulated the release of luteinizing hormone-releasing hormone (LHRH) from in vitro hypothalamic explants. Peripheral administration of kisspeptin-10 increased plasma LH, FSH and total testosterone. However, doses of 100-1000 nM kisspeptin-10 did not influence LH or FSH release from pituitary fragments in vitro. Kisspeptin therefore potently stimulates the hypothalamic-pituitary-gonadal axis. These effects are likely to be mediated via the hypothalamic LHRH system.

  PMID: 15500545 [PubMed - indexed for MEDLINE]

  
  
  
• Advanced vaginal opening and precocious activation of the reproductive axis by KiSS-1 peptide, the endogenous ligand of GPR54.
  

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  Advanced vaginal opening and precocious activation of the reproductive axis by KiSS-1 peptide, the endogenous ligand of GPR54.

  J Physiol. 2004 Dec 1;561(Pt 2):379-86

  Authors: Navarro VM, Fernández-Fernández R, Castellano JM, Roa J, Mayen A, Barreiro ML, Gaytan F, Aguilar E, Pinilla L, Dieguez C, Tena-Sempere M

  The awakening of the gonadotrophic axis at puberty is the end-point of a complex cascade of sex developmental events that leads to the attainment of reproductive capacity. Recently, loss-of-function mutations of the gene encoding GPR54, the putative receptor for the KiSS-1-derived peptide metastin, have been linked to hypogonadotrophic hypogonadism, both in rodents and humans. However, the actual role of the KiSS-1/GPR54 system in the timing of puberty onset remains unexplored. We report herein that chronic central administration of KiSS-1 peptide to immature female rats induced the precocious activation of the gonadotrophic axis, as estimated by advanced vaginal opening, elevated uterus weight, and increased serum levels of luteinizing hormone (LH) and oestrogen. The central effect of KiSS-1 upon LH release appeared to be mediated via the hypothalamic LH-releasing hormone. In contrast, despite the well-documented permissive role of body fat stores and the adipocyte-derived hormone leptin in puberty maturation, acute activation of the gonadotrophic axis by KiSS-1 was persistently observed in pubertal animals under food deprivation, after central immunoneutralization of leptin, and in a model of leptin resistance. Overall, the present results, together with our recent data on maximum expression of KiSS-1 and GPR54 genes in the hypothalamus at puberty, provide novel evidence for a role of the KiSS-1 system as a downstream element in the hypothalamic network triggering the onset of puberty.

  PMID: 15486019 [PubMed - indexed for MEDLINE]

  
  
  
• Characterization of the potent luteinizing hormone-releasing activity of KiSS-1 peptide, the natural ligand of GPR54.
  

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  Characterization of the potent luteinizing hormone-releasing activity of KiSS-1 peptide, the natural ligand of GPR54.

  Endocrinology. 2005 Jan;146(1):156-63

  Authors: Navarro VM, Castellano JM, Fernández-Fernández R, Tovar S, Roa J, Mayen A, Nogueiras R, Vazquez MJ, Barreiro ML, Magni P, Aguilar E, Dieguez C, Pinilla L, Tena-Sempere M

  Loss-of-function mutations of the gene encoding GPR54, the putative receptor for the KiSS-1-derived peptide metastin, have been recently associated with hypogonadotropic hypogonadism, in both rodents and humans. Yet the actual role of the KiSS-1/GPR54 system in the neuroendocrine control of gonadotropin secretion remains largely unexplored. To initiate such analysis, the effects of KiSS-1 peptide on LH secretion were monitored using in vivo and in vitro settings under different experimental conditions. Central intracerebroventricular administration of KiSS-1 peptide potently elicited LH secretion in vivo over a range of doses from 10 pmol to 1 nmol. The effect of centrally injected KiSS-1 appeared to be mediated via the hypothalamic LHRH. However, no effect of central administration of KiSS-1 was detected on relative LHRH mRNA levels. Likewise, systemic (i.p. and i.v.) injection of KiSS-1 markedly stimulated LH secretion. This effect was similar in terms of maximum response to that of central administration of KiSS-1 and might be partially attributed to its ability to stimulate LH secretion directly at the pituitary. Finally, the LH-releasing activity of KiSS-1 was persistently observed after blockade of endogenous excitatory amino acid and nitric oxide pathways, i.e. relevant neurotransmitters in the neuroendocrine control of LH secretion. In summary, our results provide solid evidence for a potent stimulatory effect of KiSS-1 on LH release, acting at central levels (likely the hypothalamus) and eventually at the pituitary, and further document a novel role of the KiSS-1/GPR54 system as a relevant downstream element in the neuroendocrine network governing LH secretion.

  PMID: 15375028 [PubMed - indexed for MEDLINE]

  
  
  
• Downregulation of KiSS-1 expression is responsible for tumor invasion and worse prognosis in gastric carcinoma.
  

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  Downregulation of KiSS-1 expression is responsible for tumor invasion and worse prognosis in gastric carcinoma.

  Int J Cancer. 2004 Oct 10;111(6):868-72

  Authors: Dhar DK, Naora H, Kubota H, Maruyama R, Yoshimura H, Tonomoto Y, Tachibana M, Ono T, Otani H, Nagasue N

  KiSS-1 is a promising candidate tumor-suppressor gene and may play a key role in the metastatic cascade. The expression profile and the role of KiSS-1 in cancer progression are largely unknown in most of the cancers, including gastric cancer. In this study, KiSS-1 expression was evaluated by RNase protection assay and localization was done by in situ hybridization in 40 gastric cancers and their adjacent normal gastric mucosa. For comparison with clinicopathologic characteristics and patient prognosis, all patients were divided into 2 groups having high and low KiSS-1 expression by using the median as the cutoff value of KiSS-1 expression as determined by the RNase protection assay. Gastric cancers with low KiSS-1 had frequent venous invasion, distant metastasis and tumor recurrence. Accordingly, patients with low KiSS-1-expressing tumors had a significantly worse overall and disease-free survival. In multivariate analysis, KiSS-1 became the strongest independent prognostic factor among the conventional prognosticators for gastric cancer patients. Collectively, these findings suggest that KiSS-1 may play a crucial role in gastric cancer invasion and could be a useful target for therapeutic intervention.

  PMID: 15300798 [PubMed - indexed for MEDLINE]

  
  
  
• Developmental and hormonally regulated messenger ribonucleic acid expression of KiSS-1 and its putative receptor, GPR54, in rat hypothalamus and potent luteinizing hormone-releasing activity of KiSS-1 peptide.
  

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  Developmental and hormonally regulated messenger ribonucleic acid expression of KiSS-1 and its putative receptor, GPR54, in rat hypothalamus and potent luteinizing hormone-releasing activity of KiSS-1 peptide.

  Endocrinology. 2004 Oct;145(10):4565-74

  Authors: Navarro VM, Castellano JM, Fernández-Fernández R, Barreiro ML, Roa J, Sanchez-Criado JE, Aguilar E, Dieguez C, Pinilla L, Tena-Sempere M

  The gonadotropic axis is centrally controlled by a complex regulatory network of excitatory and inhibitory signals that is activated at puberty. Recently, loss of function mutations of the gene encoding G protein-coupled receptor 54 (GPR54), the putative receptor for the KiSS-1-derived peptide metastin, have been associated with lack of puberty onset and hypogonadotropic hypogonadism. Yet the pattern of expression and functional role of the KiSS-1/GPR54 system in the rat hypothalamus remain unexplored to date. In the present work, expression analyses of KiSS-1 and GPR54 genes were conducted in different physiological and experimental settings, and the effects of central administration of KiSS-1 peptide on LH release were assessed in vivo. Persistent expression of KiSS-1 and GPR54 mRNAs was detected in rat hypothalamus throughout postnatal development, with maximum expression levels at puberty in both male and female rats. Hypothalamic expression of KiSS-1 and GPR54 genes changed throughout the estrous cycle and was significantly increased after gonadectomy, a rise that was prevented by sex steroid replacement both in males and females. Moreover, hypothalamic expression of the KiSS-1 gene was sensitive to neonatal imprinting by estrogen. From a functional standpoint, intracerebroventricular administration of KiSS-1 peptide induced a dramatic increase in serum LH levels in prepubertal male and female rats as well as in adult animals. In conclusion, we provide novel evidence of the developmental and hormonally regulated expression of KiSS-1 and GPR54 mRNAs in rat hypothalamus and the ability of KiSS-1 peptide to potently stimulate LH secretion in vivo. Our current data support the contention that the hypothalamic KiSS-1/GPR54 system is a pivotal factor in central regulation of the gonadotropic axis at puberty and in adulthood.

  PMID: 15242985 [PubMed - indexed for MEDLINE]

  
  
  
• Peripheral administration of metastin induces marked gonadotropin release and ovulation in the rat.
  

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  Peripheral administration of metastin induces marked gonadotropin release and ovulation in the rat.

  Biochem Biophys Res Commun. 2004 Jul 23;320(2):383-8

  Authors: Matsui H, Takatsu Y, Kumano S, Matsumoto H, Ohtaki T

  Metastin is a novel peptide that has been isolated from the human placenta as the cognate ligand of the G-protein-coupled receptor OT7T175 (or GPR54). However, its physiological functions have not yet been fully investigated. In the present study, we show that subcutaneous administration of metastin increased the plasma levels of gonadotropins (follicle-stimulating hormone and luteinizing hormone) and induced ovulation in prepubertal female rats that had been pretreated with pregnant mare serum gonadotropin to induce follicle maturation. Furthermore, metastin administration drastically increased the plasma levels of gonadotropins in male rats. This action was abolished by pretreatment with a GnRH antagonist, and was accompanied by induction of c-Fos immunoreactivity in GnRH neurons. These results suggest that s.c. administered metastin induces the release of gonadotropin via activation of the hypothalamic GnRH neurons.

  PMID: 15219839 [PubMed - indexed for MEDLINE]

  
  
  
• A role for kisspeptins in the regulation of gonadotropin secretion in the mouse.
  

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  A role for kisspeptins in the regulation of gonadotropin secretion in the mouse.

  Endocrinology. 2004 Sep;145(9):4073-7

  Authors: Gottsch ML, Cunningham MJ, Smith JT, Popa SM, Acohido BV, Crowley WF, Seminara S, Clifton DK, Steiner RA

  Kisspeptins are products of the KiSS-1 gene, which bind to a G protein-coupled receptor known as GPR54. Mutations or targeted disruptions in the GPR54 gene cause hypogonadotropic hypogonadism in humans and mice, suggesting that kisspeptin signaling may be important for the regulation of gonadotropin secretion. To examine the effects of kisspeptin-54 (metastin) and kisspeptin-10 (the biologically active C-terminal decapeptide) on gonadotropin secretion in the mouse, we administered the kisspeptins directly into the lateral cerebral ventricle of the brain and demonstrated that both peptides stimulate LH secretion. Further characterization of kisspeptin-54 demonstrated that it stimulated both LH and FSH secretion, at doses as low as 1 fmol; moreover, this effect was shown to be blocked by pretreatment with acyline, a potent GnRH antagonist. To learn more about the functional anatomy of kisspeptins, we mapped the distribution of KiSS-1 mRNA in the hypothalamus. We observed that KiSS-1 mRNA is expressed in areas of the hypothalamus implicated in the neuroendocrine regulation of gonadotropin secretion, including the anteroventral periventricular nucleus, the periventricular nucleus, and the arcuate nucleus. We conclude that kisspeptin-GPR54 signaling may be part of the hypothalamic circuitry that governs the hypothalamic secretion of GnRH.

  PMID: 15217982 [PubMed - indexed for MEDLINE]

  
  
  
• Expression of KiSS-1, a metastasis suppressor gene, in trophoblast giant cells of the rat placenta.
  

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  Expression of KiSS-1, a metastasis suppressor gene, in trophoblast giant cells of the rat placenta.

  Biochim Biophys Acta. 2004 May 25;1678(2-3):102-10

  Authors: Terao Y, Kumano S, Takatsu Y, Hattori M, Nishimura A, Ohtaki T, Shintani Y

  Metastin is encoded by a putative human metastasis suppressor gene KiSS-1, and is the cognate ligand of a G-protein-coupled receptor designated OT7T175. To study the physiological function(s) of metastin, we cloned rat and mouse KiSS-1 cDNAs both encoding 130-amino acid KiSS-1 proteins. Sequence analysis suggested that processing of the rat and mouse KiSS-1 proteins produces 52-amino-acid peptides, each with an amidated carboxyl terminal and with a single possible disulfide bond, corresponding to rat and mouse metastins. The carboxyl-terminal sequence of metastin, known to be essential for functional receptor interaction, was found to be highly conserved among humans and rodents. Real-time PCR analysis indicated that rat KiSS-1 mRNA showed the highest expression level in the cecum and colon. Since KiSS-1 mRNA and metastin are known to be abundant in human placenta, we further studied the localization of KiSS-1 and OT7T175 mRNAs in rat placenta by in situ hybridization. KiSS-1 and OT7T175 mRNAs were specifically detected in trophoblast giant cells at embryonic day 12.5, and the transcripts in the cells gradually decreased during placental maturation. These results suggest that metastin/OT7T175 signaling may participate in implantation of the mammalian embryo, placenta formation, and maintenance of pregnancy.

  PMID: 15157736 [PubMed - indexed for MEDLINE]

  
  
  
• [GnRH deficiency: new insights from genetics]
  

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  [GnRH deficiency: new insights from genetics]

  J Soc Biol. 2004;198(1):80-7

  Authors: Kottler ML, Hamel A, Malville E, Richard N

  The acquisition of a sexually dimorphic phenotype is a critical event in mammalian development. Hypogonadotropic hypogonadism (HH) results from impaired secretion of GnRH. The patients display with delayed puberty, micropenis and cryptorchidism in the male reflecting gonadotropin insufficiency, and amenorrhea in the female. Kallmann's syndrome (KS) is defined by the association of HH and anosmia or hyposmia (absent smelling sense). Segregation analysis in familial cases has demonstrated diverse inheritance patterns, suggesting the existence of several genes regulating GnRH secretion. The X-linked form of the disease was associated with a genetic defect in the KALI gene located on the Xp22.3 region. KAL1 gene encodes an extracellular matrix glycoprotein anosmin-1, which facilitates neuronal growth and migration. Abnormalities in the migratory processes of the GnRH neurons with the olfactory neurons explain the association of HH with anosmia. Recently, mutations in the FGF recepteur 1 (FGFR1) gene were found in KS with autosomal dominant mode of inheritance. The role of FGFR1 in the function of reproduction requires further investigation. Besides HH with anosmia, there are isolated HH (IHH). No human GnRH mutations have been reported although hypogonadal mice due to a GnRH gene deletion exist. In patients with idiopathic HH and without anosmia an increasing number of GnRH receptor (GnRHR) mutations have been described which represent about 50% of familial cases. The clinical features are highly variable and there is a good relationship between genotype and phenotype. A complete loss of function is associated with the most severe phenotype with resistance to pulsatile GnRH treatment, absence of puberty and cryptorchidism in the male. In contrast, milder loss of function mutations causes incomplete failure of pubertal development. The preponderant role of GnRH in the secretion of LH by the gonadotrophs explains the difference of the phenotype between male and female with partial GnRH resistance. Affected females can have spontaneous telarche and normal breast development while affected males exhibit no pubertal development but normal testis volume, a feature described as "fertile-eunuch". High-dose pulsatile GnRH has been used to induce ovulation. Another gene, called GPR54, responsible for idiopathic HH has been recently described by segregation analysis in two different consanguineous families. The GPR54 gene is an orphan receptor, and its putative ligand is the product of the KISS-1 gene, called metastine. Their roles in the function of reproduction are still unknown.

  PMID: 15146960 [PubMed - indexed for MEDLINE]

  
  
  
• In vivo and in situ modulation of the expression of genes involved in metastasis and angiogenesis in a patient treated with topical imiquimod for melanoma skin metastases.
  

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  In vivo and in situ modulation of the expression of genes involved in metastasis and angiogenesis in a patient treated with topical imiquimod for melanoma skin metastases.

  Br J Dermatol. 2004 Apr;150(4):761-7

  Authors: Hesling C, D'Incan M, Mansard S, Franck F, Corbin-Duval A, Chèvenet C, Déchelotte P, Madelmont JC, Veyre A, Souteyrand P, Bignon YJ

  There is a growing body of evidence to support the efficacy of topical imiquimod in the treatment of primary skin carcinomas. Conflicting data exist concerning the use of imiquimod for the treatment of skin melanoma metastases. To date, only the impact of imiquimod on cytokines involved in immunological processes has been studied extensively. We report a woman successfully treated with imiquimod (once daily for 8 weeks) for skin melanoma metastases in whom we investigated the expression of molecules involved in metastasis and angiogenesis. Before and after treatment, a skin lesion was biopsied and the expression of the following molecules was investigated using real-time reverse transcription-polymerase chain reaction: matrix metalloproteinase (MMP)-1, 2 and 9 and their inhibitors KiSS-1 and tissue inhibitor of metalloproteinase (TIMP)-1, vascular endothelial growth factor (VEGF), fibroblast growth factor-2, and angiogenesis inhibitors (thrombospondin-1 and 2). Interferon (IFN)-alpha was also investigated as an in vivo marker of imiquimod activity. IFN-alpha was upregulated by the treatment. Under imiquimod, the following molecules were upregulated: TIMP-1, KiSS-1 and MMP-1. MMP-2 expression was not modified. MMP-9 expression was dramatically decreased. The expression of angiogenesis inhibitors was slightly increased but VEGF expression remained at a basal level. These results suggest that imiquimod could downregulate metastasis invasion and angiogenesis. However, these data were obtained at a transcriptional level and from a single case, and further investigations should include migration assays and additional cases in order to confirm that imiquimod may be safely used for treatment of melanoma metastases.

  PMID: 15099376 [PubMed - indexed for MEDLINE]

  
  
  
• Kisspeptin-10, a KiSS-1/metastin-derived decapeptide, is a physiological invasion inhibitor of primary human trophoblasts.
  

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  Kisspeptin-10, a KiSS-1/metastin-derived decapeptide, is a physiological invasion inhibitor of primary human trophoblasts.

  J Cell Sci. 2004 Mar 15;117(Pt 8):1319-28

  Authors: Bilban M, Ghaffari-Tabrizi N, Hintermann E, Bauer S, Molzer S, Zoratti C, Malli R, Sharabi A, Hiden U, Graier W, Knöfler M, Andreae F, Wagner O, Quaranta V, Desoye G

  Trophoblast invasion of the uterine extracellular matrix, a critical process of human implantation and essential for fetal development, is a striking example of controlled invasiveness. To identify molecules that regulate trophoblast invasion, mRNA signatures of trophoblast cells isolated from first trimester (high invasiveness) and term placentae (no/low invasiveness) were compared using U95A GeneChip microarrays yielding 220 invasion/migration-related genes. In this 'invasion cluster', KiSS-1 and its G-protein-coupled receptor KiSS-1R were expressed at higher levels in first trimester trophoblasts than at term of gestation. Receptor and ligand mRNA and protein were localized to the trophoblast compartment. In contrast to KiSS-1, which is only expressed in the villous trophoblast, KiSS-1R was also found in the extravillous trophoblast, suggesting endocrine/paracrine activation mechanisms. The primary translation product of KiSS-1 is a 145 amino acid polypeptide (Kp-145), but shorter kisspeptins (Kp) with 10, 13, 14 or 54 amino acid residues may be produced. We identified Kp-10, a dekapeptide derived from the primary translation product, in conditioned medium of first trimester human trophoblast. Kp-10, but not other kisspeptins, increased intracellular Ca(2+) levels in isolated first trimester trophoblasts. Kp-10 inhibited trophoblast migration in an explant as well as transwell assay without affecting proliferation. Suppressed motility was paralleled with suppressed gelatinolytic activity of isolated trophoblasts. These results identified Kp-10 as a novel paracrine/endocrine regulator in fine-tuning trophoblast invasion generated by the trophoblast itself.

  PMID: 15020672 [PubMed - indexed for MEDLINE]

  
  
  
• Metastin and its variant forms suppress migration of pancreatic cancer cells.
  

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  Metastin and its variant forms suppress migration of pancreatic cancer cells.

  Biochem Biophys Res Commun. 2004 Feb 27;315(1):85-92

  Authors: Masui T, Doi R, Mori T, Toyoda E, Koizumi M, Kami K, Ito D, Peiper SC, Broach JR, Oishi S, Niida A, Fujii N, Imamura M

  Metastin, a post-translationally modified variant of KiSS1, was recently identified as an endogenous peptide agonist for a novel G-protein coupled receptor, hOT7T175 (AXOR12, GPR54). In this study, we analyzed the role of KiSS1 and hOT7T175 in both pancreatic cancer tissues and pancreatic cancer cell lines. Furthermore, we synthesized novel short variant forms of metastin and tested the inhibitory effect of those variants on in vitro cell functions that are relevant to metastasis. Pancreatic cancer tissues showed significantly lower expression of KiSS1 mRNA than normal tissues (p=0.018), while cancer tissues showed significantly higher expression of hOT7T175 mRNA than normal pancreatic tissues (p=0.027). In human pancreatic cancer cell lines, KiSS1 mRNA was highly expressed in 2 out of 6 pancreatic cancer cell lines, while hOT7T175 mRNA was expressed in all cell lines at various degrees. PANC-1 cells showed the highest expression of hOT7T175. Exogenous metastin did not suppress cell proliferation but significantly reduced the in vitro migration of PANC-1 cells (p<0.01). Metastin induced activation of ERK1 in PANC-1 and AsPC-1 cells. Finally, we synthesized 3 novel short variant forms of metastin, FM053a2TFA, FM059a2TFA, and FM052a4TFA. These metastin variants significantly suppressed the migration of PANC-1 cells and activated ERK1. These data suggest that the metastin receptor, hOT7T175, is one of the promising targets for suppression of metastasis, and that small metastin variants could be an anti-metastatic agent to pancreatic cancer.

  PMID: 15013429 [PubMed - indexed for MEDLINE]

  
  
  
• Clinical significance of the loss of KiSS-1 and orphan G-protein-coupled receptor (hOT7T175) gene expression in esophageal squamous cell carcinoma.
  

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  Clinical significance of the loss of KiSS-1 and orphan G-protein-coupled receptor (hOT7T175) gene expression in esophageal squamous cell carcinoma.

  Clin Cancer Res. 2004 Feb 15;10(4):1379-83

  Authors: Ikeguchi M, Yamaguchi K, Kaibara N

  PURPOSE: Lymph node metastasis is the most important predictor of prognosis in esophageal squamous cell carcinoma (ESCC). Recently, KiSS-1 was cloned as a human metastasis suppressor gene, and an orphan G-protein-coupled receptor (hOT7T175) was identified as the endogenous receptor of the KiSS-1 product. However, the clinical importance of KiSS-1 and hOT7T175 gene expression in ESCC remains unclear. EXPERIMENTAL DESIGN: In this study, total RNA was extracted from tumors and noncancerous epithelia of 71 patients with ESCC who underwent surgical esophageal resection. The expression levels of KiSS-1, hOT7T175, and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNAs were analyzed quantitatively by real-time reverse transcription-PCR and compared with the clinical findings. RESULTS: The mean KiSS-1:GAPDH and hOT7T175:GAPDH ratios of the tumors were 1.2 and 0.3 and were at the same levels as those in the noncancerous epithelia. The loss of KiSS-1 and hOT7T175 gene expression was detected in 38% and 61% of tumors. Loss of KiSS-1 and/or hOT7T175 gene expression was not correlated with tumor size or degree of tumor invasion but was found to be a significant predictor of lymph node metastasis. CONCLUSIONS: Loss of KiSS-1 or hOT7T175 gene expression may be an important biomarker for detection of lymph node metastasis in ESCC.

  PMID: 14977840 [PubMed - indexed for MEDLINE]

  
  
  
• The KiSS-1 receptor GPR54 is essential for the development of the murine reproductive system.
  

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  The KiSS-1 receptor GPR54 is essential for the development of the murine reproductive system.

  Biochem Biophys Res Commun. 2003 Dec 26;312(4):1357-63

  Authors: Funes S, Hedrick JA, Vassileva G, Markowitz L, Abbondanzo S, Golovko A, Yang S, Monsma FJ, Gustafson EL

  GPR54 is a G-protein-coupled receptor that displays a high percentage of identity in the transmembrane domains with the galanin receptors. The ligand for GPR54 has been identified as a peptide derived from the KiSS-1 gene. KiSS-1 has been shown to have anti-metastatic effects, suggesting that KiSS-1 or its receptor represents a potential therapeutic target. To further our understanding of the physiological function of this receptor, we have generated a mutant mouse line with a targeted disruption of the GPR54 receptor (GPR54 -/-). The analysis of the GPR54 mutant mice revealed developmental abnormalities of both male and female genitalia and histopathological changes in tissues which normally contain sexually dimorphic features. These data suggest a role for GPR54/KiSS-1 in normal sexual development, and indicate that study of the GPR54 mutant mice may provide valuable insights into human reproductive syndromes.

  PMID: 14652023 [PubMed - indexed for MEDLINE]

  
  
  
• [Research on functional localization and cloning of metastasis suppressor genes]
  

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  [Research on functional localization and cloning of metastasis suppressor genes]

  Ai Zheng. 2003 Nov;22(11):1237-40

  Authors: Liu H, Ye SL

  Metastasis is the most lethal attribute of cancer, which severely affects the effectiveness and prognosis of cancer patients. The discovery of metastasis suppressor genes will provide important clues for the predictive diagnosis and interferential therapies of metastasis. However, there have been few metastasis suppressor genes discovered till now. And this kind of research has not been reported domestically yet. In order to promote this research, this paper reviewed the theoretical principles and technical approaches for the functional localization and cloning strategy for metastasis suppressor genes, which mainly include microcell mediated chromosome transfer, PCR analysis of site tagged sites, and spontaneous metastasis analysis. The metastasis suppressor genes, KAI-1, KiSS-1, MKK4, and BRMS1, discovered by this technique and the application of this technique in prostate cancer, melanoma, and liver cancer are also reviewed.

  PMID: 14613661 [PubMed - indexed for MEDLINE]

  
  
  
• Quantitative reverse transcriptase polymerase chain reaction analysis for KiSS-1 and orphan G-protein-coupled receptor (hOT7T175) gene expression in hepatocellular carcinoma.
  

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  Quantitative reverse transcriptase polymerase chain reaction analysis for KiSS-1 and orphan G-protein-coupled receptor (hOT7T175) gene expression in hepatocellular carcinoma.

  J Cancer Res Clin Oncol. 2003 Sep;129(9):531-5

  Authors: Ikeguchi M, Hirooka Y, Kaibara N

  PURPOSE: KiSS-1 has been cloned as a human metastasis suppressor gene and an orphan G-protein-coupled receptor (hOT7T175) identified as the endogenous receptor of the KiSS-1 product. In the present study, we evaluated the clinical importance of KiSS-1 and hOT7T175 gene expression in hepatocellular carcinoma (HCC). METHODS: The expression levels of KiSS-1, hOT7T175 and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) messenger RNAs (mRNAs) were analyzed quantitatively by real-time reverse transcriptase polymerase chain reaction (RT-PCR) in 60 surgically resected HCCs. The KiSS-1/GAPDH and hOT7T175/GAPDH ratios of tumors were compared with clinicopathological findings. RESULTS: Loss of KiSS-1 mRNA expression was not detected in HCCs. The mean KiSS-1/GAPDH ratio did not change between non-cancerous cirrhotic livers and carcinomas. On the other hand, the average hOT7T175/GAPDH ratios increased from non-cancerous livers (0.08) to carcinomas (0.48). Overexpression of KiSS-1 and hOT7T175 genes was recognized in 6 tumors, which were in an advanced stage and showed poor survival. CONCLUSION: Overexpression of KiSS-1 and hOT7T175 genes was frequently observed and correlated with HCC progression; thus, the possibility that overexpressed KiSS-1 and hOT7T175 peptides mediate growth signals into cancer cells in HCCs is suggested.

  PMID: 12898236 [PubMed - indexed for MEDLINE]

  
  
  
• Cleavage of metastasis suppressor gene product KiSS-1 protein/metastin by matrix metalloproteinases.
  

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  Cleavage of metastasis suppressor gene product KiSS-1 protein/metastin by matrix metalloproteinases.

  Oncogene. 2003 Jul 24;22(30):4617-26

  Authors: Takino T, Koshikawa N, Miyamori H, Tanaka M, Sasaki T, Okada Y, Seiki M, Sato H

  A human placenta cDNA library was screened by the expression cloning method for gene products that interact with matrix metalloproteinases (MMPs), and we isolated a cDNA whose product formed a stable complex with pro-MMP-2 and pro-MMP-9. The cDNA encoded the metastasis suppressor gene KiSS-1. KiSS-1 protein was shown to form a complex with pro-MMP. KiSS-1 protein is known to be processed to peptide ligand of a G-protein-coupled receptor (hOT7T175) named metastin, and suppresses metastasis of tumors expressing the receptor. Active MMP-2, MMP-9, MT1-MMP, MT3-MMP and MT5-MMP cleaved the Gly118-Leu119 peptide bond of not only full-length KiSS-1 protein but also metastin decapeptide. Metastin decapeptide induced formation of focal adhesion and actin stress fibers in cells expressing the receptor, and digestion of metastin decapeptide by MMP abolished its ligand activity. Migration of HT1080 cells expressing hOT7T175 that harbor a high-level MMP activity was only slightly suppressed by either metastin decapeptide or MMP inhibitor BB-94 alone, but the combination of metastin decapeptide and BB-94 showed a synergistic effect in blocking cell migration. We propose that metastin could be used as an antimetastatic agent in combination with MMP inhibitor, or MMP-resistant forms of metastin could be developed and may also be efficacious.

  PMID: 12879005 [PubMed - indexed for MEDLINE]

  
  
  
• Expression profiling of osteosarcoma cells transfected with MDR1 and NEO genes: regulation of cell adhesion, apoptosis, and tumor suppression-related genes.
  

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  Expression profiling of osteosarcoma cells transfected with MDR1 and NEO genes: regulation of cell adhesion, apoptosis, and tumor suppression-related genes.

  Lab Invest. 2003 Apr;83(4):507-17

  Authors: Sanchez-Carbayo M, Belbin TJ, Scotlandi K, Prystowsky M, Baldini N, Childs G, Cordon-Cardo C

  The expression patterns of the osteosarcoma cell line U-2 OS, and three derived subclones containing stably transfected MDR1, NEO and MDR1/NEO genes were compared using cDNA microarrays comprising 8976 known genes and expressed sequenced tags. Data provided new insights into three critical issues. First, MDR1 overexpression was associated with altered expression of genes related to several cellular pathways, including (a). drug influx/efflux (eg, dynamin 3), (b). metabolic enzymes (eg, monoamine oxidase A), (c). cell adhesion (eg, EPCAM), (d). apoptotic signaling (eg, I-TRAF), (e). senescence (eg, telomerase RNA binding protein staufen), (f). tumor suppression-related genes (eg, KISS-1 and ephrin B3), and (g). immune system receptors (eg, LENG2). MDR1, EPCAM, and ephrin B3 expression was confirmed by immunohistochemistry. Second, MDR1 transfected cells selected with either doxorubicin or neomycin showed distinct expression profiles that could be related to differential selection. Moreover, hierarchical clustering indicated that cells transfected with MDR1 alone, or cotransfected with NEO, displayed more closely related expression profiles than cells transfected only with NEO. Third, transfection with NEO and selection with neomycin produced a considerable number of expression changes within the cell. This study further elucidates the genetic events associated with MDR1 expression and identifies novel targets associated with multidrug resistance.

  PMID: 12695554 [PubMed - indexed for MEDLINE]

  
  
  
• KISS1 metastasis suppression and emergent pathways.
  

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  KISS1 metastasis suppression and emergent pathways.

  Clin Exp Metastasis. 2003;20(1):11-8

  Authors: Harms JF, Welch DR, Miele ME

  Metastatic disease is the most critical impediment to cancer patient survival. However, comparatively little is known concerning the intricate pathways which govern the complex phenotypes associated with metastasis. The KISS1 metastasis suppressor gene inhibits metastasis in both in vivo melanoma and breast carcinoma models. Despite its clear physiological activity, the mechanism of KISS1 remains unclear. Recent identification of a 54 amino acid peptide of KISS1, termed metastin or kisspeptin-54, and its cognate G-protein coupled receptor (hOT7T175, AXOR12, GPR54) have provided additional clues and avenues of research. While studies have attributed KISS1 with modulation of NFkappaB regulation, experiments with metastin and its receptor implicate MAP kinase pathways and also suggest the potential of autocrine, paracrine and endocrine roles. Impacts on motility, chemotaxis, adhesion and invasion have each been documented in disparate cell lines and conflicting observations require resolution. Nevertheless, mounting clinical evidence, particularly the loss of KISS1 in metastases, correlates KISS1 and metastin receptor expression with human tumor progression. Together, the data substantiate roles for these molecules in metastasis regulation.

  PMID: 12650602 [PubMed - indexed for MEDLINE]

  
  
  
• Dramatic elevation of plasma metastin concentrations in human pregnancy: metastin as a novel placenta-derived hormone in humans.
  

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  Dramatic elevation of plasma metastin concentrations in human pregnancy: metastin as a novel placenta-derived hormone in humans.

  J Clin Endocrinol Metab. 2003 Feb;88(2):914-9

  Authors: Horikoshi Y, Matsumoto H, Takatsu Y, Ohtaki T, Kitada C, Usuki S, Fujino M

  Metastin is a novel peptide that was recently isolated from human placenta as the endogenous ligand of an orphan heptahelical receptor, hOT7T175. Metastin has been shown to suppress the motility of hOT7T175-transfected melanoma cells; however, studies of the physiological function of metastin have begun only recently. To investigate the possibility that metastin is an endocrine peptide, we determined the immunoreactive (ir-) metastin concentration in human plasma using our newly developed, sensitive, and specific two-site enzyme immunoassay. The plasma concentrations of ir-metastin in males and females were 1.30 +/- 0.14 (n = 12) and 1.31 +/- 0.37 fmol/ml (n = 10), respectively. As metastin is known to be abundant in human placenta, the ir-metastin concentration in the maternal plasma was then determined. The ir-metastin concentrations were 1230 +/- 346 fmol/ml (n = 11) in the first trimester, 4590 +/- 555 (n = 16) in the second trimester, and 9590 +/- 1640 (n = 12) in the third trimester. On d 5 after delivery, the ir-metastin concentration returned to nearly the nonpregnant level (7.63 +/- 1.33 fmol/ml; n = 10), suggesting that ir-metastin increases in pregnancy and is derived mainly from the placenta. The plasma from both nonpregnant and pregnant women showed a single ir-metastin peak at the same retention time as authentic metastin on reverse phase HPLC analysis, indicating that the major portion of the circulating metastin, as determined by our two-site enzyme immunoassay, represents endogenous metastin. Histochemical studies of human placenta localized metastin mRNA and immunoreactivity to the syncytiotrophoblasts. The present study provides evidence for metastin as a novel placenta-derived hormone in humans.

  PMID: 12574233 [PubMed - indexed for MEDLINE]

  
  
  
• Tumor suppressor role of KiSS-1 in bladder cancer: loss of KiSS-1 expression is associated with bladder cancer progression and clinical outcome.
  

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  Tumor suppressor role of KiSS-1 in bladder cancer: loss of KiSS-1 expression is associated with bladder cancer progression and clinical outcome.

  Am J Pathol. 2003 Feb;162(2):609-17

  Authors: Sanchez-Carbayo M, Capodieci P, Cordon-Cardo C

  The expression profiles of nine bladder cancer cell lines were compared against a pool containing equal total RNA quantities of each of them. Lower expression of KiSS-1 was revealed in cells derived from the most advanced bladder tumors. When comparing 15 primary bladder tumors versus a pool of four bladder cancer cell lines, lower transcript levels of KiSS-1 were observed in the invasive bladder carcinomas as compared to superficial tumors. KiSS-1 expression ratios provided prognostic information. The expression pattern of KiSS-1 transcripts was analyzed using in situ hybridization in nine bladder cancer cells, paired normal urothelium and bladder tumor samples (n = 25), and tissue microarrays of bladder tumors (n = 173). We observed complete loss of KiSS-1 in all invasive tumors under study as compared to their respective normal urothelium. The expression of KiSS-1 was found to be significantly associated with histopathological stage. Patients with lower KiSS-1 expression showed a direct correlation with overall survival in a subset of bladder tumors whose follow-up was available (n = 69). We did not observe any significant differential KiSS-1 expression along cell cycle by sorting analysis. A potential tumor suppressor role in bladder cancer was revealed for KiSS-1. Moreover, it showed predictive value by identifying patients with poor outcome.

  PMID: 12547718 [PubMed - indexed for MEDLINE]

  
  
  
• Metastin-like immunoreactivity in the rat medulla oblongata and spinal cord.
  

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  Metastin-like immunoreactivity in the rat medulla oblongata and spinal cord.

  Neurosci Lett. 2003 Jan 2;335(3):197-201

  Authors: Dun SL, Brailoiu GC, Parsons A, Yang J, Zeng Q, Chen X, Chang JK, Dun NJ

  Metastin, the product of metastasis suppressor gene KiSS-1, is proposed to be the natural ligand for the G-protein-coupled receptor GPR54, known also as AXOR12. This immunohistochemical study, using a rabbit polyclonal antiserum against the human metastin fragment (45-54)-NH(2), showed that in rats metastin-like immunoreactivity (MTS-LI) was present in neurons of the nucleus of the solitary tract and caudoventrolateral reticular nucleus, and in cell processes of the spinal trigeminal tract and lateral reticular nucleus. MTS-LI was confined mainly to neurons and fibers at or caudal to the area postrema. In the spinal cord, MTS-LI cell processes formed a dense plexus in superficial layers I and II of the dorsal horn. The pattern of distribution of MTS-LI in the medulla and spinal cord suggests that this novel peptide may participate in autonomic and sensory neural signaling.

  PMID: 12531466 [PubMed - indexed for MEDLINE]

  
  
  
• Transcriptional expression of genes involved in cell invasion and migration by normal and tumoral trophoblast cells.
  

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  Transcriptional expression of genes involved in cell invasion and migration by normal and tumoral trophoblast cells.

  J Clin Endocrinol Metab. 2002 Nov;87(11):5336-9

  Authors: Janneau JL, Maldonado-Estrada J, Tachdjian G, Miran I, Motté N, Saulnier P, Sabourin JC, Coté JF, Simon B, Frydman R, Chaouat G, Bellet D

  Once initiated, invasion of trophoblast cells must be tightly regulated, particularly in early pregnancy. The mechanisms necessary for the invasion and migration of trophoblast cells are thought to be related to those involved in the invasive and metastatic properties of cancer cells. Quantitative PCR was used to measure, in trophoblast cells, the transcriptional expression profiles of four genes, INSL4, BRMS1, KiSS-1 and KiSS-1R, reported to be implicated in tumor invasion and metastasis. Laser capture microdissection and purification of trophoblast cells demonstrate that, as already known for INSL4, BRMS1, KiSS-1 and KiSS-1R are expressed by the trophoblast subset of placental tissues. Expression profiles of these genes studied in early placentas (7-9 weeks, n=55) and term placentas (n=11) showed that expression levels of BRMS1 are higher in term than in early placentas, while expression levels of KiSS-1R are higher in early than in term placentas. Low levels of expression of BRMS1 were observed in normal pregnancies, in molar pregnancies and in choriocarcinoma cell lines BeWo, JAR and JEG3 while, in striking contrast, the expression levels of INSL4, KiSS-1 and Kiss-1R were increased in both early placentas and molar pregnancies and were reduced in choriocarcinoma cells. These transcriptional expression profiles are in favor of a predominant role of INSL4, KiSS-1 and KiSS-1R in the control of the invasive and migratory properties of trophoblast cells.

  PMID: 12414911 [PubMed - indexed for MEDLINE]

  
  
  
• Metastin receptor is overexpressed in papillary thyroid cancer and activates MAP kinase in thyroid cancer cells.
  

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  Metastin receptor is overexpressed in papillary thyroid cancer and activates MAP kinase in thyroid cancer cells.

  J Clin Endocrinol Metab. 2002 May;87(5):2399

  Authors: Ringel MD, Hardy E, Bernet VJ, Burch HB, Schuppert F, Burman KD, Saji M

  The development of distant metastasis is the most important predictor of death from thyroid cancer. KiSS-1 is a recently cloned human metastasis suppressor gene whose product, metastin, was recently identified as the endogenous agonist for a novel Gq/11 coupled receptor (metastin receptor). The expression and functional consequences of metastin and the metastin receptor have not been evaluated in thyroid cancer. We measured metastin and metastin receptor mRNA levels in 10 FCs and 13 papillary carcinomas (PCs), 2 benign non-functioning follicular adenomas (FAs), and 11 normal thyroid samples, and evaluated the signaling pathways activated by metastin in ARO thyroid cancer cells that express the metastin receptor endogenously. Paired normal and tumor samples were available for 4 PC and 3 PFC samples. Metastin mRNA was detected in 6/11 normal samples, and 0/2 FA, 2/10 FC, and 9/13 PC samples (p < 0.05 for PC vs. FC). Metastin receptor was not expressed in any normal thyroid or benign FA samples, and was expressed in only a minority (2/10) of FC samples. However, the receptor was expressed in the majority (10/13) of PCs (p = 0.002 for PC vs. normal tissue). Increased levels of metastin receptor were detected in all four PCs compared to adjacent normal tissue. Incubation levels of metastin receptor were detected in all four PCs compared to adjacent normal tissue. Incubation of metastin receptor expressing ARO thyroid cancer cells with metastin resulted in activation of ERK, but not Akt. Taken together, these data suggest a potential role for metastin and/or metastin receptors in modulating the biological behavior of thyroid cancers.

  PMID: 11994395 [PubMed - indexed for MEDLINE]

  
  
  
• Metastin suppresses the motility and growth of CHO cells transfected with its receptor.
  

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  Metastin suppresses the motility and growth of CHO cells transfected with its receptor.

  Biochem Biophys Res Commun. 2001 Sep 7;286(5):958-63

  Authors: Hori A, Honda S, Asada M, Ohtaki T, Oda K, Watanabe T, Shintani Y, Yamada T, Suenaga M, Kitada C, Onda H, Kurokawa T, Nishimura O, Fujino M

  We recently reported having identified of the ligand for an orphan G-protein-coupled receptor, hOT7T175, as the gene product (68-121)-amide of the metastasis suppressor gene KiSS-1. We further showed that the ligand, which we named "metastin," inhibits chemotaxis and invasion of Chinese hamster ovary (CHO) cells transfected with hOT7T175 cDNA (CHO/h175) in vitro, and pulmonary metastasis of hOT7T175-transfected B16-BL6 melanomas in vivo. In the present study, we investigated the activity of metastin in CHO/h175 cells in greater detail. Metastin significantly suppressed motility in a chemotaxis assay and wound healing assay at 10-100 nM order concentrations. Two N-terminally truncated peptides, metastin(40-54) and metastin(45-54) inhibited the migration of CHO/h175 cells as potently as metastin itself. Metastin also inhibited the spreading, monolayer growth and colony formation in agar (0.8%) of CHO/h175 cells at 10-100 nM concentrations. These results indicate that metastin is a potent inhibitor of cell motility, leading to suppression of cell growth and antimetastatic activity, and suggest that low molecular chemical compounds could replace its activity as a novel antimetastatic agent.

  PMID: 11527393 [PubMed - indexed for MEDLINE]

  
  
  
• The metastasis suppressor gene KiSS-1 encodes kisspeptins, the natural ligands of the orphan G protein-coupled receptor GPR54.
  

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  The metastasis suppressor gene KiSS-1 encodes kisspeptins, the natural ligands of the orphan G protein-coupled receptor GPR54.

  J Biol Chem. 2001 Sep 14;276(37):34631-6

  Authors: Kotani M, Detheux M, Vandenbogaerde A, Communi D, Vanderwinden JM, Le Poul E, Brézillon S, Tyldesley R, Suarez-Huerta N, Vandeput F, Blanpain C, Schiffmann SN, Vassart G, Parmentier M

  Natural peptides displaying agonist activity on the orphan G protein-coupled receptor GPR54 were isolated from human placenta. These 54-, 14,- and 13-amino acid peptides, with a common RF-amide C terminus, derive from the product of KiSS-1, a metastasis suppressor gene for melanoma cells, and were therefore designated kisspeptins. They bound with low nanomolar affinities to rat and human GPR54 expressed in Chinese hamster ovary K1 cells and stimulated PIP(2) hydrolysis, Ca(2+) mobilization, arachidonic acid release, ERK1/2 and p38 MAP kinase phosphorylation, and stress fiber formation but inhibited cell proliferation. Human GPR54 was highly expressed in placenta, pituitary, pancreas, and spinal cord, suggesting a role in the regulation of endocrine function. Stimulation of oxytocin secretion after kisspeptin administration to rats confirmed this hypothesis.

  PMID: 11457843 [PubMed - indexed for MEDLINE]

  
  
  
• AXOR12, a novel human G protein-coupled receptor, activated by the peptide KiSS-1.
  

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  AXOR12, a novel human G protein-coupled receptor, activated by the peptide KiSS-1.

  J Biol Chem. 2001 Aug 3;276(31):28969-75

  Authors: Muir AI, Chamberlain L, Elshourbagy NA, Michalovich D, Moore DJ, Calamari A, Szekeres PG, Sarau HM, Chambers JK, Murdock P, Steplewski K, Shabon U, Miller JE, Middleton SE, Darker JG, Larminie CG, Wilson S, Bergsma DJ, Emson P, Faull R, Philpott KL, Harrison DC

  A novel human G protein-coupled receptor named AXOR12, exhibiting 81% homology to the rat orphan receptor GPR54, was cloned from a human brain cDNA library. Heterologous expression of AXOR12 in mammalian cells permitted the identification of three surrogate agonist peptides, all with a common C-terminal amidated motif. High potency agonism, indicative of a cognate ligand, was evident from peptides derived from the gene KiSS-1, the expression of which prevents metastasis in melanoma cells. Quantitative reverse transcriptase-polymerase chain reaction was used to study the expression of AXOR12 and KiSS-1 in a variety of tissues. The highest levels of expression of AXOR12 mRNA were observed in brain, pituitary gland, and placenta. The highest levels of KiSS-1 gene expression were observed in placenta and brain. A polyclonal antibody raised to the C terminus of AXOR12 was generated and used to show localization of the receptor to neurons in the cerebellum, cerebral cortex, and brainstem. The biological significance of these expression patterns and the nature of the putative cognate ligand for AXOR12 are discussed.

  PMID: 11387329 [PubMed - indexed for MEDLINE]

  
  
  
• Metastasis suppressor gene KiSS-1 encodes peptide ligand of a G-protein-coupled receptor.
  

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  Metastasis suppressor gene KiSS-1 encodes peptide ligand of a G-protein-coupled receptor.

  Nature. 2001 May 31;411(6837):613-7

  Authors: Ohtaki T, Shintani Y, Honda S, Matsumoto H, Hori A, Kanehashi K, Terao Y, Kumano S, Takatsu Y, Masuda Y, Ishibashi Y, Watanabe T, Asada M, Yamada T, Suenaga M, Kitada C, Usuki S, Kurokawa T, Onda H, Nishimura O, Fujino M

  Metastasis is a major cause of death in cancer patients and involves a multistep process including detachment of cancer cells from a primary cancer, invasion of surrounding tissue, spread through circulation, re-invasion and proliferation in distant organs. KiSS-1 is a human metastasis suppressor gene, that suppresses metastases of human melanomas and breast carcinomas without affecting tumorigenicity. However, its gene product and functional mechanisms have not been elucidated. Here we show that KiSS-1 (refs 1, 4) encodes a carboxy-terminally amidated peptide with 54 amino-acid residues, which we have isolated from human placenta as the endogenous ligand of an orphan G-protein-coupled receptor (hOT7T175) and have named 'metastin'. Metastin inhibits chemotaxis and invasion of hOT7T175-transfected CHO cells in vitro and attenuates pulmonary metastasis of hOT7T175-transfected B16-BL6 melanomas in vivo. The results suggest possible mechanisms of action for KiSS-1 and a potential new therapeutic approach.

  PMID: 11385580 [PubMed - indexed for MEDLINE]

  
  
  
• KiSS-1 represses 92-kDa type IV collagenase expression by down-regulating NF-kappa B binding to the promoter as a consequence of Ikappa Balpha -induced block of p65/p50 nuclear translocation.
  

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  KiSS-1 represses 92-kDa type IV collagenase expression by down-regulating NF-kappa B binding to the promoter as a consequence of Ikappa Balpha -induced block of p65/p50 nuclear translocation.

  J Biol Chem. 2001 Jan 12;276(2):1164-72

  Authors: Yan C, Wang H, Boyd DD

  The 92-kDa type IV collagenase (MMP-9) plays a critical role in tissue remodeling. We undertook a study to determine whether the KiSS-1 gene, previously shown to suppress cancer spread (metastases), negatively regulates MMP-9 expression. Six cell lines positive for MMP-9 mRNA were deficient in KiSS-1 mRNA. One of these cell lines, HT-1080, stably transfected with a KiSS-1 expression construct, demonstrated substantially lower MMP-9 enzyme activity/protein and in vitro invasiveness. The lower MMP-9 enzyme activity reflected reduced steady-state mRNA levels which, in turn, was due to attenuated transcription. Activation of ERKs and JNKs by phorbol 12-myristate 13-acetate and tumor necrosis factor alpha, respectively, leading to increased MMP-9 amounts was not antagonized by KiSS-1 expression, suggesting that MAPK pathways modulating MMP-9 synthesis are not the target of KiSS-1. Although MMP-9 expression is regulated by AP-1, Sp1, and Ets transcription factors, KiSS-1 did not alter the binding of these factors to the MMP-9 promoter. However, NF-kappaB binding to the MMP-9 promoter required for expression of this collagenase was reduced by KiSS-1 expression. Diminished NF-kappaB binding reflected less p50/p65 in the nucleus secondary to increased IkappaBalpha levels in the cytosols of the KiSS-1 transfectants. Thus, KiSS-1 diminishes MMP-9 expression by effecting reduced NF-kappaB binding to the promoter.

  PMID: 11060311 [PubMed - indexed for MEDLINE]

  
  
  
• Chromosome localization and genomic structure of the KiSS-1 metastasis suppressor gene (KISS1).
  

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  Chromosome localization and genomic structure of the KiSS-1 metastasis suppressor gene (KISS1).

  Genomics. 1998 Nov 15;54(1):145-8

  Authors: West A, Vojta PJ, Welch DR, Weissman BE

  The identification and sequence of KiSS-1 (HGMW-approved symbol, KISS1), a human malignant melanoma metastasis-suppressor gene, was recently published. In this report, we present a corrected genomic sequence, genomic structure, and refined chromosomal location for KiSS-1. The genomic organization of the sequence reveals a gene consisting of four exons. The first two exons are not translated; the third exon contains 38 5' noncoding bases followed by the translational start site and another 100 translated bases. The terminal exon contains a further 332 translated bases, the translational stop codon, and the polyadenylation signal. The gene maps to chromosome 1q32 as determined by radiation hybrid mapping and FISH analysis. The relatively simple organization of this gene will facilitate analyses for mutations and abnormal expression in human tumors.

  PMID: 9806840 [PubMed - indexed for MEDLINE]

  
  
  
• Suppression of metastasis in human breast carcinoma MDA-MB-435 cells after transfection with the metastasis suppressor gene, KiSS-1.
  

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  Suppression of metastasis in human breast carcinoma MDA-MB-435 cells after transfection with the metastasis suppressor gene, KiSS-1.

  Cancer Res. 1997 Jun 15;57(12):2384-7

  Authors: Lee JH, Welch DR

  Based on the observation that chromosome 1q deletions are not infrequent in late-stage human breast carcinomas, we tested whether the recently discovered human melanoma metastasis suppressor gene, KiSS-1, which maps to chromosome 1q32-q41, could suppress metastasis of the human breast carcinoma cell line MDA-MB-435. Parental, vector-only transfectants and KiSS-1 transfectant clones were injected into the mammary fat pads of athymic nude mice and assessed for tumor growth and spontaneous metastasis to regional lymph nodes and lungs. Expression of KiSS-1 reduced metastatic potential by 95% compared to control cells but did not suppress tumorigenicity. Metastasis suppression correlated with a decreased clonogenicity in soft (0.3%) and hard (0.9%) agar. Although the overall rate of cell adhesion to extracellular matrix components was unaffected, KiSS-1 transfectants spread on immobilized type-IV collagen more rapidly than did control populations. Invasion and motility were unaffected by KiSS-1. Based on the predicted structure of the KiSS-1 protein, our results imply a mechanism whereby KiSS-1 regulates events downstream of cell-matrix adhesion, perhaps involving cytoskeletal reorganization. In addition to its already described role in melanoma, our results show that KiSS-1 also functions as a metastasis suppressor gene in at least some human breast cancers.

  PMID: 9192814 [PubMed - indexed for MEDLINE]

  
  
  
• Identification of highly expressed genes in metastasis-suppressed chromosome 6/human malignant melanoma hybrid cells using subtractive hybridization and differential display.
  

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  Identification of highly expressed genes in metastasis-suppressed chromosome 6/human malignant melanoma hybrid cells using subtractive hybridization and differential display.

  Int J Cancer. 1997 Jun 11;71(6):1035-44

  Authors: Lee JH, Welch DR

  Microcell-mediated transfer of chromosome 6 into human melanoma cell lines C8161 and MelJuSo suppresses metastasis by at least 95% without affecting tumorigenicity. Subtractive hybridization and differential display were used to identify the molecule(s) responsible for suppressing metastasis in neo6/melanoma (neo6/C8161 and neo6/MelJuSo) hybrids. Seven cDNA clones exhibiting quantitatively or qualitatively higher expression in neo6/melanoma hybrids were obtained. These genes fell into 2 categories: 1) transcription-related genes (AP-2A, HMG-I(Y) and a novel isoform of nucleophosmin B23), which have previously been shown to regulate metastasis-associated genes; and 2) novel genes. One of the novel genes, designated KiSS-1, significantly suppressed metastasis of the human malignant melanoma cell lines MelJuSo and a highly metastatic subclone of C8161, C8161cl.9, following transfection and constitutive expression. Our results illustrate the power of subtractive hybridization and differential display to identify functional metastasis-controlling genes in human melanoma.

  PMID: 9185708 [PubMed - indexed for MEDLINE]

  
  
  
• KiSS-1, a novel human malignant melanoma metastasis-suppressor gene.
  

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  KiSS-1, a novel human malignant melanoma metastasis-suppressor gene.

  J Natl Cancer Inst. 1996 Dec 4;88(23):1731-7

  Authors: Lee JH, Miele ME, Hicks DJ, Phillips KK, Trent JM, Weissman BE, Welch DR

  BACKGROUND: Microcell-mediated transfer of chromosome 6 into human C8161 and MelJuSo melanoma cell suppresses their ability to metastasize by at least 95% without affecting their tumorigenicity. This observation demonstrates that the ability to metastasize is a phenotype distinct from tumor formation and suggests that tumorigenic cells acquire metastatic capability only after accumulating additional genetic defects. These results also imply that mutations of genes on chromosome 6 are among those late genetic changes responsible for metastatic potential. They further suggest that a melanoma metastasis-suppressor gene(s) is encoded on chromosome 6 or is regulated by genes on chromosome 6. PURPOSE: Our objective was to identify the gene(s) responsible for the suppression of metastasis in chromosome 6/melanoma cell hybrids. METHODS: A modified subtractive hybridization technique was used to compare the expression of messenger RNAs (mRNAs), via an analysis of complementary DNAs (cDNAs), in metastatic cells (C8161 or MelJuSo) and nonmetastatic hybrid clones (neo6/C8161 or neo6/MelJuSo). RESULTS: A novel cDNA, designated KiSS-1, was isolated from malignant melanoma cells that had been suppressed for metastatic potential by the introduction of human chromosome 6. Northern blot analyses comparing mRNAs from a panel of human melanoma cells revealed that KiSS-1 mRNA expression occurred only in nonmetastatic melanoma cells. Expression of this mRNA in normal heart, brain, liver, lung, and skeletal muscle was undetectable by northern blot analysis. Weak expression was found in the kidney and pancreas, but the highest expression was observed in the placenta. The KiSS-1 cDNA encodes a predominantly hydrophilic, 164 amino acid protein with a polyproline-rich domain indicative of an SH3 ligand (binds to the homology 3 domain of the oncoprotein Src) and a putative protein kinase C-alpha phosphorylation site. Transfection of a full-length KiSS-1 cDNA into C8161 melanoma cells suppressed metastasis in an expression-dependent manner. CONCLUSIONS: These data strongly suggest that KiSS-1 expression may suppress the metastatic potential of malignant melanoma cells. IMPLICATIONS: KiSS-1 may be a useful marker for distinguishing metastatic melanomas from nonmetastatic melanomas.

  PMID: 8944003 [PubMed - indexed for MEDLINE]