A twisted kiss: in vitro and in vivo evidence of genetic variation and suppressed transcription of the metastasis-suppressor gene KiSS1 in early breast cancer

KISS1 in metastatic cancer research and treatment: potential and paradoxes

The significance of KISS1 goes beyond its original discovery as a metastasis suppressor. Its function as a neuropeptide involved in diverse physiologic processes is more well studied. Enthusiasm regarding KISS1 has cumulated in clinical trials in multiple fields related to reproduction and metabolism. But its cancer therapeutic space is unsettled. This review focuses on collating data from cancer and non-cancer fields in order to understand shared and disparate signaling that might inform clinical development in the cancer therapeutic and biomarker space. Research has focused on amino acid residues 68-121 (kisspeptin 54), binding to the KISS1 receptor and cellular responses. Evidence and counterevidence regarding this canonical pathway require closer look at the covariates so that the incredible potential of KISS1 can be realized.

Q36R polymorphism of KiSS-1 gene in Brazilian head and neck cancer patients

The KiSS-1 metastasis-suppressor gene (KiSS-1) product (metastin, kisspeptin) is reported to act after binding with the natural ligand of a G-protein coupled receptor and this gene product inhibits chemotaxis, invasion, and metastasis of cells. The aim of this study was to evaluate the Q36R polymorphism of KiSS-1 in patients with head and neck cancer and to compare the results with healthy individuals and its association with clinicopathological parameters. Gender, age, smoking and alcohol consumption were analyzed for 744 individual (252 head and neck cancer patients and in 522 control individuals). The molecular analysis of these individuals was made after extraction of genomic DNA using the SSCP-PCR technique. This study did not reveal any significant differences in genotype frequencies between healthy individuals and patients with head and neck cancer or with the clinical parameters. This study showed an increase frequency of the Q36R polymorphism in pharyngeal cancer.

Expression of KiSS-1 in Epithelial Ovarian Cancer and its Role in Metastasis

Objectives To study expression of KiSS-1 and its role in migration and invasion of ovarian cancer (OC). Methods Expression of KiSS-1 was detected in tissue of 46 cases of OC and 17 cases of benign ovarian neoplasm by immunohistochemistry examination. Human OC cell line HO8910 was transfected by pcDNA3-KiSS-1 vector. The cell proliferation and invasion properties were detected by RT-RCR, MTT, clone formation rate and Boyden Chamber invasion assay. Results (1) Immunostaining showed that expression of KiSS-1protein was significantly higher in OC than that in benign ovarian tumor (P<0.05). (2) KiSS-1 expression was significantly higher in cases of advanced stage and with lymphatic metastasis (P<0.05). KiSS-1 expression was significantly lower in clear cell cancer compared with other histologic types (P<0.05). (3)KiSS-1 gene was successfully integrated into the genomic DNA of ovarian cancer cell line HO8910. Boyden Chamber invasion assay revealed that the number of cells invading through the Matrigel filter was significantly decreased in the transfected group compared with the non-transfected. No differences were observed in cell proliferation between the two groups. Conclusion There was over expression of KiSS-1 in OC compared with that in benign ovarian tumor. The KiSS-1 gene could suppress HO8910 invasion in vitro. To elucidate the contradiction effects of metastasis suppressor genes KiSS-1in vivoandin vitroneeds deeper research.

Clinicopathological significance of Kiss-1 expression in esophageal squamous cell carcinoma

AIM: To investigate the expression of Kiss-1 mRNA and protein in esophageal squamous cell carcinoma (ESCC) and to analyze its clinicopathological significance.

METHODS: Sixty-two ESCC specimens, 31 atypical hyperplastic epithelial specimens, and 62 normal esophageal epithelial specimens were used in the study. The expression of Kiss-1 mRNA in these specimens was detected by in situ hybridization and reverse transcription-polymerase chain reaction (RT-PCR). The expression of Kiss-1 was detected by immunohistochemistry using the streptavidin-peroxidase method. The clinicopathological significance of Kiss-1 expression in ESCC was then analyzed.

RESULTS: The positive rates of Kiss-1 protein expression in ESCC, adjacent atypical hyperplastic epithelium and normal esophageal epithelium tissues were 56.5%, 67.7%, 90.3%, respectively (all P < 0.05). The positive rates of Kiss-1 mRNA expression in ESCC, adjacent atypical hyperplastic epithelium and normal esophageal epithelium tissues were 51.6%, 74.2% and 95.2%, respectively, as revealed by in situ hybridization (all P < 0.05), and 54.8%, 71.0% and 88.7%, respectively, by RT-PCR (all P < 0.05). The positive rates of Kiss-1 protein and mRNA expression in ESCC were closely associated with lymph node metastasis (both P < 0.05), but not with sex, age, histological grade and infiltration depth (all P > 0.05). A positive correlation was noted not only between the positive rates revealed by in situ hybridization and RT-PCR (P < 0.05), but also between those revealed by immunohistochemistry and RT-PCR or in situ hybridization (both P < 0.05).

CONCLUSION: The low expression of Kiss-1 is closely associated with the development, progression and metastasis of ESCC. Kiss-1 may be used as an important parameter for early diagnosis and prognosis of ESCC.