The metastasis suppressor KISS1 lacks antimetastatic activity in the C8161.9 xenograft model of melanoma

Kisspeptin and Cancer: Molecular Interaction, Biological Functions, and Future Perspectives

Cancer disease is the second leading cause of death in the world and one of the main fields of medical research. Although there is now a greater understanding of biological mechanisms of uncontrolled cell growth, invasiveness and metastasization, the multi-step process of cancer development and evolution is still incompletely understood. The inhibition of molecules activated in cancer metastasization is an hot topic in cancer research. Among the known antimetastatic genes, KiSS-1 is involved in the metastatic cascade by preventing growth of metastasis. Moreover, loss of KiSS-1 protein expression by tumor cells has been associated with a more aggressive phenotype. KiSS-1 gene encodes a 145-amino acid protein, which following proteolytic cleavage, generates a family of kisspeptins (Kp-10, -13, and -14), that are endogenous agonists for the G-protein-coupled receptor (GPR54). The antitumor effect of KiSS-1 was primarily associated with the inhibition of proliferation, migration and cell invasion and, consequently, the reduced formation of metastasis and intratumoral microvessels. In this review, we highlight the latest data on the role of kisspeptin signaling in the suppression of metastasis in various cancer types and the use modulators of KiSS/GPR54 signaling as potential novel therapeutic agents for the treatment of cancer.

KiSS1 inhibits growth and invasion of osteosarcoma cells through inhibition of the MAPK pathway

As a metastasis suppressor, KiSS1 has been implicated in numerous human cancers. However, recent studies have demonstrated that KiSS1 promotes tumor growth and metastasis in breast cancer, and it is unclear about the expression and function of KiSS1 in human osteosarcoma (OS). The aim of the present study was to investigate the role and molecular mechanisms of KiSS1 in human OS. The expression of KiSS1 was assessed by immunohistochemical assay using a tissue microarray procedure in forty cases of OS tissues. A gain-of-function approach was used to observe the effects of lentiviral vector-mediated overexpression of KiSS1 (Lv-KiSS1) on the biological behaviors including proliferative activities and invasive potential of OS MG-63 cells, indicated by MTT and Transwell assays, respectively. The results showed that the expression of KiSS1 protein in OS tissues was significantly lowered compared to that in adjacent non-cancerous tissues (ANCT) (42.5% vs 70.0%, P=0.023), and had negative correlation with distant metastases of the tumor (P=0.019). Overexpression of KiSS1 inhibited proliferation and invasion of OS cells with the decreased expression of p38 MAPK and matrix metalloproteinase-9 (MMP-9). Taken together, our findings indicate that the decreased expression of KiSS1 is correlated with distant metastasis of OS, and KiSS1 may function as a tumor suppressor in OS cells through inhibition of the MAPK pathway, suggesting that KiSS1 may serve as a potential therapeutic target for the treatment of cancer.