The study found that forcing liver cancer cells to make more of the protein made by the KiSS1 gene (which includes kisspeptin-10) actually made those cancer cells grow faster, move more, and form new blood vessels, leading to bigger tumors in mice. In plain terms, more KiSS1 seemed to help liver cancer get worse, not better.

Liver cancer has a high prevalence, with majority of the cases presenting as hepatocellular carcinoma (HCC). The prognosis of metastatic HCC has hardly improved over the past decade, highlighting the necessity for liver cancer research. Studies have reported the ability of the <i>KiSS1</i> gene to inhibit the growth or metastasis of liver cancer, but contradictory research results are also emerging. We, therefore, sought to investigate the effects of <i>KiSS1</i> on growth and migration in human HCC cells. HepG2 human HCC cells were infected with lentivirus particles containing <i>KiSS1</i>. The overexpression of <i>KiSS1</i> resulted in an increased proliferation rate of HCC cells. Quantitative polymerase chain reaction and immunoblotting revealed increased Akt activity, and downregulation of the G1/S phase cell cycle inhibitors. A significant increase in tumor spheroid formation with upregulation of &#x3b2;-catenin and CD133 was also observed. <i>KiSS1</i> overexpression promoted the migratory, invasive ability, and metastatic capacity of the hepatocarcinoma cell line, and these effects were associated with changes in the expressions of epithelial mesenchymal transition (EMT)-related genes such as E-cadherin, N-cadherin, and slug. <i>KiSS1</i> overexpression also resulted in dramatically increased tumor growth in the xenograft mouse model, and upregulation of proliferating cell nuclear antigen (PCNA) and Ki-67 in the HCC tumors. Furthermore, <i>KiSS1</i> increased the angiogenic capacity by upregulation of the vascular endothelial growth factor A (VEGF-A) and CD31. Based on these observations, we infer that <i>KiSS1</i> not only induces HCC proliferation, but also increases the metastatic potential by increasing the migratory ability and angiogenic capacity.