OBJECTIVETo investigate the impact of expression of kisspeptin-1 (KiSS-1) metastasis-suppressor gene on the proliferative, adhesive and invasive abilities of human hepatocellular carcinoma (HCC) using an in vitro cell system.

METHODSThe highly metastatic human hepatoma cell line MHCC97-H was transiently transfected with the pcDNA3.1/HisC vector expressing the KiSS-1 gene (experimental group) or the vector without the KisS-1 gene (blank control group). Untransfected cells served as the negative control group. Proliferative abilities of the three groups were assessed by flow cytometry and MTT assay. Adhesive abilities were assessed by MTT assays using matrigel and fibronectin. Invasive abilities and cell motility were assessed by chemoinvasion chamber assay using reconstituted matrigel and migration chamber assay using polycarbonate filters, respectively.

RESULTSThe experimental group showed significantly lower adhesion capacity to matrigel (0.257+/-0.029) than either the blank control group (0.374+/-0.016; t=-7.90345, P less than 0.01) or the negative control group (0.394+/-0.031; t=-7.22752, P less than 0.01). Similarly, the experimental group showed significantly lower adhesion capacity to fibronectin (0.292+/-0.004) than either the blank control group (0.394+/-0.010; t=-20.93138, P less than 0.01) or the negative control group (0.412+/-0.023; t=-11.31371, P less than 0.01). The experimental group also showed significantly lower numbers of cells with invasive capacity (42.40+/-1.14) than either the blank control group (66+/-1.58; t=-27.0711, P less than 0.01) or the negative control group (67.80 +/- 1.92; t=-25.4, P less than 0.01). Similarly, the experimental group showed significantly lower numbers of cells with chemotactic movement (65.80+/-1.92) than either the blank control group (93.80+/-2.28; t=-30.11750, P less than 0.01) or the negative control group (96.40+/-2.07; t=-24.19142, P less than 0.01). The experimental group showed slightly, but not significantly, lower cell proliferation (0.644+/-0.027) than either the blank control group (0.669+/-0.022; t=-1.60371, P?>?0.05) or the negative control group (0.678+/-0.027; t=-1.97828, P?>?0.05). In addition, there were no obvious differences between the three groups in the amounts of cells arrested in either the G1 phase or the S phase.

CONCLUSIONKiSS-1 overexpression suppresses the adhesion, invasion and motility, but not the proliferation, of hepatoma carcinoma cells in vitro. These findings imply that KiSS-1 might represent a promising new candidate for gene therapy against human hepatocellular carcinoma.