Abstract: Objective: To explore the effects of KISS1 gene transfected by lentivirus on the proliferation, invasion and migration abilities of the colorectal cancer HCT116 cells,and to clarify their mechanisms. Methods: The human colorectal cancer cells with the lowest expression level of KISS1 gene were selected. The lentiviral vectors were builted and transfected the KISS1 gene, and the cells were divided into control group (treated with PBS), empty vector group (treated with empty vector) and over-expression group(treated with KISS1 gene vector).The multiplicity of infection (MOI) of the cells was detected by fluorescence microscope.Real-time PCR and Western blotting methods were used to detect the expression levels of KISS1 mRNA and protein(metastin);CCK-8 method was used to detect the proliferation ability of the cells; Transwell chambers method was used to detect the invasion and migration abilities of the cells. Results: Among LoVo, SW620, SW480, HCT-116, and HT29 cells, the expression levels of KISS1 mRNA and protein were lowest in HCT116 cells, so they were chosen as the research carrier. After transfected with lentiviral vectors, the HCT116 cells could stably express the enhanced green fluorescent protein(EGFP) gene, and the MOI was over 80%. Compared with control group and empty vector group, the expression levels of KISS1 mRNA and protein in the cells in over-expression group were significantly increased (P<0.05); the proliferation abilities of the cells in over-expression group were decreased (P<0.05); the invasion ability and migration ability of the cells in over-expression group were decreased (P<0.05). But the differences of proliferation ability,invasion ability and migration ability of the cells between control group and empty vector group were not statistically significant (P>0.05). Conclusion: The KISS1 gene transfected by lentivirus vector can over-express KISS1 protein and inhibit the proliferation, invasion and migration abilities of the colorectal cancer cells, and the mechanism may be related to the expression of KISS1 protein.

Key words: KISS1, colorectal neoplasms, invasion, metastasis, transfection