E167K polymorphism of TM6SF2 gene affects cell cycle of hepatocellular carcinoma cell HEPA 1-6

Background: Some studties reported that the polymorphism of TM6SF2 gene E167K affects the occurrence and the progression of hepatocytes carcinoma (hepatocellular, HCC). In oeder to investigate the effects of the polymorphism of TM6SF2 gene E167K in the pathogenesis of HCC, we explored its influence on the cell cycle in hepatocellular carcinoma cell HEPA1-6. Methods: HEPA 1-6 cells which could respectively overexpress TM6SF2 wild type and E167K variant were cultured and HEPA 1-6 cells with zero load plasmids were used as matched control. Flow cytometry was used to detect the cell cycles of these 3 type of HEPA 1-6 cells. Realtime fluores-cence quantitative PCR and western blot were used to analyzed the expression of regulatory factors (Cyclin D1p53P16P27P21 and Rb) of cell cycle. T-test was used in statistical analysis. Results: Cell cycle phase distribution was presented by the proportion of cells in each phases (%). Compared with the control group, the cell cycle phase distribution (G₁ phase 57.36 ± 0.21%, G₂/M phase 25.61 ± 0.36%,S phases 19.31 ± 0.25%) had no differences in wild type group (G₁ phase 57.63 ± 0.28%, G₂/M phase 25.77 ± 0.51%, S phases 19.54 ± 0.25%; P < 0.05). Between variant type group and wild type group,G₁ phase was significantly decreased (variant type group G₁ phase 36.26 ± 0.31%, P < 0.05),S phase and G₂/M phase were increased(variant type group S phase 28.41 ± 0.31%, P < 0.05;G₂/M phase 35.23 ± 0.14%, P < 0.05), respectively. Compared with control group,the relative expression of CyclinD1P53 and Rb mRNA in variant type group was significantly upregulated (2.03 ± 0.01 VS 1.04 ± 0.06, 1.88 ± 0.05 VS 1.37 ± 0.03, 1.29 ± 0.06 VS 1.15 ± 0.03, P < 0.05) and P27 mRNA in variant type group was significantly downregulated (0.56 ± 0.02 VS 0.85 ± 0.05, P < 0.05). Compared with wild type group, the relative expression of CyclinD1P53 and Rb mRNA in variant type group was significantly upregulated (wild type group 1.00 ± 0.00, 1.48 ± 0.09, 1.18 ± 0.01, P < 0.05) and P27 mRNA in variant type group was significantly downregulated (variant type group 0.82 ± 0.05,P < 0.05). There was no statistical significance between wild type group and control group (P > 0.05). P16 and P21 expression showed no statistical sigtfificance in any of these three groups (P > 0.05). Conclusion: E167K polymorphism of TM6SF2 gene affects cell cycles of HEPA1-6 cells via up-regulating CyclinD1P53 and Rb and down-regulating P27.