The effect of targeting miRNA interfering with Bmi-1 expression on human gallbladder cancer cell proliferation

WEI Dong; ZOU Hao; WANG Lin; WU Xue-song; LUO Zhi-ling; WANG Tao; ZHANG Xiao-wen

doi:10.3969/j.issn.1006-5725.2014.05.008

Abstract：Objective Via targeted inhibition of oncogene Bmi-1 expression by RNAi interfering technology in vitro, to observe its effect on the proliferation and cell cycle of gallbladder cancer cells. Methods Four miRNABmi-1 recombinant plasmids were constructed according to different Bmi-1 sites. RT-PCR and Western blot were used to mRNA and protein expression of Bmi-1 in gallbladder cancer cells were measured by RT-PCR and Western blot. mRNA and protein expression of Bmi-1 in gallbladder cancer cells. The most effective interfering plasmids in the miRNABmi-1 groups were transfected into GBC-SD cells. Cell proliferation and cell cycle were analyzed 48 h after transfection by BrdU and flow cytometry. Results Bmi-1mRNA expression in miRNAbmi1-1,-3 and-4 was significantly lower than the control group (P<0.05);and Bmi-1 protein expression in miRNAbmi1-2,-3 and-4 was significantly lower than the control group (P<0.05). The recombinant plasmid in miRNAbmi1-4, with the strongest inhibitive effect of Bmi-1mRNA and protein expression, was transfected into GBC-SD cells,then the cell proliferation rate (46.63 ± 5.31) was significantly lower in mRNABmi1-4 group than the control groups (P<0.05);G0/G1 phase cells increased (72.20 ± 1.71) and G2/M and S phase cells decreased (18.30 ± 7.21, 9.50 ± 6.01) in miRNABmi1-4 group. Both were significantly different from the control groups (P<0.05). Conclusions Targeting and silencing Bmi-1 expression can effectively inhibit the proliferation of GBC-SD cells and restrain the cell cycle atin G0/G1 phase. Bmi-1 gene may be a novel target for geneic therapy of gallbladder carcinoma.