miRNA-100下调polo样激酶1表达促进肝癌HepG2细胞凋亡

miRNA-100 promotes hepatic carcinoma HepG2 cell apoptosis through down-regulating polo-like kinase 1 expression

目的:探讨microRNA-100(miR-100)对人肝癌HepG2细胞中polo样激酶1(polo-like kinase 1,Plk1)表达和细胞凋亡的影响。方法:通过oligofectamine介导,将miR-100 mimics转染入HepG2细胞中,RT-PCR和细胞免疫荧光法检测Plk1 mRNA和蛋白的表达,并采用AnnexinⅤ-FITC试剂盒检测HepG2细胞的凋亡情况。结果:miR-100 mimics成功转染HepG2细胞,转染效率为(88.75±2.22)%。转染48 h后,miR-100 mimics组HepG2细胞Plk1 mRNA的表达水平明显低于阴性对照组、空白对照组和脂质体组[(0.71±0.01)vs(0.95±0.01)、(0.92±0.02)、(0.93±0.02),均P<0.01];转染72 h后,miR-100 mimics组Plk1蛋白几乎不表达,同时其细胞凋亡率明显高于阴性对照、空白对照组和脂质体组[(26.95±6.72)%vs(15.03±5.12)%、(6.88±3.71)%、(9.00±3.37)%,均P<0.05]。结论:miR-100能够抑制Plk1基因的表达,从而促进肝癌HepG2细胞的凋亡。

Objective：To explore the effects of microRNA-100（miR-100）on expression of polo-like kinase 1 （Plk1） and the apoptosis of human hepatic carcinoma HepG2 cells. Methods： HepG2 cells were transfected with miR-100 mimics by oligofectamine. RT-PCR and immunofluorescence were used to analyze Plk1 mRNA and protein expressions in HepG2 cells, respectively. Moreover, the apoptosis of HepG2 cells was detected by AnnexinⅤ-FITC kit. Results： HepG2 cells were successfully transfected by miR-100 mimics and the transfection efficiency was （88.75±2.22） %. 48 h after transfection, the expression of Plk1 mRNA decreased significantly in the miR-100 mimics transfection group compared with the negative control, blank control, and liposome groups （／[0.71±0.01／] vs ／[0.95±0.01／], ／[0.92±0.02／], ／[0.93±002／],P〈0.01）. 72 h after transfection, Plk1 protein expression was almost undetectable in HepG2 cells transfected with miR-100 mimics. Meanwhile, the cell apoptosis rate in the miR-100 mimics group was significantly increased in comparison with those in the negative control, blank control, and liposome groups （／[26.95±6.72／]% vs ／[15.03±512／]%, ／[6.88±3.71／]%, ／[9.00±3.37／]%, P〈0.05）. Conclusion： miR-100 can inhibit the expression of Plk1 gene, therefore promoting the apoptosis of hepatic carcinoma HepG2 cells.