MicroRNA-20b在卵巢癌细胞中的表达及对增殖和凋亡的影响

探讨microRNA-20b（miR-20b）在卵巢癌细胞系中的表达及对增殖和凋亡的影响。方法实时荧光定量聚合酶链反应（qRT-PCR）测定miR-20b 在卵巢癌细胞系A431、SKOV3 及正常卵巢上皮细胞系Hose 中的相对表达量，将SKOV3 细胞系分成未转染对照、阴性对照及miR-20b 模拟物组，用Lipofectamine2000 分别不转染、转染miR-20b scramble 和miR-20b mimics，CCK8 实验测定3 组细胞增殖能力，流式细胞术测定3 组细胞凋亡，Western blot测定张力蛋白同源在10 号染色体有缺失的磷酸酶（PTEN）、裂解型聚腺苷二磷酸核糖聚合酶（PARP）的相对表达量。结果qRT-PCR示A431、SKOV3细胞系miR-20b 相对表达量较Hose 细胞系低；miR-20b 模拟物组在0、24、48、72 及96 h的OD45 nm 值低于未转染对照组和阴性对照组；miR-20b 模拟物组凋亡率高于阴性对照组和未转染对照组；miR-20b 模拟物组PTEN 相对表达量低于阴性对照组，裂解型PARP蛋白相对表达量高于阴性对照组。结论miR-20b 抑制卵巢癌细胞增殖并促进凋亡，其机制可能与下调PTEN 和上调PARP 蛋白表达有关。

Expression of miR-20b in ovarian carcinoma cell line and its effect on proliferation and apoptosis

To investigate the expression of miR-20b in ovarian carcinoma cell line and its effect on proliferation and apoptosis. Methods The relative expression levels of miR-20b in A431, SKOV3 and Hose celllines were measured by qRT-PCR. The SKOV3 cell line was divided into non-transfection control group without transfection, negative control group transfected with miR-20b scramble and miR-20b mimics group transfected with miR-20b mimics by Lipofectamine 2000. The proliferation ability was tested by CCK8 assay. The apoptosis rate was measured by flow cytometry. The expression levels of phosphatase and tensin homolog deleted from chromosome 10(PTEN) and cleaved poly(ADP-ribose) polymerase (PARP) were measured by Western blot. Results The expression levels of miR-20b in the A431 and SKOV3 cell lines were significantly lower than that in the Hose cell line. The value of OD 450 nm in the miR-20b mimics group was significantly lower than that in the non-transfection control and negative control groups at 0, 24, 48, 72 and 96 h. The apoptosis rate of the miR-20b mimics group was signifi-cantly higher than that of the negative control and non-transfection control groups. Compared to the negative control group, the expression level of PTEN was down-regulated and the cleaved PARP was up-regulated in the miR-20b mimics group. Conclusions miR-20b inhibits proliferation and promotes apoptosis of ovarian carcinoma cells, the mechanism may be associated with down-regulation of PTEN and up-regulaton of cleaved PARP.