miR-200c靶向调控DNMT1诱导卵巢癌细胞对紫杉醇的敏感性

miR-200c induced ovarian cancer cell sensitivity to paclitaxel by targeting DNMT1

目的研究miR-200c调控人类卵巢癌对紫杉醇敏感性的影响及其作用机制。方法培养卵巢癌SKOV3细胞,将SKOV3细胞分为miR-200c模拟物组、无关序列对照组及单药组,三组均分别采用0 ng/mL、25 ng/mL、100 ng/mL、400 ng/mL紫杉醇处理,miR-200c模拟物组转染miR-200c模拟物,无关序列对照组转染无关序列,单药组不转染任何序列,MTT法检测不同浓度紫杉醇及联合miR-200c对卵巢癌细胞增殖能力的影响;Annexin V-FITC/PI法检测不同浓度紫杉醇及联合miR-200c对卵巢癌细胞凋亡能力的影响;Western blot试验检测紫杉醇联合miR-200c模拟物对DNMT1蛋白表达的影响。结果 MTT结果显示,不同浓度紫杉醇处理后三组的卵巢癌细胞的增殖能力随紫杉醇浓度的增加而逐渐下降,miR-200c模拟物组SKOV3细胞的增殖能力与无关序列对照及单药组比较均明显下降,差异均有统计学意义(P<0.05),而无关序列对照与单药组比较差异无统计学意义(P>0.05);Annexin V-FITC/PI法结果显示,不同浓度紫杉醇处理后三组的SKOV3细胞的凋亡率随紫杉醇浓度的增加而逐渐增加,miR-200c模拟物组SKOV3细胞的凋亡率与无关序列对照及单药组比较均明显增加,差异均有统计学意义(P<0.05),而无关序列对照与单药组比较差异无统计学意义(P>0.05);Western blot试验结果显示,miR-200c模拟物与紫杉醇共处理组SKOV3细胞中DNMT1的蛋白表达水平较单独转染miR-200c模拟物组明显降低,差异有统计学意义(P<0.05)。结论 miR-200c可通过调控靶蛋白DNMT1的表达促进卵巢癌细胞对紫杉醇的敏感性。

Objective To study the effect of miR-200 c on the sensitivity of human ovarian cancer to paclitaxel and its mechanism. Methods Ovarian cancer SKOV3 cells were cultured. The SKOV3 cells were divided into miR-200 c mimics group, unrelated sequence control group and single drug group. All three groups were treated with0 ng/mL, 25 ng/mL, 100 ng/mL, 400 ng/mL paclitaxel, respectively. The miR-200 c mimic was transfected into the miR-200 c mimic group, the unrelated sequence negative group was transfected with unrelated sequence, and the single drug group was not transfected with any sequence. The proliferation ability of SKOV3 cells in the different concentrations of paclitaxel and combined miR-200 c were detected by tetrazolium（MTT） assay. The apoptosis rate of SKOV3 cells in different concentrations of paclitaxel and combined miR-200 c were detected by Annexin V-FITC/PI assay. The protein expression of DNMT1 of SKOV3 cells in paclitaxel and combined miR-200 c mimic was detected by Western blot. Results MTT results showed that the proliferation ability of SKOV3 cells decreased gradually with the increase of paclitaxel concentration in different concentrations of paclitaxel-treated groups, and the proliferative capacity of SKOV3 cells in the miR-200 c mimics group was significantly decreased compared with the unrelated sequence control group and single drug group（P〈0.05）, with no significant difference between the unrelated sequence control group and single drug group（P〈0.05）. The Annexin V-FITC/PI method showed that the apoptotic rate of SKOV3 cells gradually increased with the increase of paclitaxel concentration in different concentrations of paclitaxel-treated groups, and the apoptotic rate of SKOV3 cells in the miR-200 c mimics group was significantly increased compared with the unrelated sequence control group and single drug group（P〈0.05）, with no significant difference between the unrelated sequence control group and single drug group（P〈0.05）. Western blot results showed that the expression of DNMT1 protein in the SKOV3 cells cotreated with miR-200 c mimic and paclitaxel was significantly lower than that of miR-200 c mimic alone（P〈0.05）. Conclusion miR-200 c can promote the sensitivity of ovarian cancer cells to paclitaxel by targeting the DNMT1.