转染miR-200b类似物的宫颈癌细胞对紫杉醇敏感度的变化及其机制

The sensitivity change and its mechanism of cervical cancer cells transfected with miR-200b analogues to paclitaxel

目的观察转染miR-200b模拟物的宫颈癌HeLa细胞对紫杉醇的敏感度变化，并探讨其机制。方法培养宫颈癌HeLa细胞，将HeLa细胞分为观察组、对照组、单药组，三组均经0、25、50、100、200ng／ml紫杉醇处理，观察组转染miR-200b模拟物，对照组转染无关序列，单药组不转染任何序列，MTF法观察各组HeLa细胞增殖能力，AnnexinV—FITC／PI法检测各组HeLa细胞凋亡率。将宫颈癌HeLa细胞分为实验组1、实验组2、实验组3，三组均采用25ng／ml紫杉醇处理，实验组1转染miR-200b模拟物，实验组2转染无关序列，实验组3不转染任何序列，采用Westernblot法检测HeLa细胞中VEGF蛋白。结果MTF实验结果显示，观察组内不同浓度紫杉醇处理HeLa细胞的OD值与对照组和单药组比较均明显下降（P〈0．05），对照组与单药组比较差异无统计学意义（P〉0．05）；AnnexinV—FITC／PI法结果显示，观察组内不同浓度紫杉醇处理HeLa细胞的凋亡率与对照组和单药组比较均明显增加（P〈0．05），对照组与单药组比较差异无统计学意义（P〉0．05）；Westernblot结果显示，实验组1、实验组2、实验组3宫颈癌HeLa细胞中VEGF蛋白相对表达量分别为0．403±0．046、0．882±0．094、0．901±0．102，实验组1与实验组2、3比较差异均有统计学意义（P〈0．05）。结论转染miR-200b模拟物的宫颈癌HeLa细胞对紫杉醇的敏感度增强，miR-200b可能通过靶向调控VEGF诱导宫颈癌细胞对紫杉醇的敏感度增高。

Objective To explore the effect of miR-200b on chemosensitivity of cervical cancer HeLa cells to paclitaxel and its mechanism. Methods A recombinant miR-200b mimics was transfected in- to cultured HeLa cells, which were divided into observation group, negative group, and blank control group. Each group was treated with different concentrations of pacfitaxel. Methyl thiazolyl tetrazolium （MTT） assay was performed to evalate the proliferative ability of these treated cells to paclitaxel. AnnexinV- FITC/PI method was used to detect the apoptosis rate of Hela cells. The protein level of vascular endothelial growth factor （VEGF） was detected by Western blot. Results MTY assay showed that the OD values of three groups were totally different; and compared to the other two groups, the OD value of the transfected HeLa cells was significantly lower （ P 〈 0. 05 ）. Compared to the negative group and the blank control group, there was no statistical difference （ P 〉 0. 05 ）. AnnexinV-FITC/PI results demonstrated that the ap- optotic index of the transfected HeLa cells was significantly higher than that in the other two groups （ P 〈 0.05 ）. Western blot assay showed that expression of VEGF protein in three groups of relative quantity was 0.403±0. 046, 0.882 ＋ 0.094, and 0. 901 0. 102, respectively. There was significant difference among there groups （ P 〈 0. 05 ）. Conclusions miR-200b mimics can increase the sensitivity of cervical cancer HeLa cells to pacfitaxel, and targeted regulation of VEGF may be the cause of increasing in drug sensitivity.