MiR-26b增强顺铂对宫颈癌细胞株Hela的杀伤活性研究

Mi R-26b Enhances the Cytotoxicity of Cisplatin by Targeting Mcl-1 in Cervical Cancer Cell Line Hela

目的观察micro RNA-26b(mi R-26b)联合顺铂对宫颈癌细胞的杀伤效果,并探讨其作用机制。方法荧光定量PCR方法检测人正常宫颈上皮细胞系CRL-2614及宫颈癌细胞系Hela、SiHa和C-33a的mi R-26b表达水平。MTT法检测顺铂单独治疗及联合mi R-26b治疗对宫颈癌细胞系Hela的杀伤活性。利用生物信息学及Western blot方法验证mi R-26b是否调节Hela细胞Mcl-1表达。构建Mcl-1真核表达载体,MTT法检测Mcl-1表达载体转染对mi R-26b联合顺铂杀伤Hela细胞疗效的影响。结果宫颈癌细胞系mi R-26b表达水平:Hela细胞为(0.21±0.04),Si Ha细胞为(0.42±0.03),C-33a细胞为(0.33±0.03),显著低于正常宫颈上皮细胞系CRL-2614的(1.00±0.05)(P<0.05)。mi R-26b联合1μmol/L顺铂治疗组对Hela细胞的杀伤活性[细胞活力抑制率为(52.6±6.9)%]显著高于1μmol/L顺铂单治疗组[细胞活力抑制率为(6.7±3.5)%]。mi R-26b转染后,Hela细胞Mcl-1蛋白表达水平下降。mi R-26b联合1μmol/L顺铂在Mcl-1表达载体转染后对Hela细胞的杀伤活性[细胞活力抑制率为(19.6±6.7)%]显著低于未转染Mcl-1表达载体的mi R-26b联合1μmol/L顺铂组[细胞活力抑制率为(55.7±7.6)%]。结论 Mi R-26b通过靶向于Mcl-1增强顺铂对宫颈癌细胞系Hela的杀伤活性。

Objective To investigate the effect of microRNA-26b（miR-26b） on cisplatin therapy in treatment of cervical cancer in vitro, and to explore the underlying mechanism. Methods The miR-26b level in normal cervical cell line CRL-2614 and cervical cancer cell lines Hela, SiHa and C-33a were detected by using RT-qPCR. MTT assay was performed to measure the growth inhibition capacity of miR-26b plus cisplatin in Hela cells. Bioinformatics and western blot were performed to determine whether the expression of Mcl-1 in I-Iela cells was regulated by miR-26b. A Mcl-1 expression vector was constrncted to detect the role of Mcl-1 vector toward miR- 26b plus cisplatin-inducing cytotoxicity in Hela cells by MTF assay. Results A down-regulation of miR-26b was found in cervical cancer cell lines Hela（0.21±0.04）, SiHa（0,42±0.03）, and C-33a（0.33±0.03） compared with that in normal cervical cell line CRL-2614 （1.00±0.05）. The miR-26b plus lmol/L cisplatin group showed a higher growth inhibition（52.6%±6.9%） than μmol/L cisplation group （6.7%±3.5%） in Hela cells. The expression of Mcl- 1 at protein level was down-regulated after miR-26b transfection. The growth inhibition of Hela cells treated with miR-26b plus cisplatin was significantly decreased after transfection of Mcl-1 expression vector. Conclusion miR- 26b sensitizes cisplatin-induced cytotoxicity by targeting Mcl-1 in cervical cancer.