MiR-26b增强顺铂对宫颈癌细胞株Hela的杀伤活性研究

摘要

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 cervi-cal 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 Hela cells was regulated by miR-26b. A Mcl-1 expression vector was constructed to detect the role of Mcl-1 vector toward miR-26b plus cisplatin-inducing cytotoxicity in Hela cells by MTT 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 1mol/L cisplatin group showed a higher growth inhibition(52.6%±6.9%) than 1μmol/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.%目的：观察microRNA-26b（miR-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、Si-Ha和C-33a的miR-26b表达水平。MTT法检测顺铂单独治疗及联合miR-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miR-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miR-26b联合顺铂杀伤Hela细胞疗效的影响。结果宫颈癌细胞系miR-26b表达水平：Hela细胞为（0.21±0.04），SiHa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）。miR-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）％]。miR-26b转染后，Hela细胞Mcl-1蛋白表达水平下降。miR-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miR-26b联合1μmol/L顺铂组[细胞活力抑制率为（55.7±7.6）％]。结论 MiR-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。