microRNA-21参与调控膀胱癌细胞增殖及多柔比星敏感性的研究

目的膀胱移行细胞癌是一种常见的恶性肿瘤,且复发率很高。由于microRNA-21(miR-21)在多种类型肿瘤中参与肿瘤发生及耐药,故通过此次研究探索其在膀胱移行细胞癌中的功能。方法肿瘤组织及癌旁正常组织中的miR-21及目的蛋白PTEN表达水平分别采用实时qRT-PCR及Western blot方法进行测量。采用MTT法评估miR-21对于癌细胞增殖以及多柔比星敏感性的影响。采用流式细胞术探究T24细胞系中多柔比星引起的细胞凋亡。结果与癌旁正常膀胱组织相比,miR-21在膀胱肿瘤组织中的表达水平显著上调,而PTEN蛋白表达低水平。活体内研究发现miR-21与PTEN表达呈负相关。miR-21过表达可显著促进T24细胞系的细胞增殖与多柔比星敏感性。结论 miR-21可能是膀胱移行细胞癌的致癌因素,有望成为膀胱移行细胞癌的治疗新靶点。

microRNA-21 modulates cell proliferation and sensitivity to doxorubicin in bladder cancer cells

Objective Transitional cell carcinomas （TCCs） of the urinary bladder are common malignancies with a high recurrence rate. Since microRNA-21 （miR-21） may contribute to tumorigenesis and chemoresistance in many cancer types, we aimed to investigate its efficacy in TCCs. Methods The expression of miR-21 and its target PTEN was determined by real-time qRT-PCR and western blotting, respectively in tumor tissues as well as adjacent non-tumor mucosa. The effect of miR-21 on cell proliferation and chemosensitivity to doxorubicin were measured using the MTT method. Cell apoptosis induced by doxorubicin was investigated using flow cytometry in the T24 cell line. Results MiR-21 was significantly up-regulated in tumor tissues while PTEN was expressed in lower levels compared to non-tumor tissues. A negative correlation between expression of miR-21 and PTEN was established in vivo. Conclusion Cell proliferation and chemoresistance to doxorubicin were promoted by overexpression of miR-21 in T24 cells.