miR-302通过下调靶基因RAB22A抑制膀胱癌进展

目的:探讨miR-302通过靶向调控RAB22A影响膀胱癌进展的分子机制。方法:采用RT-qPCR检测miR-302在HTB1和RT112膀胱癌细胞系和膀胱内皮细胞系HBdNEC中的表达;以miRNA-NC、miR-302 mimic、miR-302 inhibitor转染细胞,并分为以下几组:NC+control si RNA、miR-302 inhibitor+control si RNA、miR-302 inhibitor+RAB22A si RNA、NC+vector、miR-302 mimic+vector或miR-302 mimic+RAB22A,再通过MTT实验分析膀胱癌细胞的增殖情况,细胞侵袭实验检测细胞侵袭情况,双荧光素酶报告载体检测分析miR-302靶基因,Western blot检测RAB22A在膀胱癌细胞中的表达。结果:HTB1和RT112细胞中miR-302的表达明显低于HBdNEC细胞(P0.05)。miR-302高表达抑制膀胱癌细胞的增殖和侵袭;miR-302低表达时,膀胱癌细胞的增殖和侵袭能力上升。生物信息学和双荧光素酶报告结果显示RAB22A为miR-302的靶基因。miR-302过表达后,细胞荧光素酶活性显著下降(P0.05),RAB22A表达下调(P0.05);miR-302表达沉默后,细胞荧光素酶活性显著上升(P0.05),RAB22A表达上调(P0.01)。拯救实验显示RAB22A表达沉默可逆转miR-302表达沉默时对膀胱癌细胞增殖和侵袭能力上调的影响;而RAB22A过表达可逆转miR-302过表达对膀胱癌细胞增殖和侵袭的抑制。结论:miR-302可通过抑制靶基因RAB22A的表达,抑制膀胱癌细胞的增殖及侵袭。

MiR-302 Inhibits the Progression of Bladder Cancer by downregulating the Target Gene RAB22A

ABSTRACT Objective: To investigate the molecular mechanism underlying by which miR-302 targeting RAB22A in bladder cancer progression. Methods: The expression of miR-302 in the bladder cell lines HTB1 and RT112 and bladder endothelial cell line HBdNEC was detected by RT-qPCR. miRNA-NC, miR-302 mimic and miR-302 inhibitor were transfected into bladder cancer cells, and divided into the following groups: the NC +control siRNA, miR-302 inhibitor +control siRNA, miR-302 inhibitor +RAB22A siRNA, NC+ vector, miR-302 mimic +vector or miR-302 mimic +RAB22A, respectively. The proliferation was detected by MMT assay, and the invasion was detected by Transwell assay. The dual luciferase reporter assay was performed to verify the target gene of miR-302. And the protein expression of RAB22A in bladder cancer cells was detected by Western blot. Results: The expression of miR-302 in HTB1 and RT112 cells was significantly lower than that in HBdNEC cells. The proliferation and invasion of bladder cancer cells was inhibited by the overexpression of miR-302; While the proliferation and invasion of bladder cancer cells were increased when the expression of miR-302 was silenced. Bioinformatics and dual luciferase reporter results showed that RAB22A was the target gene of miR-302. The activity of cell luciferase and the expression of RAB22A were significantly decreased when miR-302 was overexpressed. However, the activity of cell luciferase and the expression of RAB22A were significantly increased when miR-302 was silenced. The rescue experiments showed that knockdown of RAB22A reversed the increased proliferation and invasion abilities of bladder cancer cells induced by miR-302 inhibitor. Overexpression of RAB22A reversed the inhibition on the proliferation and invasion of bladder cancer cells when miR-302 was overexpressed. Conclusion: miR-302 inhibits the proliferation and invasion of bladder cancer cells by inhibiting the expression of target gene RAB22A.