微小RNA-34a通过靶向CD44调节膀胱癌细胞J82周期

Micro RNA-34a regulates cell cycle by targeting CD44 in human bladder carcinoma cells

目的观察微小RNA-34a(miR-34a)对膀胱癌细胞J82周期的影响,并探索其中的机制。方法于J82中转染miR-34a前体或miR-34a抑制物并验证转染效率,结合此前研究报道和生物信息学预测miR-34a的靶点,后通过荧光素酶报告实验验证miR-34a靶标基因CD44,通过Western blot和实时定量PCR方法检测CD44及其周期相关蛋白及信使RNA表达水平的变化,利用流式细胞仪检测膀胱癌细胞J82周期的变化。结果 miR-34a在膀胱癌细胞J82和组织中表达下调,转染miR-34a前体和抑制物后,获得满意的转染效果;双荧光素酶报告实验证实miR-34a对CD44的3'UTR活性显著调节,并伴随相关周期相关因子表达水平变化,同时观测到其对膀胱癌细胞J82周期的影响。miR-34a mimics明显降低膀胱癌细胞J82中CD44的表达,miR-34a inhibitor明显上调膀胱癌细胞J82中CD44的表达;CD44可以部分回复mir-34a对膀胱癌细胞J82周期的影响。结论微小RNA-34a通过直接靶向CD44调节膀胱癌细胞J82周期的变化。

Objective To investigate the role of microRNA-34a （miR-34a） in regulating the cell cycles of bladder cancer cell line J82 and explore the underlying mechanism. Methods J82 cells were transfected with a miR-34a mimic or an inhibitor to induce miR-34a overexpression or silencing. The RNA level of miR-34a in the transfected cells was detected by real-time PCR, and CD44 expressions at the mRNA and protein levels were detected by real-time PCR and Western blotting. Luciferase reporter assay was used to detect the activation of 3＆#39;UTR of CD44, and flow cytometry was performed to analyze the cell cycle changes. Results The expression level of miR-34a was significantly increased and CD44 expression significantly lowered in cells transfected with miR-34a mimic; miR-34a inhibitor transfection caused reverse effects on miR-34a and CD44 expressions. MiR-34a mimics downregulated while miR-34a inhibitor enhanced the activation of 3＆#39;UTR of CD44 with corresponding changes in the expressions of some cell cycle-related proteins. MiR-34a mimics and miR-34a inhibitor induced opposite changes in J82 cell cycle, which were partly reversed by CD44. Conclusion MiRNA-34a regulates cell cycles by targeting CD44 in human bladder carcinoma cell line J82.