miR-182靶向抑制FBXW7表达影响非小细胞肺癌细胞增殖研究

MiR-182 Promotes Cell Proliferation of Non-small Cell Lung Cancer by Suppressing FBXW7

目的:研究microRNA-182(miR-182)在非小细胞肺癌(NSCLC)组织中的表达,并探讨其对NSCLC细胞增殖的影响及作用机制。方法:采用实时荧光定量PCR (qRT-PCR)检测miR-182在11例NSCLC及相应癌旁组织中的表达情况;Western blot检测FBXW7,c-Jun,c-Myc及cyclin D蛋白的表达;将miR-182模拟物,抑制物及相应空白对照瞬时转染H460细胞后,以细胞增殖与活性检测和克隆形成实验检测细胞系的增殖情况;流式细胞术检测细胞周期和凋亡变化;荧光素酶报告基因实验证实miR-182对FBXW7的靶向性作用。结果:NSCLC组织中miR-182的相对表达水平显著高于癌旁组织(P<0.05)。转染组与对照组相比,H460细胞生长、克隆形成能力显著增强,细胞周期进程加快,细胞凋亡受到抑制(P<0.05)。在NSCLC组织中,FBXW7蛋白的表达水平明显低于癌旁组织(P<0.05)。miR-182 mimics显著降低野生型FBXW7质粒荧光素酶的活性,然而将结合位点突变后,miR-182 mimics则不再影响荧光素酶的活性。结论:miR-182在NSCLC组织中高表达,与FBXW7之间存在靶向关系,通过下调FBXW7蛋白表达促进NSCLC细胞的增殖,参与肿瘤的发生发展,预示其可能成为一种潜在的生物标志和治疗靶点。

Objective: To investigate the expression of microRNA-182(miR-182) in the non-small cell lung cancer(NSCLC)tissues and its effect and mechanism on the proliferation of NSCLC cells. Methods: The expression of miR-182 in the malignant NSCLC tissue and adjacent normal tissue was estimated by quantitative reverse-transcription polymerase chain reaction(qRT-PCR). The Levels of FBXW7 and corresponding substrates were detected by western blot. Cell growth was detected by counting kit(CCK)-8 reagent and colony formation experiment. Cell cycle progression and cell apoptosis were determined through flow cytometry. The effect of miR-182 on the FBXW7 was determined using the Dual-Luciferase Reporter Assay System. Results: Compared with the adjacent normal tissues,the expression of miR-182 was significantly upregulated in the NSCLC tissues(P<0.05). Compared with the control group, the capacity of cell growth, colony formation capacity and cell cycle progression were dramatically increased, the apoptosis was decreased in the transfection group(P<0.05). In addition, the expression of FBXW7 protein was downregulated in the NSCLC tissus(P<0.05). The activity of luciferase in wild-type FBXW7 plasmid was significantly decreased by miRNA-182 mimics. However, the activity of luciferase hadn’t been affected by miRNA-182 mimics after mutation of binding site. Conclusions: The expression of miR-182 was up-regulated in the NSCLC tissues, which can promote the proliferation of NSCLC cells and participates in the occurrence and development of tumors by down-regulating the expression of FBXW7.