miR-320调节人慢性髓系白血病细胞系K562的增殖

目的探讨miR-320对人慢性髓系白血病细胞系K562增殖和细胞周期的影响。方法采用正常人及初诊的慢性髓系白血病患者外周血病单个核细胞,用实时定量PCR检测miR-320和β-cateninmRNA的表达;用miR-320模拟物转染K562细胞,CCK-8法检测细胞增殖;流式细胞计量术检测细胞周期;双荧光报告基因试验和Westernblot检测β-cateninmRNA表达;实时定量PCR检测miR-320模拟物对Wnt/β-catenin信号通路下游基因的转录。结果miR-320在慢性髓系白血病患者中的表达水平显著低于正常人,而β-catenin表达水平显著高于正常人(P<0.05);过表达miR-320可以抑制K562细胞的增殖(P<0.05)和细胞周期的运行;miR-320可抑制靶基因β-catenin的表达,进而抑制Wnt/β-catenin信号通路下游基因c-Myc、cyclinD、VEGF和Cox-2mRNA的表达(P<0.05)。结论miR-320通过调节β-catenin的表达,在慢性髓系白血病中发挥抑癌功能。

miR-320 regulates the proliferation of human chronic myeloid leukemia cell line K562

Objective To investigate the effect of miR-320 on the proliferation and cell cycle progression of human chronic myeloid leukemia(CML) cell line K562. Methods The relative expression of miR-320 and β-catenin was detected in the peripheral blood mononuclear cells(PBMCs) isolated from CML patients and normal controls by using quantitative PCR analysis;K562 cells were transfected with miR-320 mimics or mimic controls. The effects of miR-320 overexpression on K562 cell proliferation were examined by CCK-8 analysis. The effects of miR-320 overexpression on K562 cell cycle progression were examined by FACS analysis. The influence of miR-320 on β-catenin expression was determined by dual-luciferase assay and Western blot analysis. The influence of miR-320 on the downstream targets of Wnt/β-catenin was determined by quantitative PCR. Results The expression of miR-320 was down-regulated in CML patients, whereas the expression of β-catenin was up-regulated. Overexpression of miR-320 reduces K562 cell proliferation and inhibits its cell cycle progression(P<0.05). miR-320 regulated expression of β-catenin and its downstream target genes, including: c-Myc, cyclin D, VEGFand Cox-2(P<0.05). Conclusions miR-320 acts as a tumor suppressor via regulating Wnt/β-catenin in CML.