miRNA-34a靶向调控叉头框蛋白P1对活化B细胞样弥漫性大B细胞淋巴瘤细胞凋亡的影响

Molecular mechanism of targeted regulation of FOXP1 by miRNA-34a in the apoptosis of ABC-DLBCL cells

目的探讨miRNA-34a靶向调控叉头框蛋白P1(FOXP1)对活化B细胞样弥漫性大B细胞淋巴瘤(ABC-DLBCL)细胞凋亡的影响。方法将miRNA-34a mimics转染至SU-DHL-2细胞并验证转染效率,检测miRNA-34a过表达对SU-DHL-2细胞增殖和凋亡的影响。采用逆转录聚合酶链反应(RT-PCR)和Western blot法分别检测SU-DHL-2细胞转染miRNA-34a mimics后FOXP1 mRNA和FOXP1蛋白表达水平的变化。通过双荧光素酶报告实验验证miRNA-34a和FOXP1的相互作用机制。验证FCXP1 siRNA转染至SU-DHL-2细胞的转染效率,通过CCK8法和流式细胞仪检测FOXP1基因沉默对SU-DHL-2细胞增殖及凋亡的影响。结果SU-DHL-2细胞转染miRNA-34a mimics和FOXP1 siRNA后均获得满意的转染效果。miRNA-34a过表达明显降低了SU-DHL-2细胞中FOXP1 mRNA和FOXP1蛋白的相对表达量。miRNA-34a对FOXP13’非翻译区(3’-UTR)具有直接调控作用。miRNA-34a过表达组和FOXP1基因沉默组细胞凋亡率均明显高于NC组细胞,差异均有统计学意义(P<0.01)。miRNA-34a过表达和FCXP1基因沉默对细胞增殖能力没有影响。结论miRNA-34a抑制ABC-DLBCL细胞的发生发展可能与miRNA-34a通过结合FOXP13’-UTR有效抑制FOXP1蛋白表达进而促进肿瘤细胞凋亡有关。

Objective To investigate the effect of miRNA-34a on apoptosis of activated B-cell diffuse large B-cell lymphoma(ABC-DLBCL)cells by targeting forkhead box P1(FOXP1).Method miRNA-34a mimics were transfected into SU-DHL-2 cells and the transfection efficiency was verified.The effect of overexpression of miRNA-34a on proliferation and apoptosis of SU-DHL-2 cells were detected.Changes in FOXP1 mRNA and protein expression levels in SUDHL-2 cells after transfection with miRNA-34a mimics were detected by RT-PCR and Western blot assay,respectively.The interaction mechanism between miRNA-34a and FOXP1 was verified by the dual-luciferase reporter assay system.The transfection efficiency of FOXP1 siRNA to SU-DHL-2 cells was verified.The effect of FOXP1 gene silencing on the proliferation and apoptosis of SU-DHL-2 cells was detected by CCK8 method and flow cytometry.Result SU-DHL-2 cells were transfected with miRNA-34a mimics and FOXP1 siRNA with satisfactory transfection results.The overexpression of miRNA-34a significantly reduced the expression levels of FOXP1 mRNA and protein in SU-DHL-2 cells.miRNA-34a directly regulated FOXP13'-untranslated region(3'-UTR).The apoptosis rates of the miRNA-34a overexpression group and the FOXP1 gene silencing group were significantly increased compared with the negative control group.miRNA-34a overexpression and FOXP1 gene silencing had no effect on cell proliferation ability.Conclusion The cytogenesis and development of ABC-DLBCL cells inhibited by miRNA-34a may be related to the effective inhibition of FOXP1 protein expression by miRNA-34a binding to FOXP13'-UTR,thereby promoting tumor cell apoptosis.