MiR-20a靶向调控MICA对乳腺癌细胞恶性生物学行为及IFN-γ和TNF-α的影响

Effects of miR-20a targeted regulation of MICA on the malignant biological behavior of breast cancer cells and the IFN-γand TNF-α

目的探究miR-20a靶向调控肿瘤细胞表面主要组织相容性复合体Ⅰ类链相关分子A(MICA)对乳腺癌细胞恶性生物学行为及干扰素-γ(IFN-γ)和肿瘤坏死因子-α(TNF-α)的影响。方法将乳腺癌细胞MCF-7通过转染分为对照组、miR-20a mimics组、miR-20a inhibitor组。RT-qPCR检测miR-20a的表达,分别对各组细胞的增殖和侵袭能力及凋亡情况进行检测,测定IFN-γ和TNF-α水平。通过双荧光素酶报告来验证miR-20a与MICA的靶向关系。Western blot检测MICA蛋白的表达。结果MiR-20a mimics组细胞的miR-20a水平、增殖和侵袭能力显著高于对照组(P<0.05),细胞凋亡率、MICA蛋白、IFN-γ和TNF-α水平显著低于对照组(P<0.05);miR-20a inhibitor组细胞的miR-20a水平、增殖和侵袭能力显著低于对照组(P<0.05),细胞凋亡率、MICA蛋白、IFN-γ和TNF-α水平显著高于对照组(P<0.05)。双荧光素酶报告实验结果显示,miR-20a和MICA之间存在靶向结合。结论MiR-20a可能通过靶向MICA蛋白促进乳腺癌细胞的增殖和侵袭,并抑制IFN-γ和TNF-α的表达。

Objective To explore the effects of miR-20a targeted regulation of major histocompatibility complexclass I-chain related A(MICA)on the malignant biological behavior of breast cancer cells and the interferon-γ(IFN-γ)and tumor necrosis factor-α(TNF-α).Methods Breast cancer cells MCF-7 were divided into the control group,the miR-20a mimics group and the miR-20a inhibitor group by transfection.RT-qPCR was used to detect the expression of miR-20a.The proliferation,invasion and apoptosis of cells in each group were detected,and the levels of IFN-γand TNF-αwere measured.Dual luciferase reporter assay was used to verify the targeting relationship between miR-20a and MICA.The expression of MICA protein was detected by Western blot.Results The miR-20a level,proliferation and invasion abilities of the miR-20a mimics group were significantly higher than those of the control group(P<0.05),and the apoptosis rate and levels of MICA protein,IFN-γand TNF-αwere significantly lower than those of the control group(P<0.05).The miR-20a level,proliferation and invasion abilities of the miR-20a inhibitor group were significantly lower than those of the control group(P<0.05),and the apoptosis rate and levels of MICA protein,IFN-γand TNF-αwere significantly higher than those of the control group(P<0.05).Dual luciferase reporter assay results showed that there was targeted binding between miR-20a and MICA.Conclusion MiR-20a may promote the proliferation and invasion of breast cancer cells,and inhibit the expression of IFN-γand TNF-αby targeting MICA protein.