LncRNA H19/miR-141/PD-L1轴介导EGFR突变型非小细胞肺癌免疫逃逸的作用及机制研究

Programmed death ligand-1（PD-L1）is vital for immune escapes in non-small cell lung cancer(NSCLC) and proved inducible by EGFR mutation. Evidence shows that microRNA is also involved in regulating tumor immune evasion. Nevertheless, whether microRNA influence the expression of PD-L1 on tumor cells remains elusive. In our prophase research, the expression level of miR-141 and PD-L1 were reversely correlated with significant statistical difference. Morever, the expression of PD-L1 may be post-transcriptionally regulated by miR-141. Long non-coding RNA（lncRNA）H19 shares a common binding sequences with PD-L1 on the untranslated region of miR-141，which indicates that H19 may function as a competitive endogenous RNA (ceRNA) and therefore relieve the translational suppression on PD-L1 by miR-141. To validate our hypothesis that lncRNA-H19/miR-141/PD-L1 axis is a novel mechanism regulating tumor immune evasion, we design to moderate the expression level of lncRNA H19 and miR-141 and apply routine techniques including western blot, RNA co-immunoprecipitation and luciferase reporter gene. Moreover, we would investigate the therapeutic potential by targeting H19 and miR-141 with subcutaneously implanted tumor model. The proposed study is innovative as it may illustrate a new regulating mechanism for tumor immune and provide potential target for treatment EGFR mutant NSCLC by blocking tumor immune escape.

研究发现，在NSCLC中，驱动基因EGFR突变可上调PD-L1表达、促进肿瘤免疫逃逸。近年来研究发现，microRNA可参与肿瘤免疫逃逸，但对PD-L1的调控仍有待进一步研究。课题组前期研究发现miR-141可能在转录后水平调控NSCLC肿瘤细胞PD-L1的表达，而lncRNA H19与PD-L1共享一段miR-141非编码区的结合序列，提示H19可能通过“竞争性内源性RNA”的机制解除miR-141对PD-L1的翻译抑制、促进肿瘤免疫逃逸。课题组拟通过干预H19和miR-141表达水平，通过免疫印迹、RNA免疫共沉淀、荧光素酶报告基因等实验技术，阐明lncRNA-H19/miR-141/PD-L1轴调节EGFR突变型肺癌免疫逃逸的机制，并通过体内实验验证靶向H19、miR-141对抑制肿瘤免疫逃逸的治疗潜力。本课题有望为深入理解和克服EGFR突变型肺癌免疫逃逸提供研究基础。

研究发现，在NSCLC中，驱动基因EGFR突变可上调PD-L1表达、促进肿瘤免疫逃逸。近年来研究发现，microRNA可参与肿瘤免疫逃逸，但对PD-L1的调控仍有待进一步研究。课题组研究发现miR-141在转录后水平调控NSCLC肿瘤细胞PD-L1的表达，而lncRNA H19与PD-L1共享一段miR-141非编码区的结合序列。课题组通过干预H19和miR-141表达水平，通过免疫印迹、RNA免疫共沉淀、荧光素酶报告基因等实验技术，证实H19通过“竞争性内源性RNA”的机制解除miR-141对PD-L1的翻译抑制、促进肿瘤免疫逃逸，阐明了lncRNA-H19/miR-141/PD-L1轴调节EGFR突变型肺癌免疫逃逸的机制，为探索EGFR突变型肺癌免疫逃逸提供了一定的研究基础。