长链非编码RNA MYLK-AS1通过介导RNA甲基化调控细胞焦亡促进非小细胞肺癌发生的机制研究

肺癌在癌症相关死亡疾病中居首位，深入探讨肺癌发生机制对改善患者预后至关重要。研究表明lncRNAs与非小细胞肺癌（NSCLC）的发生密切相关。申请人前期研究发现组蛋白修饰激活的lncRNA MYLK-AS1在NSCLC中异常高表达且促进肺癌发生。RNA pull down联合质谱、RIP实验证实MYLK-AS1可绑定m6A甲基化转移酶METTL3。进一步分析发现MYLK-AS1调控细胞焦亡关键基因GSDMD表达。故提出假说：组蛋白修饰异常激活MYLK-AS1导致其在肺癌中高表达，MYLK-AS1通过绑定RNA甲基化转移酶METTL3，介导RNA m6A甲基化修饰转录后表观抑制GSDMD表达，调控细胞焦亡，形成肺癌细胞抗焦亡表型，从而促进NSCLC细胞的恶性进展。本课题拟从细胞、活体动物和组织样本层面阐明lncRNA MYLK-AS1参与NSCLC发生的新机制，为临床治疗提供理论依据。

Lung cancer is the predominant cause of cancer-related death worldwide. Hence, exploration of the molecular mechanisms involved in the progression of lung cancer is critical to improving patient outcomes. Studies have confirmed that lncRNAs could play important roles in NSCLC tumorigenesis. Our previous study found that MYLK-AS1 was significantly up-regulated in non-small cell lung cancer (NSCLC) and promoted NSCLC cells malignant progression through lncRNA sequencing, clinical tissue verification and cell biology experiments. The results of bioinformatic analysis and ChIP assays showed that histone modification activated- MYLK-AS1 was upregulated in NSCLC. Moreover, RNA pull-down combined with mass spectrometry, RIP assays found that MYLK-AS1 could bind to m6A methyltransferase METTL3. RNA-seq analysis revealed that the knockdown of MYLK-AS1 could increase the expression of GSDMD. Calcein-AM staining showed that knockdown of MYLK-AS1 or METTL3 induced NSCLC cells pyroptosis. Consequently, we hypothesized that histone modification activated-MYLK-AS1 regulates pyroptosis by medicating RNA methylation, thus promoting the progression of NSCLC. Therefore, the purpose of this study is to explore the new mechanism of MYLK-AS1 regulating the tumorigenesis of NSCLC at cellular, in vivo and tissue levels, and provide potential biological targets and theoretical basis for clinical treatment.