Methyltransferase 3, N6-adenosine-methyltransferase complex catalytic subunit-induced long intergenic non-protein coding RNA 1833 N6-methyladenosine methylation promotes the non-small cell lung cancer progression via regulating heterogeneous nuclear ribonucleoprotein A2/B1 expression

Long intergenic non-protein coding RNA 1833 (LINC01833) exhibits elevated expression in the non-small cell lung cancer (NSCLC) tissues, while its molecular mechanism in NSCLC progression remains elusive. Herein, the proliferation, migration, invasion as well as apoptosis of NSCLC cells were assessed. The potential N6-methyladenosine (m6A) modification site was predicted by the m6aVar tool. RNA pulldown and m6A-specific immunoprecipitation assays were used to detect the interaction between LINC01833 and methyltransferase 3, N6-adenosine-methyltransferase complex catalytic subunit (METTL3). RNA pull-down together with mass spectrometry were performed to assess the binding relationship between LINC01833 and heterogeneous nuclear ribonucleoprotein A2/B1 (HNRNPA2B1) in NSCLC. Tumor xenograft mice model was established, and the tumor size and weight were measured. The results demonstrated that LINC01833 expression was elevated in NSCLC samples. Overexpression of LINC01833 promoted proliferative, migratory, and invasive abilities and inhibited HCC827 cell apoptosis. LINC01833 knockdown inhibited tumor growth in mice. LINC01833 is further demonstrated to be modulated by METTL3, which is highly expressed in NSCLC samples. In addition, RNA pulldown and m6A-specific immunoprecipitation assays indicated that LINC01833 might form a complex with HNRNPA2B1. In conclusion, m6A transferase METTL3-induced LINC01833 m6A methylation promotes NSCLC progression through modulating HNRNPA2B1 expression. Our findings indicated that LINC01833 might be a therapeutic target for NSCLC.

长链基因间非蛋白编码RNA 1833（Long intergenic non-protein coding RNA 1833, LINC01833）在非小细胞肺癌（non-small cell lung cancer, NSCLC）组织中呈高表达，但其在非小细胞肺癌进展中的分子机制仍未阐明。本研究检测了非小细胞肺癌细胞的增殖、迁移、侵袭及凋亡水平。通过m6aVar工具预测潜在的N6-甲基腺嘌呤（N6-methyladenosine, m6A）修饰位点。采用RNA下拉实验与m6A特异性免疫沉淀实验，探究LINC01833与甲基转移酶3、N6-腺苷甲基转移酶复合物催化亚基（methyltransferase 3, N6-adenosine-methyltransferase complex catalytic subunit, METTL3）的相互作用。通过RNA下拉联合质谱分析，评估LINC01833与异质性核核糖核蛋白A2/B1（heterogeneous nuclear ribonucleoprotein A2/B1, HNRNPA2B1）在非小细胞肺癌中的结合关系。构建肿瘤异种移植小鼠模型，检测肿瘤体积与重量。结果显示，LINC01833在非小细胞肺癌样本中表达上调。过表达LINC01833可增强HCC827细胞的增殖、迁移及侵袭能力，并抑制其凋亡。敲低LINC01833可抑制小鼠体内肿瘤生长。进一步研究证实，LINC01833受在非小细胞肺癌样本中高表达的METTL3调控。此外，RNA下拉实验及m6A特异性免疫沉淀实验表明，LINC01833可能与HNRNPA2B1形成复合物。综上，m6A转移酶METTL3诱导的LINC01833 m6A甲基化可通过调控HNRNPA2B1的表达促进非小细胞肺癌进展。本研究结果提示，LINC01833或可成为非小细胞肺癌的潜在治疗靶点。