LncRNA AC098934 promotes proliferation and invasion in lung adenocarcinoma cells by combining METTL3 and m6A modifications

Background: Long non-coding RNA (lncRNA) regulates the tumorigenesis as well as the development of lung adenocarcinoma (LUAD), which is one of the high-mortality cancers. We explored the influence of lncRNA AC098934 on the malignant biological behavior of LUAD and potential underlying molecular mechanisms. Methods: The expression level of AC098934 in either the LUAD or the normal tissues was identified in the TCGA database. Two AC098934 knockdown siRNAs were infected into cells of LUAD, including A549 as well as H1299 cells, using the lentivirus. Real-time Quantitative polymerase chain reaction (QPCR) helped to determine the knockdown efficiency of AC098934. CCK-8, cell cloning, wound healing combined with transwell assays tested the role of AC098934 in the cell proliferation, migration as well as the invasion. Tumor formation experiment in nude mice subcutaneously confirmed the promoting effect of AC098934 in vivo. In addition, combinations of METTL3 and AC098934, as well as m6A and AC098934 were identified through the RIP assay. Results: Compared to the normal tissues, AC098934 was more highly expressed in LUAD tissues. After AC098934 was knocked down by siRNA, the proliferation, invasion, migration as well as tumorigenesis abilities of both A549 and H1299 cells were reduced. Mechanistically, AC098934 could bind to the m6A antibody and METTL3 protein. METTL3 overexpression promoted the m6A modification on AC098934, thereby increasing the interaction of m6A modification. Conclusion: The highly expressed lncRNA AC098934 in LUAD facilitates the cell proliferation as well as invasion either in vitro or in vivo. METTL3 binds, furthermore, modulates the m6A modification of AC098934. Our research revealed a new molecular mechanism, through which AC098934 promoted the malignant behavior of LUAD tumors under the m6A modification induced by METTL3. This indicates that AC098934 is possible to be a promising biomarker as well as a therapeutic target for the patients with LUAD.