Aberrant DNA hypermethylation-silenced LINC00886 gene accelerates malignant progression of laryngeal carcinoma

Abstract

BackgroundLong noncoding RNAs (lncRNAs) play crucial role in formation and progression of tumors. DNA methylation has become increasingly recognized as a frequent event of epigenetic alterations and one of the primary mechanisms of gene inactivation. The research aims to investigate the biofunction of a novel lncRNA in LSCC. MethodsqRT-PCR, BGS, and MSP methods were employed to measure the relative expression level and methylation status of LINC00886. Additionally, we examined the effects of LINC00886 on cells proliferation and invasion using LINC00886 over-expression. Nude mouse xenograft models were conducted to assess LINC00886 effects on LSCC growth in vivo. High-throughput sequencing technology and Western blot assay were carried out to have an in-depth study of the downstream target genes and signaling pathways in which LINC00886 may participate. ResultsThe remarkable downregulation of LINC00886 was observed in tumor tissues and laryngeal cancer cell lines. The significant decrease of LINC00886 was correlated with pathological grade in LSCC tissues. The expression level of LINC00886 in laryngeal cancer cell lines was significantly reversed by 5-Aza-dC. The occurrence of aberrant methylation events in the LINC00886 TSS was more responsible for the down-expression of LINC00886. Over-expression of LINC00886 dramatically mitigated cell proliferation, migration, and invasion in vitro as well as suppressed tumor growth in vivo. LINC00886 may be associated with VEGFA/PI3K/AKT signaling pathways and epithelial-mesenchymal transition (EMT) process. ConclusionsWe provide the first evidence of the involvement of LINC00886 in laryngeal carcinoma, which was downregulated due to methylation of the promoter region and served as tumor suppressor genes. LINC00886 is expected to become a novel biomarker in laryngeal carcinoma.