The long noncoding RNA LINC00341 suppresses colorectal carcinoma by preventing cell migration and apoptosis

Abstract

Long noncoding RNAs (lncRNAs) are ubiquitous transcripts that play key roles in regulating gene expression at the levels of transcription, RNA processing, and translation. Aberrant expression and mutations of lncRNAs represent a driving force behind oncogenesis and development of tumours. However, most of the lncRNAs are still being undiscovered, and conclusive experimental evidence for their functional relevance continues to be lacking for most malignancies. We have found that lncRNA long intergenic non-protein-coding RNA 341 (LINC00341) is aberrantly downregulated by microarray-based screenings on nonmetastatic and metastatic colorectal carcinoma (CRC) specimens; LINC00341 is a novel long intergenic non-protein-coding RNA with unknown functions. LINC00341 overexpression restricts tumour growth and promotes its apoptosis. Instead, LINC00341 silencing accelerates CRC cell proliferation and migration. RNA-pulldown assay identifies LINC00341 physically binds to HMGB2 and stabilizes the localization of HMGB2 in the cytoplasm. Notably, LINC00341 knockdown leads to the shift of HMGB2 into nuclear, in which it triggers epithelial to mesenchymal transition (EMT) programming. Moreover, LINC00341 can also promote apoptosis. SIGNIFICANCE OF THE STUDY: LncRNAs are ubiquitous transcripts that play key roles in regulating gene expression at the levels of transcription, RNA processing, and translation. Aberrant expression and mutations of lncRNAs represent a driving force behind oncogenesis and development of tumours. However, the function of lncRNA still needs further exploration. Our study has revealed a new noncoding RNA-mediated regulatory network that highly likely protects colorectal carcinoma by preventing migration and apoptosis. The results will help further explore the molecular details about the progression of colorectal carcinoma and stimulate efforts to develop effective therapies.

Keywords: HMGB2; LINC00341; apoptosis; colorectal carcinoma; lncRNA; migration.