Comprehensive long-read transcriptomic analysis reveals multi-level transcriptional alterations mediated by miR-214-3p dysregulation in gastric cancer cells

Long-length sequencing has been widely used in cancer-related research for exploring transcriptome variations in human cancer in recent years. miR-214-3p, a microRNA, has been reported to have abnormal expression and play important regulation roles in diverse cancers. However, information about the genome-wide targets and action mechanisms of miR-214-3p in cancer cells is still limited. Here, long-read sequencing were performed to character the transcriptome variations after disturbing the expression of miR-214-3p in AGS cells, a gastric cancer cell line. The results showed that both miR-214-3p overexpression (OE) and suppression (KD) extensively increased or decreased expression level of a number of genes involved in apoptotic process and transcription at transcript level and gene level. In particular, both miR-214-3p KD and OE could increase or decrease on the expression levels of some target genes at the same direction. Moreover, miR-214-3p broadly regulated the alternative splicing of hundreds of genes with functions of cell division, cellular senescence and transcription regulation. In addition, the changes in the expression level of miR-214-3p can cause changes in the alternative polyadenylation and 3UTR lengths of the transcript. Taken together, these results indicated that miR-214-3p could mediate apoptosis by diverse modes in AGS cells, which adds to the understanding of the critical role of miR-214-3p in cancer cancer.