MicroRNAs (miRNAs) are small non-coding RNA molecules, approximately 22 nucleotides in length that regulate gene translation through silencing or degradation of target mRNAs. They are involved in multiple biological processes, including differentiation and proliferation, metabolism, hemostasis, apoptosis or inflammation, and in pathophysiology of many diseases. Numerous studies have suggested circulating miRNAs as promising diagnostic and prognostic biomarkers of many diseases.
miR-203a has been found to be a crucial regulator involved in various malignancies, such as gastric cancer (GC), nasopharyngeal carcinoma (NPC), breast cancer, lung cancer, liver cancer, and colorectal cancer (CRC). The expression of miR-203a-3p was decreased in NPC tissues and cell lines in comparison with normal nasopharyngeal tissues and cell line. miR-203a-3p suppresses tumor growth and metastasis through targeting LASP1 in NPC. miR-203a-3p was also down-regulated in non-small cell lung cancer (NSCLC) tissues and cells compared with normal tissues and cells. miR-203a-3p together with other three miRNAs (miR-7-5p, miR-145-5p and miR-192-5p) were reported to be down-regulated in hepatocellular carcinoma (HCC), and could inhibit HCC progression by modulating expression of multiple target genes. Decrease of TFF3 was associated with increase of miR-203a-3p in plasma of HCC patients and these molecules displayed potent predictive power for HCC diagnosis. It was published that IGF-1R is a direct co-target of miR-99b-5p/203a-3p that may function as tumor suppressive miRNAs by negatively regulating IGF-1R expression in GC cells. In another study, significant downregulation and proximal promoter methylation of miR-203a and miR-203b in gastric cardia adenocarcinoma (GCA) tissues was found. The methylation status of miR-203a and miR-203b in tumor tissues was negatively correlated with their expression level. GCA patients in stage III and IV with reduced expression or hypermethylation of miR-203a demonstrated poor survival. In conclusion, miR-203a and miR-203b may function as tumor suppressive miRNAs, and reactivation of miR-203a may have therapeutic potential GCA patients. miR-203a-3p also promotes colorectal cancer cell proliferation, colony formation and migration and invasion which suggests that miR-203a-3p may be a novel molecular therapeutic target for CRC.
Up-regulation of miR-203a-3p might inhibit pathological retinal angiogenesis in proliferative diabetic retinopathy (PDR). Expression levels of miR-335-5p, miR-485-5p, miR-16-5p, miR-150-5p, miR-34a-5p, and miR-203a-3p were significantly increased in PBMCs from patients with rheumatoid arthritis (RA) compared with healthy controls.
- References to miR-203a-3p