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.
The gene for miR-15a is located on the chromozome 13q14.
Functional studies have reported that miR-15a positively regulates pancreatic β-cell function and insulin synthesis and negatively affects adipogenesis. It was also shown that miR-15a is increased in plasma of diabetic patients, correlating with disease severity.
miR-15a is downregulated in many types of cancer, including prostate cancer, colorectal cancer, hepatoma, prostate cancer, chronic lymphocytic leukemia, nasopharyngeal carcinoma, malignant melanoma, human brain glioma and breast cancer. It acts as a tumor suppressor, promoting apoptosis and inhibiting cell proliferation by targeting multiple oncogenes, including Bcl-2, Mcl1, CcnD1 and Wnt3A.
Besides cancer, circulating miR-15a is downregulated in patients with ST-segment elevated myocardial infarction, compared to healthy controls.
- References to miR-15a-5p