microRNA 138-2 (miR-138-2)

microRNA 138-2 is one of two loci encoding the mature miR-138, a small non-coding RNA involved in the post-transcriptional regulation of gene expression. It functions by binding target mRNAs, leading to their silencing via degradation or inhibition of translation. miR-138-2 is transcribed from a unique DNA locus independently regulated by transcription factors such as C/EBPβ. The mature miR-138 plays key roles in cancer biology, notably as an oncomiR in triple-negative breast cancer and glioma, where it promotes cell survival, proliferation and metastasis, partly by silencing pro-apoptotic and tumor suppressor genes such as TUSC2 and FAK. Its expression levels can serve as biomarkers of disease progression and prognosis, and it is viewed as a promising target for oligonucleotide-based therapies, although no approved drugs currently target it directly. Safety concerns remain, primarily due to the pleiotropic nature of microRNAs and delivery challenges.

Other names

miR-138-2hsa-miR-138-2MIRN138-2mir-138-2MIR138-2

Inhibition of miR-138-2 by antisense oligonucleotides leads to derepression of pro-apoptotic and tumor suppressor genes (e.g., TUSC2). miR-138-2 mimics lead to suppression of those genes, affecting pathways such as AKT/mTOR, focal adhesion kinase (FAK), and epithelial-mesenchymal transition.