MicroRNA 199b (miR-199b)

MicroRNA 199b is a small, non-coding RNA (miRNA) molecule involved in post-transcriptional regulation of gene expression by binding to complementary sequences in target mRNAs, resulting in their degradation or translational inhibition. It plays a complex and context-dependent role in tumorigenesis—acting as either a tumor suppressor or an oncogene in different tissues and cancers. In gastric and colon cancer, miR-199b promotes cell proliferation, migration, and the epithelial-mesenchymal transition (EMT) by targeting genes such as HHIP and FZD6, while it exhibits suppressive effects in breast cancer and certain types of leukemia. Deregulation of miR-199b has also been associated with drug resistance in cancer treatment and with alterations in extracellular matrix metabolism in cartilage pathology. Its utility as a biomarker in diagnosis, prognosis, and therapy monitoring is actively being explored[1][2][3][4][5][7][9].

Other names

MIR199Bhsa-mir-199bMIRN199Bmir-199bmicroRNA 199bMI199B

MicroRNA 199b functions primarily through post-transcriptional suppression of oncogenes and tumor suppressors by direct mRNA binding and destabilization. It can sensitize or confer resistance to chemotherapy by regulating downstream pathways such as JAG-Notch1 and PAK4/MEK/ERK signaling. Furthermore, miR-199b modulates epithelial-mesenchymal transition (EMT) by targeting HHIP and FZD6, and in chondrocytes, it inhibits cell viability and promotes extracellular matrix degradation.