MicroRNA 18b (miR-18b)

MicroRNA 18b (miR-18b) is a small non-coding RNA molecule of approximately 22 nucleotides that functions as a post-transcriptional regulator of gene expression through binding to complementary sequences on target mRNAs, leading to translational repression or mRNA destabilization. Encoded within the miR-106a-363 cluster on chromosome X, miR-18b is aberrantly regulated in several pathological states, particularly in cancers such as breast cancer, where it shows substantial upregulation in tumor tissues compared to normal tissues[4]. miR-18b influences important cellular processes including apoptosis, cell proliferation, differentiation, and cell migration, partly by regulating genes such as HIF1A, MEF2C, BAX, BCL2, and others involved in tumor biology[1][4]. Elevated miR-18b expression is strongly associated with highly proliferative, estrogen receptor-negative breast tumors and with immune cell infiltration, especially macrophages, suggesting a role in the tumor microenvironment and immune modulation. While miR-18b is increasingly recognized as a potential biomarker for patient stratification and prognosis, especially in cancer[4][7], direct therapeutic targeting remains experimental, largely limited by the complexity of microRNA biology and delivery[4][7][3].

Other names

hsa-mir-18bMIRN18BMIR18Bmir-18bmicroRNA-18b-5p