miR34c

miR-34c is a microRNA in the miR-34 family, produced from the MIR34C gene. It is part of a cluster that also gives rise to miR-34b and shares regulatory and functional characteristics with its family members. Like other microRNAs, miR-34c functions by guiding the RNA-induced silencing complex to target mRNAs, leading to translational repression or mRNA degradation. The mature miR-34c is generated as two strands, miR-34c-5p and miR-34c-3p, each capable of post-transcriptional regulation.

Regulation and biogenesis of miR-34c are closely linked to cellular stress responses. The miR-34 family is transcriptionally activated by the tumor suppressor protein p53 in response to DNA damage or oncogenic stress, placing miR-34c within the p53-dependent anti-tumor pathway. This regulation helps coordinate cell fate decisions under stress.

Functional role and targets of miR-34c are diverse, with a focus on tumor suppression. miR-34c inhibits cell proliferation and promotes apoptosis and senescence by targeting multiple genes involved in growth and survival, including BCL2, CDK4, CDK6, MET, NOTCH1, and SIRT1. Through these and other targets, miR-34c can reduce cell cycle progression, suppress migration and invasion, and modulate epithelial-mesenchymal transition in various cell types.

Clinical relevance is primarily in oncology. miR-34c expression is often reduced in cancers, and restoration of its levels has shown anti-tumor effects in preclinical models. Its stability in body fluids has spurred interest as a potential biomarker, while therapeutic approaches using miR-34 mimics have been explored, though clinical development faces delivery and safety considerations.