MicroRNA 155-5p (miR-155-5p)

MicroRNA 155-5p (miR-155-5p) is a highly conserved, multifunctional non-coding RNA that serves as a master regulator of the immune system and hematopoiesis (NIH, 2022). It is processed from the B-cell integration cluster (BIC) transcript and is predominantly expressed in activated B cells, T cells, and macrophages (Biovendor, 2021). In its physiological role, miR-155-5p modulates the intensity of the immune response by post-transcriptionally silencing over 140 target genes, including SHIP1 and SOCS1, which are critical negative regulators of inflammatory signaling (MDPI, 2020). Pathological overexpression of miR-155-5p is a hallmark of several hematological malignancies, such as diffuse large B-cell lymphoma and cutaneous T-cell lymphoma, where it functions as an oncomir to promote cell survival and proliferation (ResearchGate, 2025). Additionally, it is implicated in the pathogenesis of autoimmune and inflammatory disorders, including multiple sclerosis and rheumatoid arthritis, by driving pro-inflammatory cytokine production (NIH, 2025). Therapeutic intervention typically involves the use of antisense oligonucleotides, such as Cobomarsen (MRG-106), which competitively bind to the mature miRNA to derepress its target genes and inhibit oncogenic or inflammatory pathways (MedChemExpress, 2021). Despite its therapeutic potential, challenges such as off-target effects and the complexities of systemic delivery remain significant hurdles in clinical development.

Other names

hsa-miR-155-5pMIR155B-cell integration clusterBICmiR-155

Antisense oligonucleotide inhibition; the drug (antagomir) competitively binds to the mature miR-155-5p sequence, preventing it from interacting with its target mRNAs, thereby derepressing the expression of tumor suppressor or anti-inflammatory proteins (NIH, 2018; ClinicalTrials.gov, 2021).