Phosphoinositide-3-kinase regulatory subunit 2 mRNA 3' untranslated region (PIK3R2 mRNA 3' UTR)

The Phosphoinositide-3-kinase regulatory subunit 2 (PIK3R2) mRNA 3' untranslated region (3' UTR) is a critical regulatory segment of the PIK3R2 transcript, which encodes the p85-beta regulatory subunit of Class IA PI3Ks (UniProt P48567). This region contains multiple binding sites for microRNAs (miRNAs) such as miR-126, miR-497, and miR-135a, which post-transcriptionally regulate PIK3R2 expression by promoting mRNA decay or inhibiting translation (Yuan et al., 2013, PMID: 23563283). In many human malignancies, including breast, lung, and colorectal cancers, the downregulation of these regulatory miRNAs leads to the pathological overexpression of PIK3R2, which in turn constitutively activates the PI3K/Akt/mTOR signaling pathway, driving tumor growth, metastasis, and drug resistance (Wang et al., 2015, PMID: 25605118). Consequently, the PIK3R2 mRNA 3' UTR is considered a significant therapeutic target for RNA-based interventions, including miRNA mimics and antisense oligonucleotides, aimed at restoring normal PI3K signaling. Research indicates that targeting this region can effectively suppress oncogenic phenotypes and sensitize cancer cells to chemotherapy (PubMed 23563283, 25605118).

Other names

PI3K p85-beta mRNA 3' UTRP85B mRNA 3' UTRPhosphatidylinositol 3-kinase regulatory subunit beta mRNA 3' UTRPIK3R2 3'-UTR

Binding of microRNA mimics or antisense oligonucleotides to specific seed sequences within the 3' UTR triggers the RNA-induced silencing complex (RISC) to mediate mRNA degradation or translational repression, thereby reducing PIK3R2 protein levels and suppressing the PI3K/Akt signaling pathway.