Phosphoinositide 3-kinase catalytic subunit beta (PIK3CB) (PIK3CB)

Phosphoinositide 3-kinase catalytic subunit beta (PIK3CB), also known as p110β, is a Class IA PI3K enzyme that plays a pivotal role in cellular signaling by converting PIP2 to the second messenger PIP3 (UniProt P42338). In platelets, p110β is specifically required for the stabilization of the integrin αIIbβ3-mediated adhesion, which is essential for thrombus formation under high shear stress (Jackson et al., Nature Medicine, 2005). Unlike other Class IA isoforms, p110β is uniquely regulated by both G protein-coupled receptors and receptor tyrosine kinases, allowing it to integrate diverse extracellular signals. In the context of oncology, PIK3CB is frequently the dominant PI3K isoform driving growth in PTEN-deficient tumors, such as certain prostate and breast cancers (Wee et al., PNAS, 2008). Consequently, p110β inhibitors are being developed as targeted therapies for both antithrombotic applications and the treatment of PTEN-null malignancies. These inhibitors aim to provide a wider therapeutic window by selectively targeting the isoform responsible for disease pathology while sparing others involved in normal physiology. Clinical development of these agents requires careful monitoring of metabolic and hematologic parameters due to the enzyme's role in insulin signaling and platelet function.

Other names

p110-betaPI3K-betaPI3KbetaPIK3C1Phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit beta isoform

Selective inhibition of the p110β catalytic subunit of Class IA phosphoinositide 3-kinase, preventing the phosphorylation of PIP2 to PIP3 and inhibiting downstream Akt signaling pathways.