Phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit beta (PIK3CB) (PIK3CB)

Phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit beta (PIK3CB), also known as p110β, is an enzyme that plays a pivotal role in the PI3K/AKT/mTOR signaling pathway by converting PIP2 to the second messenger PIP3 (UniProt P42338). It is a Class IA PI3K isoform uniquely regulated by both receptor tyrosine kinases (RTKs) and G protein-coupled receptors (GPCRs), distinguishing it from the p110α isoform (PubMed: 18418336). In many cancers, particularly those with PTEN deficiency, p110β becomes the dominant driver of oncogenic signaling, making it a high-priority therapeutic target (PubMed: 18724359). Beyond its role in oncology, p110β is essential for the activation and stable aggregation of platelets, which has led to its investigation as a target for antithrombotic therapy (PubMed: 15937473). Current drug development efforts focus on selective p110β inhibitors to treat PTEN-null tumors while minimizing the metabolic side effects, such as severe hyperglycemia, often associated with pan-PI3K or p110α-specific inhibition (PubMed: 28455345).

Other names

p110-betaPI3K-betaPI3KbetaP110BETAPIK3C1

Competitive inhibition of the ATP-binding site of the p110 beta catalytic subunit, preventing the conversion of phosphatidylinositol 4,5-bisphosphate (PIP2) to phosphatidylinositol 3,4,5-trisphosphate (PIP3), thereby dampening the AKT signaling pathway.