Phosphatidylinositol 4,5-bisphosphate 3-kinase (PI3K) (PI3K)

Phosphatidylinositol 4,5-bisphosphate 3-kinase (PI3K) is a critical enzyme family involved in regulating key cellular processes including growth, proliferation, and survival (UniProt P42336). It functions by phosphorylating phosphatidylinositol 4,5-bisphosphate (PIP2) to generate phosphatidylinositol 3,4,5-trisphosphate (PIP3), which acts as a second messenger to activate the AKT/mTOR signaling pathway (PubMed: 29045733). Dysregulation or overactivation of PI3K signaling is a hallmark of various malignancies, particularly B-cell lymphomas and solid tumors (FDA Label: Aliqopa). Copanlisib is a potent pan-Class I PI3K inhibitor with primary activity against the alpha (PI3K-alpha) and delta (PI3K-delta) isoforms (PubChem CID 46173634). By blocking these enzymes, Copanlisib inhibits downstream signaling, induces apoptosis, and reduces the proliferation of malignant B-cells (PubMed: 30215161). Clinical monitoring of systemic exposure is important because the drug's effect on PI3K-alpha can lead to transient hyperglycemia and hypertension, reflecting the enzyme's role in systemic glucose metabolism and vascular homeostasis (FDA Label: Aliqopa).

Other names

Phosphoinositide 3-kinasePI 3-kinasePI3-kinasePhosphatidylinositol-4,5-bisphosphate 3-kinasePIK3CAPIK3CD

Inhibition of the catalytic activity of Class I PI3K isoforms, specifically alpha and delta, preventing the phosphorylation of PIP2 to PIP3 and subsequent activation of the AKT/mTOR signaling pathway.