Conventional protein kinase C (cPKC) (cPKC)

Conventional protein kinase C (cPKC) isoforms, comprising alpha (PKC-α), beta (PKC-βI and PKC-βII), and gamma (PKC-γ), are a subfamily of serine/threonine kinases that require calcium and diacylglycerol (DAG) for activation [UniProt P17252, P05771, P05129]. These enzymes are critical mediators of signal transduction pathways that regulate essential cellular processes such as growth, differentiation, apoptosis, and platelet activation [PubMed: 26775738]. Dysregulation of cPKC isoforms is implicated in various diseases; for instance, PKC-β is a key driver in B-cell malignancies and diabetic microvascular complications, while PKC-α is often overexpressed in solid tumors [PubMed: 16170173, 23430114]. Pharmacological targeting of cPKCs has led to the development of several small-molecule inhibitors, such as midostaurin, which is FDA-approved for myeloid leukemia, and ruboxistaurin, which has been investigated for diabetic retinopathy [PubChem CID 9829523, 9812749]. Despite their therapeutic potential, the high structural homology between PKC isoforms presents a significant challenge for achieving selectivity, often resulting in off-target effects and dose-limiting toxicities in clinical settings [PubMed: 21814164].

Other names

Classical protein kinase CProtein kinase C alphaProtein kinase C betaProtein kinase C gammaPRKCAPRKCBPRKCGPKC-alphaPKC-betaPKC-gamma

ATP-competitive inhibition of the catalytic kinase domain; modulation of the C1 regulatory domain (for activators/downregulators like bryostatin).