Phosphatidylinositol 3-kinase and mammalian target of rapamycin (PI3K and mTOR) (PI3K and mTOR)

Phosphatidylinositol 3-kinase (PI3K) and mammalian target of rapamycin (mTOR) are key protein kinases in intracellular signal transduction, regulating critical cellular processes including growth, survival, proliferation, metabolism, autophagy, and cell cycle progression[4][5][6][7][9]. PI3Ks, a family of lipid kinases, phosphorylate phosphatidylinositol lipids to generate secondary messengers that activate downstream kinases such as AKT. mTOR is a serine/threonine kinase that forms two complexes (mTORC1 and mTORC2) and acts downstream of PI3K signaling to regulate protein synthesis and cell metabolism[3]. Dysregulation of this pathway is a hallmark of many cancers and has therapeutic implications, making both PI3K and mTOR primary targets for drug development in oncology and other diseases[2][4][5][7][8][9]. Because they are part of a tightly integrated pathway but exist as distinct molecular entities, structured information should generally treat PI3K and mTOR as separate therapeutic targets rather than a single entry.

Other names

PI3K (for Phosphatidylinositol 3-kinase)mTOR (for Mammalian target of rapamycin)FRAP1 (alternative name for mTOR)PI3 kinaseMechanistic target of rapamycinRapamycin-sensitive kinase

PI3K inhibitors: block phosphorylation of inositol lipids, downstream signaling attenuation mTOR inhibitors: inhibit mTOR kinase activity, block mTORC1/C2 signaling, reduce protein synthesis and cell growth Dual inhibitors: inhibit both PI3K and mTOR activities to achieve broader pathway blockade