Definition

An orally bioavailable, ATP-competitive inhibitor of raptor-mammalian target of rapamycin (mTOR) complex 1 (mTOR complex 1; mTORC1; TOR complex 1; TORC1) and rictor-mTOR (mTOR complex 2; mTORC2; TOR complex 2; TORC2), with potential antineoplastic activity. Upon oral administration, mTORC1/mTORC2 inhibitor XL388 targets, selectively binds to and inhibits both mTORC1 and mTORC2, which may result in apoptosis and a decrease in proliferation in mTORC1/2-expressing tumor cells. mTOR is a serine/threonine kinase that is upregulated in some tumors; it plays an important role in the PI3K/Akt/mTOR signaling pathway which is often deregulated in cancer cells.