mammalian target of rapamycin (muh-MA-lee-un TAR-get … RA-puh-MY-sin)
A protein that helps control several cell functions, including cell division and survival, and binds to rapamycin and other drugs. Mammalian target of rapamycin may be more active in some types of cancer cells than it is in normal cells. Blocking mammalian target of rapamycin may cause the cancer cells to die. It is a type of serine/threonine protein kinase. Also called mTOR.