Mammalian target of sirolimus (mTOR) is a serine / threonine protein kinase,it widely expresses in cells and has been indicated as a reliable target for tumor treatment.Everolimus,a rapamycin derivative is an oral mTOR inhibitor.It improves the drug properties of rapamycin,and inhibits mammalian tumor cell growth and differentiation.In March 2009,everolimus was approved for the treatment of advanced renal cell carcinoma by US Food and Drug Addministration.At present,some clinical research advances on antitumor efficacy of everolimus in breast cancer,lung cancer,gastric cancer and other tumors have been proceeded.