Activation of mammalian target of rapamycin pathway confers adverse outcome in nonsmall cell lung carcinoma

Abstract

BACKGROUND: Dysregulation of the mammalian target of rapamycin (mTOR) pathway has been shown to contribute to tumorigenesis. This study explored protein expression profiles of mTOR pathway and the relationship with prognosis in patients with nonsmall cell lung carcinoma (NSCLC). METHODS: The protein expression profiles of mTOR/phosphorylated (p-)mTOR, phosphoinositide-dependent kinase 1 (PDK1)/p-PDK1, p-Akt1, and P70 ribosomal protein S6 kinase (P70S6K)/p-P70S6K were determined via immunohistochemical staining assay. The clinical prognostic values of both single and combined protein expression were investigated with univariate and multivariate survival analysis. RESULTS: Compared with normal lung tissues, the protein levels of mTOR/p-mTOR, p-Akt1 Ser473/Thr308, and P70S6K/p-P70S6K were higher (all P