title: RagD gene expression and NRF2 mutations in lung squamous cell carcinomas.
abstract: RagD is a member of the small G protein family, which encodes a recently discovered activator of the mTOR pathway. In vitro, RagD plays an important role in the proliferation of NRF2 gene (NFE2L2) mutated cancer cells. We hypothesized that tumor RagD expression may be correlated with the mutation status of NRF2 in lung cancers. RagD mRNA levels were analyzed by quantitative real-time polymerase chain reaction (qPCR) in 90 surgically-treated lung squamous cell cancer cases, including 14 NRF2 mutation cases, and normalized by β-actin mRNA levels. Mean RagD/β-actin mRNA levels of lung squamous cell carcinoma patients did not differ with age (≤65 vs. >65), Brinkman index (<400 vs. ≥400) or gender. RagD/β-actin mRNA levels were significantly higher in stage III samples (3.204±3.623) compared to stage I samples (1.357±1.560) (P= 0.0039). In addition, higher RagD/β-actin mRNA levels were identified in NRF2 mutant samples (3.107±3.633) compared to wild-type samples (1.774±2.301) (P=0.074). These results suggest that RagD induction by NRF2 activation plays a role in the proliferation of lung squamous cell cancers.
authors.affiliation: Department of Oncology, Immunology and Surgery, Nagoya City University Graduate School of Medical Sciences, Nagoya, Aichi 467-8601,  Japan.
authors.forename: Hidefumi
authors.initials: H
authors.lastname: Sasaki
authors.forename: Masayuki
authors.initials: M
authors.lastname: Shitara
authors.forename: Keisuke
authors.initials: K
authors.lastname: Yokota
authors.forename: Yu
authors.initials: Y
authors.lastname: Hikosaka
authors.forename: Satoru
authors.initials: S
authors.lastname: Moriyama
authors.forename: Motoki
authors.initials: M
authors.lastname: Yano
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Fujii