Project description:41 lung adenocarcinoma from never-smokers hybridized on Illumina SNP arrays on 13 HumanCNV370-Quadv3 chips. High-resolution array comparative genomic hybridization analysis of lung adenocarcinoma in 41 never smokers for identification of new minimal common regions (MCR) of gain or loss. The SNP array analysis validated copy-number aberrations and revealed that RB1 and WRN were altered by recurrent copy-neutral loss of heterozygosity.The present study has uncovered new aberrations containing cancer genes. The oncogene FUS is a candidate gene in the 16p region that is frequently gained in never smokers. Multiple genetic pathways defined by gains of MYC, deletions of RB1 and WRN or gains on 7p and 7q are involved in lung adenocarcinoma in never smokers. A 'Cartes d'Identite des Tumeurs' (CIT) project from the French National League Against Cancer (http://cit.ligue-cancer.net) 41 samples hybridized on Illumina SNP arrays. Submitter : Fabien PETEL petelf@ligue-cancer.net . Project leader : Pr Pierre FOURET pierre.fouret@psl.aphp.fr
Project description:We demonstrate that miR-708 is one of the most highly overexpressed miRNAs in non-small cell lung cancer. High level of miR-708 in tumor is also associated with a reduced overall survival in lung adenocarcinomas from never smokers. Functionally, miR-708 overexpression increases the proliferation, migration, and invasion in cultured cells and down regulates TMEM88, a negative regulator of Wnt signaling. Jointly, our results support an oncogenic role of miR-708 by activating Wnt signaling pathway to promote lung cancer progression. We performed miRNA expression profiling in matched lung adenocarcinoma and uninvolved lung using 47 pairs from formalin-fixed, paraffin-embedded [FFPE] tissues from never smokers. We performed miRNA expression profiling in matched lung adenocarcinoma and uninvolved lung using 56 pairs of fresh-frozen [FF] samples from never smokers.
Project description:Approximately 15% of lung cancer cases are not associated with smoking and show molecular and clinical characteristics distinct from those in smokers. Epidermal growth factor receptor (EGFR) gene mutations, which are correlated with sensitivity to EGFR-tyrosine kinase inhibitors (EGFR-TKIs), are more frequent in never-smoker lung cancers. In this study, microRNA (miRNA) expression profiling of 28 never-smoker lung cancer cases identified aberrantly expressed miRNAs, which were much fewer than in lung cancers of smokers and included miRNAs previously identified (e.g., upregulated miR-21) and unidentified (e.g., downregulated miR-138) in those smoker cases. The changes in expression of some of these miRNAs were more remarkable in cases with EGFR mutations than in those without: the most upregulated miRNA, miR-21, was more abundant in cancers with EGFR mutation. A significant correlation between phosphorylated-EGFR (p-EGFR) and miR-21 levels in lung carcinoma cell lines and the suppression of miR-21 by an EGFR-TKI, AG1478, suggested that the EGFR signaling pathway positively regulated miR-21 expression. In a never-smoker-derived lung adenocarcinoma cell line H3255 with mutant EGFR and high levels of p-EGFR and miR-21, antisense inhibition of miR-21 enhanced AG1478-induced apoptosis. In a never-smoker-derived adenocarcinoma cell line H441 with wild-type EGFR, the antisense miR-21 not only showed the additive effect with AG1478 but also induced apoptosis by itself. These results suggest that aberrantly increased expression of miR-21, which is further enhanced by the activated EGFR signaling pathway, plays a critical role in lung carcinogenesis in never-smokers and is a potential therapeutic target in both EGFR mutant and wild-type cases. Twenty-eight pairs of lung cancer tissues and corresponding noncancerous lung tissues were obtained from never-smokers who had undergone surgical resection from 2000 to 2004 at the University of Maryland Medical Center (n=15), Mayo Clinic (n=7) in United States and Hamamatsu University School of Medicine (n=6) in Japan.