Project description:APE1 regulates a vast majority of genes by acting as a transcriptional co-activator or as a co-repressor. It is overexpressed in diverse cancer tissues and is associated with their drug resistance. It is essential for cell proliferation. APE1 is post-translationally acetylated by HAT p300 at its N-terminal Lys 6 and 7 residues. We examined APE1 and its acetylation-dependent gene expression profile of lung cancer cells which would contribute to sustained proliferation of lung cancer cells. We used microarry based gene expression profile analysis using affymetrix HG-U133-Plus 2 array. For differential expression testing, Linear Models for MicroArray (Limma) was used to fit linear models for analyzing designed experiments and the assessment of overall gene expression and contrast analysis comparing the experimental groups
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:Lung cancer is the leading cause of cancer death worldwide. The lack of specific and sensitive methods for early diagnosis as well as inadequate targeted therapies contribute to poor outcomes. A growing body of evidences suggests different roles of microRNAs including development and progression of lung cancer. The overexpression of the DNA repair protein apurinic/apyrimidinic endonuclease 1 (APE1) is an important cause of poor chemotherapeutic and its expression is able to predict the progression-free and overall survival in patients receiving platinum-containing chemotherapy. Recently, we have demonstrated APE1 involvement in miRNA biogenesis related to cancer progression. In this article, we report the identification of miRNAs that are modulated in lung cancer cells upon APE1 silencing. We defined a miRNA signature consisting of the 13 miRNAs, which strongly correlates with APE1 expression in lung cancer: miR-1246, miR-4488, miR-24, miR-183, miR-660, miR-130b, miR-543, miR-200c, miR-376c, miR-218, miR-146a, miR-92b and miR-33a. Gene ontology annotation and pathway analysis of the miRNA signature revealed its biological significance in cancer proliferation and survival. Among the miRNAs downregulated by APE1 is miRNA-33a-5p which targets Dicer, a major miRNA biogenesis gene whose expression is found to be downregulated in several tumours. We here validated Dicer as a direct functional target of miR-33a and profiled miR-33a, DICER and APE1 expression in clinical samples. Our findings suggest that APE1 may promote lung cancer progression through modulation of Dicer expression via miR-33a regulation. Our findings reveal new mechanistic insight into how APE1 functions in tumor biology.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.