title: Pharmacogenomic approach for the identification of novel determinants of acquired resistance to oxaliplatin in colorectal cancer.
abstract: Oxaliplatin is a third-generation platinum agent used in colorectal cancer treatment. Oxaliplatin resistance acquisition is a complex process mainly based on alteration of genes and pathways involved in its mechanism of action. Therefore, our purpose was to perform a gene expression screening in an in vitro model to identify genes that could play a role in oxaliplatin resistance acquisition processes. Four colorectal cancer cell lines and their oxaliplatin-resistant derived sublines were compared. Microarray analysis was done using Human 19K Oligo Array Slides. RNA from cells were hybridized with a commercial RNA reference sample and labeled with both fluorochromes Cy3 and Cy5. Data were analyzed by hierarchical clustering method. Subsequently, quantitative real-time PCR (qRT-PCR) was used to corroborate microarray data, considering as positively validated those genes that showed significant differences in expression levels between groups and a correlation between microarray and qRT-PCR data. By microarray analysis, 32 candidate genes were identified. After validation process by qRT-PCR, the genes AKT1, CDK5, TRIP, GARP, RGS11, and UGCGL1 were positively validated. The 3 first genes proved to be involved in regulation of nuclear factor-kappabeta antiapoptotic transcription factor previously related to drug resistance, and the other 3 genes are novel finds. We have identified 6 genes related to oxaliplatin resistance acquisition. These findings are of paramount importance to understand these processes better and open new lines of study to elucidate the relevance of this pharmacogenomic approach into the clinic.
authors.affiliation: Medical Oncology Service, Institut Català Oncologia, Hospital Universitari Germans Trias i Pujol, Badalona 08916, Barcelona, Spain.
authors.forename: Anna
authors.initials: A
authors.lastname: Martinez-Cardús
authors.forename: Eva
authors.initials: E
authors.lastname: Martinez-Balibrea
authors.forename: Eva
authors.initials: E
authors.lastname: Bandrés
authors.forename: Raquel
authors.initials: R
authors.lastname: Malumbres
authors.forename: Alba
authors.initials: A
authors.lastname: Ginés
authors.forename: José Luís
authors.initials: JL
authors.lastname: Manzano
authors.forename: Miquel
authors.initials: M
authors.lastname: Taron
authors.forename: Jesús
authors.initials: J
authors.lastname: Garcia-Foncillas
authors.forename: Albert
authors.initials: A
authors.lastname: Abad
mesh_terms: D045744:Cell Line, Tumor; D002469:Cell Separation; D002470:Cell Survival / Q000187:drug effects; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology*; D019008:Drug Resistance, Neoplasm / Q000187:drug effects / Q000235:genetics*; D020869:Gene Expression Profiling; D006801:Humans; D009944:Organoplatinum Compounds / Q000494:pharmacology*; D000077150:Oxaliplatin; D010597:Pharmacogenetics; D012333:RNA, Messenger / Q000235:genetics
chemical_list: D009944:Organoplatinum Compounds; D012333:RNA, Messenger; D000077150:Oxaliplatin