title: Modulation of IMPDH2, survivin, topoisomerase I and vimentin increases sensitivity to methotrexate in HT29 human colon cancer cells.
abstract: We determined differentially expressed genes in HT29 human colon cancer cells, both after short treatment with methotrexate (MTX) and after the resistance to MTX had been established. Screening was performed using Atlas Human Cancer 1.2K cDNA arrays. The analysis was carried out using Atlas image 2.01 and genespring 6.1 software. Among the differentially expressed genes we chose for further validation were inosine monophosphate dehydrogenase type II (IMPDH2), inosine monophosphate cyclohydrolase and survivin as up-regulated genes, and topoisomerase I (TOP1) and vimentin as down-regulated genes. Changes in mRNA levels were validated by quantitative RT-PCR. Additionally, functional analyses were performed inhibiting the products of the selected genes or altering their expression to test if these genes could serve as targets to modify MTX cytotoxicity. Inhibition of IMPDH or TOP1 activity, antisense treatment against survivin, or overexpression of vimentin, sensitized resistant HT29 cells to MTX. Therefore, these proteins could constitute targets to develop modulators in MTX chemotherapy.
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Pharmacy, University of Barcelona, Spain.
authors.forename: Silvia
authors.initials: S
authors.lastname: Peñuelas
authors.forename: Véronique
authors.initials: V
authors.lastname: Noé
authors.forename: Carlos J
authors.initials: CJ
authors.lastname: Ciudad
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology*; D001483:Base Sequence; D015153:Blotting, Western; D003110:Colonic Neoplasms / Q000201:enzymology / Q000235:genetics / Q000473:pathology*; D017931:DNA Primers; D004264:DNA Topoisomerases, Type I / Q000235:genetics*; D018076:DNA, Complementary; D019073:HT29 Cells; D006801:Humans; D007168:IMP Dehydrogenase / Q000235:genetics*; D051034:Inhibitor of Apoptosis Proteins; D008727:Methotrexate / Q000494:pharmacology*; D008869:Microtubule-Associated Proteins / Q000235:genetics*; D009363:Neoplasm Proteins; D020411:Oligonucleotide Array Sequence Analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000077022:Survivin; D014746:Vimentin / Q000235:genetics*
chemical_list: D000964:Antimetabolites, Antineoplastic; C107489:BIRC5 protein, human; D017931:DNA Primers; D018076:DNA, Complementary; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D000077022:Survivin; D014746:Vimentin; D007168:IMP Dehydrogenase; D004264:DNA Topoisomerases, Type I; D008727:Methotrexate