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Array CGH on gemcitabine resistant tumor

ABSTRACT: Biological material: One solid mouse tumor "Colon 26A" was routinely maintained by successive transplantation. A subset of mice with this tumor was treated at the maximum tolerable dosage of Gemcitabine and successively transplanted 5 times and similarly treated. The last passage was completly resistant and designated, "Colon 26G". Oligo array CGH microarray: DNA from tumor and normal liver samples were isolated using the Wizard Genomic DNA purification kit according to the manufactures protocol (Promega Benelux BV, Leiden, NL). Labeling and hybridization procedures for the oligo array CGH were performed as previously described (Carvalho et al, 2004, J. Clin. Pathol., 57:644-649) with the following modifications: a mouse oligo library version 2.0 (Compugen/Sigma-Aldrich Chemie B.V., Zwijndrecht, NL) containing 21,997 oligonucleotides (65bp) representing 21,587 exon regions on all chromosomes were spotted on the arrays. Prehybridisation was omitted and Cot-1 concentrations during the hybridization were reduced to 100 Âµg. Hybridizations were done using a Hybstation12 (Perkin-Elmer, Zaventem, BE). CGH arrays were scanned using a laser scanner (Agilent Technologies, Amstelveen, NL) and analyzed using Bluefuse Software v.2.0 (Bluegnome Ltd, Cambridge, UK). Images show fused values; values with confidence higher then 0.35 with the overall Cy3 and Cy5 channels normalized to a log2ratio of 0. Tumor 26G was hybridized twice and Bluefuse confidence based average values are given. No further normalizations were performed. For interpretation and visualization purposes,smoothing was performed by version 2 of aCGH smooth, with Î» set to 2.0.

ORGANISM(S): Mus musculus

SUBMITTER: Paul van den IJssel

PROVIDER: E-GEOD-2373 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

Expression microarray analysis and oligo array comparative genomic hybridization of acquired gemcitabine resistance in mouse colon reveals selection for chromosomal aberrations.

van de Wiel Mark A MA Costa Jose L JL Smid Kees K Oudejans Cees B M CB Bergman Andries M AM Meijer Gerrit A GA Peters Godefridus J GJ Ylstra Bauke B

Cancer research 20051101 22

Gemcitabine is a commonly used therapy for many solid tumors. Acquired resistance to this nucleoside analogue, however, diminishes the long-term effectiveness in a majority of patients. To better define the molecular background of gemcitabine resistance, a mouse colon tumor was selected during successive rounds of transplantation with continued treatment of gemcitabine. Expression microarray analysis was applied to determine which genes are consistently and highly overexpressed or underexpressed ...[more]

PMID: 16288008

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Dataset Information

Array CGH on gemcitabine resistant tumor

Publications

Expression microarray analysis and oligo array comparative genomic hybridization of acquired gemcitabine resistance in mouse colon reveals selection for chromosomal aberrations.

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