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Drug resistance in glioblastoma

ABSTRACT: Combined model of in vitro and in vivo resistance to alkylating agents (BCNU and Temozolomide) in glioblastoma multiforme. Three matched pairs of surgical specimens from initial (DI, ME, LX) and repeat (DIR, MER, LXR) tumor resection were used to establish cell lines. Patients received BCNU chemotherapy between the two operations, which rendered the sublines from repeat surgery more resistant to BCNU than those from initial surgery. Each the pre-chemotherapeutic set and the post-chemotherapeutic set of cell lines was selected in vitro for resistance to either BCNU or Temozolomide. 9 in vitro selected sublines were established. Of those 4 (2 selected for BCNU [ME-BCNU, DI-BCNU] and 2 selected for Temozolomide [ME-TMZ, LX-TMZ) were generated from the parental/sensitive pre-chemotherapeutic set and 5 (2 selected for BCNU [DIR-BCNU, MER-BCNU] and 3 selected for Temozolomide [DIR-TMZ, MER-TMZ, LXR-TMZ) from the in vivo resistant post-chemotherapeutic set. The model included a total of 15 sublines. Genome-wide high-resolution gene copy number profiling was performed on each subline using 42,000-feature cDNA microarrays. Utilizing the same microarray platform genome-wide gene expression profiles were generated. Biostatistical tools were employed to identify signatures of resistance to alkylating agents both at the genetic as well as at the transcriptomic levels. Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. Series_type = Logical Set Keywords: other

ORGANISM(S): Homo sapiens

PROVIDER: GSE2221 | GEO | 2006/01/27

SECONDARY ACCESSION(S): PRJNA91473

REPOSITORIES: GEO

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