Metabolomics,Unknown,Transcriptomics,Genomics,Proteomics

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DNA copy numbers of malignant glioma in culture

ABSTRACT: Therapeutic screening of potential anticancer agents relies on representative cancer models. In vitro cell culture models have been long questioned to be representative for human malignant glioma. Therefore, in the present study genomic profiles of both short-term (2 weeks; n=8) and long-term (6 and 12 weeks; n=3) primary cell cultures and spheroid cultures were compared with their parental malignant gliomas. Cancer genomic profiles were obtained by 6400 BAC array comparative genomic hybridization. In 7 out of 8 short-term primary cell cultures, the genomic profiles clustered further from their parental tumors than the spheroid cultures. In 4 out of 8 samples, the changes were substantial and included chromosomal regions associated with prognosis and therapeutic response. The average correlation coefficients between parental tumor profiles and spheroid profiles was 0.89 (range: 0.79 to 0.97), whereas those between parental tumors and cell cultures was 0.62 (range: 0.10 to 0.96). In 2 out of 3 primary cell cultures progressive genetic changes appeared at 6 and 12 weeks after initial preservation, whereas the spheroid cultures were genetically stable throughout. It is concluded that the cancer genomic profile of primary cell cultures from malignant glioma is inconsistent with the parental tumorâs profile already after 2 weeks with subsequent progressive genetic changes. Because malignant glioma spheroids are genetically stable, biological characteristics of the parental tumor are better reflected. This indicates that the spheroid model is better for therapeutic screening. Keywords: comparative genomic hybridization Two in vitro culture models (primary cell culture and organotypic spheroid culture) and their parental tumor were compared in whole-genome DNA copy number profile. Malignant glioma surgical specimens from 8 patients were divided in parental tumor (T), primary cell culture (C) and organotypic spheroid culture (S). After 2 weeks, genomic DNA was extracted from culture harvests. For 3 of 8 surgical specimens (patient 55, 58, 60) cultures were extended to 6 and 12 weeks to determine DNA copy number changes in time. Primary cell culture harvests at 2, 6 and 12 weeks were named C1, C2, C3 and organotypic spheroid cultures harvests at 2, 6 and 12 weeks were named S1, S2, S3.

ORGANISM(S): Homo sapiens

SUBMITTER: Philip De Witt Hamer

PROVIDER: E-GEOD-6042 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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DNA copy numbers of malignant glioma in culture

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