Abstract 3744: High-throughput in vitro screening of glioma stem cell lines: Evaluation of over 350 tyrosine kinase inhibitors

Abstract

Abstract Despite the availability of hundreds of drugs, there is little data on the efficacy of these agents in the extremely heterogeneous populations of tumor cells observed in glioblastoma. A high-throughput compound-screening assay was used to identify drug sensitivities in a panel of glioma stem cell (GSC) lines to 350 tyrosine kinase inhibitors (GSK PKIS1) with varying cellular targets and mechanisms of kinase inhibition. Twelve glioma stem cell lines, which are representative of the classic TCGA molecular subtypes, were screened. Cell lines were screened in 384-well plates at a density of 1000 cells/well with drug concentrations of either 5 or 0.5 µM. Cell viability measurements were taken using Cell-Titer Glo five days after drug treatment and compared to control wells to calculate percentage inhibition. Compounds were defined as highly active (>90 % inhibition at 5µM; > 50% inhibition at 0.5µM), moderately active (>70% inhibition at 5µM; >30% inhibition at 0.5µM), or weakly active (>50% inhibition at 5µM; >15% inhibition at 0.5µM.) We identified three compounds that were highly active against eleven cell lines, three more compounds that were highly effective against at least seven cell lines, and seven additional compounds that were highly effective against at least four cell lines. The compounds in the screen were further analyzed by testing their inhibition efficacy against 220 kinases. A separate set of compounds containing molecularly targeted agents to TGF-beta, STAT3, PI3K and Notch were used for comparison of drug efficacy. Ongoing experiments are being performed to fully characterize the molecular phenotypes of the different GSC's by analyzing RNAseq, miRNA, the whole exome, the proteome, DNA methylation, and copy number variation. Integrating this information with the kinase and growth inhibition data will allow us to have a complete picture of the underlying mechanisms which drive resistance/sensitivity in GSC's. After determining which kinases are the most effective targets for the treatment of glioblastoma, promising compounds will be validated in intracranial in vivo xenograft models. Citation Format: Craig Thomas, Ji Liang, Yuji Piao, Nghi Nguyen, Erik Sulman, Clifford Stephan, Alfred Yung, John F. de Groot. High-throughput in vitro screening of glioma stem cell lines: Evaluation of over 350 tyrosine kinase inhibitors. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3744. doi:10.1158/1538-7445.AM2014-3744