Abstract P2-19-05: Inhibitor Screening Utilizing Human Kinase Multiplex Arrays

Protein kinase pathways show dysregulation in cancer, usually displaying increased activation. Kinases are typically influenced by extracellular signals, and many kinases are now considered to be therapeutic targets. Upon phosphorylation, kinases regulate signaling pathways that effect cellular processes. Individual cell lines, including cancer cells, express different kinase activation patterns. Previously, we have shown the phospho-tyrosine kinase profile of MDA-MB-453 cells, most notably the Erb family of Receptor Tyrosine Kinases, to be hyperactivated in this breast cancer cell line. Using a new kinase multiplex plate-based array, we have seen similar activation of multiple intracellular kinases, such as Akt and Erk. As a result, the MDA-MB-453 cells were selected for treatment with a kinase inhibitor library (Enzo, Catalog # BML-2832-0100). While several of the inhibitors block kinase activation, other inhibitors block proteins that are upstream from their kinase target. After incubation with the inhibitor library, a multiplex kinase array was utilized to screen the effects of the inhibitors on the MDA-MB-453 cells. In contrast with MCF-7 cells, MDA-MB-453 breast cancer cells showed a basal hyperactivation of the Akt and GSK-3β kinases. The activation of Akt could be selectively inhibited by SB-203580, SB-202190, ML-7, and BML-265 inhibitors. The results obtained in the multiplex assay were verified by singleplex ELISA for Akt. Hence, the data collected with the multiplex assay provide a rapid analysis of the inhibitors’ effects on defined signaling pathways. This allows for a faster identification of kinase inhibitors that may affect cancer cells. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-19-05.