Abstract 5577: Global analysis of protein kinase activity during hematopoietic differentiation

Abstract Cell proliferation and differentiation are highly regulated processes, and the deregulation of these processes can lead to a number of diseases including cancer. Protein kinases are key regulators of cell proliferation and differentiation, and consequently, potential targets for a number of oncology indications. A detailed understanding of the changes in kinase activity/expression during cell proliferation and differentiation may be one of the keys to the identification of novel biomarkers and targets for the diagnosis and treatment of these diseases. The HL-60 cell line is promyeloblastic, and protocols for the differentiation of these cells into either macrophages by 12-O-tetradecanoylphorbol-13-acetate (PMA), or granulocytes by retinoic acid (RA) are well-established. Importantly, HL-60 cell differentiation is a model system for the treatment of myelocytic leukemia, and identifying the mechanisms that induce terminal differentiation of these cells may reveal effective targets for treatment of this disease. With this in mind, we evaluated the kinase activity and expression profiles of HL-60 cells throughout the differentiation process using desthiobiotin acyl phosphate ATP and ADP probes and liquid chromatography-mass spectrometry. Greater than 150 protein kinases in resting, RA, and PMA HL-60 cells were analyzed. Significant changes in activity/expression were seen for a number of protein kinases in both differentiation pathways. These changes in kinase activity were generally consistent with changes in protein expression levels, as determined by Western blot. In both RA and PMA-induced HL60 differentiation, the kinetics for the changes in activity of the kinases was determined, and the results suggest that there is a well-defined sequence during which these changes occur. In summary, using activity based protein profiling, we identified a subset of kinases whose activity changed significantly during RA and PMA-induced HL-60 differentiation. Importantly, this methodology is widely applicable to other cellular systems and disease models, and has applications in the identification of biomarkers and targets for the management of these diseases. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5577.