Preclinical evaluation of the dual specific Src/Abl kinase inhibitor AZD0530 in lung cancer

• Published in: Journal of clinical oncology Vol. 24; no. 18_suppl; p. 13108
• Main Authors: Gautschi, O., Purnell, P., Evans, C. P., Yang, J. C., Holland, W. S., Bold, R. J., Virudachalam, S., Lara, P. N., Gandara, D. R., Gumerlock, P. H.
• Format: Journal Article
• Language: English; Japanese
• Published: 20.06.2006
• ISSN: 0732-183X; 1527-7755
• DOI: 10.1200/jco.2006.24.18_suppl.13108

Abstract only 13108 Background: AZD0530 is a highly selective, orally available, dual specific Src/Abl kinase inhibitor in clinical development. We tested this agent in multiple lung cancer cell lines in vitro. We hypothesized that activity of AZD0530 may depend on the level of activated (pY416-)Src, and that Src inhibition may decrease Bcl-xL protein levels and lower the barrier to apoptosis. Methods: NSCLC (A549, Calu-1, Calu-6) and SCLC (H69, H526) cells were incubated with 0.001–100 μM AZD0530 for 1–72hrs. Proliferation (MTT), DNA-content (flow cytometry), and protein levels of Src, pY416-Src, PARP, and Bcl-xL (Western blotting) were assessed. Results: Basal pY416-Src was detectable in most cell lines except H526. AZD0530 decreased pY416-Src levels at submicromolar concentrations in pY416-Src positive cells. In A549, Calu-1 and Calu-6, AZD0530 blocked cell growth in a time- and dose-dependent way (IC50 = 7–25 μM) by arrest in G1, retaining a cytostatic effect at submicromolar concentrations in A549 and Calu-1. AZD0530 induced apoptosis in 10–22% of these cells at micromolar concentrations, accompanied by a decrease of Bcl-xL protein in A549 and Calu-1. In H69 and H526, growth inhibition by AZD0530 was limited (IC50 >100 μM). Conclusions: 1) AZD0530 induced apoptosis at micromolar concentrations, and inhibited cell growth at micromolar to submicromolar concentrations in some cell lines. 2) pY416-Src is a potential marker for drug responsiveness, but other factors should also be tested. 3) Decrease of Bcl-xL by AZD0530 may render cancer cells more sensitive to chemotherapy. These data suggest that Src kinase inhibitors merit further testing in lung cancer, both alone and in combination with other agents. (Support: Swiss National Science Foundation, Swiss Cancer League, AstraZeneca). [Table: see text]