SWATH-Proteomics of Ibrutinib's Action in Myeloid Leukemia Initiating Mutated G-CSFR Signaling.

PURPOSE: To evaluate cellular protein changes in response to treatment with an approved drug, ibrutinib, in cells expressing normal or mutated Granulocyte-Colony Stimulating Factor Receptor (G-CSFR). G-CSFR mutations are associated with some hematological malignancies. Previous studies showed the efficacy of ibrutinib (a Bruton's tyrosine kinase inhibitor) in mutated G-CSFR leukemia models but did not addressed broader signaling mechanisms. EXPERIMENTAL DESIGN: A label-free quantitative proteomics workflow to evaluate the cellular effects of ibrutinib treatment was established. This included 3 biological replicates of normal and mutated G-CSFR expressed in a mouse progenitor cell (32D cell line) with and without ibrutinib treatment. RESULTS: The proteomics dataset showed about 1,000 unique proteins quantified with nearly 400 significant changes (p value < 0.05), suggesting a highly dynamic network of cellular signaling in response to ibrutinib. Importantly, the dataset was very robust with coefficients of variation (CVs) for quantitation at 13.0-20.4% resulting in dramatic patterns of protein differences among the groups. CONCLUSIONS AND CLINICAL RELEVANCE: This robust data set is available for further mining, hypothesis generation, and testing. A detailed understanding of the restructuring of the proteomics signaling cascades by ibrutinib in leukemia biology will provide new avenues to explore its use for other related malignancies. This article is protected by copyright. All rights reserved.