Supplementary methods and Figures from The Dual Syk/JAK Inhibitor Cerdulatinib Antagonizes B-cell Receptor and Microenvironmental Signaling in Chronic Lymphocytic Leukemia
Supplementary methods and Figures Supplementary Figure 1. Effect of cerdulatinib on Immobilised anti-IgM mediated signaling Supplementary Figure 2. Effect of cerdulatinib on soluble anti-IgM mediated signaling Supplementary Figure 3. Effect of cerdulatinib on Immobilised anti-IgD mediated signaling Supplementary Figure 4. Effect of cerdulatinib on soluble anti-IgD mediated signaling Supplementary Figure 5. Effect of cerdulatinib on anti-IgM induced calcium flux and IL-4 induced surface marker expression Supplementary Figure 6. Representative phosflow plots Supplementary Figure 7. Cerdulatinib overcomes the protective effect of BCR-stimulation and IL- 4/CD40L. Supplementary Figure 8. Mcl-1 and Bcl-XL but not Bcl-2 are downregulated by cerdulatinib Supplementary Figure 9. Effect of cerdulatinib on MCL-1 and BCL-XL mRNA expression
Funding
Leukemia & Lymphoma Society Scholar Award in Clinical Research
MD Anderson's Moon Shot Program
MD Anderson Cancer Center
History
ARTICLE ABSTRACT
Purpose: B-cell receptor (BCR)–associated kinase inhibitors, such as ibrutinib, have revolutionized the treatment of chronic lymphocytic leukemia (CLL). However, these agents are not curative, and resistance is already emerging in a proportion of patients. IL4, expressed in CLL lymph nodes, can augment BCR signaling and reduce the effectiveness of BCR kinase inhibitors. Therefore, simultaneous targeting of the IL4- and BCR signaling pathways by cerdulatinib, a novel dual Syk/JAK inhibitor currently in clinical trials (NCT01994382), may improve treatment responses in patients.Experimental Design: PBMCs from patients with CLL were treated in vitro with cerdulatinib alone or in combination with venetoclax. Cell death, chemokine, and cell signaling assay were performed and analyzed by flow cytometry, immunoblotting, q-PCR, and ELISA as indicated.Results: At concentrations achievable in patients, cerdulatinib inhibited BCR- and IL4-induced downstream signaling in CLL cells using multiple readouts and prevented anti-IgM- and nurse-like cell (NLC)–mediated CCL3/CCL4 production. Cerdulatinib induced apoptosis of CLL cells, in a time- and concentration-dependent manner, and particularly in IGHV-unmutated samples with greater BCR signaling capacity and response to IL4, or samples expressing higher levels of sIgM, CD49d+, or ZAP70+. Cerdulatinib overcame anti-IgM, IL4/CD40L, or NLC-mediated protection by preventing upregulation of MCL-1 and BCL-XL; however, BCL-2 expression was unaffected. Furthermore, in samples treated with IL4/CD40L, cerdulatinib synergized with venetoclax in vitro to induce greater apoptosis than either drug alone.Conclusions: Cerdulatinib is a promising therapeutic for the treatment of CLL either alone or in combination with venetoclax, with the potential to target critical survival pathways in this currently incurable disease. Clin Cancer Res; 23(9); 2313–24. ©2016 AACR.Usage metrics
