Supplementary Data from Dasatinib Inhibits the Growth of Molecularly Heterogeneous Myeloid Leukemias (original) (raw)

Dasatinib Inhibits the Growth of Molecularly Heterogeneous Myeloid Leukemias

Clinical Cancer Research, 2010

Purpose-Dasatinib is a dual Src/Abl inhibitor, recently approved for Bcr-Abl+ leukemias with resistance or intolerance to prior therapy. Because Src kinases contribute to multiple blood cell functions by triggering a variety of signaling pathways, we hypothesized that their molecular targeting might lead to growth inhibition in acute myeloid leukemia (AML).

Data from Dasatinib Inhibits the Growth of Molecularly Heterogeneous Myeloid Leukemias

Purpose: Dasatinib is a dual Src/Abl inhibitor recently approved for Bcr-Abl+ leukemias with resistance or intolerance to prior therapy. Because Src kinases contribute to multiple blood cell functions by triggering a variety of signaling pathways, we hypothesized that their molecular targeting might lead to growth inhibition in acute myeloid leukemia (AML).Experimental Design: We studied growth factor–dependent and growth factor–independent leukemic cell lines, including three cell lines expressing mutants of receptor tyrosine kinases (Flt3 or c-Kit) as well as primary AML blasts for responsiveness to dasatinib.Results: Dasatinib resulted in the inhibition of Src family kinases in all cell lines and blast cells at ∼1 × 10−9 mol/L. It also inhibited mutant Flt3 or Kit tyrosine phosphorylation at ∼1 × 10−6 mol/L. Mo7e cells expressing the activating mutation (codon 816) of c-Kit were most sensitive to growth inhibition with a GI50 of 5 × 10−9 mol/L. Primary AML blast cells exhibited a...

Dasatinib Targets B-Lineage Cells but Does Not Provide an Effective Therapy for Myeloproliferative Disease in c-Cbl RING Finger Mutant Mice

PLoS ONE, 2014

This study aimed to determine whether the multi-kinase inhibitor dasatinib would provide an effective therapy for myeloproliferative diseases (MPDs) involving c-Cbl mutations. These mutations, which occur in the RING finger and linker domains, abolish the ability of c-Cbl to function as an E3 ubiquitin ligase and downregulate activated protein tyrosine kinases. Here we analyzed the effects of dasatinib in a c-Cbl RING finger mutant mouse that develops an MPD with a phenotype similar to the human MPDs. The mice are characterized by enhanced tyrosine kinase signaling resulting in an expansion of hematopoietic stem cells, multipotent progenitors and cells within the myeloid lineage. Since c-Cbl is a negative regulator of c-Kit and Src signaling we reasoned that dasatinib, which targets these kinases, would be an effective therapy. Furthermore, two recent studies showed dasatinib to be effective in inhibiting the in vitro growth of cells from leukemia patients with c-Cbl RING finger and linker domain mutations. Surprisingly we found that dasatinib did not provide an effective therapy for c-Cbl RING finger mutant mice since it did not suppress any of the hematopoietic lineages that promote MPD development. Thus we conclude that dasatinib may not be an appropriate therapy for leukemia patients with c-Cbl mutations. We did however find that dasatinib caused a marked reduction of pre-B cells and immature B cells which correlated with a loss of Src activity. This study is therefore the first to provide a detailed characterization of in vivo effects of dasatinib in a hematopoietic disorder that is driven by protein tyrosine kinases other than BCR-ABL.

In vivo, ex vivo and in vitro dasatinib activity in chronic lymphocytic leukemia

Oncology Letters, 2021

Dasatinib inhibits the breakpoint cluster region-Abelson murine leukemia 1 (BCR-ABL1) gene along with other kinases known to be overexpressed and abnormally active in patients with chronic lymphocytic leukemia (CLL). The current study used primary leukemic cells obtained from 53 patients with CLL that were treated with dasatinib. A 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT) assay and Annexin V staining was performed to assess the cytotoxic effects of dasatinib treatment. The XTT assay revealed that the median cytotoxicity of dasatinib was 8.30% (range, 0.00–77.89%). Due to high dispersion of dasatinib activity, patients were divided into sensitive (n=27; 50.94%; median cytotoxicity, 22.81%) and resistant groups (n=26; 49.06%; median cytotoxicity, 0.00%). A median cytotoxicity of 8.30% was selected as a cut off value. Using Annexin V staining and flow cytometry on exemplary sensitive and resistant CLL samples, it was revealed that 17.71 and 1.84% o...

Dasatinib in chronic myeloid leukemia: A limited Indian experience

Asia-Pacific Journal of Clinical Oncology, 2012

To report our experience of the use of dasatinib in various phases of chronic myeloid leukemia (CML). Methods: Ten patients in various phases of CML, not responding to imatinib and started on dasatinib, were included and analyzed. The baseline characteristics of the patients and their salient features including the duration and response to initial therapy as well as to dasatinib, were noted. Results: Before starting dasatinib three patients were in chronic phase of CML while seven others were in the progressive phase (accelerated and blast phase) of CML. Half the patients developed transient grade 3 and 4 toxicities to dasatinib. Overall, the tolerability of the drug in all 10 patients was acceptable and none discontinued treatment. Three patients died due to progressive disease while the remaining seven are continuing the drug with the disease still under cytogenetic or hematological remission. Of the 10 patients, seven achieved complete hematological response and two of the accelerated phase/blast crisis patients achieved complete cytogenetic response. Overall, dasatinib was able to control disease for a median of 20.6 months.