Identification of Bruton's tyrosine kinase as a therapeutic target in acute myeloid leukemia

Rushworth, SA, Murray, MY, Zaitseva, L, Bowles, KM and MacEwan, David ORCID: 0000-0002-2879-0935 (2014) Identification of Bruton's tyrosine kinase as a therapeutic target in acute myeloid leukemia. Blood, 123 (8). pp. 1229-1238.

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Abstract

Bruton’s tyrosine kinase (BTK) is a cytoplasmic protein found in all hematopoietic cell lineages except for T cells. BTK mediates signaling downstream of a number of receptors. Pharmacologic targeting of BTK using ibrutinib (previously PCI-32765) has recently shown encouraging clinical activity in a range of lymphoid malignancies. This study reports for the first time that ibrutinib inhibits blast proliferation from human acute myeloid leukemia (AML) and that treatment with ibrutinib significantly augmented cytotoxic activities of standard AML chemotherapy cytarabine or daunorubicin. Here we describe that BTK is constitutively phosphorylated in the majority of AML samples tested, with BTK phosphorylation correlating highly with the cell’s cytotoxic sensitivity toward ibrutinib. BTK-targeted RNAi knockdown reduced colony-forming capacity of primary AML blasts and proliferation of AML cell lines. We showed that ibrutinib binds at nanomolar range to BTK. Furthermore, we showed ibrutinib’s antiproliferative effects in AML are mediated via an inhibitory effect on downstream nuclear factor-κB survival pathways. Moreover, ibrutinib inhibited AML cell adhesion to bone marrow stroma. Furthermore, these effects of ibrutinib in AML were seen at comparable concentrations efficacious in chronic lymphocytic leukemia. These results provide a biological rationale for clinical evaluation of BTK inhibition in AML patients.

Item Type:	Article
Uncontrolled Keywords:	Myeloid Neoplasia, blast cells, ibrutinib, leukemia, myelocytic, acute, protein, tyrosine kinase, cell lines, cd34 anitgens, cell adhesion
Subjects:	?? RM ??
Depositing User:	Symplectic Admin
Date Deposited:	05 Dec 2014 14:52
Last Modified:	15 Dec 2022 12:31
DOI:	10.1182/blood-2013-06-511154
Related URLs:	Author Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/2003000