A FLT3-targeted tyrosine kinase inhibitor is cytotoxic to leukemia cells in vitro and in vivo |
| |
Authors: | Levis Mark Allebach Jeffrey Tse Kam-Fai Zheng Rui Baldwin Brenda R Smith B Douglas Jones-Bolin Susan Ruggeri Bruce Dionne Craig Small Donald |
| |
Affiliation: | Johns Hopkins University School of Medicine, Department of Oncology, Baltimore, MD 21231-1000, USA. |
| |
Abstract: | Constitutively activating internal tandem duplication (ITD) and point mutations of the receptor tyrosine kinase FLT3 are present in up to 41% of patients with acute myeloid leukemia (AML). These FLT3/ITD mutations are likely to be important because their presence is associated with a poor prognosis. Both types of mutations appear to activate the tyrosine kinase activity of FLT3. We describe here the identification and characterization of the indolocarbazole derivative CEP-701 as a FLT3 inhibitor. This drug potently and selectively inhibits autophosphorylation of wild-type and constitutively activated mutant FLT3 in vitro in FLT3/ITD-transfected cells and in human FLT3-expressing myeloid leukemia-derived cell lines. We demonstrate that CEP-701 induces a cytotoxic effect on cells in a dose-responsive fashion that parallels the inhibition of FLT3. STAT5 and ERK1/2, downstream targets of FLT3 in the signaling pathway, are inhibited in response to FLT3 inhibition. In primary leukemia blasts from AML patients harboring FLT3/ITD mutations, FLT3 is also inhibited, with an associated cytotoxic response. Finally, using a mouse model of FLT3/ITD leukemia, we demonstrate that the drug inhibits FLT3 phosphorylation in vivo and prolongs survival. These findings form the basis for a planned clinical trial of CEP-701 in patients with AML harboring FLT3- activating mutations. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
| 点击此处可从《Blood》浏览原始摘要信息 |
|
点击此处可从《Blood》下载全文 |
|