Evaluation of the antitumor effects of BPR1J-340, a potent and selective FLT3 inhibitor, alone or in combination with an HDAC inhibitor, vorinostat, in AML cancer
- PLoS One. 2014 Jan 8;9(1):e83160. doi: 10.1371/journal.pone.0083160.
- 1. Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Zhunan, Taiwan.
- 2. Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, Zhunan, Taiwan ; Department of Biological Science and Technology, National Chiao Tung University, Hsinchu, Taiwan.
Overexpression or/and activating mutation of FLT3 kinase play a major driving role in the pathogenesis of acute myeloid leukemia (AML). Hence, pharmacologic inhibitors of FLT3 are of therapeutic potential for AML treatment. In this study, BPR1J-340 was identified as a novel potent FLT3 Inhibitor by biochemical kinase activity (IC50 approximately 25 nM) and cellular proliferation (GC50 approximately 5 nM) assays. BPR1J-340 inhibited the phosphorylation of FLT3 and STAT5 and triggered Apoptosis in FLT3-ITD(+) AML cells. The pharmacokinetic parameters of BPR1J-340 in rats were determined. BPR1J-340 also demonstrated pronounced tumor growth inhibition and regression in FLT3-ITD(+) AML murine xenograft models. The combination treatment of the HDAC Inhibitor vorinostat (SAHA) with BPR1J-340 synergistically induced Apoptosis via Mcl-1 down-regulation in MOLM-13 AML cells, indicating that the combination of selective FLT3 kinase inhibitors and HDAC inhibitors could exhibit clinical benefit in AML therapy. Our results suggest that BPR1J-340 may be further developed in the preclinical and clinical studies as therapeutics in AML treatments.