Browsing by Author "Ikeo, Kazuho"

Now showing 1 - 1 of 1
  • Thumbnail Image
    Item
    Inhibition of BCL2A1 by STAT5 inactivation overcomes resistance to targeted therapies of FLT3-ITD/D835 mutant AML
    (Elsevier, 2022) Yamatani, Kotoko; Ai, Tomohiko; Saito, Kaori; Suzuki, Koya; Hori, Atsushi; Kinjo, Sonoko; Ikeo, Kazuho; Ruvolo, Vivian; Zhang, Weiguo; Mak, Po Yee; Kaczkowski, Bogumil; Harada, Hironori; Katayama, Kazuhiro; Sugimoto, Yoshikazu; Myslinski, Jered; Hato, Takashi; Miida, Takashi; Konopleva, Marina; Hayashizaki, Yoshihide; Carter, Bing Z.; Tabe, Yoko; Andreeff, Michael; Medicine, School of Medicine
    Tyrosine kinase inhibitors (TKIs) are established drugs in the therapy of FLT3-ITD mutated acute myeloid leukemia (AML). However, acquired mutations, such as D835 in the tyrosine kinase domain (FLT3-ITD/D835), can induce resistance to TKIs. A cap analysis gene expression (CAGE) technology revealed that the gene expression of BCL2A1 transcription start sites was increased in primary AML cells bearing FLT3-ITD/D835 compared to FLT3-ITD. Overexpression of BCL2A1 attenuated the sensitivity to quizartinib, a type II TKI, and venetoclax, a selective BCL2 inhibitor, in AML cell lines. However, a type I TKI, gilteritinib, inhibited the expression of BCL2A1 through inactivation of STAT5 and alleviated TKI resistance of FLT3-ITD/D835. The combination of gilteritinib and venetoclax showed synergistic effects in the FLT3-ITD/D835 positive AML cells. The promoter region of BCL2A1 contains a BRD4 binding site. Thus, the blockade of BRD4 with a BET inhibitor (CPI-0610) downregulated BCL2A1 in FLT3-mutated AML cells and extended profound suppression of FLT3-ITD/D835 mutant cells. Therefore, we propose that BCL2A1 has the potential to be a novel therapeutic target in treating FLT3-ITD/D835 mutated AML.