1. |
- Kazi, Julhash U, et al.
(author)
-
ABL2 suppresses FLT3-ITD-induced cell proliferation through negative regulation of AKT signaling
- 2017
-
In: Oncotarget. - : Impact Journals, LLC. - 1949-2553. ; 8:7, s. 12194-12202
-
Journal article (peer-reviewed)abstract
- The type III receptor tyrosine kinase FLT3 is one of the most commonly mutated oncogenes in acute myeloid leukemia (AML). Inhibition of mutated FLT3 in combination with chemotherapy has displayed promising results in clinical trials. However, one of the major obstacles in targeting FLT3 is the development of resistant disease due to secondary mutations in FLT3 that lead to relapse. FLT3 and its oncogenic mutants signal through associating proteins that activate downstream signaling. Thus, targeting proteins that interact with FLT3 and their downstream signaling cascades can be an alternative approach to treat FLT3-dependent AML. We used an SH2 domain array screen to identify novel FLT3 interacting proteins and identified ABL2 as a potent interacting partner of FLT3. To understand the role of ABL2 in FLT3-mediated biological and cellular events, we used the murine pro-B cell line Ba/F3 as a model system. Overexpression of ABL2 in Ba/F3 cells expressing an oncogenic mutant of FLT3 (FLT3-ITD) resulted in partial inhibition of FLT3-ITD-dependent cell proliferation and colony formation. ABL2 expression did not alter the kinase activity of FLT3, its ubiquitination or its stability. However, it partially blocked FLT3-induced AKT phosphorylation without affecting ERK1/2 and p38 activation. Taken together our data suggest that ABL2 acts as negative regulator of signaling downstream of FLT3.
|
|
2. |
- Moharram, Sausan A., et al.
(author)
-
Efficacy of the CDK inhibitor dinaciclib in vitro and in vivo in T-cell acute lymphoblastic leukemia
- 2017
-
In: Cancer Letters. - : Elsevier BV. - 0304-3835. ; 405, s. 73-78
-
Journal article (peer-reviewed)abstract
- T-cell acute lymphoblastic leukemia (T-ALL) is a heterogeneous disease of the blood affecting children, adolescents and adults. Although current treatment protocols for T-ALL have improved overall survival, a portion of T-ALL patients still experiences treatment failure. Thus, the development of novel therapies is needed. In this study, we used several patient-derived T-ALL cell lines to screen for an effective drug for T-ALL. Using a panel of 378 inhibitors against different kinases, we identified the CDK inhibitor dinaciclib as a potential drug for T-ALL. Dinaciclib treatment significantly reduced cell viability and completely blocked colony formation. Furthermore, cells treated with dinaciclib showed decreased expression of several pro-survival proteins including survivin, cyclin T1 and c-MYC. Dinaciclib treatment also increased accumulation of cells in G2/M phase and significantly induced apoptosis. Finally, dinaciclib extended survival of mice in a T-ALL cell xenograft model. Collectively, these data suggest that the CDK inhibitor dinaciclib is an active drug for T-ALL in the preclinical settings.
|
|
3. |
|
|