The Association of FLT3-ITD Gene Mutation with Bone Marrow Blast Cell Count, CD34, Cyclin D1, Bcl-xL and hENT1 Expression in Acute Myeloid Leukemia Patients

Background & Objective:  FLT3-ITD has been recently used as a molecular prognostic marker for risk classification in acute myeloid leukemia (AML) therapy. In this study we aimed to investigate the association of FLT3-ITD gene mutation with bone marrow blast cell count, CD34 expression as malignant cell burden, cyclin D1 and Bcl-xL expressions as indexes of cell proliferation and anti-apoptosis and human equilibrative nucleoside transporter 1 (hENT1) expression as cytarabine transporter during AML treatment. Methods:  We investigated FLT3-ITD mutations, bone marrow blast cell count, CD34, cyclin D1, Bcl-xL and hENT1 expression in bone marrow aspirates from 22 de novo AML patients in a cross sectional study. Results:  FLT3-ITD mutations were observed in 5 out of 22 de novo AML patients (22.7%). Patient with FLT3-ITD mutations had higher blast cell counts (79.5% vs 56.1%, p =0.004). In patients with FLT3-ITD mutations, CD34 and cyclin D1 expressions were higher (MFI 328.80 vs 25.78, p =0.003 and MFI 74.51 vs 57.15 p =0.005) than the patients without mutations. hENT1 expression in AML with FLT3-ITD mutation was lower (MFI 29.64 versus 56.32, p =0.0000) than in mutation-free AML. There was no significant difference in Bcl-xL expression between patients with and without mutations (p =0.61). Conclusion:  A significant association was found between FLT3-ITD gene mutations in AML patients with bone marrow blast cell count, CD34, cyclin D1 and hENT1 expressions, however no association was obtained with Bcl-xL expression. These findings support the role of such mutation in pathogenesis of AMLand its contribution in rearrangement of standard therapy with cytarabine in management of AML.