TET2 Gene Expression in Bone Marrow Cells in Myelodysplastic Syndromes Patients and the Effect of Silencing TET2 by siRNA On Biological Characteristics of Healthy CD34+ Cells

Abstract Abstract 4934 Objective To investigate the expression of TET2 mRNA in bone marrow mononuclear cells(BMMNC), CD3+ T cells and CD34+ cells of patients with myelodysplastic syndrome(MDS)and to study the effect of silencing TET2 by Small interfering RNA (siRNA) on the biological characteristics of CD34+ cells. Methods CD3+ T cells and CD34+ cells were sorted by magnetic activated cell-sorting system. The expression of TET2 mRNA was detected by qPCR. The silencing effect of RNA interference (RNAi) on TET2 expression was identified by qPCR and Western blot analysis. The cell cycle kinetics and cell apoptosis were detected by flowcytometry. Results The expressions of TET2 mRNA in BMMNC, CD3+ T cells and CD34+ cells were down-regulated in MDS compared with that in controls. The siRNA targeting TET2 suppressed the expression of TET2 in CD34+ cells. Meanwhile, the proliferation activity was significantly enhanced and the apoptosis rate was declined in cells which transfected with TET2 siRNA as compared to those of the cells transfected with scrambled siRNA and control cells. Conclusions The mRNA expressions of TET2 in BMMNC, CD3+ T cells and CD34+ cells of MDS patients were decreased. Suppression of TET2 expression renders the CD34+ cells harboring more aggressive phenotype. This preliminary finding suggests that CD34+ cells lowering expression of TET2 may play an oncogenic role on myeloid tumor. Disclosures: No relevant conflicts of interest to declare.