EFFECT OF HSP90 INHIBITOR ON PROLIFERATION OF LEUKEMIA CELLS AND MECHANISM OF INDUCING APOPTOSIS

Qian Xu¹, Yanlin Wei^{2, *}

¹Department of Health Service, The First Affiliated Hospital of Nanchang University, Nanchang, PR China - ²Department of Medical, The First Affiliated Hospital of Nanchang University, Nanchang, PR China

Objective: To investigate the effects of 17-acrylamide-17-normethoxygeldermycin (17-AAG), a heat shock protein 90 inhibitor, on the proliferation and apoptosis of leukemia cells. 

Methods: Acute myeloid leukemia (AML) cell lines NB4 and HL60 were treated with 17-AAG at different concentrations. Cell proliferation was detected by CCK-8 colorimetry 24 hours later. Apoptotic capacity and cell cycle were analyzed by flow cytometry. Apoptotic related proteins such as PARP and Caspase 3 were analyzed by Western blotting. 

Results: CCK-8 colorimetric assay showed that 17-AAG had a dose-dependent effect on the proliferation of NB4 and HL60 cell lines. With the increase of 17-AAG concentration, the inhibition of proliferation was more obvious. Annexin V/PI double staining showed that apoptotic ability of AML cell lines NB4 and HL60 treated with 17-AAG was significantly higher than that of DMSO control group. The results of flow cytometry showed that with the increase of 17-AAG concentration and the prolongation of action time, the cell cycle of NB4 cells could be disordered. The cell cycle of NB4 cells in 17-AAG treatment group was stagnated at G2/M phase. Western blotting showed that PARP protein and PARP protein in NB4 cells treated with 17-AAG at different concentrations for 24 hours. The expression level of activated PARP protein (C-PARP) increased significantly (P<0.05).