Effects Of Arsenic Trioxide On Proliferation, Apoptosis And Expression Of Vegf In K562 Cells

OBJECTIVE To investigate the effects of Arsenic trioxide (As2O3) on proliferation,apoptosis and expression of the vascular endothelial growth factor (VEGF) of K562 cells.METHODS The K562 cells were cultured in RPMI1640 at different concentration of As2O3 (0μmol/l,0.5μmol/l,2.0μmol/l,5.0μmol/l) and harvested in 24 h,48 h,72 h. K562 cell was observed on phasecontrast microscope. Cell morphology was assayed by Wright's stain and AnnexinⅤ-FITC/PI fluorescent vital staining.The viability of the cell was tested by MTT assay. The VEGF protein was examined by immunohistochemistry assay.The cell apoptosis was examined by flow cytometry. VEGF levels were measured with ELISA in cultural supernatants of K562 cells。RESULTS①Our data showed that at the concentration of 0.5μmol /l,the cell could grow well without significant growth inhibition and apoptosis (P> 0.05). But, at the concentration of 2.0-5.0μmol/l, As2O3 was inhibited the K562 cells proliferation while the apoptosis of the cell became obvious (P<0.05). The growth inhibition rate and apoptosis rate of K562 cells increased with the increasing concentration of As2O3, for the same time point. While, at the same concentration of As2O3, the growth inhibition rate and apoptosis depended on the prolongation of incubation time.②At the concentration of 0.5μmol/l of As2O3, expression of the VEGF of K562 cells had no significant down-regulate (P>0.05).While at the concentration2.0-5.0μmol/l of As2O3 obvious down-regulate VEGF expression (P <0.05).The expression of the VEGF of K562 cells was down-regulated with increased concentration of As2O3 for the same time point. While it was down-regulated with prolongation of the incubation time (P<0.05).CONCLUS ION As2O3 could inhibit proliferation and induce apoptosis of K562 cells in a dose-and time-dependent. As2O3 could also decrease the VEGF protein production and down-regulate VEGF expression in K562 cells.