Effects Of Chrysin On The Proliferation,differentiation And Apoptosis Of Human Acute Myeloid Leukemia Hl-60 Cell Line

Objective To investigate whether chrysin(ChR) suppress proliferation and induce the differentiation and apoptosis in human acute myelogenous leukemia HL-60 cell line.Methods Human acute myelogenous leukemia HL-60 cell line was cultured in vitro. The lactate dehydrogenase activity of cell medium was evaluated by automatic biochemisitry analyzer. The cell viability was evaluated by MTT assay. The biochemistrical characteristics of differentiation were detected by NBT reduction reaction. Expression of cell surface differentiation antigen CD11b were observed by indirect fluorescence microscope. The percentage of sub-G1 cells was determined by flow cytometry using PI fluorescence staining. Caspase-3 activity was determined using colorimetric method. The level of phosphorylation Akt protein was analyzed by Western blot.Results The Cytotoxicity assay based on a LDH release showed that EC50 of cytotoxicity in human acute myelogenous leukemia HL-60 cells by ChR and ATRA for 24h were 171μmol/L and108μmol/L, respectively. MTT assay indicated that ChR and ATRA inhibited the viability of HL-60 cells, in a concentration-dependent manner, with IC50 value of that were 18.4μmol/L and 2.2μmol/L, respectively. ChR induced HL-60 cells to be reinforced the potency of NBT reduction reaction, but the effect was weak than ATRA. ChR possesses the ability to induce HL-60 differentiation towards granulocyte series and expression of the membranaceous antigen CD11b in a concentration-dependent manner. Flow cytometry(FCM) analysis with PI stainning indicated that ChR and ATRA efficiently induced apoptosis of human acute myelogenous leukemia HL-60 cells. Caspase-3 activity in HL-60 cells treated with ChR and ATRA were raised in comparison with medium group, in a concentration-dependent manner. Western blot analysis indicated that ChR reduced the level of phosphorylation Akt protein, in a concentration- dependent manner.Conclusion1. ChR possesses the effects of inhibition of proliferation and induction of differentiation and apoptosis in human acute myelogenous leukemia HL-60 cell line, in a concentration- dependent manner.2. The induction of apoptosis by ChR in human acute myelogenous leukemia HL-60 cells was associated with down-regulation of the level of phosphorylation Akt protein.