Study On The Apoptosis-inducing Effects Of Active Compounds Of ALK From Ginseng Herb In Human Acute Leukemic K562 Cells

Objective:To investigate the effects of ALK on both proliferation-inhibiting and apoptosis-inducing in human acute leukemic K562 cells.Methods:MTT assay and semi-solid colony culture method were used to detect the growth inhibition of K562 cells exposed to ginsenoside extract at different dosages.The apoptosis rates of K562 cells were analyzed by flow cytometry after Annexin V/PI staining.Typical apoptotic morphological changes in the ginsenoside extract-treated K562 cells were observed by Wright-Giemsa staining.The gel electrophoresis of DNA ladder was used to analyze the bands of DNA degradation.The expression level of Bcl-2?caspase-3?caspase-9?survivin?Cyt C of K562 cells were tested by Western-blot;besides,immunohistochemistry was further used to detect the expressions of Cyt C and Bcl-2.Results:MTT assay and semi solid colony culture method showed that the proliferation of K562 cells was effectively inhibited by ginsenoside extract in a dosage dependent manner.The proliferation rate of K562 cells treated with 100mg/L ginsenoside extract within 72 hours were(57.46±1.06)%?(61.00±1.00)%(P<0.05),Exposed 75mg/L and 100mg/L ginsenoside extract for over 48 hours,the positive rates of Annexin V were respectively(9.07±2.08)%,(15.81±1.97)%,which were statistically significant when compared with the control group(2.52±0.10)%(P<0.05).Typical apoptotic morphological changes,such as chromatin condensation,marginalization,nuclear membrane lysis,divided chromatin and apoptotic bodies,were found by Wright-Giemsa staining in the ALK-treated K562 cells for 72 hours.DNA agarose gel electrophoresis analysis showed that typical apoptosis-specific DNA degradation ladder significantly appeared in 100mg/L ALK treated K562 cells.Western blotting and immunohistochemistry showed that different dosages of ALK for 72 hours caused up-regulation of Cyt C and down-regulation of Bcl-2,and survivin and inactive form of caspase-3 protein were increased in K562 cells.Compared with the control group,the procaspase-9 was decreased,while the actived caspase-9 was increased in K562 cells(P<0.05).Conclusion:It is concluded that the ALK can inhibit the proliferation of K562 cells and induce the apoptosis in K562 cells,Bcl-2,caspase-3,caspase-9,surviving and Cytc C may be involved in this process.