Objective: To explore the effect and mechanism of hawthorn extract on apoptosis of hepatoma cells HepG2 in vitro. Method: Ethonal fraction was extracted from hawthorn

then HepG2 cells were treated by hawthorn extract at concentrations of 0.1

0.2

0.4 and 0.8 g · L-1 for 24

48 and 72 h. Effect of the extract on hepatoma cells activity was detected by 3-(4

5-dimethyl-2-thiazolyl)-2

5-diphenyl-2-H-tetrazolium bromide (MTT) assay;apoptotic rate was measured by flow cytometry after HepG2 cells were treated by hawthorn extract for 48 h. Gene expressions of cysteinyl aspartate specific proteinase (Caspase-3)

B-cell lymphoma-2 (Bcl-2)

and Bax were detected by real-time PCR;protein expressions of cleaved-caspase3

Bcl-2 and Bax were detected by Western blot. Result: Hawthorn extract significantly inhibited the activity of HepG2 cells

and induced apoptosis in time-and concentration-dependent manners. Bcl-2 expression was inhibited in mRNA and protein level

while Bax and Caspase-3 were up-regulated by extract. Conclusion: Hawthorn extract could inhibit proliferation and promote apoptosis of HepG2 cells

and its mechanism may be associated with increasing expressions of Bax and Cleaved-Caspase-3 and reducing Bcl-2/Bax ratio.