Objective: To study the antitumor effect of ethanol extract YM-J and polysaccharide YM-S of maize. Method: The inhibitory effects on BGC-823

SMMC7721 human cancer cell lines were observed by detecting MTT absorbance value and calculate IC50 value. Human gastric cancer cell line BGC 803 nude-mouse transplanted tumor model and H22 mouse liver cancer transplanted tumor model were used. The animals were given maize ethanol extract YM-J and maize polysaccharid YM-S by gavage(400

200 mg ·kg-1

daily

19 d for BGC 803

10 d for H22)

in order to observe the antitumor effect in vivo . Result: YM-J and YM-S displayed strong growth inhibitory effects on human gastric cancer cell line BGC-823

the IC50 were 24.16

12.61 μg ·mL-1

respectively. Meanwhile

YM-J and YM-S displayed weak inhibitory effects on human liver cancer cell line SMMC7721 with IC50 which were 127.42 and 1 352.72 μg ·mL-1. YM-J had obvious inhibition to the tumor growth

the highest inhibition rate were 40.27% and 44.69% on above two model in vivo

respectively. YM-S displayed inhibition on H22 mouse liver cancer transplanted tumor model in some degree with 38.89% inhibition rate

however

the highest inhibition rate on human gastric cancer cell line BGC 803 nude-mouse transplanted tumor model was only 25.96%. Conclusion: Maize ethanol extract YM-J and maize polysaccharide YM-S have obvious antitumor effect in vivo and in vitro ; ethanol extract YM-J has stronger inhibitory effects on liver cancer and gastric cancer than polysaccharide YM-S.