OBJECTIVE To observe the inhibitory effect of Gypsophila oldhamiana gypsogenin(GOG)on Lewis lung cancer growth,and to investiga te the mechanism of its anti-tumor effect.METHODS A mouse model bearing Lewis lung cancer was used.The 5 experimental groups were divided into a positive control(cis-diaminedichloroplatinum),a negative control,and high,medium and low-GOG dosage groups.The inhibitory action of GOG administration on the lung cancer was observed.After GOG treatment,the lungs were taken out and a lung coefficient computed.The expressions of VEGF,Bcl-2,Bax and P53 in the cancers were determined using immunohistochemical staining.RESULTS The tumor weight of the mice given various doses of GOG was significantly lower compared to the negative-control group(P<0.01),and the lung coefficient of the groups given high and low GOG doses was significantly lower compared to the negative-control group (P<0.01).Immunohistochemical results were shown as follows：I)The VEGF and Bcl-2 expressions in the GOG groups were significantly lower than that of the negativecontrol group(P<0.05);ii)Bax expression in the groups treated with high and medium GOG doses was significantly higher compared to the negative-control group(P<0.05);iii)The mutant P53 expression in the GOG-treated groups was significantly lower compared to the negative-control group (P<0.05).CONCLUSION GOG can inhibit the growth and metastasis of Lewis lung cancel and may exert its mechanism of tumor control by inhibition of tumor angiogenesis and induction of apoptosis.