OBJECTIVETo observe the effects of angiotensin converting enzyme inhibitors (ACEI) and angiotensin II receptor blocker (ARB) on tumor growth and angiogenesis in implanted gastric cancer mouse model, and to explore the probable mechanism of ACEI and ARB anticancer effect.

METHODSNude mouse model with human gastric cancer was established by subcutaneously inoculating human gastric cancer cell line SGC-7901. One week later, 60 mice were randomly divided into 5 groups: control group, perindopril group, captopril group, losartan group, and valsartan group. These groups respectively received the normal saline, perindopril (2 mg/kg), captopril (5 mg/kg), losartan (50 mg/kg), valsartan (40 mg/kg) by gavage once a day. Twenty-one days after treatment the tumors were removed and the tissues were stained by immunohistochemistry method to observe the expression of VEGF, MMP-7 and microvessel density (MVD).

RESULTSIn all the ACEI and ARB groups, tumor volumes were significantly inhibited and MVD also decreased significantly as compared with control group (all P<0.01). In captopril and perindopril groups, the expression of VEGF and MMP-7 decreased significantly as compared with control group(all P<0.05). In losartan and valsartan group, the expressions of VEGF were significantly decreased as compared with control group (all P<0.05). The expressions of MMP-7 between ARB groups and control group were not significantly different.

CONCLUSIONACEI and ARB can inhibit the tumor growth in gastric cancer model and suppress the angiogenesis of the tumor.