OBJECTIVETo investigate the relationship between the expression of vascular endothelial growth factor (VEGF) and fms-like tyrosine kinase (Flt-1) mRNA and tumor progression, microvessel density and survival time in gastric carcinoma.

METHODSIn situ hybridization and immunohistochemical techniques were used to detect the gene expression of VEGF, Flt-1 and CD34 in 118 gastric carcinoma specimens.

RESULTSIn situ hybridization revealed that positive expression rates of VEGF and Flt-1 mRNA in gastric carcinoma were 54.24% and 55.9% respectively. There was a significant correlation between the expression of VEGF and Flt-1 mRNA and growth pattern, the depth of tumor invasion, vessel invasion, lymph node and distant metastasis (P < 0.01). The mean tumor microvessel densities (MVD) in patients of stage T3-T4 or those with vessel invasion, lymph node and distant metastases were significantly higher than those of stage T1-T2 and without metastases (P < 0.01). MVD value was correlated with the expression levels of VEGF and Flt-1 mRNA (P < 0.01). The mean survival time and survival rate of patients with positive mRNA expression and mean MVD value >or=54.9/mm2 were significantly lower than those of patients with negative mRNA expression and mean MVD value < 54.9/mm2.

CONCLUSIONSThe expression of VEGF and Flt-1 can promote tumor angiogenesis and contribute to tumor invasion and metastasis in gastric carcinoma. VEGF and Flt-1 may serve as valuable indicators of biological behaviour, prognosis and target of gene therapy in gastric carcinoma.