OBJECTIVETo investigate mRNA expression of integrin beta3 in gastric carcinoma, its correlation with microvascular density (MVD), growth-pattern, invasion, metastasis and prognosis.

METHODSIn situ hybridization and immunohistochemistry techniques were used to study the expression of integrin beta3 mRNA and CD34 protein in 105 gastric carcinoma specimens.

RESULTSIn situ hybridization revealed a 30% (6/20) positive rate of integrin beta3 mRNA in non-tumor gastric mucosa, which was significantly lower than that of the gastric cancer group (61.0%, 64/105, chi(2) = 8.85, P = 0.037); In infiltrating type cases (70.2%, 40/57), stage III - IV (72.1%, 44/61), lymphatic metastasis (68.6%, 48/70) and distant metastasis (85.7%, 36/42), the positive expression rates were significantly higher than those of the expanding type (chi(2) = 14.97, P = 0.002), stage I - II (chi(2) = 15.21, P = 0.015), non-lymphatic metastasis (chi(2) = 17.89, P = 0.025) and non-distant metastasis (chi(2) = 20.22, P = 0.005; chi(2) = 21.35, P = 0.035); its mean MVD was also significantly higher than that of the expanding type (t = 10.105, P = 0.001), stage I approximately II (t = 5.961, P = 0.001), non-lymphatic metastasis (t = 3.819, P = 0.01)and non-distant metastasis (t = 10.578, P = 0.001; t = 7.882, P = 0.001), respectively; The mean MVD (41.02 +/- 8.55)/0.72 mm(2) of the integrin beta3 mRNA positive expression group was significantly higher than (25.26 +/- 11.25)/0.72 mm(2) of the negative expression group. There was a positive relation between MVD and integrin beta3 mRNA expression in the tumor (r(s) = 0.316, P = 0.001). The mean survival time in cases with positive integrin beta3 mRNA expression or MVD value >or= 39.5 was significantly shorter than that in cases with negative expression or MVD value < 39.5.

CONCLUSIONSIntegrin beta3 expression correlates with enhanced tumor angiogenesis and may play a role in the invasion and nodal metastasis of gastric carcinoma, therefore it may serve as a prognostic marker of gastric cancer.