Expression Of VEGF And MMP-2 In Gastric Carcinoma And Their Relation To Tumor Invasion And Metastasis

Gastric carcinoma is one of the most common malignant tumors in the world. Its mortality rate ranks the first among all the malignant tumors for so many years in China.Gastric carcinoma metastasis is the main cause of patients' death. Angiogenesis is the basis of growth and metastasis of malignant tumor. Vascular endothelial growth factor (VEGF) is a main factor in regulating angiogenesis. It plays an important role in tumor invasion and metastasis. Matrix metalloproteinase-2 (MMP-2) contributes to tumor metastasis by degrading extracellur matrix (ECM). It has been found out that MMP-2 is also-related to angiogenesis and that VEGF upregulates the expression of MMP-2 during angiogenesis, which contributes more to tumor invasionand metastasis. Up to now, the study in the expression of VEGF and MMP-2 in gastric carcinoma and precancerous lesions has not been much reported.Aims: This study evaluated the roles of VEGF and MMP-2 in development, invasion and metastasis of gastric carcinoma as well as their interaction in order to judge the metastasis and prognosis of gastric carcinoma and provide theoretical foundation for clinical therapy.Materials and methods: 68 cases of surgically resected gastric carcinoma samples and 34 cases of biopsies were collected. All the tissues were fixed in 10% neutral formalin and embedded in paraffin. Streptavidin/Peroxidase (SP) technique was used to examine the expression of VEGF and MMP-2 in gastriccarcinoma and precancerous lesions, x --test was used to analyze the data. There is a statistical significance when P<0.05.Results: The positive staining of VEGF is mainly located in cytoplasm. There was positive staining in some membrane and ECM. In chronic superficial gastritis (CSG), chronic atrophic gastritis(CAG) with metaplasia, dysplasia, early gastric carcinoma and advanced gastric carcinoma, the positive rates of VEGF were 27.3%(3/ll), 36.4%(4/ll), 41.7%(5/12), 46.7%(7/15),77.4%(41/53) respectively. There were significant differences (P<0.05) when advanced gastric carcinoma group compared with CSG, CAG with metaplasia, dysplasia, early gastric carcinoma separately. There were no significant differences (P>0.05) when the other groups were compared with each other. In the well-differentiated group, moderately differentiated group and poor differentiated group, the positive rates of VEGF were 72%(18/25), 65%(13/20), 73.9%( 17/23) respectively. There were no significant differences (P>0.05) when the expression of VEGF of these three groups were compared with each other. Of 68 cases gastric carcinoma, in the group without serosa infiltration and the group with serosa infiltration, the positive rates of VEGF were 54.3%(19/35), 87.9%(29/33). There were significant differences (P<0.005) between the two groups. In the group with lymph node metastasis and the group without lymph node metastasis, the ' positive rates of VEGF were 84.2%(32/38), 53.3%(16/30). There were significant differences (P<0.01).The positive staining of MMP-2 is located in both cytoplasm and ECM. In chronic superficial gastritis(CSG), chronic atrophic gastritis(CAG) with metaplasia, dysplasia, early gastric carcinoma and advanced gastric carcinoma, the positive rates of MMP-2were 18.2%(2/11), 27.3%(3/11), 33.3%(/12), 53.3%(8/15), 73.6%(39/53) respectively. There were significant differences (P<0.05) when advanced gastric carcinoma group compared with CSG, CAG with metaplasia, dysplasia separately. There were no significant differences (P>0.05) when the other groups were compared with each other. In the well-differentiated group, moderately differentiated group and poor differentiated group, the positive rates of MMP-2 were 64%(16/25), 70%(14/20), 73.9%( 17/23) respectively. There were no significant differences (P>0.05) when the expression of MMP-2 of these three groups were compared with each other. In the group without serosa infiltration and the group with serosa infiltration, the positive rates of MMP-2 were 57.1%(20/35), 81.8%(27/33). There were significant differences (P<0.05) bet...