Abstract:

Objective    To explore expressions of vascular endothelial growth factor(VEGF) A and D in gastric cancer, pericancerous gastric tissue and normal gastric tissues and their relationship with progression of gastric carcinoma.To observe expression of podoplanin in lymphatic endothelial cells in gastric carcinoma  so as to provide morphological data for the study of the molecular mechanism of tumor metastasis. Methods     The immunohistochemical SP method was used to examine expressions of VEGF-A and D in 54 gastric cancer tissues,  54 peri-cancerous gastric tissues, 12 normal gastric tissues, and expression of podoplanin in gastric carcinoma and normal gastric tissue.Lymphatic microvessel density(LMVD) in gastric cancer tissue and  pericancerous gastric tissues were calculated. Results    Positive expression rates of VEGF-A and D in gastric cancer tissues and peri-cancerous gastric tissues were significantly higher than those in normal gastric tissues (P<0. 01), expressions of VEGF-A and D in the gastric cancer group and the lymph node metastasis group were significantly different(P<0. 05). And expressions of VEGF-A and D  were of significantly positivecorrelation(r=0.365,P=0.007). Expressions of VEGF-A and D in gastric carcinoma were positively correlated with lymph node metastasis (P<0. 01 ), podoplanin was not stained in blood vessels but was positively expressed in gastric carcinoma lymphatics. LMVD of gastric carcinoma tissues and pericancerous gastric tissues was obviously higher than that in normal gastric tissues. MLVD detected from the VEGF-A, D positive group respectively(9.23±2.49)，(9.29±2.18) was significantly higher than that detected from the VEGF-A, D negative group respectively(7.53±1.81), (7.44±1.88). Conclusion     High expressions of VEGF-A and VEGF-D in gastric cancer cells are closely related to lymph nodemetastasis. Podoplanin is selectively expressed in lymphatics of gastric carcinoma and could correctly distinguish blood vessels from lymphatic vessels. It could be regarded as a specific marker of lymphatic vessels. LMVD of the VEGF-A and D positive groups increases in gastric carcinoma， therefore， the increase of the number of lymphatic vessels likely contributes to their synergism.

Key words: Gastric cancer;Vascular endothelial growth factor-A; Vascular endothelial growth factor-D; Ppodoplanin; Lymphatic vessel; Lymphatic micro-vessel density