[The role of cyclooxygenase-2 and vascular endothelial growth factor-C in lymphatic metastasis of gastric cancer].

OBJECTIVE: It has been known that cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF)-C are closely related with the development of tumors. To investigate the expression of COX-2 and VEGF-C in gastric cancer and the correlation between them. METHODS: Sixty-four paraffin-embedded gastric cancer samples and 22 flesh gastric cancer samples were tested with using immunohistochemistry method and the reverse transcription-polymerase chain reaction technology respectively. RESULTS: The mean expressive density of COX-2 and VEGF-C mRNA in gastric cancer were both significantly higher than those in non-cancerous gastric mucosa (1.363 +/- 0.351 vs 0.763 +/- 0.304, 0.972 +/- 0.331 vs 0.314 +/- 0.215, P < 0.001). The positive rates of COX-2 and VEGF-C in 64 gastric cancer samples were 72% and 64% respectively. Their expression in the groups of lymph-node metastasis were higher than that of the non-lymph-node metastasis groups respectively (P < 0.05). Moreover, there was a close correlation between COX-2 and VEGF-C expression levels (P < 0.05). CONCLUSIONS: There are high COX-2 and VEGF-C expression in gastric cancer. Gastric tumor tissues that produce VEGF-C may have a higher lymphatic invasion and metastatic potential. COX-2 may participate in VEGF-C lymphangiogenic pathway and the high expression of them may play an important role in the lymphatic proliferation and spread in gastric cancer.