Expression and clinical significance of neuropilin-2 in colorectal cancer: correlation with lymphangiogenic factors

Purpose: Neuropilin-2 is expressed by venous and lymphatic endothelial cells and can bind the lymphangiogenesis-associated ligand vascular endothelial growth factor (VEGF)-C and D. Recently, neuropilin-2 was shown to play a role in lymph node metastasis and cancer promotion. The aim of this study was to determine the clinical relevance of neuropilin-2 expression in colorectal carcinomas. Methods: Immunohistochemical analysis of neuropilin-2 expression of 350 colorectal cancer samples was evaluated using tissue microarray. The relationship between neuropilin-2 expression and other clinicopathological variables were analyzed in colorectal carcinomas. To clarify the role of neuropilin-2 in colorectal cancer lymphangiogenesis, its expression was examined with VEGF-C, VEGF-D, and VEGF receptor 3 expression of the colorectal carcinomas. Results: Neuropilin-2 was detected in 176 of 350 colorectal carcinomas (50.3%). Overexpression of neuropilin-2 was correlated with lymph node metastasis (P=0.041) and VEGF-D expression (P=0.020), but was not correlated with TNM (tumor, node, metastasis) stage, other lymphangiogenic factor expression and survival colorectal cancer patients. Conclusion: Neuropilin-2 expression was correlated with lymph node metastasis and VEGF-D expression in colorectal carcinomas. Our results suggest a possible role of neuropilin-2 in lymphangiogenesis and cancer progression in colorectal carcinomas.