Background & objective: Lymphatic metastasis affects the prognosis of colorectal cancer patients. The binding of vascular endothelial growth factor-C (VEGF-C) and vascular endothelial growth factor receptor-3 (VEGFR-3) promotes lymphangiogenesis and lymphatic metastasis. This study was to investigate the interrelation of VEGF-C, VEGFR-3 and lymphangial density (LAD), and to identify their correlations to clinicopathologic factors of colorectal cancer.
Methods: The tissue microarrays containing 105 cases of colorectal cancer and 105 cases of normal colorectal tissue were produced separately. The expression of VEGF-C and VEGFR-3 was detected by immunohistochemistry; LAD was assessed through Podoplanin immunohistochemical staining.
Results: The positive rates of VEGF-C and VEGFR-3, and LAD were significantly higher in colorectal cancer than in normal colorectal tissue (61.0% vs. 22.8%, P<0.01; 55.2% vs. 20.0%, P<0.01; 8.91+/-3.75 vs. 6.68+/-1.38, P<0.01). The expression of VEGF-C had no correlation to that of VEGFR-3. LAD was significantly higher in VEGF-C-positive colorectal cancer than in VEGF-C-negative colorectal cancer (10.89+/-3.36 vs. 5.83+/-1.67, P<0.01). VEGF-C was up-regulated in colorectal cancer at Dukes'C stage, or with lymph node metastasis or distant metastasis; VEGFR-3 was up-regulated and LAD was higher in colorectal cancer at Dukes'C stage, or with lymph node metastasis.
Conclusion: VEGF-C and VEGFR-3 are related with the lymphangiogenesis, lymphatic metastasis, and progression of colorectal cancer.