Expression of vascular endothelial growth factor C (VEGF-C) and VEGF receptor-3 in human prostate cancer is associated with regional lymph node metastasis

BACKGROUND. Vascular endothelial growth factor C (VEGF-C) and its receptor, VEGFR-3, have been implicated as important factors in the formation of lymphatic vessels and recent evidence suggests that tumor lymphangiogenesis promotes lymphatic metastasis. METHODS. The expression of VEGF-C and VEGFR-3 was examined in 22 human prostate cancer specimens with immunohistochemistry. A semi-quantitative scoring system was used for evaluation of staining. RESULTS. Expression of VEGF-C was stronger in prostate cancer areas in comparison to adjacent benign glands. In addition, patients with lymph node metastases had a significantly higher expression of VEGF-C than patients without lymph node metastases. Interestingly, VEGFR-3 was expressed in malignant prostate epithelial cells and its expression was significantly higher in the lymph node positive group compared to the lymph node negative group. CONCLUSIONS. The results of the present study indicate that increased expression of VEGF-C and VEGFR-3 play a role in prostate cancer progression and in metastasis to regional lymph nodes.