Clinical significance of co-expression of VEGF-C and VEGFR-3 in non-small cell lung cancer

Objective To investigate the relationship between vascular endothelial growth factor C (VEGF-C) expression, VEGFR-3 expression, lymphangiogenesis and angiogenesis in human non-small cell lung cancer (NSCLC).Methods Seventy-six NSCLC samples were stained for VEGF-C, VEGFR-3 and CD34 with immunohistochemical methods. Assessment of lymphatic vessel density (LVD) and microvessel density (MVD) was performed. The expressions of VEGF-C in 24 fresh NSCLC samples were determined with Western blot assay.Results Of the 76 NSCLC cases, 55 were VEGF-C positive and 40 were VEGFR-3 positive in cancer cells. A significant positive correlation was found between VEGF-C expression and VEGFR-3 expression in cancer cells (P<0.05). VEGF-C expression was negatively associated with differentiation of tumor cells (P<0.05). VEGF-C expression and VEGFR-3 expression were positively associated with lymph node metastasis and lymphatic invasion (P<0.05). LVD was positively related to VEGF-C expression, lymph node metastasis, lymphatic invasion and clinical stage (P<0.05). There was a significant correlation between LVD and MVD (R=0.732, P<0.05). Patients with positive VEGF-C expression had worse outcomes than those with negative VEGF-C expression (P<0.01).Conclusions In NSCLC, VEGF-C and VEGFR-3 are related to the lymphangiogenesis, angiogenesis, and occurrence and development of lung cancers. VEGF-C expression could be a useful predictor of poor prognosis in NSCLC.