KDR and cancer: When evaluating the co-expression between the expression of the ligands and the receptors (Table 5), VEGF-A was more frequently expressed in cancer cells expressing VEGFR-1 or VEGFR-3 (p = 0.008 and p < 0.001, respectively), VEGF-C was more frequently expressed in cancer cells expressing VEGFR-2 (p < 0.001), and VEGF-D was more frequently expressed in cancer cells expressing VEGFR-1 or VEGFR-3 (p = 0.002 and p < 0.001, respectively).