KDR and melanoma: Among ECs, kidney tumor tissues contained the highest fraction of tip ECs (C1_ESM1), which is consistent with the fact that kidney cancer responds well to anti-angiogenesis vascular endothelial growth factor (VEGFR) tyrosine kinase inhibitors (TKIs)33, whereas melanoma tissues contained the highest lymphatic ECs (C5_PROX1) consistent with prone lymph node metastasis of melanoma34.