High-grade CC-RCC showed a higher ECP% (P=0.049), a higher TCP% (P=0.009), a higher VEGF protein expression (P<0.001), a lower MVD (P< 0.001) and a lower HIF-1α protein expression (P=0.002) than low-grade CC-RCC. Here, HIF1A is linked to renal cell carcinoma.