HIF1A and hemangioblastoma: Immunohistochemical (IHC) staining analysis revealed that both RCC and hemangioblastoma tissues exhibited apparent elevated levels of HIF1α and HIF2α, compared to the para-tumor renal tissue, and also observed that Epithelial-to-mesenchymal transition (EMT) markers Vimentin upregulated and E-Cadherin downregulated in the tumor specimens (Fig. 2D).