HIF1A and cancer: Although HIF-1α is expressed in renal tubules and neuronal cells, HIF-2α was detected in nonparenchymal cells including glomerular, kidney peritubular endothelial cells and fibroblasts, and brain endothelial and glial cells.11 Furthermore, HIF-2α expression has been shown to differ from that of HIF-1α in many cancers.