Previous studies also investigated the differences in mRNA levels of hypoxia-inducible factor 1-alpha, endothelial PAS domain protein 1 (also known as hypoxia-inducible factor 2-alpha, HIF2A/EPAS1), and vascular endothelial growth factor A among cancerous tissue, benign hyperplastic changes in the ovary, and normal tissue, but also in other endometrial cancer [30,57]. This evidence concerns the gene EPAS1 and endometrial cancer.