These authors used a large cohort of ccRCC tumor tissues (380 on a tissue microarray, an additional 57 ccRCC from patients treated with antiangiogenic therapy for response associations analysis) to assess the expression of HAF (hypoxia-associated factor, which regulates HIFs), HIF1α and HIF2α in ccRCC. The gene discussed is EPAS1; the disease is nonpapillary renal cell carcinoma.