EPAS1 and nonpapillary renal cell carcinoma: Finally, while specific inhibitors of HIF-2α are available and are currently being tested in clinical trials25–27, our findings demonstrating the importance of HIF-1α for ccRCC formation argue that the development of specific inhibitors of HIF-1α or of new specific dual HIF-1α/HIF-2α inhibitors would also be desirable and may have therapeutic benefit in ccRCC.