Recent studies showed that HIF-1α antagonizes c-Myc function and inhibits VHL-deficient renal cell carcinoma (RCC) growth [5], while HIF-2α enhances c-Myc activity in WT-8 and 786-O cells that predominantly express HIF-2α (but little HIF-1α) and promotes VHL-deficient RCC tumorigenesis [6]. This evidence concerns the gene HIF1A and hereditary clear cell renal cell carcinoma.