To study this, we measured the expression of EGFR in two independent clones of MDA-MB-231 breast cancer cells with a stable knockdown of PHD2 (clones #3 and #4), which displayed a normoxic accumulation of HIF-1α and HIF-2 α as previously described (Supplementary Figure 2) [28]. The gene discussed is EGFR; the disease is breast carcinoma.