While this specific cancer type might be a notable exception, on the basis of our data, most cancer types appear to possess intrinsic HIFα isoform sc-heterogeneity, implying that either an unspecific HIF heterodimerization inhibitor or a combination therapy targeting both HIF-1 and HIF-2 will be necessary to successfully treat hypoxic tumor cells. The gene discussed is HIF1A; the disease is neoplasm.