This could be attributed to tumor sample number, given that previous works defined higher HIF1A mRNA in ccRCC, than in pRCC or chRCC (24–26), however, the differential expression analysis we performed on TCGA studies with a larger sample size than any of the referenced studies has also demonstrated no significant differences in HIF1A expression between the analyzed tumor groups. Here, HIF1A is linked to nonpapillary renal cell carcinoma.