Four renal developmental transcription factors—GATA binding protein 3 (GATA3, AI796169), Transcription factor CP2-like 1 (TFCP2L1, AW195353), transcription factor activating protein -2β (TFAP2B, NM_003221) and Doublesex - mab-3 related transcription factor 2 (DMRT2, AF284225)—were significantly down-regulated in ccRCC (Fig. S1) and validated in another independent data set by qPCR consisting of 15 patient-matched normal renal and ccRCC tissues (Fig. 2a: yellow arrows). This evidence concerns the gene TFCP2L1 and nonpapillary renal cell carcinoma.