A marked downregulation of SIGIRR mRNA levels was observed in ccRCC (n = 72 and p ≤ 0.0001) and in papillary cell carcinoma (n = 32 and p ≤ 0,0001); chromophobe tumor samples and Wilms tumor also expressed lower SIGIRR transcripts compared to their normal counterpart (Figure 2A; n = 25 and n = 5, respectively, p < 0.05). Here, SIGIRR is linked to nonpapillary renal cell carcinoma.