Top pRCC-specific candidates included sclerostin domain-containing protein1 (SOSTDC1)91 and polymeric immunoglobulin receptor (PIGR), further validated in the pan-RCC RNA-seq data from a combined cohort of TCGA plus MCTP (n = 1,000) (Figures 6B, S6A, and S6B). This evidence concerns the gene PIGR and renal cell carcinoma.