ZFP42 and nonpapillary renal cell carcinoma: Six exact Infinium probe CpG sites in ccRCC-specific CIMP marker genes (Probe ID: cg06274159 for the ZFP42 gene, cg03975694 for the ZNF540 gene, cg08668790 for the ZNF154 gene, cg01009664 for the TRH gene, cg22040627 for the SLC13A5 gene, and cg19246110 for the ZNF671 gene) were examined using the MassArray system in the learning cohort (Additional file 6; Figure S2).