Based on the results of MSP and qRT‐PCR, the methylation and mRNA expression of PON1 were verified and the results showed that the treatments of 1 μmol/L 5‐Aza‐dC and 100 nmol/L TSA in SKRC39/sunitinib cells had relative lower methylation level and higher expression level compare with the other two RCC cells (Figure 4D‐E). This evidence concerns the gene PON1 and renal cell carcinoma.