In addition to this, several studies have shown that methylation of genes, such as cyclin-dependent kinase inhibitor 2A (CDKN2A), O-6-methylguanine DNA methyltransferase (MGMT), adenomatous polyposis coli (APC), and tumor protein P53 (TP53), all of which are associated with tumorigenesis and progression, have been observed in FH-deficient RCC [45], which may explain the aggressiveness and poor prognostic outcome for patients observed in the clinic. This evidence concerns the gene APC and renal cell carcinoma.