Genes that were upregulated by demethylation but not methylated included genes that have been described previously as TSGs in other cancer types (e.g. BAP1 (Jensen and Rauscher, 1999), IGSF4 (Kikuchi et al, 2006), RRM2 (Gautam and Bepler (2006)), PMAIP1 (Shibue et al, 2003), claudin-1; (Higashi et al, 2007) and ICAM1; (Georgolios et al, 2006)). This evidence concerns the gene RRM2 and cancer.