APAF1 and testicular germ cell tumor: APAF-1 methylation correlated with tumor grade in bladder cancers, RCC or neuroblastoma, but while a significant increase of APAF-1 methylation was also observed in testicular germ cells tumors, the relative abundant basal APAF-1 methylation in non tumoral tissue leads to a difficult interpretation of its role in tumorigenesis [16,85,113].