APOLD1 and testicular germ cell tumor: One study reported hypermethylation of Apold1 in testicular germ cell tumors and in testicular embryonal carcinoma NT2 cells, lower Apold1 expression in two types of testicular tumor (seminoma and embryonal carcinoma), and increased Apold1 expression in response to treatment with the demethylating agent 5-azacytidine [81].