SOX2 and testicular germ cell tumor: Based on the critical review of the literature, 12 TGCT-related genes were chosen for this study, six of which are already used in histopathological diagnostics of TGCTs (OCT4, c-KIT, NANOG, SOX2, SOX17, and SALL4) and six as prominent biomarkers (MGMT, RASSF1, HOXA9, CFC1, PRSS21, and MAGEC2).