AP-2gamma protein expression in intratubular germ cell neoplasia of testis

Although activator protein 2gamma (AP-2gamma) has been reported to be a marker of germ cell tumors of the testis, its relationship to placental alkaline phosphatase (PLAP) and KIT (CD117) protein expression in intratubular germ cell neoplasia (ITGCN) has not been directly compared. In this study, staining of AP-2gamma in 30 cases of ITGCN was examined and compared with that of PLAP and KIT. Both PLAP and KIT were positive in 29 (97%) of 30 cases, whereas AP-2gamma was expressed in 100%. All 3 markers were negative in normal testis (0 of 11 cases). DNA binding sites in the promoter region forAP-2gamma in the PLAP and c-kit genes might explain the concordance of protein expression.