Localization of stage-specific embryonic antigens in hydatidiform mole, normal placenta, and gestational choriocarcinoma.

Murine stage-specific embryonic antigens (SSEA-1, SSEA-3) are well characterized oncofetal antigens and have been identified in several human tumors. The current study was undertaken to determine the localization of SSEA-1 and SSEA-3 in hydatidiform mole, normal human placenta, and gestational choriocarcinoma. SSEA-3 did not react with any cellular components in hydatidiform moles, normal placentas, or choriocarcinoma cell lines. SSEA-1 was detectable in two human gestational choriocarcinoma cell lines, but not in the trophoblastic cells of 10 hydatidiform moles or in nine normal placentas between 6 weeks and term gestation. Therefore, according to this oncofetal marker system, the trophoblast in hydatidiform mole is more like normal trophoblast than gestational choriocarcinoma.