Expression of Pro-Apoptotic Bax and Anti-Apoptotic Bcl-2 Proteins in Hydatidiform Moles and Placentas With Hydropic Changes

摘要

Morphologic examination still forms the main diagnostic tool in the differential diagnosis ofmolar placentas. However the criteria are subjective and show considerable inter-observer variability amongpathologists. The aim of the present study was to investigate the role of Bcl-2 and Bax immunostaining in thedifferential diagnosis of molar placentas. Bax and Bcl-2 immunohistochemical staining were performed in 19molars (8 partial and 11 complete hydatidiform mole) and 10 non-molar (hydropic abortion) formalin-fixed,paraffin-embedded tissue samples. Ploidy analysis using flow cytometry had confirmed diploidy in hydropicabortions and complete hydatidiform moles and triploidy in partial hydatidiform moles. Bcl-2 expression wasobserved only in syncytiotrophoblasts, No immunoreactivity was detected in Cytotrophoblasts, and stromalcells, the total score averages of Bcl-2 immunoexpression in partial hydatidiform moles and hydropicabortions were significantly higher than in complete hydatidiform moles, whereas no significant differencewas observed between partial hydatidiform moles and hydropic abortions. Bax immunoreactivity wasobserved in cytotrophoblasts, stromal cells and occasionally in syncytiotrophoblasts. No statisticallysignificant difference in Bax immunoexpression total score was observed among various groups. Based onthe results of this study, Bcl-2 immunostaining offers a potential adjunctive diagnostic tool to distinguishcomplete hydatidiform mole from partial hydatidiform mole and hydropic abortion, but not partialhydatidiform mole from hydropic abortion, Bax immunostaining cannot be helpful in this regard.