Expression of proliferation and apoptotic markers in human placenta during pregnancy.
Trophoblast has unique properties in relation to its wide range of metabolic, endocrine and angiogenic functions. Trophoblastic cells invade endometrium and adjacent myometrium in a way that is imitated by malignant tumours. The aim of the present study was to analyse the expression of markers of proliferation and apoptosis in trophoblastic cells in normal human placenta during pregnancy. A total of 22 placentas, 12 of which were obtained from curettage and induced legal abortion and 10 placentas obtained from normal deliveries or caesarean sections were included in this study. Proliferation markers were strongly expressed in cytotrophoblast in early stages of gestation. In late term placentas, a distinct decrease in expression of these markers was observed. Syncytiotrophoblast was negative for proliferation markers in all placentas. Positive immunostaining for bcl-2, an anti-apoptotic marker, was observed only in syncytiotrophoblastic cells in first-trimester but also in third-trimester placentas. Cytotrophoblast and stromal mesenchymal cells of chorionic villi were negative for bcl-2. Expression of bcl-2 protein in syncytiotrophoblast may be one of the major factors preventing these structures from early cell death, which is indispensable for the maintenance of physiological pregnancy.
Danihel
L'udovít
L
Department of Pathology, School of Medicine, Comenius University, Bratislava, Slovakia. danihel@fmed.uniba.sk
Gomolcák
Pavol
P
Korbel
Miroslav
M
Pruzinec
Jozef
J
Vojtassák
Ján
J
Janík
Peter
P
Babál
Pavel
P
D000328:Adult; D017209:Apoptosis; D015415:Biomarkers / Q000032:analysis; D002455:Cell Division; D002824:Chorionic Villi / Q000378:metabolism; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011263:Pregnancy Trimester, Third; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D014327:Trophoblasts / Q000378:metabolism*; D051028:bcl-2-Associated X Protein
D015415:Biomarkers; D019394:Ki-67 Antigen; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein