Comparison of cell cycle regulatory gene mRNA in three different types of human trophoblasts and effect of transforming growth factor.
OBJECTIVE
Identifying the factors responsible for reducing the proliferation, syncytialization, and invasiveness of trophoblast tissues, as seen with preeclampsia, intrauterine growth restriction, and spontaneous miscarriage, is a current challenge in reproductive biology. These factors, transforming growth factor (TGF)-beta as an example, can work by altering trophoblast differentiation or proliferation. We therefore investigated and compared specific markers of trophoblast proliferation and differentiation in three commonly used trophoblast tissue cell models, and also investigated the influence of TGF-beta on these markers.


METHODS
In this study, we isolated human trophoblasts from first trimester and term placentas, and additionally used human choriocarcinoma cells (JEG-3). Baseline values of human chorionic gonadotropin (hCG) secretion and relative mRNA levels of cell cycle regulators (cyclin E, p21, p27, and p57) were investigated for each cell type. We also investigated the influence of TGF-beta on these parameters.


RESULTS
Quantitative and longitudinal production of hCG differed between the three cell types. Significantly different amounts of cyclin E, p21, p27, and p57 mRNA were demonstrated within each cell type, as well as between all the cell types, throughout the culture time period. Each trophoblast type demonstrated a reduction of hCG secretion in response to TGF-beta. TGF-beta did not show a consistent effect on the cell cycle mRNA of any of the cell types.


CONCLUSIONS
We were able to characterize and compare the differential production of hCG, as well as the differential expression of cell cycle-associated mRNA of early trophoblasts, term trophoblasts, and choriocarcinoma cells. The production of hCG was altered by TGF-beta, although mRNA levels were not markedly altered by TGF-beta.
Richard
Craig A H
CA
Department of Obstetrics, Gynecology, and Reproductive Sciences, Magee-Women's Research Institute, Pittsburgh, Pennsylvania, USA. crichard@su.edu
Jones
Jaqueline M
JM
DeLoia
Julie A
JA
D018797:Cell Cycle Proteins / Q000096:biosynthesis / Q000235:genetics; D045744:Cell Line, Tumor; D002822:Choriocarcinoma; D006063:Chorionic Gonadotropin / Q000502:physiology*; D005260:Female; D018816:Genes, cdc; D006801:Humans; D010920:Placenta / Q000166:cytology; D011247:Pregnancy; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016212:Transforming Growth Factor beta / Q000494:pharmacology*; D014327:Trophoblasts / Q000187:drug effects / Q000502:physiology*
D018797:Cell Cycle Proteins; D006063:Chorionic Gonadotropin; D012333:RNA, Messenger; D016212:Transforming Growth Factor beta