Expression of mTOR and downstream signalling components in the JEG-3 and BeWo human placental choriocarcinoma cell lines.
Emerging data suggest that nutritional status and body weight are related to reproductive function, and nutrient imbalances during pregnancy lead to changes in the expression of fetal genes. Recent studies show that the mTOR acts as a placental growth signalling sensor and its expression is down-regulated in intrauterine growth restriction. To date, very little is known about the expression of this signalling pathway in choriocarcinoma, one of the most lethal germ cell cancers. In this study, cultures of fusigenic (BeWo) and non-fusigenic (JEG-3) human choriocarcinoma cell lines were used to investigate the expression of mTOR and its downstream signalling components. The effects of an inducer of syncytialisation (forskolin) on mTOR, eIF4E binding proteins (4EBPs) and ribosomal protein S6 kinases (S6Ks) in BeWo cells were also assessed. RT-PCR studies revealed that mTOR, 4EBP and S6Ks are expressed at mRNA level in both JEG-3 and BeWo cells. Semi-quantitative RT-PCR analysis revealed that in early stages of syncytialisation (50 microM forskolin for 48 h), the expression of mTOR and 4EBP was down-regulated when compared to unstimulated cells. In fully syncytialised cells (50 microM forskolin for 72 h) the expression of both genes was similar to basal levels. Interestingly, the phosphorylation (Ser371, Thr389) status of p70S6K remained unaltered upon forskolin treatment. These data validate BeWo cells as an experimental model to study the effects of forskolin-induced syncytialisation on mTOR signalling.
Mparmpakas
Dionisis
D
Centre for Cell Chromosome Biology, Biosciences, School of Health Sciences and Social Care, Brunel University, Uxbridge UB8 3PH, UK.
Zachariades
Elena
E
Foster
Helen
H
Kara
Anjeli
A
Harvey
Amanda
A
Goumenou
Anastasia
A
Karteris
Emmanouil
E
D045744:Cell Line, Tumor; D002822:Choriocarcinoma / Q000235:genetics* / Q000378:metabolism; D005576:Colforsin / Q000494:pharmacology; D039561:Eukaryotic Initiation Factor-4E / Q000235:genetics / Q000378:metabolism; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics* / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D010920:Placenta / Q000166:cytology* / Q000473:pathology; D011247:Pregnancy; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D019893:Ribosomal Protein S6 Kinases / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D058570:TOR Serine-Threonine Kinases; D014594:Uterine Neoplasms / Q000235:genetics* / Q000378:metabolism
D039561:Eukaryotic Initiation Factor-4E; D047908:Intracellular Signaling Peptides and Proteins; D012333:RNA, Messenger; D005576:Colforsin; C546842:MTOR protein, human; D017346:Protein Serine-Threonine Kinases; D019893:Ribosomal Protein S6 Kinases; D058570:TOR Serine-Threonine Kinases