G protein-coupled estrogen receptor (GPER) expression in endometrial adenocarcinoma and effect of agonist G-1 on growth of endometrial adenocarcinoma cell lines.
The G protein-coupled estrogen receptor (GPER, GPR30) is suggested to be involved in non-nuclear estrogen signaling and is expressed in a variety of hormone dependent cancer entities. This study was performed to further elucidate the role of this receptor in endometrial adenocarcinoma. We first analyzed GPER expression at the mRNA level in 88 endometrial cancer or normal endometrial tissue samples and compared it to those of nuclear steroid hormone receptors. GPER transcript levels were found to be about 6-fold reduced, but still present in endometrial cancer. Expression of this receptor was decreased in all grading subgroups when compared to pre- or postmenopausal endometrium. GPER mRNA expression was associated with PR mRNA levels (Spearman's rho 0.4610, p<0.001). We then tested the effect of the GPER ligand G-1 on growth of three endometrial cancer cell lines with different GPER expression. GPER protein levels were highest in RL95-2 cells, moderate in HEC-1A cells and not detectable in HEC-1B cells. The moderate expression level in HEC-1A cells was similar to average tumor tissue expression. Treatment with G-1 significantly inhibited growth of the GPER-positive cell lines RL95-2 and HEC-1A in a dose-dependent manner, whereas the GPER-negative line HEC-1B was not affected. Though GPER transcript levels were found to be reduced in endometrial cancer, our in vitro data suggest that moderate GPER expression might be sufficient to mediate growth-inhibitory effects triggered by its agonist G-1.
Department of Obstetrics and Gynecology, University Medical Center Regensburg, Regensburg, Germany; Second Department of Gynecology, Medical University of Lublin, Poland.
Maciej
M
Skrzypczak
Susanne
S
Schüler
Claus
C
Lattrich
Atanas
A
Ignatov
Olaf
O
Ortmann
Oliver
O
Treeck
D000230:Adenocarcinoma / Q000473:pathology*; D000328:Adult; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D003517:Cyclopentanes / Q000494:pharmacology*; D016889:Endometrial Neoplasms / Q000473:pathology*; D004717:Endometrium / Q000187:drug effects / Q000378:metabolism; D047628:Estrogen Receptor alpha / Q000235:genetics; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics; D008875:Middle Aged; D051059:PTEN Phosphohydrolase / Q000235:genetics; D011804:Quinolines / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011960:Receptors, Estrogen / Q000819:agonists* / Q000235:genetics*; D043562:Receptors, G-Protein-Coupled / Q000819:agonists* / Q000235:genetics*; D011980:Receptors, Progesterone / Q000235:genetics
C517943:1-(4-(6-bromobenzo(1,3)dioxol-5-yl)-3a,4,5,9b-tetrahydro-3H-cyclopenta(c)quinolin-8-yl)ethanone; D003517:Cyclopentanes; D047628:Estrogen Receptor alpha; C109584:GPER1 protein, human; D008565:Membrane Proteins; D011804:Quinolines; D012333:RNA, Messenger; D011960:Receptors, Estrogen; D043562:Receptors, G-Protein-Coupled; D011980:Receptors, Progesterone; C446603:TPTE protein, human; D051059:PTEN Phosphohydrolase
Endometrial adenocarcinoma; G protein-coupled estrogen receptor; G-1; GPER