Role of GPR30 in endometrial pathology after tamoxifen for breast cancer.
OBJECTIVE
This study was undertaken to evaluate the potential role of G-protein-coupled estrogen receptor in endometrial pathology associated with tamoxifen treatment of breast cancer patients.


METHODS
We investigated whether G-protein-coupled estrogen receptor plays a role in mediating proliferating effect of tamoxifen in endometrial carcinoma cells. These results were compared with the G-protein-coupled estrogen receptor expression pattern in endometrial tissue from a cohort of 95 breast cancer patients, who received tamoxifen or another adjuvant therapy.


RESULTS
In vitro tamoxifen significantly stimulated the mitogen-activated protein kinase phosphorylation and cell proliferation of endometrial cell lines via G-protein-coupled estrogen receptor. In vivo, there was a significant correlation between G-protein-coupled estrogen receptor expression and the tamoxifen-induced endometrial pathology (P = .006). Moreover, G-protein-coupled estrogen receptor positivity was predictive of an earlier development of symptoms, such as bleeding or suspect endometrial thickness, induced by tamoxifen therapy (P = .019).


CONCLUSIONS
G-protein-coupled estrogen receptor plays an important role in tamoxifen-induced endometrial abnormalities.
Department of Obstetrics and Gynecology, Otto-von-Guericke University, Magdeburg, Germany.
Tanja
T
Ignatov
Holm
H
Eggemann
Andrzej
A
Semczuk
Bobbie
B
Smith
Joachim
J
Bischoff
Albert
A
Roessner
Serban D
SD
Costa
Thomas
T
Kalinski
Atanas
A
Ignatov
D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology; D049109:Cell Proliferation / Q000187:drug effects; D016889:Endometrial Neoplasms / Q000139:chemically induced* / Q000473:pathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D066298:In Vitro Techniques; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism*; D012016:Reference Values; D012680:Sensitivity and Specificity; D013629:Tamoxifen / Q000009:adverse effects* / Q000494:pharmacology / Q000627:therapeutic use; D014407:Tumor Cells, Cultured / Q000187:drug effects
D043562:Receptors, G-Protein-Coupled; D013629:Tamoxifen