Expression of Estrogen Receptors in Relation to Hormone Levels and the Nottingham Prognostic Index.
BACKGROUND
Estrogen hormones have a large impact on both normal development and tumorigenesis of the breast.


METHODS
Breast tissue samples from 49 women undergoing surgery were included. The estrogen receptors (ERα and ERβ), ERα36 and G-coupled estrogen receptor-1 (GPER) were determined in benign and malignant breast tissue.


RESULTS
The ERα36 and ERα mRNA levels were highest in malignant tumors. Stromal ERβ immunostaining in benign tumors was higher than in the paired normal tissue. GPER expression was lowest in benign tumors. In the malignant tumors, the Nottingham Prognostic Index (NPI) correlated positively with stromal GPER and the serum testosterone level. The serum insulin-like growth factor-1 (IGF-1) level correlated negatively with GPER mRNA and glandular ERα.


CONCLUSIONS
The expression of ERα36 is stronger in malignant breast tissue. The strong positive correlation between NPI and GPER in malignant breast stroma indicates an important role for GPER in breast cancer prognosis.
Capio St Göran's Hospital, Stockholm, Sweden Department of Oncology and Pathology, Karolinska Institutet, Stockholm, Sweden Pediatric Endocrinology Unit, Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden mia.fahlen@capiostgoran.se.
Mia
M
Fahlén
Pediatric Endocrinology Unit, Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden Department of Obstetrics and Gynecology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, P.R. China.
Hua
H
Zhang
Capio St Göran's Hospital, Stockholm, Sweden.
Lars
L
Löfgren
Pediatric Endocrinology Unit, Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
Britt
B
Masironi
Department of Oncology and Pathology, Karolinska Institutet, Stockholm, Sweden.
Eva
E
VON Schoultz
Division of Obstetrics and Gynecology, Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
B O
BO
VON Schoultz
Pediatric Endocrinology Unit, Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden.
Lena
L
Sahlin
D000328:Adult; D001940:Breast / Q000737:chemistry*; D001943:Breast Neoplasms / Q000737:chemistry*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D012333:RNA, Messenger / Q000032:analysis; D011960:Receptors, Estrogen / Q000032:analysis* / Q000235:genetics / Q000502:physiology; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000502:physiology; D013739:Testosterone / Q000097:blood*
C109584:GPER1 protein, human; D012333:RNA, Messenger; D011960:Receptors, Estrogen; D043562:Receptors, G-Protein-Coupled; D013739:Testosterone
ERα; ERα36; ERβ; Estrogen receptors; GPER; NPI; breast cancer; premenopausal