Geburtshilfe Frauenheilkd 2014; 74 - PO_Endo03_05
DOI: 10.1055/s-0034-1387993

Expression of progesterone receptor membrane component 1 (PGRMC1) in tissues of breast cancer patients

I Wurster 1, C Meisner 2, H Seeger 1, U Vogel 3, AO Mueck 1, T Fehm 4, H Neubauer 4
  • 1Department of Obstetrics and Gynaecology, Eberhard Karls University, Tuebingen, Germany
  • 2Institute for Clinical Epidemiology and Applied Biometry, Eberhard Karls University, Tuebingen, Germany
  • 3Institute of Pathology, Eberhard Karls University, Tuebingen, Germany
  • 4Department of Obstetrics and Gynaecology, Heinrich-Heine University, Duesseldorf, Germany

Progesterone receptor membrane component 1 (PGRMC1) may be important in tumorigenesis and thus may increase the risk for developing breast cancer under certain circumstances e.g. during hormone therapy. The main purpose of this study was to investigate the expression of PGRMC1 in benign and malignant tissues of breast cancer patients.

Matching 'baseline' tissue biopsies of 69 breast cancer patients undergoing neoadjuvant therapy were analyzed by immunohistochemistry for expression levels of PGRMC1 and its phosphorylated version at serine 180. Associations with clinicopathological parameters, e.g. tumour grading and receptor expression, and patient's characteristics e.g. age were calculated.

Every tumour showed expression of PGRMC1 and pPGRMC1 with a very strong expression in the cytoplasm of tumour cells. A much weaker signal was detected in connective tissue surrounding the actual carcinoma tissue (p < 0.001). PGRMC1 and pPGRMC1were co-expressed with estrogen receptors, but not with progesterone receptor. No correlation in expression of PGRMC1 and pPGRMC1 was found with histopathological status, menopausal status, tumour grading or the patient's age. Stratification for age revealed that pPGRMC1 is significantly higher expressed in patients > 70 years than in the age groups 50 – 59 and 60 – 69 years. Expression of PGRMC1 and pPGRMC1 correlated with the expression of certain hormone receptors, especially in the age group of 60 – 69 years.

PGRMC1 is highly expressed in breast tumour tissues and thus may play a decisive role in breast cancer development. Further studies are necessary to reveal how PGRMC1 may be involved in breast carcinogenesis probably triggered by hormone therapy.