Expression of Progesterone and Androgen Receptors in the Breast of Premenopausal Women, Considering Menstrual Phase.

BACKGROUND: Progesterone and androgens are important for normal development and tumorigenesis of the breast. PATIENTS AND METHODS: Breast tissue samples from 49 premenopausal women were obtained. The progesterone receptors (PRA, PRB, PGRMC1 and PGRMC2) and the androgen receptor (AR) were determined in malignant and benign breast tumors and control tissues. RESULTS: The PRB and AR mRNA levels were highest in tumors. PGRMC1 and PGRMC2 mRNA levels were higher in malignant tumors compared to their paired normal tissues. PRA protein showed most immunostaining in benign tumors. PRB immunostaining varied according to menstrual phase. AR immunostaining was highest in the glands of malignant tumors. CONCLUSION: Progesterone and androgen receptors are differently regulated in tumors compared to normal breast tissues. A malignant breast tumor could appear PR-negative if collected in the luteal phase, but positive in the follicular phase. This finding may have clinical implications.

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. MATERIALS AND METHODS: Breast tissue samples from 49 women undergoing surgery were included. The estrogen receptors (ERα and ERß), 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 ERß 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. CONCLUSION: 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.

Hormone replacement therapy after breast cancer: 10 year follow up of the Stockholm randomised trial.

BACKGROUND: The management of hormonal deficiency symptoms in breast cancer survivors is an unsolved problem. While hormone replacement therapy (HRT) may increase the risk of breast cancer in healthy women, its effects on recurrence is unclear. Observational studies have suggested decreased recurrence rates from HRT. The few clinical trials in this field have all been closed preterm. METHODS: The Stockholm trial was started in 1997 and designed to minimise the dose of progestogen in the HRT arm. Disease-free women with a history of breast cancer were randomised to HRT (n=188) or no HRT (n=190). The trial was stopped in 2003 when another Swedish study (HABITS, the Hormonal Replacement After Breast Cancer - Is it Safe?) reported increased recurrence. However the Stockholm material showed no excess risk after 4 years of follow-up. A long term follow-up has now been performed. FINDINGS: After 10.8 years of follow-up, there was no difference in new breast cancer events: 60 in the HRT group versus 48 among controls (hazard ratio (HR)=1.3; 95% confidence interval (CI)=0.9-1.9). Among women on HRT, 11 had local recurrence and 12 distant metastases versus 15 and 12 for the controls. There were 14 contra-lateral breast cancers in the HRT group and four in the control group (HR=3.6; 95% CI=1.2-10.9; p=0.013). No differences in mortality or new primary malignancies were found. INTERPRETATION: The number of new events did not differ significantly between groups, in contrast to previous reports. The increased recurrence in HABITS has been attributed to higher progestogen exposure. As both trials were prematurely closed, data do not allow firm conclusions. Both studies found no increased mortality from breast cancer or other causes from HRT. Current guidelines typically consider HRT contraindicated in breast cancer survivors. Findings suggest that, in some women symptom relief may outweigh the potential risks of HRT.

Megestrol acetate may stimulate the production of insulin-like growth factor 1 in breast tissues of women with breast cancer.

BACKGROUND: In women with breast cancer who were treated with either continuous tamoxifen alone or sequential tamoxifen followed by megestrol acetate (MA), we demonstrated significant positive associations between the breast tumor estrogen receptor (ER) and an increase in serum sex hormone-binding globulin (SHBG) during tamoxifen treatment. We interpreted this as "ER uniformity" in different tissues, e.g., breast, liver. No other associations with ER were found. In the same study, the breast tumor progesterone receptor (PR) was determined. Our aim was to see if there were any associations between PR and endocrine changes during MA treatment. METHODS: The breast tumor PR before treatment and serum insulin-like growth factor I (∂IGF-1), steroids, steroid-binding proteins, and insulin before and during treatment were measured in 17 postmenopausal women with breast cancer who were treated sequentially with tamoxifen 40 mg/day followed by MA 160 mg/day in alternating 3-month periods. RESULTS: During MA treatment periods, the levels of IGF-1 and insulin increased significantly, whereas the levels of androgens, SHBG, corticosteroid-binding globulin, and cortisol decreased significantly. Significant positive correlations were found between the PR content and increments in ∂IGF-1 but not between PR and any other endocrine change. CONCLUSIONS: PR expression in human liver is very weak, but malignant and normal breast tissues secrete considerable amounts of growth hormone and IGF-1 in vitro and in vivo. This activity is stimulated by progestogens. The association between PR and ∂IGF-1 may therefore reflect a direct PR-mediated action of MA on malignant and normal human breast tissues in vivo.