The role of oestrogen receptor β in invasive breast cancer

Abstract

Background

The presence of estrogen receptor (ER) in breast cancer cell is a good prognostic factor. It is also a predictive factor used in hormonal therapy.

Aim

To evaluate the expression of oestrogen receptors α and β (ERα and ERβ) in the neoplastic tissues of patients with invasive breast cancer and to determine whether ERβ expression may be correlated with some clinical parameters and biological markers.

Materials/Methods

Paraffin embedded tissues from 67 patients with breast cancer were used in this study. Monoclonal antibodies against α oestrogen receptors, progesterone receptors (DakoCytomation) and polyclonal antibodies against β oestrogen receptors (CHEMICON) were used. The EnVision detection system was applied.

Results

Expression of ERα was demonstrated in 57% of all patients, while in patients over 50 years it was higher – 71%. Expression of ERβ was demonstrated in 48% of patients and this percentage was not dependent on the age of the patients. In tumours expressing ERβ, expression of p53 and Ki-67 was less common. In addition, these tumours were of a lower grade of malignancy.

Conclusions

Our results demonstrate a negative correlation between the expression of ERβ and the expression of p53 and Ki-67. The expression of ERβ may be a good prognostic indicator.