One of the main prognostic markers measured in breast tumours is oestrogen
receptor ER status. With the discovery of ER beta, it has been necessary to
re-evaluate ER signalling and the role of ER in breast cancer. preliminary
reports on ER beta signalling suggest it might induce opposite effects to
those of ER alpha. To further understand the biology of breast cancer, the
role each ER plays in disease progression must be established. This review
summarizes the current understanding of ER beta and discusses some of the p
ublished work on the role of ER alpha and ER beta in breast cancer. (C) 200
0 Harcourt Publishers Ltd.