Oestrogen reduces risk of breast cancer: Study

January 14, 2016

"To our surprise, what we have seen is that oestrogen reduces the proportion of breast stem cells which means a mechanism for explaining this better prognosis observed with tumours that express the oestrogen receptor. That is, those tumours expressing the oestrogen receptor are less aggressive, better differentiated and thus have a better prognosis", explained Ms Mar?a Vivanco, leader of the research team.

Ms Vivanco believes that this study presents a new functional aspect of oestrogen, due to its capacity for acting in a different way depending on cellular type.

In the opinion of the CIC bioGUNE researcher, this study "has set out the molecular bases for understanding the direct effect of oestrogen on the proportion of stem cells, whether in healthy or cancerous tissue and the fact that the oestrogen receptor is an excellent prognostic marker". Moreover, this means there is an explanation for a number of clinical observations, for example: the high levels of oestrogen in the blood of postmenopausal patients being associated with less aggressive tumours; the fact that little-differentiated tumours contain more cancerous stem cells, in turn associated with the degree of the tumour, the absence of the oestrogen receptor and low survival rate; and the observed benefit of lactation attributed to a greater differentiation in the breast.

The researchers consider that the new study represents a highly important step, opening new doors to developing tools for the prevention of breast cancer.

Source CIC bioGUNE