Discovered in CIC bioGUNE that estrogen reduces the aggressiveness of breast cancer

2011/03/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Biokimika
• Osasuna
• Medikuntza

A team of researchers at CIC bioGUNE has found that estrogen could improve the prognosis of breast cancer. In their work they have shown that estrogen is capable of reducing the number of stem cells of breast cancer. This could explain that in these cases the tumors have a lower aggressiveness and therefore a better prognosis. The work has been published in the journal Breast Cancer Research and Treatment.

Cancer treatments are often designed to reduce tumor mass. That is, they are able to kill most of the cell mass of the tumor, but cancer stem cells are more resistant to conventional treatments, such as chemotherapy and radiation therapy. Therefore, for a more effective and definitive recovery of cancer, it is necessary to find ways to remove stem cells from cancer. In fact, in recent years it has been observed that cancer stem cells are related to the aggressiveness of the tumor: the greater the proportion of breast cancer stem cells, the more aggressive the cancer is.

Estrogen is a complex hormone, essential for the development and proper functioning of the breast, but, on the other hand, it causes the proliferation of cancer cells after the appearance of the breast tumor. However, until now little was known the influence of estrogen on the tumor initiating cells.

The research carried out at CIC bioGUNE has partially clarified this influence. "Without waiting, we've seen estrogen reduce the proportion of stem cells in the chest. What's more, tumors that express the estrogen receptor are less aggressive, are better differentiated and, therefore, have better prognosis - explains María Vivanco, head of the research group. Perhaps that is why the tumors that express the estrogen receptor have a better prognosis." Therefore, it considers that the estrogen receptor can be a "probative indicator of cancer."