“Estrogen promotes the growth of tumors such as breast cancer”… Clinical anti-cancer plan against estrogen

Yonhap News

Estrogen, a female hormone, has been found to promote the growth of breast and other cancers by weakening immune cells that help suppress tumors.

The research team expects that anti-estrogen drugs can be applied in anti-cancer treatment.

On the 28th (local time), Professor Donald Macdonald’s team at the Duke University Cancer Institute published in the scientific journal Science Advances, the results of tests on mouse models of breast cancer and melanoma showed that estrogen weakens the ability of the immune system to attack tumors and that the effect of immunotherapy was also found to be reduced.

Breast cancer is one of the most common cancers in women. Triple-negative breast cancer, which lacks estrogen receptor (ER), progesterone receptor (PR), and epidermal growth factor receptor 2 (HER2), metastasizes to the brain and lungs more often than other breast cancers, and is live for 5 years. rate of only 12%.

Professor McDonell said, “Treatment of triple-negative breast cancer has improved significantly with the advent of immunotherapy, but in many cases, the outcome is not good. The main goal of this research is to develop a method to increase anti-cancer activity. of immunotherapy.”

In this study, the research team focused on eosinophils, a type of white blood cell that is commonly activated in allergic reactions and inflammatory diseases.

It has recently been discovered that eosinophils play an important role in tumors, and tumor-associated eosinophilia (TATE) has been shown to be associated with a better prognosis in cancer patients, including colon, esophageal cancer, stomach cancer, oral cancer, melanoma, and liver cancer, the research team explained.

Experiments in mouse models of breast cancer and melanoma showed that estrogen reduced the number of eosinophils and tumor-associated eosinophilia (TATE), thereby promoting the growth of estrogen receptor-negative breast cancer tumors and non-estrogen receptor-negative melanoma tumors. dependent on estrogen receptors for growth. .

On the other hand, it was found that in mice given anti-estrogen drugs, estrogen receptor signaling was suppressed, increasing the effectiveness of immunotherapy and slowing tumor growth.

“These results show that estrogen plays an important role in the function of eosinophils and the regulation of TATE,” said Professor McDonell. He said, “Based on these results, we are planning a clinical trial of the drug -anti-estrogen called ‘lasofoxifene’ for triple-negative breast cancer patients.