A groundbreaking new approach for treating triple-negative breast cancer (TNBC) is moving forward, thanks to discoveries from Dr. Donald McDonnell’s lab at Duke University. Traditionally, hormone therapies have only been considered effective for estrogen receptor-positive (ER+) cancers, but McDonnell’s research suggests that estrogen modulation could also impact TNBC. The team’s recent study, published in Science Advances, challenges the conventional understanding of TNBC by demonstrating that estrogen can stimulate the growth of cancers traditionally thought to be hormone-insensitive, including TNBC, by affecting immune cells in the tumor microenvironment.