University of Iowa researchers have discovered a gene that plays a linchpin role in the ability of breast cancer cells to respond to estrogen. The finding may lead to improved therapies for hormone-responsive breast cancers and may explain differences in the effectiveness of current treatments.Estrogen causes hormone-responsive breast cancer cells to grow and divide by interacting with estrogen receptors made by cancer cells. Interfering with estrogen signaling is the basis of two common breast cancer therapies -- tamoxifen, which blocks estrogen’s interaction with a primary estrogen receptor called ER-alpha, and aromatase inhibitors that reduce the amount of estrogen the body makes and therefore affect any pathway that uses estrogen.
