Potential New Treatments For Hormone-Therapy-Related Breast Cancers
"We identified a specific cell membrane protein that blocks cell death in breast cancer cells and allows these cells to grow in response to hormone replacement therapy," said Hyder. "Others have observed an over-abundance of these proteins in a population of breast cancer cells which may explain increased risk of breast cancer in women who consume hormone replacement therapy. Therapies could be developed that would block the activity of these cell membrane proteins, which would make cancer cells more likely to die. The membrane protein is known as PGRMC1."
The proteins identified by Hyder and his colleagues were affected by progestin, one of the hormones given to women to stave off the effects of menopause. Progestin is a synthetic chemical which mimics the hormone progesterone. In hormone replacement therapy, doctors prescribe progestin along with synthetic replicas of the hormone, estrogen.
"Every progestin type that we have tested has negative effects," said Hyder. "A growing body of evidence suggests women should be wary before taking progestin. However, if women take only synthetic estrogens, such as estradiol, it leads to a higher risk of uterine cancer. Hence, the two must be taken together, but even then they seem to still increase cancer risks in post-menopausal women."