Hormone replacement therapies may up breast cancer risk

Women who take hormone replacement therapies in order to reduce the effects of menopausal symptoms may have a higher incidence of breast cancer, researchers have cautioned. Therapies that boost female hormones cause specialised cancer cells to induce growth and spread to other parts of the body.

Salman Hyder said that, “Women’s exposure to natural and synthetic progestin medications that have effects to the progesterone (a steroid hormone) leads to the production of specialised stem cells of cancer in the body.” Both natural and synthetic progestin significantly increased protein expression of CD44 -- a molecule involved in cell proliferation, cell communication and migration.

These rare cells are in small population of cells that act like one normal stem cells, which are self-renewing, create identical copies of them and proliferate exponentially. Further testing showed that the rare subset of cancer cells actually ware enriched by progestins, said the researchers.

Hyder said that, “These cells greatly increase the likelihood of resistance to therapies and the risk for metastasis. Our findings also suggest that clinicians may be able to combat the progestin-dependent tumour growth through immunotherapy."