Study gives hope for new breast cancer medicines

Synthetic hormones called progestins, which are used in HRT and contraceptives, have been linked to the development of the disease by previous studies.

Researchers now claim to have shown that a protein best known for its role in bone metabolism may play a key role in hormone-driven breast cancers.

When people make too much of the protein – RANKL – it can lead to bone loss and osteoporosis. The researchers demonstrated that progestin can also trigger the RANKL protein in breast cells in mice.

In a separate study in the US, researchers found that treating mice with a RANKL inhibitor reduced the incidence of progestin-driven breast cancer in a tumour mouse model.

Both sets of findings were reported online in Nature.

The scientists hope clinical trials will eventually be carried out to test the effect of RANKL-based treatments for human breast cancers.