Lab study ‘sheds new light’ on BRCA-linked breast cancer

An osteoporosis drug has been found to target a set of molecular signals that could help prevent breast cancers in women at risk of the disease, according to Australian scientists. 

The lab-based findings need confirming in clinical studies, but could offer a new way to prevent breast cancers linked to inherited faults in the BRCA1 gene.

The research team, based at the Walter and Eliza Hall Institute, used cells, donated by women with the faulty gene, that gave rise to breast cancer in lab models.

The cells grew rapidly and their DNA was susceptible to damage – both key factors in allowing them to become cancer cells, according to the Nature Medicine study.

Further analysis showed that these pre-cancerous cells could be identified by a marker called RANK.

The molecule controls a set of signals important for cell growth, which can be targeted with a drug developed for osteoporosis.

The Australian team found that the drug, called denosumab, slowed the development of breast cancer in lab conditions.

Professor Geoff Lindeman, from The Royal Melbourne Hospital and part of the research team, called the findings ‘important’, and said they could offer a way to prevent breast cancers in high risk women.

“We think this strategy could delay or prevent breast cancer in women with an inherited BRCA1 gene mutation,” he said.

Women with faults in the BRCA1 gene are at a higher risk of breast and ovarian cancers.

Those with the faults can choose to have breast tissue or their ovaries removed to reduce their chances of developing the diseases.

Dr Jason Carroll, a Cancer Research UK expert in breast cancer genetics, echoed the potential of the results.

“These findings shed new light on the molecular signals that may lead to breast cancer in people with inherited faults in their BRCA1 gene,” he said. 

“While the data are limited to laboratory conditions, the study reveals a potential new opportunity to prevent some cases of breast cancer in women at high risk using existing drugs.” 

Carroll added that further clinical research will be needed to help test this potential, especially as the drugs have known side effects.

“But when weighed against the potential for delaying cancer progression in high risk women,” he said, “it is a worthy area for future work.”   

Lindeman said that a clinical trial had already begun to investigate the drug further.