London - Breast cancer could be prevented with a drug that is already used to tackle brittle bone disease, scientists claim.
Women with the faulty BRCA1 gene, such as actress Angelina Jolie, are up to 87 per cent more likely to develop tumours. Many resort to having their breasts and ovaries removed as a preventative measure.
But now Australian researchers say the osteoporosis drug denosumab was so effective in tests they are ‘on the path to the Holy Grail’ – finding a medicine to stop breast cancer forming and so save women from drastic surgery.
Professor Jane Visvader, co-author of the study, said: ‘We have been able to pinpoint the precise cells that are the culprits in cancer formation. It is very exciting to think that we may be on the path to the ‘Holy Grail’ of cancer research, devising a way to prevent this type of breast cancer in women at high genetic risk.’
Miss Jolie had a double mastectomy in 2013, aged 37, after learning she was at 87 per cent risk of developing breast cancer, then had her ovaries removed last year after tests revealed that they might become cancerous.
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Her grandmother and mother were both killed by ovarian cancer and her aunt, who carried the same defective gene, died from breast cancer three months after Miss Jolie’s initial surgery.
Because denosumab has already been tested on people, an effective treatment could be produced much sooner, unlike drugs that have to go through lengthy safety trials.
Researchers at the Walter and Eliza Hall lnstitute in Melbourne said using it on pre-cancerous breast tissue cells showed promise at preventing tumours. If the findings are confirmed in other studies, it could be a non-surgical alternative to stop breast cancer in women with a higher risk of the disease.
The study was published in the journal Nature Medicine. University researcher Linda Nolan said they had identified cells more likely to become cancerous – and the drug stopped that happening.
She said: ‘These cells proliferated rapidly, and were susceptible to damage to their DNA -– both factors that help them transition towards cancer. We were excited to discover that these pre-cancerous cells could be identified by a marker protein called Rank.’
The research said Rank cells have ‘a molecular signature similar to that of basal-like breast cancer’. Professor Geoff Lindeman, an oncologist at The Royal Melbourne Hospital, said the discovery is an important breakthrough, since a therapy to stop the relevant chemical change exists.
‘An inhibitor called denosumab is already used in the clinic to treat osteoporosis and breast cancer that has spread to the bone,’ he said. ‘We therefore investigated what effect Rank inhibition had on the cancer precursor cells in BRCA1-mutant breast tissue.’
Researchers found it switched off cell growth in breast tissue from women with a faulty BRCA1 gene and it also cut breast cancer development within laboratory models.
Professor Lindeman said: ‘We think this strategy could delay or prevent breast cancer in women with an inherited BRCA1 gene mutation.
A clinical trial has already begun to investigate this further. This is potentially a very important discovery for women who carry a faulty BRCA1 gene.’
Dr Christopher Lord, reader in cancer genomics and therapeutics at the Institute of Cancer Research in London, said: ‘This research paper is interesting as it might suggest how certain types of breast cancer develop.’
He said trials would be needed on possible harmful effects of long-term denosumab use, compared to its potential benefits in cancer treatment, but added: ‘This is the first step in the right direction.’
Another research team in Austria led by geneticist Josef Penninger earlier discovered that denosumab also stopped mice with BRCA1 developing breast cancer.
Daily Mail