A gene that causes one in 20 cases of prostate cancer has been identified

    7 July 2016

    Researchers have discovered a gene that could be responsible for five per cent of prostate cancer cases, according to a study published in the New England Journal of Medicine.

    The study, which involved 692 volunteers with advanced prostate cancer, could lead to a cheap and reliable saliva test to detect the disease, potentially improving survival rates.

    The Institute of Cancer Research in London found that five per cent of men with advanced prostate cancer carry BRCA2, and estimate that 0.3 per cent of all men carry the faulty gene.

    The researchers say that those found to carry the gene could benefit from PARP inhibitors, a new class of drug which specifically targets DNA.

    Professor Johann de Bono, an experimental cancer medicine expert at the institute, said: ‘Our study has shown that a significant proportion of men with advanced prostate cancer are born with DNA repair mutations — and this could have important implications for patients.

    ‘Genetic testing for these mutations could identify men with advanced prostate cancer who may benefit from precision treatment.

    ‘We could offer these men drugs such as PARP inhibitors, which are effective in patients with certain DNA repair mutations and are showing important anti-tumour activity in ongoing clinical trials.

    ‘Where we find BRCA2 mutations, we could also offer genetic testing and counselling to relatives of the patient to consider how we can reduce their cancer risk.

    ‘We also need to establish the impact of having DNA repair defects on survival in men with prostate cancer, and whether we can predict who will develop severe disease, so we can design new treatment strategies to cure this disease.’

    Instant analysis
    This study has the potential to change the future treatment of prostate cancers, but at present has limited clinical application. More research needs to be done on the link between the gene mutations and the cancers themselves, and how realistic it is for this to be exploited clinically in a positive way without resulting in over-screening — that is, tests that do not target well the conditions they are screening for (for example PSA testing for prostate cancer) and result in unnecessary invasive procedures.
    Research score: 3/5