US scientists have discovered that a faulty enzyme may contribute to the formation of some malignant brain tumours.
Around 70 per cent of people with a type of brain tumour - called a low-grade glioma - have a faulty version of an enzyme called IDH1. The mutation is also found in a significant proportion of patients with acute myeloid leukaemia.
Research led by Agios Pharmaceuticals has now shown that mutations in this enzyme result in unusually high levels of a metabolite called 2-hydroxyglutarate (2HG) in the brain, which has previously been linked to the development of brain cancer.
This study is the first evidence of a role for IDH1 in the development of cancer.
Although the enzyme was known to be faulty in gliomas, scientists did not understand exactly how it could contribute to the disease.
The team, whose findings are published in the journal Nature, analysed samples of tissue taken from malignant gliomas and found that those with faults in the IDH1 enzyme typically had 100 times more 2HG than those with the normal IDH1 enzyme.
It may now be possible to develop a diagnostic test that identifies patients with gliomas that harbour the IDH1 mutation by measuring the levels of 2HG in their brain. Evidence suggests that patients with the mutation tend to do better than those without.
The research could also lead to treatments that block the production of 2HG, which in turn could delay the progression of this kind of brain tumour.
Professor Lew Cantley, director of the Cancer Centre at the Beth Israel Deaconess Medical Centre and founder of Agios Pharmaceuticals, described the work as "groundbreaking".