A cheap diabetes drug, metformin, could reduce the risk of prostate cancer by up to 35%, according to new research. The medication, which has been used for almost a century to treat type 2 diabetes, is being investigated for its potential anti-cancer properties.
Scientists believe metformin works by blocking the supply of glucose that cancer cells need to grow and multiply, as well as inhibiting enzymes involved in cancer cell growth. A recent study published in the journal Carcinogenesis found that combining metformin with a class of anti-cancer drugs reduced breast cancer cell growth by up to 76%.
However, experts urge caution. Dr Jeremy Blaydes, a cancer cell biologist from the University of Southampton, said: 'More work is still needed — we need the outcomes of more studies before we can think about recruiting patients into large human trials.' Breast Cancer Now echoed this, stating there is not enough evidence to show metformin works.
Despite the promising findings, metformin is rarely prescribed for cancer on the NHS. One GP, Lisa McGrath, who has stage four breast cancer, uses metformin alongside her mainstream treatment and believes it has helped keep her cancer at bay. She said: 'As a GP you aren't allowed to recommend it — if patients asked about metformin, I could tell them to ask their oncologist about it, or say I believe it has a benefit, but that's all.'
The drug's lack of use in cancer treatment may be due to financial disincentives for pharmaceutical companies to investigate its potential, as metformin is cheap and off-patent. More research is needed before it can be widely adopted for cancer therapy.
