Study Highlights Potential New Type of Bowel Cancer Treatment
Monday 15 March 2010 - Gene defects that cause some bowel cancers could become the targets for new personalised treatments, according to research published in Cancer Cell.
Around five per cent of bowel cancers are caused by inherited mutations in one of two genes, either MLH1 or MSH2. Cells with these defects can no longer repair DNA damage efficiently, putting them at risk of becoming cancerous. But these defects are a ‘double agent’, a potentially fatal weakness of the cancer cell that new treatments could be developed to exploit.
A team from the Breakthrough Breast Cancer Centre at the ICR found that blocking a second DNA repair mechanism in these cells – DNA polymerases – cripples them. The cells are unable to repair DNA damage and ultimately die. The scientists propose that targeting cells carrying one of these mutations with a drug that blocks this second part of DNA repair could be an effective treatment for MLH1- or MSH2-linked cancers. Normal, healthy cells can still rely on their functioning MLH1 or MSH2 genes to repair themselves and so are left relatively unscathed. A treatment based on this mechanism would potentially therefore carry fewer side-effects.
Study author Dr Chris Lord, from the ICR, said: “We’re trying to develop new ways of treating bowel cancer that are based on tailoring the type of treatment to each individual patient. By looking at the patients with defects in two genes called MSH2 and MLH1 we hope to eventually develop new drugs that kill these cancer cells without affecting normal cells.
