New, less toxic treatment for skin cancer being developed
Release Date 28 September 2005
A new, less toxic way to treat malignant melanoma (skin cancer) is being developed by medicinal chemists at the University of Reading. They have produced a range of prodrugs: compounds that offer the potential to be converted to toxic molecules only within the vicinity of tumours. These prodrugs aim to reduce the toxicity of treatment. The research was showcased on Monday 26 September at the British Pharmaceutical Conference in Manchester. Malignant melanoma is a highly aggressive skin cancer. If caught early, it can be treated surgically, but in many cases the disease has spread by the time it is diagnosed and chemotherapy is needed. The problem with current cancer chemotherapy drugs is their tendency to be toxic to healthy cells in the body, producing severe side effects. The new drug treatment under development specifically targets the tumour. It does this by taking advantage of an enzyme (tyrosinase) that is generally present at increased levels in melanoma cells compared with normal melanocytes, and is virtually absent from other cells. Dr Helen Osborn, from the University's School of Pharmacy, explained: "Tyrosinase is not in itself a problem. But its presence in melanoma provides us with a tool that we can use to convert a non-toxic prodrug into a toxic agent." Dr Osborn says that, as well as reducing toxicity, the prodrug approach has the advantage of delivering high concentrations of drug to the tumour, which should discourage development of resistant tumours. "Often, only a small amount of drug reaches the tumour and any surviving cells can develop resistance," she says. Dr Osborn says that no compound is yet ready for clinical testing, as further work is needed to improve the prodrug selectivity for melanoma cells. "We want it to be very toxic in tyrosinase-containing cells and completely non-toxic in cells that do not contain tyrosinase," she explains. end This press release was issued by BPC 2005 (British Pharmaceutical Conference). For further information please contact the press office on: • 020 7572 2335/6 (pre and post conference) • 0161 832 2018, 0161 832 1086, 0161 832 1089 or 0161 832 2009 (26 – 28 September) • 07971 022297 or 07899 792095 (available at all times) Notes for editors 1. The new School of Pharmacy at the University of Reading has its first intake of undergraduate students in October 2005. Dr Osborn previously worked in the University's School of Chemistry but she is now director of pharmaceutical chemistry in the School of Pharmacy, which is where the tyrosinase research will continue. 2. The British Pharmaceutical Conference was held at Manchester International Convention Centre from Monday 26 September to Wednesday 28 September 2005. The conference theme was A common vision for health: Linking science with practice.