Irish scientists have found a new way to protect normal healthy cells from the harmful effects of irradiation or chemotherapy used in treating cancers and yet allow tumour cells to die. BioResearch Ireland, a State-funded agency, announced yesterday that it could lead to new therapies within 10 years.
Scientists at its facility in Trinity College Dublin have discovered that a specific inhibitor of an enzyme in the body - known as a monoamine oxidase (MAO) inhibitor - has this selective ability to eliminate bad cells only, which could have "very positive implications for cancer treatment".
MAO inhibitors are already in use as drugs in the treatment of Parkinson's disease and depression. But BioResearch Ireland declined to say which specific inhibitor it found to be so effective in this novel application, pending full patent protection of its discovery.
The inhibitor, code-named GPX-325, has been shown to be effective in protecting normal cells against the "cell-killing" effects of three classes of chemotherapeutic agents. This means it has significant potential to ensure cancer treatment is focused primarily on the tumour-generating cells. The results were confirmed in tests using laboratory cultures of normal and human tumour cells.
In addition, it could facilitate more aggressive forms of treatment, as it is likely to ensure that debilitating side-effects, particularly damage to normal tissue in close proximity to cells forming tumours, are reduced.
"We think our discovery is very, very exciting . . . We cannot identify the compound because the patent has not been fully examined yet," said Dr Margaret Woods, of the National Centre for Pharmaceutical Biotechnology in Trinity, which made the discovery.
"The ability of MAO inhibitors to protect/rescue normal cells from the toxic side-effects of irradiation or the administration of chemotherapeutic agents may have very positive implications for the treatment of cancer," said Mr Seamus O'Hara, the business development manager at BioResearch Ireland.
Together with the administration of GPX-325, higher and potentially more cytotoxic doses of either radiation or chemo therapeutics aimed at tumour growths may soon be administered to patients, where surrounding normal cells will remain relatively undamaged, he added.
BioResearch Ireland has filed an international patent application to cover the use of MAO inhibitors as "cytoprotective agents", and signed an agreement with a US company, Gem Pharmaceuticals, with a view to it evaluating the findings. The company has a year to decide on a licence purchase option which would allow it to develop a drug for use in cancer treatment, and to determine in what form it should be taken, orally or intravenously.
Because the drug has already been cleared for human use - albeit to treat other conditions - it will not need the usual stringent testing before it is available to doctors, a process which can take up to 15 years. Nonetheless, as it is likely to be used in "combination therapies", i.e. with radiation/chemotherapy, the possibility of side-effects from its new application will have to be investigated.
BioResearch Ireland was established in 1988 as a partnership between Irish universities. It aims to commercialise developments in biotechnology research.
