Discovery by Australian researchers leads to test for aggressive cancers 26 November 2009 A discovery by Australian researchers is being hailed as the first major breakthrough in some aggressive types of cancers in 30 years. The prestigious international journal, Nature Biotechology, has just published research by a team from the Children’s Medical Research Institute in Sydney. The Australian scientists are developing a blood test which will detect 15 per cent of all cancers and may help in the diagnosis and treatment of some of the most aggressive forms of the disease – particularly bone, brain and connective tissue cancers, as well as some breast and lung cancers. The test should be possible with a normal blood test specimen. The Australian scientists have been looking at telomeres – the protective DNA caps at the end of chromosomes – that wear away each time a normal cell divides. When telomeres become too short, the cell dies of old age. This is not the case with cancer cells, however, which use two different techniques to prevent their telomeres from shortening, thereby allowing them to multiply indefinitely. Around 85 per cent of cancers rebuild their telomeres with an enzyme called telomerase; the other 15 per cent use a mechanism called ALT (alternative lengthening of telomeres). Both mechanisms are prime targets for the development of new anti-cancer treatments. Dr Jeremy Henson from the Institute team discovered that cancer cells using ALT produce tiny circles of DNA, and that the number of circles relates to how strongly the mechanism is switched on. This provides a sensitive, rapid indicator of ALT activity, which in turn makes it quicker to screen for drugs which can switch off ALT, thus killing the cancer cells. Australia has already featured prominently in this area of research: Australian-born Dr Elizabeth Blackburn won a Nobel Prize this year for her earlier ground-breaking work on telomeres. More information |