Chip technology that exploits genetic information promises to be one of the most important instruments for the prognosis of cancer on the horizon, delegates were told today (19 October 2002) at the European Society for Medical Oncology Congress in Nice, France.
Cancer is caused by alterations - or mutations - in genes and other cell abnormalities. Information from the Human Genome Project now provides a valuable tool in understanding the genetic basis of cancer and its diagnosis. DNA microarrays, also known as 'chips', have been developed to analyse types of cancer.
Genetic material, DNA and RNA, is removed from the tumour and labelled. "This tissue sample is placed on the chip, which is a plastic device with a very small glass chamber on it, barely visible to the naked eye," Dr Martin Fey, from the Institute of Medical Oncology, Bern, Switzerland, explained. "Chip technology enables you to screen all the characteristics that will show you how the tumour might behave. Thousands of genes can be tested simultaneously."
Although scientists have a good deal of knowledge of genes, current techniques to predict the prognosis are very time consuming. Using chip technology and computer analysis, the tests can be accomplished in just a few hours. "Despite the great advantages of speed, chip technology should not replace the traditional methods of analysis," he said. More effort needs to be invested in quality control and clinical trials. Still in its development phase, and very expensive, Dr Fey anticipates that microarray analysis may be available in major research centres in a few years but is not likely to be widely used in routine clinical practice for a decade.
The chip technology, however, remains very promising because it can pick up isolated genetic traits as well as provide a complete picture.
"Predictive factors are much more important, since they may guide us in our choice of treatment, tailored to individual tumour patients. It appears that the chip technology is well suited to help us in this way," said Dr Fey.