A new DNA 'chip' could pave the way for breast cancer treatments tailored to individual patients, according to French biotechnology company Ipsogen. Alane Koki, the firm's scientific director, told delegates attending the fourth European Breast Cancer Conference in Hamburg that the breast cancer profile chip (BCPC) could be available this summer. The chip, which reveals the genetic profile of a particular tumour, could increase survival rates and stop patients undergoing needless chemotherapy. Another recent study shows that genetic profiling can help pinpoint adults with a type of leukaemia who are most likely to respond to chemotherapy.
DNA chips, or microarrays, are being increasingly used in research to look at many different genes or pieces of DNA at once. The BCPC is an example of a microarray designed to look at gene expression - which genes are switched on or off in a particular tissue sample. Cancer is the result of genetic changes that lead to unregulated cell growth, but the genes involved vary, even between tumours that affect the same body tissue. By examining the genes switched on in a particular tumour, scientists can work out which drugs will be most effective against the cancer cells. The BCPC looks at the activity of 900 key genes known to play a role in breast cancer, some of which affect the likelihood of a cancer spreading, while others determine how it will respond to different treatments.
'To our knowledge the BCPC will be the first microarray diagnostic tool available to local pathology laboratories', said Koki. She added that it will provide 'useful information to deliver a more personalised approach to patient care'. Breast cancer accounts for around a quarter of all cancers in European women: over 40,000 UK women were diagnosed with the disease in the year 2000, the latest year for which figures are available. Ipsogen is now planning clinical trials of its BCPC test, after which it will seek approval to market the new diagnostic tool.
Microarray technology could also help in the treatment of patients with adult T-cell acute lymphocytic leukaemia (T-ALL), Italian researchers report. Scientists at the University 'La Sapienza', Rome, studied 33 people with T-ALL, and compared the genetic profiles of the blood cancer cells of patients that did respond to chemotherapy with those that did not. They found that leukaemia cells that expressed (switched on) a gene called IL-8 at high levels were resistant to treatment. The study is published in the journal Blood.