Women with a particular pattern of genE activity are less likely to respond to the breast cancer drug docetaxel.
We now know that many different genes are involved in breast cancer. In individual cases, some of these genes may be more active than others - leADIng to the idea of analysing a tumor to discover the underlying genetic 'signature'.

Researchers at Baylor College of Medicine, Texas, US, now show that these genetic sigNatures may be linked to a woman's response to breast cancer treatments. Using biopsy samples from 24 patients, they found that certain patterns of gene activity are linked to response or non-response to the drug docetaxel, which is often used in an attempt to improve mortality after surgery. The study opens up the possibility of using the genetic signature of a woman's breast cancer to assess the likelihood that she will respond to docetaxel. Those who are unlikely to respond could then be offered an alteRNAtive treatment.

Source
The Lancet 2nd August 2003