New target in breast cancer paves way for one-two punch.

The breast cancer drug Herceptin® is used to treat cancers that produce too much of a particular protein (called ErbB or Her2).  The ErbB protein sends signals that cause cells to reproduce and Herceptin® blocks those signals.  A major problem with this treatment is that many cancers become resistant to the treatment.

New research has identified another protein (P-Rex1) in the same pathway that may be a target for a second attack on the same process.  The P-Rex1 protein is found at abnormally high levels in breast cancer, making it an attractive target.