A current focus of breast cancer research is to find drugs that work by targeting specific molecules involved in breast cancer development. For example, some breast cancer cells have an overactive HER2/neu gene, which causes overproduction of the HER2/neu protein and leads to more-aggressive tumors. Drugs that inactivate or otherwise target the HER2/neu protein are usually given in combination with other anticancer drugs. Some targeted therapies, including antibodies and small molecule inhibitors, are already in use.
In addition to HER2, there are other known or potential targets for drugs, some of which are available while others are in development.
Newer targeted drugs we commonly use in breast cancer include: