Some novel drugs being developed to stop cancer recurrence should be considered as a future treatment for breast cancer too, researchers in Britain say. Lead author Dr. Darren Tomlinson of the University of Leeds said the researchers discovered a key protein they said they believe helps breast cancer become resistant to hormone treatments such as tamoxifen. Laboratory studies on breast cancer tissue showed resistant tumors contained excessive levels of a protein known as FGFR3. Levels of this protein were much lower in tumors that had responded to hormone treatment, suggesting an important link between FGFR3 and resistance to hormone treatment, Tomlinson said. \"The options available for treating breast cancers that return are relatively limited at the moment. It is therefore of utmost importance to identify the factors that cause this resistance to help promote the development of novel drugs that can be used to target recurrent breast cancers,\" Tomlinson said in a statement. \"Drugs are currently being made to target this protein -- FGFR3 -- in other types of cancers. Our work suggests that these drugs could potentially be made available to treat some breast cancers too and help tackle this problem of resistance.\" Breast cancer is complex, so identifying the proteins involved brings us closer to understanding how to prevent breast cancer from coming back, Dr. Valerie Speirs, the study\'s principal investigator, said. The findings were published in the International Journal of Cancer.