The reason why some women suffering from breast cancer do not respond to treatment by the drug Tamoxifen has been revealed by British scientists.

The drug is given to most women diagnosed with breast cancer to prevent the cancer returning, but not all of them respond to the drug, and experts estimate a third get no benefit, they said.

The reason the drug does not work is because there is too much of a gene called FGFR1, said the team of scientists in the Breakthrough Breast Cancer Research Centre at The Institute of Cancer Research.

As scientists will be able to "switch off" the action of FGFR1, this discovery could lead to new treatments for these women.

They have already shown this is possible in the lab, after they introduced a drug, which "switched off" the action of FGFR1 enabling drugs like Tamoxifen to destroy cancer cells.

The BBC quoted Dr Nick Turner, who led the research, as saying," Understanding how this gene can cause Tamoxifen resistance reveals a new drug target for treating breast cancers in patients who would otherwise have a poor outcome."

He further stated," There are a number of drugs in development that stop FGFR1 working, and clinical studies are investigating whether these drugs work against cancers with too many copies of this gene. The next step is to set up a clinical trial to see whether a drug that blocks the action of this gene can counteract hormone therapy resistance in breast cancer patients. If these trials confirm our lab work we could be on the verge of a potentially exciting new treatment for breast cancer,".

Dr Lesley Walker of Cancer Research UK, the charity which helped fund the work, said," Cracking the problem of resistance to treatments such as Tamoxifen would be a major advance in treating breast cancer." (With Input from Agencies)