Canadian team identifies possible new drug target for breast cancer

In collaboration with the Press Association

Scientists have found that blocking the action of a particular protein in mice predisposed to breast cancer can slow down development of the disease.

The discovery could lead to new 'targeted' drugs for the disease, or boost the effectiveness of current targeted drugs like Herceptin.

The researchers already knew that the protein, which is called PTP1B, is switched on by another protein known as ErbB2. ErbB2 is overactive in about a third of human breast cancers.

The team used a strain of mice with a 'hyperactive' copy of the ErbB2 gene - making them prone to developing breast cancer. They found that deleting the PTP1B gene slowed down cancer development and stopped the disease from spreading.

They also found that a simple pill containing a chemical known to block PTP1B's action had a similar effect.

"Cancer Research UK welcomes all new research that could eventually benefit women with breast cancer," said Ed Yong, senior cancer information officer at the charity.

"Drugs that block PTP1B may prove useful in treating the disease, but they will first need to be carefully tested in human clinical trials. "Blocking PTP1B could boost the effects of existing drugs that work like Herceptin. But not all women with breast cancer can be treated with Herceptin, so this method would only be useful in about a quarter of cases."

The study is published in the journal Nature Genetics.