Study sheds light on Herceptin resistance in breast cancer

In collaboration with the Press Association

A new study has shed light on why some patients taking the breast cancer drug Herceptin (trastuzumab) become resistant to the treatment.

Herceptin targets the HER2 protein found on the cells of around one in four breast cancers, but nearly half of people who take the drug become resistant.

Researchers from the Netherlands Cancer Institute conducted a study to look for genes involved in Herceptin resistance and have identified biomarkers that could predict which patients are likely to develop resistance.

Publishing their findings in the journal Cancer Cell, they reveal that changes in activity of an internal signalling pathway, known as the 'PI3K pathway', could be used to predict Herceptin resistance, particularly when measured alongside the activity of a protein called PTEN, which had previously been linked to Herceptin resistance.

Lead researcher Dr Rene Bernards noted: "It is too early to use these biomarkers; further validation studies are required before they can be used in the clinic.

"Nevertheless, it is likely that these findings will lead to a better understanding of resistance mechanisms and how to circumvent them, as well as more reliable identification of the most effective treatment for individual patients."