Research ArticleCancer

The brain microenvironment mediates resistance in luminal breast cancer to PI3K inhibition through HER3 activation

See allHide authors and affiliations

Science Translational Medicine  24 May 2017:
Vol. 9, Issue 391, eaal4682
DOI: 10.1126/scitranslmed.aal4682

You are currently viewing the editor's summary.

View Full Text

Log in to view the full text

Log in through your institution

Log in through your institution

No safe haven for metastases

Although targeted therapies for cancer offer great promise, they are often much less effective against brain metastases than against peripheral tumors. This is generally attributed to the drugs’ difficulty in penetrating the blood-brain barrier, but Kodack et al. now demonstrate that this is not the only reason. The authors discovered that, at least in breast cancer, the brain microenvironment itself plays a role in treatment resistance in metastatic tumors. Using mouse models and human cancer samples, the researchers found increased expression of human epidermal growth factor receptor 3 (HER3) in breast cancer–associated brain lesions and showed that it facilitates the tumors’ survival in the presence of targeted treatment and that inhibiting can help overcome resistance to therapy.