Propranolol can resensitize HER2+ cells to trastuzumab

Fallleaves

Unfortunately, resistance to trastuzumab (Herceptin) develops in many people who take it within 1 to 2 years. There are a lot of clinical trials being done right now of different combinations of trastuzumab and various new drugs to try and reverse that resistance.

This study showed that propranolol (Inderal) could extend the effectiveness of trastazumab. And it would be much cheaper than many of the experimental drugs they are trying. Propranolol is a beta-blocker used for cardiac disease and various other things like migraines and anxiety, and a month's supply costs well under $100. On the other hand, everolimus (Afinitor), which has been tested with trastuzumab to reverse resistance, costs about $11,000 for a one month supply. I mention everolimus for comparison because it blocks the same pathway as propranolol, the PI3K/Akt/mTOR pathway.

β2-AR signaling controls trastuzumab resistance-dependent pathway.

"We also demonstrate that β-blocker propranolol not only enhances the antitumor activities of trastuzumab but also re-sensitizes the resistant cells to trastuzumab.

"Our retrospective study shows that concurrent treatment of β-blocker and trastuzumab significantly improved progression-free survival and overall survival in the patients with Her2-overexpressing metastatic breast cancer, implicating the possibility for combination therapy with trastuzumab plus β-blocker in Her2-overexpressing breast cancer."

http://www.nature.com/onc/journal/v35/n1/full/onc2...