Cancer cells are under the relentless drive to spread, this metastasis is responsible for a majority of cancer-related deaths.

The most ominous part of the body to which cancer can spread is the brain leading to what is called brain metastasis.

Because the brain is highly unique in its anatomy and biology, breast cancer cells circulating in the blood would need to exhibit unique features to exploit the brain’s native nutrient sources – neurochemicals.

Interestingly, adrenaline is a major neurochemical that is abundant during stress and also narrows blood vessels resulting in elevated blood pressure.

Since many people are on regular blood pressure medicine, this provides an interesting avenue for researchers.

In a study conducted at City of Hope hospital, researchers led by Michael Lew, M.D., chair and clinical professor in the department of Anesthesiology, investigated with bioinformatics whether patients on beta blockers (a specific blood pressure medicine that blocks the adrenaline receptor) had fewer metastases using a City of Hope patient database.

Results were published in Oncology Reports.

In parallel, they looked at the cancer biology of triple negative breast cancers and adrenaline in the laboratory.

“We found that at City of Hope, breast cancer patients on beta blockers at or near the time of their surgery had decreased postoperative cancer recurrence and metastases, this intriguing findings led to a collaboration with Dr. Jandial and his laboratory to investigate the underlying cancer biology” Dr Lew said.

This study was initiated by a retrospective study of the metastatic breast cancer patient population at City of Hope, comparing patients who were on beta-blockers versus patients who were not taking beta-blockers.

The clinical analysis suggested that there was decreased metastasis in patients taking beta-blockers.

Further investigations of the effects of beta-blockers in the laboratory found high receptor expression in both Triple Negative (TN) breast cancer and brain metastasis tissues but not in Her2 breast cancer and brain metastasis tissues.

Researchers applied a variety of beta-blockers used in the clinic to the breast cancer and brain metastasis cells in the laboratory in order to observe three traits of metastasis- proliferation, migration, and invasion.

It was found that brain metastases cells were more sensitive than primary breast cancer cells to select beta-blocker treatments.

There was a decrease in proliferation, migration, and invasion in brain metastasis cells when treated with beta-blockers.

Finally, addition to using the beta-blockers alone, the team added beta-blockers to cells treated with drugs that would activate the receptor.

"Because biological systems, both healthy and cancerous, strive for efficiency we wondered if breast cancer cells evolved to respond to natural brain chemicals such as epinephrine” - Rahul Jandial. M.D., Ph.D., associate professor in the department of Surgery

Although activating the receptor increased metastatic traits, beta-blockers decreased those effects.

“Both clinical and lab research showed beta-blockers may decrease metastasis, suggesting potential improvements in targeting brain metastasis from triple negative breast cancer.” – Cecilia Choy, Post-doctoral Fellow at City of Hope.

Source: Oncology Reports