Beta Blockers Could Reduce Breast Cancer Spread and Prolong Lives
New findings show that beta-blockers – a class of medications taken to treat high blood pressure– could reduce the chances that breast cancer tumors will spread, and prolong life. Researchers from Queen's Medical Centre, Nottingham University Hospital NHS Trust, Nottingham, UK studied a group of women with breast cancer, finding that beta-blockers significantly reduced the chances of breast cancer metastasis, improving survival rates.
The study is believed to be the first to examine the effect of beta blockers for improving outcomes in women diagnosed with breast cancer. Previous studies have shown that beta blockers can also slow melanoma tumor growth.
Scientists looked at three groups of women – two groups of women undergoing breast cancer treatment and being treated for hypertension, and one group of women without high blood pressure undergoing breast cancer treatment. The group of women who were receiving beta blockers as opposed to other drugs for treating high blood pressure had a 71 percent lower chance of dying from breast cancer compared to the other groups.
Dr. Des Powe, a senior healthcare research scientist at Queen's Medical Centre says, “We were also able to study the presence of one receptor for beta-blockers, β2AR, as a potential biomarker for predicting clinical response to beta-blocker treatment, but we did not find that this correlated directly to the outcome of treatment. We are currently looking at other target receptors as predictors of clinical outcome.”
In the study of 466 patients, 43 were already taking beta blockers. Women already taking the medications had a lower incidence of breast cancer metastasis locally and to other organs.
Beta blockers act on stress hormones. The beta blocker Inderal has been used to alleviate “stage fright” and reduce anxiety by blocking the release of adrenalin and other substances released by the sympathetic nervous system. Beta blockers block tumor promoting hormones that activate cancer cells and cause them to spread. Studies have also linked stress to spread of ovarian cancer, generating interest in targeting hormones in the body that fuel cancer and shorten lifespan.
The researchers aren’t sure if the drugs reduced the chances of cancer spread because they treat high blood pressure or from the direct effect of blocking beta receptors – molecules that stimulate the nervous system. Beta blockers specifically seem to have benefits for breast cancer compared to other high blood pressure drugs because women in the study receiving other antihypertensives did not experience a reduction in tumor growth compared to the beta blocker group.
"Our first study is relatively small, and we now intend to validate it in a larger group," says Dr. Powe. "We will be looking for funding and collaborators to test the effectiveness of beta-blocker treatment on patients diagnosed with breast cancer. We are very encouraged by these first results which have already shown that by using a well-established, safe, and cost-effective drug, we can take another step on the road to targeted therapy in breast cancer."
Beta blockers could be used to slow breast cancer tumors, and might be useful as a supplement to breast cancer treatment. From the study findings, beta blockers might also halt the spread of breast cancer to other organs, but require validation in larger studies.