How does stress affect cancer?

28 Sep 2020

Stress is a constant part of everyday life, but researchers and doctors are only just starting to understand the far-reaching effects of it on our bodies and on our minds. Now, a new study led by Monash University is looking at how stress actually affects cancer cells.

That’s a topic that Associate Professor Erica Sloan, Faculty of Pharmacy and Pharmaceutical Science at Monash University has been exploring for several years now.

“What my research is showing is how stress affects both cancer cells and also the rest of the tumor that surrounds the cancer cells,” she explains. “The main thing that seems to happen when cancer cells are exposed to adrenaline, the stress neurotransmitter, is they get more invasive and they're more likely to spread.”

The role of stress
However, Dr Sloan points out that adrenaline in itself isn’t the problem, it’s the amount of adrenaline that matters.

“To be able to even stand up, we need some adrenaline in our body,” she explains. “So, at low levels, adrenaline has a normal function. The problem is during the times in our lives when we have more stress, we make massive amounts of adrenaline, but we don't always shake it off at the end of the day, so our stress tends to build up and become problematic.”

And it was this build-up of stress that Dr Sloan began to study, specifically in women who had been diagnosed with breast cancer but hadn’t started treatment yet.

The two-year study looked at reducing the effect that adrenaline has on the body using beta blockers, which have been traditionally used to reduce blood pressure. The researchers asked half the newly diagnosed patients to take a beta blocker, and the other half to take a placebo from the day they were diagnosed until a couple of days after their surgery, about 10 days later.

“What we've found is the patients taking a beta blocker had indicators showing their cancer was less likely to spread and they had fewer indications that the tumor cells were invasive. It was really quite convincing,” she says.

The future of treatment
Part of the reason Dr Sloan is so excited about this research is that beta blockers have been around for about 70 years now. They are widely used and have few side effects. Meaning, Dr Sloan says, there is an opportunity to fast track them for use in cancer patients.

“We've got a number of conversations going on with doctors at the moment about what would be the next steps,” she explains. “We need to know when to best include them in the current treatment and which beta blockers to use in which concentrations. For example, how do we best combine them with chemotherapy, radiotherapy and immunotherapy? Another arm of our research also looks at how we take this knowledge that stress affects cancer and develop a drug that's targeting at the cancer.”

Helping patients
And while Dr Sloan hopes her research will work alongside current treatments soon, she is keen to point out that the goal is not to put increased responsibility on the patient.

“We don’t want to put more stress on the patient by saying ‘deal with your diagnosis, do everything the doctor tells you, and don’t get stressed! That’s unrealistic. But I guess a way to think about it is that this knowledge is just another tool in the toolbox to help manage a cancer diagnosis, one that patients potentially have some control over.”  Dr Sloan believes acknowledging that stress is not just affecting patient wellbeing, but also is potentially affecting what's going on at the level of the cancer is the first step to further developments.

“We’d like our research to help develop ways to bolster current treatments so that the treatments actually deal with stress,” she says. “Because patients have enough to deal with as it is.”