Stress is bad, right? It hurts and it’s bad for you. The causes are different for everyone. But how exactly does stress – and nerves – relate to a chronic disease like cancer?

Monash University Associate Professor Erica Sloan, a scientist specializing in cancer biology and neuroimmunology – how nerves talk to immune cells – started digging into this question 15 years ago and is now able to say that she is very close to the answers.

These responses involve all of these things – nerves, cells, the immune system, bodily organs, as well as ancient physiological phenomena known as the “fight or flight” response, or stress response.

Humans and mammals evolved to have this response, so when we are in danger the brain decides to run or fight.

The problem is that the rapid hormonal and physiological changes that accompany the stress response (triggered by the nerves) can, over time, take its toll on the body.

And modern Western life is increasingly stressful for many. The whole mindfulness industry is fueled by this – humans are too stressed out, learn from Buddhists, be in the moment rather than the past or the future, calm down, breathe. With less stress, say the ancients, comes better health.

Effects of stress on immune cells

Associate Professor Sloan’s experience was purely in cancer research. She did her PhD at the Peter MacCallum Cancer Center until 2003, examining how cancer spreads. Then she did postdoctoral studies in the United States in neuroimmunology, examining how stress affects immune cells in lymphoid organs such as lymph nodes.

The answer to that investigation was, yes, immune cells are sensitive to signals from neurotransmitters in the brain, which affects how a virus like HIV enters these cells.

“There was also evidence at that time that HIV-positive patients who were very stressed,” she says, “had a higher viral load at the time of diagnosis and did not respond as well to viral treatments. But the mechanisms for this were not known. “

“Quantifying stress is a challenge. So we focused on how the body experiences stress – how it interprets it and what it does with it. “

With more research came stronger ties. This link between the stress response and the likes of HIV and various cancers has become much clearer.

“This type of thinking has not always been widely accepted by Western medicine,” says Associate Professor Sloan. “Oriental medicine has accepted it for a long time. Our goal was to demonstrate its molecular and cellular basis, so that we could target it with drugs. “

Now in research that Dr Norman Swan’s Checkup on Radio National called “extraordinary”, Associate Professor Sloan and a team of researchers from Monash have discovered that a heart and high blood pressure drug can reduce the spread and growth of breast cancer and reduce the risk of death in patients with breast cancer.

The drug is Carvedilol, a beta blocker. It also blocks stress.

“Beta blockers are drugs invented in the 1950s that prevent the heart and cardiovascular system from hearing a stress signal,” she says. “They ease the stress response and stabilize the heart so that it can respond in a more measured way.”

The drug class is in its third generation; Carvedilol is relatively new. It can be used for heart disease and blood pressure, but also off-label for stage fright or anxiety.

The main discovery – before this work – was that stress acts on cancer cells (as well as HIV) and makes them more able to spread throughout the body. In preclinical models, Professor Sloan’s team found that the drug prevented this from happening, which in turn showed that nerves could affect tumors.

After the preclinical studies, the team – along with collaborators in Scandinavia – looked at hospital data on women with breast cancer who took the drug and found that they did much better to stay alive and keep health. remote cancer.

They also conducted a clinical test in Melbourne two years ago with cancer patients and the similar beta-blocker drug Propranolol, which showed equally positive results.

Where to go from here?

Now what? At the moment, research is mainly limited to breast cancer, although work is underway on beta-blockers for pancreatic and blood cancers.

“From the results of my lab and others, I suspect that most cancers in the body will be sensitive to the nerves. Brain cancers are a whole different story. It’s a hot topic in cancer research right now.

Read more: What can we learn about chronic diseases from COVID-19?

A big scientific hurdle for Associate Professor Sloan, and others studying this potentially life-saving connection, is the question of how to define stress. Stress levels are different in different people. One person’s high stress situation may be “no problem” for another person.

“That’s why the field of research hasn’t taken off for so long,” she says. “Quantifying stress is a challenge. So we focused on how the body experiences stress – how it interprets it and what it does with it. Our job is to find out how cancer cells and immune cells respond to the “fight or flight” signal. “

As cancer patients know all too well, a cancer diagnosis is inherently stressful.

“How do we recognize this?” Professor Sloan asks, “and treat not only the cancer, but the well-being of the patient?”