The Scientist - USA (2020-04)

04.2020 | THE SCIENTIST 45

injected mice that had malignant mela-

noma with either epinephrine or saline

and found that the hormone indeed

reduced the growth of tumors, but to a

lesser degree than what was observed

in the mice that had access to a wheel.

Something else had to be involved.

To find out what, our team tested the

effects of interleukin-6, which we sus-

pected was the additional exercise fac-

tor involved in tumor homing of immune

cells. When we exposed inactive mice to

both epinephrine and interleukin-6, the

rodents’ immune systems attacked the

tumors as effectively as if the animals

had been running.^8

While much remains to be learned

about how physical exercise influences

cancer, evidence shows that exercise

training is safe and feasible for patients

with the disease and contributes to their

physical and psychosocial health. (See

“Exercise and Depression” on page 44.)

Being active may even delay disease

progression and improve survival. A

growing number of patients, including

Mathilde, are undergoing exercise train-

ing to fight physical deterioration dur-

ing cancer treatment. As they do so, sci-

entists are working hard to understand

the pathways by which physical activity

results in anticancer activity. g

Bente Klarlund Pedersen is a professor

of integrative medicine at the University

of Copenhagen and a specialist in infec-

tious diseases and internal medicine at

the university’s Rigshospitalet hospital.

She directs both the Centre of Inflamma-

tion and Metabolism and the Centre for

Physical Activity Research.

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AND S TAY OUT: Exercise activates natural killer

cells (purple) and helps them home to tumors.

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