Published on
Updated
Reading 3 min.
in collaboration with
Ivan Pourmir (medical oncologist)
The link between stress, immunity and cancer is a source of much speculation. But in a new study, researchers have established a concrete link between this famous stress and the spread of metastases. The opinion of Dr Ivan Pourmir, oncology researcher.
Regularly studied, the link that exists between the brain, our emotions and our body is not always understood. The impact of stress on cancer in particular, which we recently mentioned, is frequently induced, but difficult to prove. Today, a new study could well advance our understanding of cancer: according to research carried out on mice, chronic stress promotes not the occurrence of cancer but the spread of metastases.
The researchers imitated chronic stress in mice suffering from breast cancer (in particular by isolating them). A situation which would have accelerated their degradation since the researchers were able to observe a “frightening increase in metastatic lesions in these animals”. Metastases were up to four times more numerous in the lungs of the animals. A phenomenon that they explain by the action of the stress hormone.
Thus, glucocorticoids, the equivalent of cortisol in humans, act on a type of white blood cell involved in the body’s defense, called neutrophils. Under the effect of the hormone, these neutrophils would form structures “resembling cobwebs” called NET, specifies the press release. Structures which would unfortunately have the characteristic of creating “an environment favorable to metastases” write the researchers.
To confirm this link, the researchers also observed the development of metastases in mice after eliminating neutrophils, then destroying these NETs, but also in mice in which the stress hormone had no impact on neutrophils. . With the same result each time: the stressed mice no longer developed metastases.
The role of stress, information that could change the therapeutic approach?
Far from targeting and stigmatizing the stress felt by people with cancer, this new animal evidence could lead to positive changes in treatments. “Stress is something we can’t really avoid in cancer patients. You can imagine that if you receive a diagnosis, you can’t stop thinking about illness, insurance, or family. It is therefore very important to understand how stress affects us”, recalls Xue-Yan He, author of the study, in a press release from the Cold Spring Harbor Laboratory.
Information that also comes to the mind of Dr. Ivan Pourmir, oncology researcher and member of our committee of experts to whom we submitted this study.
“There is a world of difference between a study currently carried out on mice which follows a protocol, and the same understanding in humans, nevertheless it gives interesting leads. It remains well known that cortisol, the stress hormone that circulates in humans, interacts with immune cells. The fact that the stress hormone affects white blood cells, these neutrophils, was therefore a plausible avenue.
But above all, our expert sees in this new information a hope for a more suitable treatment. He makes two hypotheses: “First, as the researchers address, this may further pave the way for interesting non-drug interventions with the aim of reducing stress in those affected.”
But it also evokes a concrete application. “What would also be interesting to explore in more detail is the role of cortisol, which can be given synthetically (corticosteroids) as an anti-inflammatory to patients with cancer. We have already observed an association between the use of these anti-inflammatories and a poor outcome of theimmunotherapy. This could perhaps explain this link and reinforce the idea that one must be careful in the use of these corticosteroids, if it is clearly demonstrated in humans that it is through this means that the action is achieved. deleterious on the lymphocytes“.