There have been studies that have suggested that prolonged stress could play a role in the establishment and progression of cancer, without fully explaining how it would happen. But there are also many that have reached opposite conclusions. So, although we cannot consider stress can cause cancer as a direct cause, it seems that it could influence its development in some way.
What studies show it?
Studies with rats to understand if stress can cause cancer
Continued stress in mice has shown it contributes to cancer because it decreases the action of tumor suppressors. In fact, if stressed mice are exposed to carcinogens, they quickly develop tumors. The reason is that in stressful conditions they produce a series of hormones (glucocorticoids) that interfere with the function of the p53 tumor suppressor. With this defense weakened, cells damaged by carcinogens become malignant easily, as squamous cell carcinoma or melanoma cases.
Adrenaline could have a similar effect, and make malignant tumors worse. Stress only creates conditions in which a cancer caused by other reasons can progress more easily. It’s similar to other factors that can help because they facilitate an environment where cancer thrives, for example, chronic inflammation.
In another study it was also seen that the number of breast cancers doubled in a group of stressed rats.
Mice transplanted with cancer cells, developed smaller tumors if they lived in better environments. Increased exercise may also have contributed to this fact.
Likewise, studies show that if B-adrenoreceptor blockers are given to mice, the formation of metastases is reduced. B-adrenoreceptor blockers are drugs that are used to treat heart problems. However, one of the side effects they have is a reduction in stress levels.
But… how does stress affect us?
Humans also make glucocorticoids and adrenaline when things go wrong. But it’s unlikely that we’d be able to generate the sustained levels seen in mice and rats. Furthermore, we’d have to simultaneously subject ourselves to significant doses of radiation so that the conditions were similar.
However, this does not mean that we should not consider the influence of stress on cancer as a disease. Let’s not forget that the mind and the body are not independent entities. But, the mind influences the way we deal with a problem. Therefore, any strategy that reinforces our state of mind, prevents us from producing certain hormones related to stress. This could protect us, hinder the progress of a cancer, and help when receiving therapy. In conclusion, stress can cause cancer by decreasing the action of tumor suppressors.
“Stressed man” photo by Andrea Piacquadio: https://www.pexels.com/photo/man-showing-distress-3777572/