Fatigue and depression may cause cancer

Prolonged stress and depression may possibly trigger cancer not only in mice, but also in humans, scientists at the Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences have found.

Cancer is thought to occur when cells with the wrong genetic information accumulate in a certain area of the body. A healthy immune system usually handles them successfully, but if a malfunction occurs, the mutated cells divide uncontrollably, forming a tumor.

Risk factors include unfavorable environment, unhealthy diet, bad habits, infectious diseases. And chronic stress, which alters metabolism, shortens telomere length (the end sections of chromosomes), increases levels of adrenaline, noradrenaline and cortisol, which affect many organs, including the immune system.

Studies have shown that stress hormones can negatively affect cyclooxygenase-2, an enzyme that forms inflammation, a precursor of some cancers. When stressed, the adrenal glands produce more norepinephrine and cortisol. Both of these hormones affect neutrophils, immune system cells that release special proteins that "wake up" tumor cells. There is evidence that men taking adrenaline receptor blockers to lower blood pressure have a 50 percent lower incidence of prostate cancer.

Of course, this does not mean that everyone who experiences difficult emotional moments will necessarily get cancer. Those who had a difficult childhood are at risk.

The Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences has been conducting research on mice for several years - studying the link between stress and the risk of developing cancer. It was found that chronic social stress impairs immunity and accelerates the metastasis of malignant neoplasms. And returning the psycho-emotional state to normal is often more effective than measures to directly activate the immune system.

Scientists have focused on the hypothalamus, a part of the brain involved in the chain of behavioral, immune and neuroendocrine processes. In animals with a predisposition to cancer, the activity of genes involved in carcinogenesis was elevated. That is, it is likely that tumor risk associated with chronic stress is laid down at the genomic level in the brain.

For now, this is purely basic science, but if the project is successful, the prospects for practical applications will open up. Scientists hope to find new target genes for pharmacological effects that slow down tumor growth.

The effect of stress hormones on the immune system has been proven, but the real biological picture is likely to be much more complex.

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