Regular exercise reverses a genetic predisposition to cancer

In patients with Lynch syndrome, who are genetically predisposed to develop colon cancer at a young age, vigorous exercise may reduce the risk of cancer.

Our life is the result of the interaction between the genes inherited from our parents (genetics) and all the modifications that our lifestyle causes these genes to undergo (epigenetics).

Therefore, not everything is decided at birth: for example, you can be born with a gene that predisposes you to obesity or even cancer, but with rare exceptions (pediatric cancers or certain serious genetic diseases), these genes they are just one of the aspects involved in the development of these diseases, a very real genetic predisposition, but which, however, continues to be strongly influenced by a series of external factors, in particular by our lifestyles.

We are what we make of our genes, by our way of life.

Lynch syndrome

Lynch syndrome (hereditary non-polyposis colorectal cancer (HNPCC)) is a good example of a genetic predisposition that increases the risk of cancer. This syndrome dramatically increases the risk of colorectal cancer (60% lifetime risk of developing the disease) due to mutations that interfere with DNA repair and thus promote the appearance of abnormal cells that can become cancerous. .

Lynch syndrome is among the most common inherited cancer syndromes, affecting approximately one in 300 people, and is also associated with an increased risk of tumors of the endometrium, stomach, urinary tract, pancreas, gallbladder, and brain .

Mitigate risk

Exercise represents a very interesting approach to mitigating the risk of cancer that threatens people with Lynch syndrome.

On the one hand, several studies have shown that regular physical activity is associated with a significant reduction (20%) of several types of cancer, including colorectal cancer.1.

On the other hand, a retrospective analysis of patients with Lynch syndrome revealed that those who were more active (about an hour of walking a day) had about a 30% reduced risk of colorectal cancer compared to those who were sedentary.2.

A recent study suggests that this protective effect may be related to the anti-inflammatory action and improvement of the immune response of exercise.3.

In this study, researchers recruited volunteers diagnosed with Lynch syndrome, but who had not been diagnosed with colorectal cancer. They separated them into two groups, a control group with no physical activity and an intervention group, where the participants were subjected to regular stationary bike training for a year.

Biochemical analysis of blood samples taken during the procedure indicates that exercise causes a significant decrease in the levels of prostaglandin E2, an inflammatory molecule that plays a very important role in the development of colorectal cancer.

They also noted that patients who underwent the exercise program had higher numbers of CD8+ T lymphocytes and natural killer (NK) cells in their blood, two types of immune cells involved in recognizing and eliminating cancer cells.

Therefore, these results suggest that exercise positively influences the innate and adaptive immune system and that this modulation of immunity plays a key role in its anticancer effects.

This mechanism is conserved in individuals genetically predisposed to colorectal cancer, providing these individuals with the opportunity to adopt an active lifestyle to overcome the bad genes.

One more proof that our lifestyle is really decisive for our health and that the daily choices we make (diet, exercise, sleep, regulation of our body weight) play a determining role in our health, even with the worst predispositions. as serious as cancer.

We are not the helpless victim of the action of our genes, as many like to think.

♦ 1. McTiernan A et al. Physical activity in cancer prevention and survival: a systematic review. Med. science Sports exercise 2019; 51:1252-1261.

♦ 2. Dashti SG et al. Physical activity and risk of colorectal cancer in Lynch syndrome. International J. Cancer 2018; 143:2250-2260.

♦ 3. Deng N et al. Exercise training reduces the inflammatory response and promotes intestinal mucosa-associated immunity in Lynch syndrome. Clin. Cancer Res.published on September 19, 2023.