Mr. Qiu, who had just finished his 70th birthday, was diagnosed with lung cancer during his physical examination. Originally cheerful, he became unhappy: my body has always been very good, how old is old and cancer.
The latest statistics show that more than 8 million people worldwide die from cancer every year. For most cancers, the traditional view is that with age, the incidence of cancer increases dramatically because of the accumulation of genetic mutations in cells. Moreover, the incidence of cancer in men is much higher than in women.
Recently, Professor Thea Newman from the University of Dundee and scientists at Heriot-Watt University, Edinburgh University, and Curie College in France found that the bigger cause behind the high risk of cancer is not genetic mutation, but actually because of immunity. Caused by system recession!
Internal and external common factors lead to cancer
Although the current level of cancer treatment is steadily increasing, there are still many basic questions that remain unanswered. For example, why is the older the age, the higher the overall incidence of cancer? Of course, there are exceptions, such as breast cancer, cervical cancer, uterine cancer, ovarian cancer, thyroid cancer, etc. The incidence of these cancers will increase first and then gradually decrease with age.
Huang Yubei, an assistant researcher at the Cancer Hospital of Tianjin Medical University, believes that cancer is essentially a chronic disease caused by a series of genetic mutations accumulated over time. “And some risk factors, such as smoking, drinking, obesity, etc., increase the probability of mutations in these genes, which increases the risk of cancer.â€
Professor Wang Yuedan, deputy director of the Department of Immunology, School of Medicine, Peking University School of Medicine, also stressed that the main causes of cancer risk factors in China are external factors (such as environmental pollution, radiation, pathogen infection, etc.) and human factors (such as genetic, immune and endocrine disorders). The result of a joint action has led to the onset of cancer.
Although we are “strictly†following the advice of nutritionists and public health experts, and strive to achieve “reasonable diet, moderate exercise, smoking cessation and alcohol restriction, psychological balanceâ€, we still find that the overall incidence of cancer still increases with age. It is on a rising trend. What is unstoppable is that aging is irresistible. Does this mean that people will get cancer when they are old?
The general explanation for this problem is that the older the age, the more the mutation, the greater the risk of cancer. However, the latest research published in the Proceedings of the National Academy of Sciences (PNAS) argues that it is not just because the older the gene mutations, the stronger the risk of cancer, but with age, The decline of the immune system (mainly due to the degradation of the thymus) leads to a decrease in the number of T cells, which ultimately leads to an increase in the incidence of cancer.
Huang Yubei believes that this research is not to question the accumulation of genetic mutations that lead to the nature of cancer, but to reflect on whether genetic mutations can explain the rapid increase in cancer incidence with increasing age. Remind us that in cancer research, in addition to mutations, new ideas such as ways to promote thymic function to fight cancer may be found.
"This theory also explains why the incidence of most cancers in men is higher than that in women because the rate of degeneration of women's thymus is slower than that of men." Huang Yubei said that not all cancers will increase with age. Such as breast cancer, cervical cancer, uterine body cancer, ovarian cancer, thyroid cancer. For these cancers related to the body's hormone levels, it is at least indicated that during the development of these cancers, the degradation of the thymus is not more critical than the cumulative genetic mutations in the course of these cancers.
Immune system function gradually decreases after 25 years old
Aging can cause many changes in the body, including the immune system.
"The human immune system is an important physiological system to protect against the infection of pathogens and to ensure the stability of the human body. Without the protection of the immune system, the human body will not be able to survive in nature." In Wang Yuedan's view, although the "declining immune system is the cause of cancer" This view is more important, but it is not new. Because in the "medical immunology" textbooks of mainstream medical schools in China, the immune system has three physiological functions of defense, self-stability and surveillance. Among them, immune surveillance means that the immune system has the function of recognizing and eliminating mutant cells in the body, thereby protecting the human body from tumors.
It is estimated that the human body may have thousands of cell mutations per second on average, but the body does not develop tumors for most of the time, mainly relying on the normal monitoring function of the immune system. Wang Yuedan revealed that like other systems and organs, the body's immune system and organs also have a shelf life and will age with age. After the age of 25 years, with the increase of age, the immune system function will gradually decrease. Basically, by the age of 40, the body's immunity is about 50% of that at the age of 25, at this time, the incidence of diseases such as malignant tumors will be A significant increase.
The main cause of aging in the immune system is the degradation of the thymus. Huang Yubei further explained that the deterioration of the thymus occurs with age, which is reduced by nearly half every 16 years, and the corresponding T cell yield will decrease with age. In addition, under the combined effects of various internal and external factors, cancer cells will continue to form in the body. But under normal circumstances, the immune system will destroy new tumors before they form. Once the immune system becomes weak, the probability of cancer cells surviving increases. When the probability of cancer cell survival exceeds a certain threshold, a new tumor may form. At the same time, this threshold decreases with age, thymus degeneration, and is proportional to the production of T cells. "And there is a strong correlation between the increased risk of certain cancers and the decline in the number of new T cells."
According to the "2017 China Cancer Report" released by the National Cancer Center of China, the incidence of cancer in China is 40 years old. It was lower before, and the incidence rate increased rapidly with age. It reached its peak at 80 years old and reached the expected life expectancy of 85 years in China. At the time, the incidence of cancer in the population will reach 36% (equivalent to nearly 4 out of every 10 people with cancer). "The emergence of this cancer incidence watershed is basically consistent with the time when the body's immune system function is significantly reduced." Wang Yuedan said.
Cancer is more "favorable" male
Scientific research has shown that everyone carries oncogenic genes, and in theory cancer can occur in anyone. But a long-term observation shows that men have a higher cancer rate than women, and that is true for almost all cancer types. Almost no cancer is not "favorable to men", that is, in a particular type of cancer, such as colon cancer, the annual male incidence rate is higher than the female incidence rate.
According to the statistics of the 2017 China Cancer Report, it seems to confirm this statement. The incidence of male cancer in China is only slightly higher than that of females, mainly due to the high incidence of male digestive cancer, which may be related to male eating habits. Relatively poor.
However, the report also pointed out that the incidence of cancer among adult women between 20-50 years old in our country is higher than that of men, especially endocrine-related cancers such as breast cancer and thyroid cancer, and the incidence rate of women is much higher than that of men.
Wang Yuedan reminded that it is worth noting that after 50 years of age, the incidence of male cancer does increase faster with age, which may be related to the weak function of the male immune system, but further research evidence is needed.
In essence, aging is irresistible. Wang Yuedan said that after the human immune system is fully mature, its function declines with the increase of age. It is a natural law. At present, no appropriate measures have been found to prevent or reverse the decline of immune system function. Although thymus transplantation has certain in animal experiments. The temporary effect, but the human transplanted thymus is currently unable to truly restore the immune system to its state of youth. "So, we should face the problem of aging of the immune system objectively and accept it optimistically." (Technology Daily)
Dried Garlic Flakes,Fried Garlic Flakes,Slice Of Garlic,Roasted Garlic Slices
shandong changrong international trade co.,ltd. , https://www.changronggarliccn.com