Dr. Tsubokura's Radiation Lecture Vol.100
Author: Masaharu Tsubokura
Editors: Akihiko Ozaki M.D., Yuki Senoo
199. Cancer risk can be inherited.
According to recent statistics , around one in every two people in Japan will develop cancer in their life. Thus, cancer has become a common disease that anyone can develop.
Various causes of cancer exist, including eating habits, heavy drinking, smoking, infectious diseases, and radiation exposure. In addition to these causative lifestyle and environmental factors, cancer can also be inherited. Obviously, hereditary cancer does not mean that cancer cells are inherited, it means that children inherent an increased cancer risk from their parents. Thus, cancer risks differ among individuals.
For example, some people black out after drinking a pint of beer, but some people can consume several cups of sake. This occurs because the levels of alcohol-metabolizing enzymes in the liver differ from person to person.
The same goes for smoking cigarettes. Smoking can certainly cause lung cancer, but the ability to detoxify the carcinogens from smoking differs among individuals. This ability to detoxify carcinogens is inherited from parents, so the risk of developing lung cancer from smoking differs in several ways from person to person.
To prevent cancer, causative agents are important, but so is the cancer history of close relatives.
200. Cancer cells change their appearance to escape recognition by the immune system.
According to recent statistics, around one in every two people in Japan will develop cancer in their life. Thus, cancer has become a common disease that anyone can develop.
Various causes of cancer exist, including eating habits, heavy drinking, smoking, infectious diseases, and radiation exposure. Besides those carcinogens, you may know that declined immune function is also associated with cancer development.
Our body’s immune system has several protective functions, including monitoring cells’ health, distinguishing our own cells (self) from the cells of foreign bodies (such as viruses and bacteria; non-self), and eliminating non-self cells.
Principally, the immune system should recognize cancer cells as a foreign body. When cancer cells grow to a certain extent, the immune system can detect and eliminate them.
However, cancer cells can change their appearance little by little to escape immune recognition. Eventually, the cancer cells will help suppress the immune system and increase its mass.
Although many underlying causes and mechanism of cancer development remain unknown, current research findings indicate that a decline in the immune system caused by stress is associated with cancer’s progression.
At last, this series has reached its two-hundredth entry! I would like to express my gratitude to the many people who support me.
The Japanese version of the manuscript was originally published in Fukushima Minyu, a local newspaper in Fukushima prefecture, Japan, 4th and 11th November 2018 was reproduced for MRIC Global under the author's permission.