Popular science – what is cancer?
1. How do cancer cells come from?
Cancer cells themselves are not invading foreign races, but original cells in the human body. The DNA of normal cells mutates into cancer cells due to various complex factors during replication and division, including genes, DNA, chromosomes, etc.
On average, 1 in 10 billion normal cells may mutate into cancer cells. The human body has about 40 trillion to 60 trillion cells, so it may produce 5,000 to 20,000 cancer cells every day. But the immune system monitors your body 24 hours a day, precisely targeting these mutated cancer cells.
The immune system can remove cancer cells to the power of about 10 to the power of 5, and when the number of cancer cells in the body exceeds this number, the immune system will be powerless and watch the cancer cells grow. At this time, after escaping the powerful screening and hunting of the immune system, cancer cells will proliferate and divide exponentially in a division cycle of about 30 days, unlike normal cells that start the apoptosis mechanism and die after about 55 divisions. (Cancer cells are cells whose proliferation restrictions are lifted after genetic material is damaged.) ）
Cancer cells operate, grow and proliferate according to their own programs, and can divide about 130 to 150 times, and finally develop into tumor clumps with a diameter of 1 cm (about one billion cancer cells), which takes 10 to 20 years, which is the incubation period of cancer cells.
When cancer cells grow to a certain volume, cancer cells will fall off, leave the cancer tissue, and enter various tissues and organs of the body along with blood vessels or lymphatic vessels, which is the period of large-scale spread throughout the body.
After cancer cells spread and metastasize throughout the body, all organs and nerve tissue of the human body are in collapse and failure, but the immune system is completely powerless. There are cancer cells with “good citizen certificates” everywhere, and the immune system has completely become a headless fly, not knowing who to eliminate, and completely helpless.
2. Why does cancer hurt so much?
It is mainly caused by the invasive growth of cancer cells to the periphery invading the nerve tissue, as well as the spread of cancer cells to the nerve trunk, nerve roots, nerve endings or invasion of tissues such as the periosteum that is very rich in nerve endings. Cancer cells cause increased tension due to obstruction of cavity organs such as the intestine and stomach, or the capsule on the surface of the organ is pulled and stimulated to the pain nerve endings in the capsule, or cancer cells are infected, ulcers, and necrosis release pain factors, or compress and pull muscles, tendons and other tissues will cause pain.
3. Why does cancer kill people?
Cancer cells proliferate infinitely and take away the nutrients of normal cells in the body, and normal cells of the body will slowly die if they do not receive sufficient nutrition.
Cancer cells will fall off at a certain stage, causing heavy bleeding and life-threatening;
Cancer cell metastasis and invasion affect vital organs, resulting in loss of function;
Cancer cells can secrete a series of harmful substances during the growth process in the body. These substances enter the blood circulation and spread throughout the body, causing metabolic disorders in the human body.
