How Cancer Starts In The Human Body

Cells are the basic units that make up the human body. These cells grow and divide to form new cells as needed by the body. Cells usually die when they become old or damaged to replace new cells that take their place. When cells divide and grow, cancer occurs. Cancer has more than 100 different diseases, and can begin anywhere in the body.

Cancer is defined by the area in which it starts, and the type of cell from which it occurs. For example, cancer that starts in the lungs and spreads to the liver is known to be lung cancer, although it spreads to the liver.
Cancer is divided into different types including:
Sarcoma a connective tissue cancer such as: bone, muscle, cartilage, blood vessels, and leukemia that arises from the bone marrow, lymphoma and spinal cord that affects the immune system.

How to start cancer :

The process of cell division in the body is regulated by the production of signals to control the amount and frequency of cell division, and cancer occurs as a result of changes in genes that control the way the cells work, especially the way of growth and division, so cancer can be considered a genetic disease or In some cases, the genetic changes that cause cancer may be inherited from one or both parents and may arise during a person's life as a result of errors that occur during cell division or as a result of DNA damage caused by exposure to certain environmental stimuli. For example:
 Chemicals in tobacco smoke, and exposure to radiation, such as UV rays from the sun. Cancer can be said to be caused by many genetic changes known as mutations, which mean that the gene has been damaged, lost or copied twice. Mutations in certain genes may mean that the cell will begin to produce many proteins that stimulate cell division, The mutation causes the cell to stop producing proteins that stimulate cell division, or abnormal proteins may be produced that work abnormally. Cancer is caused by the effect of three major types of genes, known as cancer stimuli, as follows:

• Proto-oncogenes: These genes are involved in regulating the growth and division of normal cells. Genetic changes increase the activity of these genes, allowing cells to grow and survive, even though their life span is over.

• DNA repair genes. These genes are involved in the repair of damaged DNA, help identify errors that occur when copying DNA to form a new cell, and if new DNA does not fully match the old DNA , These genes repair mismatches and error correction. Genetic changes and mutations in these genes lead to the development of additional mutations in other genes. These mutations can cause normal cells to become cancerous. Risk factors for cancer As mentioned above, cancer occurs due to a defect in the genes, and some factors may increase the risk of cancer, among which are the following:

• Cancer can take decades to happen, so most people aged 65 or over. Cancer can affect all age groups, but it is more common in older people. Lifestyle: Some lifestyle options may increase the chance of cancer. Examples of these options include:

1. Smoking, drinking alcohol, excessive exposure to the sun, obesity, and the practice of unsafe sex.
2. Family history: Some types of cancer may increase the risk of cancer if a family member has this type of cancer.

 Environmental factors Environmental factors that can increase the risk of cancer include:

•  Tobacco smoke Tobacco smoke contains carcinogens that significantly increase the risk of lung, mouth, throat, esophagus, kidney, and bladder cancers.

•  Contaminants in the air or water, such as: Asbestos which increases the chance of lung cancer or industrial waste. Insecticides are associated with an increased risk of certain cancers, such as leukemia and non-Hodgkin lymphoma.

• Exposure to radiation, as is the case with prolonged exposure to ultraviolet radiation from the sun, increasing the chance of skin cancer.

•  Ionizing radiation such as x-ray, tomography, uranium radiation, and radiation from alpha, beta and gamma sources. Other carcinogens include benzene, nickel, cadmium, vinyl chloride, benzidine, nitrozamine and aflatoxin. Exposure to radon, one of the types of radioactive gases released from the soil, increases the risk of lung cancer.

•  Geographic area: The risk of cancer varies according to where a person lives. For example, the risk of colon cancer and breast cancer is low in Japan, but the risk is increasing among Japanese emigrating to the United States. In contrast, the incidence of stomach cancer is high among the Japanese .