How Cancer Starts
Cancer is a group of diseases that develop when the normal process of cell growth and division is disrupted. This happens when changes or mutations in cells’ DNA cause the cells to grow uncontrollably and form a mass of tissue called a tumor.
Everyone has a certain risk of developing cancer. This risk is determined by a combination of genes, lifestyle and environment. It is difficult to reduce the risk of cancer completely, but you can take steps to lower your chances.
Molecular studies of the biology of cancer led to a new understanding about how cancer begins and develops. This understanding is based on the fact that cancer develops over a long period of time as a series of genetic changes occur in precancerous cells. Each of these changes gives the precancerous cells a certain trait that together make cancer more likely to develop.
The most important change that leads to cancer is a mutation in one of the genes that control how a cell grows and divides. These changes cause cells to grow abnormally and create tumors that may spread (metastasize) to other parts of the body.
Another type of change that leads to cancer is a mutation that changes a gene that controls how a cell repairs mistakes in its DNA. This can be especially bad because DNA repair systems normally are very good at repairing errors. But if the mutation causes a cell to not repair its DNA, it will continue to multiply and become more cancerous.
These changes can happen anywhere in the body, but they are most common in cancers that affect the bone marrow and digestive tract. They can also occur in the skin or lungs.
In all of these places, cancer often starts in the blood cells. These blood cells are the cells that carry oxygen and other nutrients throughout the body.
They can also help the immune system fight off germs and other viruses that can cause infections. They can also release proteins that kill cancerous cells.
Because they rely on different kinds of nutrients than other cells, cancer cells often need more energy than other cells to survive. They may use a different way to turn these nutrients into energy, and they can produce extra waste products that build up in the body. This excess waste can harm the body and lead to other health problems.
Cancer is a group of diseases that develop when the normal process of cell growth and division is disrupted. This happens when changes or mutations in cells’ DNA cause the cells to grow uncontrollably and form a mass of tissue called a tumor. Everyone has a certain risk of developing cancer. This risk is determined by a combination of genes, lifestyle and environment. It is difficult to reduce the risk of cancer completely, but you can take steps to lower your chances. Molecular studies of the biology of cancer led to a new understanding about how cancer begins and develops. This understanding is based on the fact that cancer develops over a long period of time as a series of genetic changes occur in precancerous cells. Each of these changes gives the precancerous cells a certain trait that together make cancer more likely to develop. The most important change that leads to cancer is a mutation in one of the genes that control how a cell grows and divides. These changes cause cells to grow abnormally and create tumors that may spread (metastasize) to other parts of the body. Another type of change that leads to cancer is a mutation that changes a gene that controls how a cell repairs mistakes in its DNA. This can be especially bad because DNA repair systems normally are very good at repairing errors. But if the mutation causes a cell to not repair its DNA, it will continue to multiply and become more cancerous. These changes can happen anywhere in the body, but they are most common in cancers that affect the bone marrow and digestive tract. They can also occur in the skin or lungs. In all of these places, cancer often starts in the blood cells. These blood cells are the cells that carry oxygen and other nutrients throughout the body. They can also help the immune system fight off germs and other viruses that can cause infections. They can also release proteins that kill cancerous cells. Because they rely on different kinds of nutrients than other cells, cancer cells often need more energy than other cells to survive. They may use a different way to turn these nutrients into energy, and they can produce extra waste products that build up in the body. This excess waste can harm the body and lead to other health problems.