How does chemo work against cancer?
Chemotherapy targets cells that are fast-growing, such as cancer cells. Chemo will work throughout your body as opposed to radiation or Surgery which target specific areas. But it may also affect other fast-growing healthy cells, such as skin, hair, intestines, and bone marrow cells. That is why Chemotherapy causes some side effects.
For the treatment of cancer, several different forms of Chemotherapy medications are used either individually or in conjunction with other medicines or treatments. These medications vary in their chemical composition, their process of formulation and administration, effectiveness in treating other forms of cancer, and side effects they may have.
Cancer Cells and Chemotherapy
Cancerous tumours are characterized by excessive cell division, which is no longer regulated. Once ‘Normal cells’ come into contact with similar cells, they stop dividing — a process known as contact inhibition. Cancerous cells lose this capacity. When they touch similar cells, cancer cells lose the ability to avoid dividing.
The cell division cycle goes from the resting phase, through active growing phases, and then to mitosis (division). Chemotherapy’s ability to destroy cancer cells relies on its ability to stop the division of cells. Cancer drugs typically operate by disrupting the RNA or DNA that tells the cell how to replicate itself. When the cancer cells cannot divide, they die.
The Chemotherapy drugs which destroy cancer cells when they are dividing are called cell-cycle specific. The Chemotherapy drugs which kill cancer cells at rest are called cell-cycle non-specific. Chemotherapy scheduling is depended on the type of cells, the rate at which they split, and time that a drug is likely to be successful. That is why Chemotherapy is typically administered in cycles.
Chemotherapy is most effective in killing rapidly-dividing cells. Chemo does not know the difference between healthy cells and cancer cells. The healthy cells will grow back, but side effects will occur in the meantime. The healthy cells most commonly affected by Chemotherapy are the blood cells, the cells in the mouth, stomach and bowel, and the hair follicles; resulting in low blood counts, mouth sores, nausea, diarrhoea, and Hair loss. Different medicines may affect different parts of the body.