Cancer is a disease commonly found in human. It is characterized by rapidly dividing cells. It is an uncontrolled division of cells. Now a day, cancer is a very common disease due to unhygienic conditions and improper nutrition. Nutrition plays a vital role in cell division and leads to normal growth of body, organs, tissues, and cells. Normal diet consists of a variety of nutrients and protects the body against severe diseases.
The cancer cell may be any cell in any part of the body. There are many types of cancer. In every type of cell of that organ is responsible for the disease. For example in breast cancer, cancerous cells are present in the breast area, in lung cancer, cancerous cells are present in lungs and in blood cancer, cancer cells spread throughout the body through blood circulation.
Cancer cells are abnormal rapidly dividing cells
Cancer cells divide rapidly, form tumors and can spread to other tissues. Mitosis is a normal process of cell division necessary for growth, development, and repair. Normal cells divide and form daughter cells that are identical to the parent cells. When any cell in any part or organ is lost due to any reason, then mitosis repairs the damage or lost cells. There is a control system in our genes that control cell division. When this control is lost, cells start to divide abnormally and lead to tumor formation.
How cancer cells are different from normal cells?
Normal cells are mortal and die due to apoptosis or necrosis. Abnormal cells are immortal and do not die. The immune system recognizes cancerous cells through a type of cells known as natural killers. They recognize these cells as abnormal and remove from the body through T lymphocytes.
Cause of cancer
Mutations are the major causes of cancer. Mutations can occur due to changes in genes. Mutations occur due to carcinogens (cancer-causing chemicals). Carcinogens are abundantly present in our environment. Cigarette smoke contains 4000 chemicals and 36 are carcinogens. It can cause cancer in smokers as well as in passive smokers.
Cancer cells are classified according to their origin.
Carcinoma: It originates in the epithelial cells. Epithelial cells are the cells present in the membrane lining the body surfaces. These cells originate in tissues close to these surfaces. It is the major type of cancer cells in the body.
Leukemia: it can originate in cells that produce blood cells like bone marrow.
Lymphoma: also known as the myeloma. Lymph is a liquid in lymphatic vessels that pass through lymphatic organs. Lymphatic organs are thymus, spleen, lymph nodes and lymph vessels. The lymphatic system is the backbone of the immune system. It is a common type of cancer cells in immune-deficient individuals.
Sarcoma: Sarcolemma is a membrane that separates connective tissue of muscle from surrounding cells. Sarcoma cells originate in connective tissues and can affect the muscles activity.
Central Nervous System
It includes the brain and spinal cord. Nervous system plays a central role in the connectivity. These cells originate in the central nervous system.
Mesothelioma: Body layer is the first line of protection against any foreign body. It consists of three layers named as epithelium, mesothelium, and endothelium. The epithelium is the outer most layer and contains sebaceous glands and sweat glands. Mesothelium is the intermediate layer and contains connective tissues. Mesothelioma originates on mesothelium.