Cancer etiology is the study of the origins of cancer, and can also refer to the specific cause of a certain type of cancer. Work in cancer etiology has made it possible to have a basic idea of how cancer forms. This is potentially important in preventing and curing cancer. The study of the origins of cancer has identified, for instance, the basic cause of cancer as well as environmental hazards that contribute to developing cancer.
Most cancer is caused by mutations in genes in the cells of the body. Specifically, errors can be incorporated in the deoxyribonucleic acid (DNA) of a cell which is passed on to surviving daughter cells. If the genes which are responsible for regulating cell division are damaged, cells can multiply too quickly which can eventually lead to cancer. Damage to genes responsible for DNA repair or those that regulate a cell's lifespan can also lead to cell division that is too rapid. The occurrence of some mutations is likely to be inevitable, but radiation, certain chemicals, and viruses raise the likelihood of DNA damage.
A better understanding of cancer etiology has led to research efforts along the lines described above. For instance, programmed cell death is called apoptosis, and mutations in genes that control this can cause cancer cells to outlive what would otherwise be their normal lifespans. Research into some new cancer drugs hopes to find ways to cause cancer cells to undergo apoptosis by means of signaling chemicals. Another possible drug treatment could include ways to fix damaged genes that are supposed to suppress cancerous mutations.
Some people have a higher likelihood of developing certain cancers due to the genes they inherited from their ancestors. Identifying these genes could increase the understanding of cancer etiology. Identifying specific mutations may also make it possible to develop more sophisticated ways to fight cancer.
The study of cancer etiology has had many practical applications. For instance, asbestos, a mineral formerly used in flame retardant materials, was either banned or phased out in many countries after it was found to cause a specific type of lung cancer associated only with asbestos exposure. The association established between tobacco and cancer has led to an ongoing decline in smoking rates. Overexposure to sunlight, found to be associated with skin cancer, has made it possible to take precaution by wearing more clothing or sunscreen. The finding that some viruses can cause cancer makes it possible to prevent certain cancers by vaccination.