How does radiation cause carcinogenesis?
The mechanisms by which radiation may produce carcinogenic changes are postulated to include the induction of: (1) mutations, including alterations in the structure of single genes or chromosomes; (2) changes in gene expression, without mutations; and (3) oncogenic viruses, which, in turn, may cause neoplasia.
Is radiation a carcinogenic agent?
These studies have shown radiation to be a `universal carcinogen’, in that it will induce cancer in most tissues of most species at all ages including the fetus. The cancers induced by radiation are of the same histological types as occur spontaneously, but the distribution of types may differ.
What is radiation induced cancer?
Radiation-induced malignancies are late complications arising after radiotherapy, increasing in frequency among survivors of both pediatric and adult cancers. Genetic backgrounds harboring germline mutations in tumor suppressor genes are recognized risk factors.
What is the mechanism of radiation?
Mechanism of action. Radiation therapy works by damaging the DNA of cancerous cells. This DNA damage is caused by one of two types of energy, photon or charged particle. This damage is either direct or indirect ionization of the atoms which make up the DNA chain.
What type of carcinogen is radiation?
Several radioactive substances are considered carcinogens, but their carcinogenic activity is attributed to the radiation, for example gamma rays and alpha particles, which they emit. Common examples of non-radioactive carcinogens are inhaled asbestos, certain dioxins, and tobacco smoke.
What are the principles of carcinogenesis?
Two-Step Process of Carcinogenesis Carcinogenesis is the uncontrolled replication of tissue cells with a monoclonal character, implying origin from a single cell mutation. Chemicals that cause cancer do so either by (1) initiating a mutation or by (2) promoting replication of a mutant. Both steps are required.
Why is radiation used for cancer?
Radiation therapy kills cancer cells or slows their growth by damaging their DNA. Radiation therapy (also called radiotherapy) is a cancer treatment that uses high doses of radiation to kill cancer cells and shrink tumors.
What radiation means?
Radiation is energy that comes from a source and travels through space at the speed of light. This energy has an electric field and a magnetic field associated with it, and has wave-like properties. You could also call radiation “electromagnetic waves”.
