What is radiation induced carcinogenesis?
What is radiation induced carcinogenesis?
Radiation carcinogenesis is a biological phenomenon whereby living normal cells are damaged by ionizing radiations, which starts a progressive process causing the surviving cells to change their phenotype such that normal controls of cell death and apoptosis are lost and uncontrolled cancerous growth is initiated.
What is carcinogenesis PPT?
INTRODUCTION • Carcinogenesis or oncogenesis or tumorigenesis means mechanism of induction of tumours (pathogenesis of cancer); • agents which can induce tumours are called carcinogens (etiology of cancer).
How is radiation a carcinogen?
High-energy radiation, such as x-rays, gamma rays, alpha particles, beta particles, and neutrons, can damage DNA and cause cancer. These forms of radiation can be released in accidents at nuclear power plants and when atomic weapons are made, tested, or used.
Is radiation an example of carcinogen?
Radiation is a carcinogen, interacting with DNA to produce a range of mutations. Irradiated cells also show genomic instability, as do adjacent non-irradiated cells (the bystander effect); the importance to carcinogenesis remains to be established.
Which of the following is most sensitive to radiation induced carcinogenesis?
Lymphocytes (white blood cells) and cells which produce blood are constantly regenerating, and are, therefore, the most sensitive.
What is carcinogenic effect?
… A carcinogen is a substance, organism or agent capable of causing cancer. Carcinogens may occur naturally in the environment (such as ultraviolet rays in sunlight and certain viruses) or may be generated by humans (such as automobile exhaust fumes and cigarette smoke).
What are the 3 types of carcinogens?
They can be divided into three major categories: chemical carcinogens (including those from biological sources), physical carcinogens, and oncogenic (cancer-causing) viruses.
What are the stages of carcinogenesis?
Carcinogenesis can be divided conceptually into four steps: tumor initiation, tumor promotion, malignant conversion, and tumor progression (Figure 17-1). The distinction between initiation and promotion was recognized through studies involving both viruses and chemical carcinogens.
What are some examples of carcinogens?
Pollution & Exposure to Chemicals A few well-known carcinogens are asbestos, nickel, cadmium, radon, vinyl chloride, benzidene, and benzene. These carcinogens may act alone or with another carcinogen to increase your risk. For example, asbestos workers who also smoke have a higher risk of lung cancer.
What are 3 examples of carcinogens?
Exposure to some chemicals and hazardous substances can increase the risk of cancer. A few well-known carcinogens are asbestos, nickel, cadmium, radon, vinyl chloride, benzidene, and benzene. These carcinogens may act alone or with another carcinogen to increase your risk.
What are types of radiation?
Now, let’s look at the different kinds of radiation. There are four major types of radiation: alpha, beta, neutrons, and electromagnetic waves such as gamma rays. They differ in mass, energy and how deeply they penetrate people and objects. The first is an alpha particle.
What are the three steps of carcinogenesis?
The three-stage theory of carcinogenesis is one of the most common explanations for the development of cancer. This theory divides cancer development into three stages: initiation, promo- tion, and progression.
What are three types of carcinogens?
What are carcinogenic effects?
Carcinogens may increase the risk of cancer by altering cellular metabolism or damaging DNA directly in cells, which interferes with biological processes, and induces the uncontrolled, malignant division, ultimately leading to the formation of tumors.
What are the causes of radiation?
Background radiation is emitted from both naturally occurring and man-made sources. Natural sources include cosmic radiation, radon, radiation in the body, solar radiation and external terrestrial radiation. Man-made forms of radiation are used in X-rays, cancer treatment, nuclear facilities and nuclear weapons.
What are the 7 types of radiation?
The electromagnetic spectrum is generally divided into seven regions, in order of decreasing wavelength and increasing energy and frequency. The common designations are radio waves, microwaves, infrared (IR), visible light, ultraviolet (UV) light, X-rays and gamma-rays.