Anticarcinogen
Encyclopedia
An anticarcinogen is any chemical which reduces the occurrence of cancer
s, reduces the severity of cancers that do occur, or acts against cancers that do occur, based on evidence from in vitro
studies, animal models, epidemiological studies and/or clinical studies.
Preventative anticarcinogens act by enhancing an organism's natural defenses against cancer, by deactivating carcinogen
s or by blocking the mechanisms by which carcinogens act (such as free radical damage to DNA
).
Anticarcinoma agents participate in the selective destruction of cancer cells, or inhibit the growth and proliferation of cancer cells. See also: Chemotherapy
.
Interest in preventative anticarcinogens is motivated primarily by the principle that it is preferable to prevent disease where possible, and that positive actions can be effective as well as negative ones (such as reducing exposure to known carcinogen
s). Anticarcinoma agents that do not have significant negative side effects have a similar potential role, by reducing the seriousness of any cancers that do occur.
s and flavonoid
s is anticarcinogenic. Interest in many popular nutritional supplements, including essential antioxidant
nutrients such as selenium
compounds and hormones such as melatonin
and DHEA, is partly motivated by evidence that these have significant anticarcinogenic effects in appropriate quantities. The major psychoactive component in marijuana, tetrahydrocannabinol
, has been shown to have anticarcinogenic activity, when injected into mice. The other major component of cannabis
- cannabidiol
, has also been shown to inhibit cancer cell growth, with low potency in non-cancer cells. Although the inhibitory mechanism is not yet fully understood, Ligresti et al. suggest that "cannabidiol exerts its effects on these cells through a combination of mechanisms that include either direct or indirect activation of CB2 and TRPV1
receptors, and induction of oxidative stress
, all contributing to induce apoptosis
.".
Cancer
Cancer , known medically as a malignant neoplasm, is a large group of different diseases, all involving unregulated cell growth. In cancer, cells divide and grow uncontrollably, forming malignant tumors, and invade nearby parts of the body. The cancer may also spread to more distant parts of the...
s, reduces the severity of cancers that do occur, or acts against cancers that do occur, based on evidence from in vitro
In vitro
In vitro refers to studies in experimental biology that are conducted using components of an organism that have been isolated from their usual biological context in order to permit a more detailed or more convenient analysis than can be done with whole organisms. Colloquially, these experiments...
studies, animal models, epidemiological studies and/or clinical studies.
Preventative anticarcinogens act by enhancing an organism's natural defenses against cancer, by deactivating carcinogen
Carcinogen
A carcinogen is any substance, radionuclide, or radiation that is an agent directly involved in causing cancer. This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes...
s or by blocking the mechanisms by which carcinogens act (such as free radical damage to DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
).
Anticarcinoma agents participate in the selective destruction of cancer cells, or inhibit the growth and proliferation of cancer cells. See also: Chemotherapy
Chemotherapy
Chemotherapy is the treatment of cancer with an antineoplastic drug or with a combination of such drugs into a standardized treatment regimen....
.
Interest in preventative anticarcinogens is motivated primarily by the principle that it is preferable to prevent disease where possible, and that positive actions can be effective as well as negative ones (such as reducing exposure to known carcinogen
Carcinogen
A carcinogen is any substance, radionuclide, or radiation that is an agent directly involved in causing cancer. This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes...
s). Anticarcinoma agents that do not have significant negative side effects have a similar potential role, by reducing the seriousness of any cancers that do occur.
Known anticarcinogens
There is epidemiological evidence that a diet rich in antioxidant vitaminVitamin
A vitamin is an organic compound required as a nutrient in tiny amounts by an organism. In other words, an organic chemical compound is called a vitamin when it cannot be synthesized in sufficient quantities by an organism, and must be obtained from the diet. Thus, the term is conditional both on...
s and flavonoid
Flavonoid
Flavonoids , are a class of plant secondary metabolites....
s is anticarcinogenic. Interest in many popular nutritional supplements, including essential antioxidant
Antioxidant
An antioxidant is a molecule capable of inhibiting the oxidation of other molecules. Oxidation is a chemical reaction that transfers electrons or hydrogen from a substance to an oxidizing agent. Oxidation reactions can produce free radicals. In turn, these radicals can start chain reactions. When...
nutrients such as selenium
Selenium
Selenium is a chemical element with atomic number 34, chemical symbol Se, and an atomic mass of 78.96. It is a nonmetal, whose properties are intermediate between those of adjacent chalcogen elements sulfur and tellurium...
compounds and hormones such as melatonin
Melatonin
Melatonin , also known chemically as N-acetyl-5-methoxytryptamine, is a naturally occurring compound found in animals, plants, and microbes...
and DHEA, is partly motivated by evidence that these have significant anticarcinogenic effects in appropriate quantities. The major psychoactive component in marijuana, tetrahydrocannabinol
Tetrahydrocannabinol
Tetrahydrocannabinol , also known as delta-9-tetrahydrocannabinol , Δ1-THC , or dronabinol, is the main chemical psychoactive substance found in the cannabis plant. It was first isolated in 1964. In pure form, it is a glassy solid when cold, and becomes viscous and sticky if warmed...
, has been shown to have anticarcinogenic activity, when injected into mice. The other major component of cannabis
Cannabis
Cannabis is a genus of flowering plants that includes three putative species, Cannabis sativa, Cannabis indica, and Cannabis ruderalis. These three taxa are indigenous to Central Asia, and South Asia. Cannabis has long been used for fibre , for seed and seed oils, for medicinal purposes, and as a...
- cannabidiol
Cannabidiol
Cannabidiol is a cannabinoid found in Cannabis. It is a major constituent of the plant, representing up to 40% in its extracts.It has displayed sedative effects in animal tests...
, has also been shown to inhibit cancer cell growth, with low potency in non-cancer cells. Although the inhibitory mechanism is not yet fully understood, Ligresti et al. suggest that "cannabidiol exerts its effects on these cells through a combination of mechanisms that include either direct or indirect activation of CB2 and TRPV1
TRPV1
The transient receptor potential cation channel subfamily V member 1 ', also known as the capsaicin receptor and the vanilloid receptor 1, is a protein that, in humans, is encoded by the TRPV1 gene...
receptors, and induction of oxidative stress
Oxidative stress
Oxidative stress represents an imbalance between the production and manifestation of reactive oxygen species and a biological system's ability to readily detoxify the reactive intermediates or to repair the resulting damage...
, all contributing to induce apoptosis
Apoptosis
Apoptosis is the process of programmed cell death that may occur in multicellular organisms. Biochemical events lead to characteristic cell changes and death. These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, and chromosomal DNA fragmentation...
.".