In sporadic cancers, deficiencies in DNA repair are occasionally caused by a mutation in a DNA repair gene but are much more frequently caused by epigenetic alterations that reduce or silence expression of DNA repair genes. This is indicated in the figure at the 3rd level. Many studies of heavy metal-induced carcinogenesis show that such heavy metals cause a reduction in expression of DNA repair enzymes, some through epigenetic mechanisms. DNA repair inhibition is proposed to be a predominant mechanism in heavy metal-induced carcinogenicity. In addition, frequent epigenetic alterations of the DNA sequences code for small RNAs called microRNAs (or miRNAs). miRNAs do not code for proteins, but can "target" protein-coding genes and reduce their expression.
Cannabidiol (CBD) is one of dozens of non-psychoactive cannabinoids found in the hemp plant. Cannabidiol, and all the other cannabinoids, were patented by the United States Government in 2003 as neuroprotectants and antioxidants (Patent No. 6,630,507). Cannabinoids are characterized by their ability to act on the cannabinoid receptors that are found throughout the body. CBD and other cannabinoids are naturally occurring compounds that display potent anti-inflammatory and pain-relieving properties. They can promote the body’s healthy regulation of the central nervous, immune, and endocannabinoid systems.