are cannabinoids effective on cancers?

Cannabinoids are naturally compounds found in cannabis sativa or endogenously produced in mammals, birds, reptiles and fish. the production of cannabinoids for different purposes including oil-seed and fiber production had already commenced around 4000 bc. at least 113 forms of cannabinoids have been extracted from cannabis plant material. the most well-known compounds are δ9-tetrahydrocannabinol, cannabidiol and cannabinol (1). there are some reported side effects for cannabinoid consumption including increasing the time of sleep with lower quality, effects on cognition and some neurological disorders. following search in pub med (132 articles) and google scholar (9 articles) databases between 2010 to 2020, it was found that they are effective in the treatment of lung, colorectal, prostate, breast, pancreas, and hepatic cancers. the effectiveness of natural and synthetic cannabinoids mediated by cannabinoid receptors (type 1 and 2, vanilloid receptors) has been documented. another recently recognized receptor for cannabinoid effects is cb3 which is expressed in entire body (2). there are close association between the up-regulation of cb3 and the incidence of melanoma and colorectal cancer (3). there are increasing and convincing data on effectiveness of cannabinoids in treatment of various cancers and still additional well-designed in vivo preclinical and clinical trials should be performed. at the same time, the regulatory processes should be also established.