The cannabinoid 1 (CB1) and cannabinoid 2 (CB2) receptor agonist Δ9 -tetrahydrocannabinol (THC) has been shown to be a broad-range inhibitor of cancer in culture and in vivo, and is currently being used in a clinical trial for the treatment of glioblastoma. It has been suggested that other plant-derived cannabinoids, which do not interact efficiently with CB1 and CB2 receptors, can modulate the actions of Δ9 -THC. There are conflicting reports, however, as to what extent other cannabinoids can modulate Δ9 -THC activity, and most importantly, it is not clear whether other cannabinoid compounds can either potentiate or inhibit the actions of Δ9 -THC....
