The potential of CB2 antagonists as a target for treating cancer (Xiang et al., 2018) and liver fibrosis (Mallat et al., 2013) and of CB2 receptor agonists in the treatment of neuropathic pain, neuroinflammation, and neurodegenerative disorders (Guindon and Hohmann, 2008; Lunn et al., 2008; Racz et al., 2008a, b; Contino et al., 2017) hint to the need of molecular insights into the activation mechanism of CB2. This evidence concerns the gene CNR2 and cancer.