A metabolically stable analog of anandamide was shown to suppress cancer growth in cell lines derived from thyroid carcinomas. This was through the stimulation of apoptosis. High levels of CB1 expression was responsible for this growth suppression (Cozzolino et al., 2010).
Another study showed that basic fibroblast growth factor-stimulated endothelial cell proliferation was suppressed by the metabolically stable anandamide analog, 2-methyl-2′-F-anandamide (Met-F-AEA), in a dose-dependent manner. Furthermore, Met-F-AEA was shown to help induce apoptosis, both effects dependent on cannabinoid CB1 receptor stimulation (Pisanti et al., 2007).
Met-F-AEA addition led to blocking of endocannabinoid reuptake, increasing endocannabinoid levels in athymic mice with rat thyroid tumor xenografts. Furthermore, it was suggested that Met-F-AEA may help in suppressing tumor growth via CB1 (Bifulco et al., 2001, 2004). The same Met-F-AEA was also shown to help suppress thyroid cancer metastasis in a CB1-dependent way (Portella et al., 2003).
Apoptosis and sensitivity to the chemotherapeutic drug paclitaxel were increased by boosting CB2 expression in the ARO cell line of the most aggressive type of thyroid cancer, anaplastic thyroid carcinoma. In nude mice overexpressing CB2 in thyroid cancer xenografts, considerable tumor regression was triggered by stimulation with CB2. This proposes that CB2 may serve as a feasible therapeutic target for the treatment of anaplastic thyroid carcinoma (Shi et al., 2008).
In another study, it was shown that CB1 and CB2 expression was significantly increased in malignant thyroid lesions compared to benign thyroid lesions. Furthermore, increased expression of CB2 was shown to be connected to lymph node metastases. This proposes that CB receptors may play a role in malignant thyroid transformation and particularly CB2 receptors may be used as a good biomarker and potential therapeutic target for the treatment of thyroid cancer (Lakiotaki et al., 2015).
Further, it was shown that in a rat thyroid cancer cell line, cancer cell growth was suppressed by several plant cannabinoids and cannabis extracts (Ligresti et al., 2006).