Cannabinoid-based Anti-cancer Strategies: Slowly Approaching the Bedside

Modulation of the endocannabinoid system has emerged as a potential therapeutic strategy for the treatment of diverse types of cancer and related pathologies. Thus far, the use of specific cannabinoids has been primarily approved for the management of chemotherapy-induced side effects. Palliative actions of cannabinoids include the control of nausea and vomiting, pain alleviation and appetite stimulation. Moreover, a growing body of research has exposed the anticarcinogenic potential of cannabinoids. In vitro and in vivo studies have shown that endogenous, plant-derived and synthetic cannabinoids can effectively modulate tumor growth in diverse cancer models. Although this has not yet reached the bedside, ongoing clinical trials and research efforts may approach cannabinoid-based antitumor therapies to cancer patients in the near future.

So far, studies on cannabinoids as antitumor agents have been mainly focused on understanding the mechanism of action of well-known phytocannabinoids such as Δ9-THC or CBD. However, novel cannabinoids with antitumor properties are also emerging in the literature. In this chapter, we aim to provide an updated overview of the therapeutic potential of cannabinoids in cancer. We will comprehensively summarize the diverse cannabinoid structures exerting antitumor properties analyzing the molecular basis of these actions. Recent and ongoing clinical trials will be considered to provide a deeper insight into the current scenario of cannabinoids in oncology.

Keywords: Apoptosis, Cancer, Cannabinoids, CB1R, CB2R, Chemotherapy, Clinical trials, Endocannabinoid system, GPR55, Palliative effects.