CB2 cannabinoid receptor activation promotes colon cancer progression via AKT/GSK3β signaling pathway

Abstract

The pharmacological activation of the cannabinoid receptor type 2, CB2, has been shown to elicit anti-tumoral mechanisms in different cancer types. However, little is known about its endogenous role in tumor pathophysiology, and different studies have attributed pro-tumorigenic properties to this receptor. In a previous work, we showed that CB2 expression is a poor prognostic factor in colon cancer patients. Here we report that activation of CB2 with low doses of specific agonists induce cell proliferation and favor the acquisition of aggressive molecular features in colon cancer cells. We show that sub-micromolar concentrations of CB2-specific agonists, JWH-133 and HU-308, promote an increase in cell proliferation rate through the activation of AKT/PKB pathway in colon cancer in vitro and in vivo. AKT activation promotes GSK3β inhibition and thus, a more aggressive cell phenotype with the subsequent elevation of SNAIL levels, E-cadherin degradation and β-catenin delocalization from cell membrane. Taken together, our data show that CB2 activation with sub-micromolar doses of agonists, which could be more similar to endogenous levels of cannabinoids, promote colon cancer progression, implicating that CB2 could have a pro-tumorigenic endogenous role in colon cancer.

The Trouble with CBD Oil

“…This is certainly exciting news, and research is ongoing around the world, but there is no solid clinical evidence yet to support that cannabinoids -whether natural or synthetic -can effectively and safely treat cancer in actual humans [17]. In fact, there are indications that certain types of cancer may even accelerate when exposed to cannabinoids [18]. This becomes problematic when patients choose to refuse chemotherapy treatment because they firmly believe in the rumored curative properties of cannabinoids.…”

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