The TLR4-Active Morphine Metabolite Morphine-3-Glucuronide Does Not Elicit Macrophage Classical Activation .
Fiche publication
Date publication
janvier 2016
Journal
Frontiers in pharmacology
Auteurs
Membres identifiés du Cancéropôle Est :
Dr GOUMON Yannick
Tous les auteurs :
Khabbazi S, Xie N, Pu W, Goumon Y, Parat MO
Lien Pubmed
Résumé
Macrophages are abundant in the tumor microenvironment where they adopt a pro-tumor phenotype following alternative polarization induced by paracrine factors from cancer and stromal cells. In contrast, classically activated macrophages have tumoricidal activities, such that the polarization of tumor-associated macrophages has become a novel therapeutic target. Toll-like receptor 4 engagement promotes classical activation of macrophages, and recent literature suggests TLR4 agonism to prevent metastasis and promote survival in experimental metastasis models. A growing number of studies indicate that TLR4 can respond to opioids, including the opioid receptor-inactive morphine metabolite morphine-3-glucuronide (M3G). We measured the activation of TLR4 in a reporter cell line exogenously expressing TLR4 and TLR4 co-receptors, and confirmed that M3G weakly but significantly activates TLR4. We hypothesized that M3G would promote the expression of classical activation signature genes in macrophages . We exposed mouse and human macrophage cell lines to M3G or the TLR4 activator lipopolysaccharide (LPS), alone or in combination with interferon gamma (IFN-γ). The classical macrophage activation markers tested were iNOS, CD86, IL-6, or TNF-α in RAW 264.7 cells and IL-6, IL-12, IL-23, TNF-α, CXCL10, and CXCL11 in THP1 cells. Our results show that despite exhibiting TLR4-activation ability, M3G does not elicit the expression of classical activation markers in LPS-responsive macrophages.
Référence
Front Pharmacol. 2016 ;7:441