Antiangiogenic activity of the endocannabinoid anandamide: correlation to its tumor-suppressor efficacy.
Endocannabinoids are now emerging as suppressors of key cell-signaling pathways involved in cancer cell growth, invasion, and metastasis. We have previously observed that the metabolically stable anandamide analog, 2-methyl-2'-F-anandamide (Met-F-AEA) can inhibit the growth of thyroid cancer in vivo. Our hypothesis was that the anti-tumor effect observed could be at least in part ascribed to inhibition of neo-angiogenesis. Therefore, the aim of this study was to assess the anti-angiogenic activity of Met-F-AEA, to investigate the molecular mechanisms underlying this effect and whether Met-F-AEA could antagonize tumor-induced endothelial cell sprouting. We show that Met-F-AEA inhibited bFGF-stimulated endothelial cell proliferation, in a dose-dependent manner, and also induced apoptosis, both effects reliant on cannabinoid CB1 receptor stimulation. Analyzing the signaling pathways implicated in angiogenesis, we observed that the bFGF-induced ERK phosphorylation was antagonized by Met-F-AEA, and we found that p38 MAPK was involved in Met-F-AEA-induced apoptosis. Moreover, Met-F-AEA was able to inhibit bi-dimensional capillary-like tube formation and activity of matrix metalloprotease MMP-2, a major matrix degrading enzyme. Importantly, we demonstrated that Met-F-AEA is also functional in vivo since it inhibited angiogenesis in the chick chorioallantoic neovascularization model. Finally, Met-F-AEA inhibited tumor-induced angiogenesis in a three-dimensional model of endothelial and thyroid tumor cell (KiMol) spheroids co-cultures in different 3-D polymeric matrices that resemble tumor microenvironment and architecture. Thus, our results suggest that anandamide could be involved in the control of cancer growth targeting both tumor cell proliferation and the angiogenic stimulation of the vasculature.
Pisanti
Simona
S
Department of Pharmaceutical Sciences, University of Salerno, Fisciano, Salerno, Italy.
Borselli
Cristina
C
Oliviero
Olimpia
O
Laezza
Chiara
C
Gazzerro
Patrizia
P
Bifulco
Maurizio
M
D020533:Angiogenesis Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology* / Q000627:therapeutic use; D017209:Apoptosis / Q000187:drug effects; D001095:Arachidonic Acids / Q000494:pharmacology* / Q000627:therapeutic use; D063385:Cannabinoid Receptor Modulators / Q000494:pharmacology* / Q000627:therapeutic use; D002454:Cell Differentiation / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002642:Chick Embryo; D049033:Chorioallantoic Membrane / Q000098:blood supply / Q000187:drug effects; D018920:Coculture Techniques; D004305:Dose-Response Relationship, Drug; D063388:Endocannabinoids; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D006801:Humans; D020935:MAP Kinase Signaling System / Q000187:drug effects; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D061965:Matrix Metalloproteinase Inhibitors; D009389:Neovascularization, Pathologic / Q000378:metabolism / Q000517:prevention & control*; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D053284:Polyunsaturated Alkamides / Q000494:pharmacology* / Q000627:therapeutic use; D051381:Rats; D043884:Receptor, Cannabinoid, CB1 / Q000819:agonists* / Q000378:metabolism; D018874:Spheroids, Cellular; D013552:Swine; D013964:Thyroid Neoplasms / Q000378:metabolism / Q000473:pathology
D020533:Angiogenesis Inhibitors; D000970:Antineoplastic Agents; D001095:Arachidonic Acids; D063385:Cannabinoid Receptor Modulators; D063388:Endocannabinoids; D061965:Matrix Metalloproteinase Inhibitors; D053284:Polyunsaturated Alkamides; D043884:Receptor, Cannabinoid, CB1; D016222:Fibroblast Growth Factor 2; D020778:Matrix Metalloproteinase 2; C078814:anandamide