title: Bladder cancer cell growth and motility implicate cannabinoid 2 receptor-mediated modifications of sphingolipids metabolism.
abstract: The inhibitory effects demonstrated by activation of cannabinoid receptors (CB) on cancer proliferation and migration may also play critical roles in controlling bladder cancer (BC). CB expression on human normal and BC specimens was tested by immunohistochemistry. Human BC cells RT4 and RT112 were challenged with CB agonists and assessed for proliferation, apoptosis, and motility. Cellular sphingolipids (SL) constitution and metabolism were evaluated after metabolic labelling. CB1-2 were detected in BC specimens, but only CB2 was more expressed in the tumour. Both cell lines expressed similar CB2. Exposure to CB2 agonists inhibited BC growth, down-modulated Akt, induced caspase 3-activation and modified SL metabolism. Baseline SL analysis in cell lines showed differences linked to unique migratory behaviours and cytoskeletal re-arrangements. CB2 activation changed the SL composition of more aggressive RT112 cells by reducing (p < 0.01) Gb3 ganglioside (-50 ± 3%) and sphingosine 1-phosphate (S1P, -40 ± 4%), which ended up to reduction in cell motility (-46 ± 5%) with inhibition of p-SRC. CB2-selective antagonists, gene silencing and an inhibitor of SL biosynthesis partially prevented CB2 agonist-induced effects on cell viability and motility. CB2 activation led to ceramide-mediated BC cell apoptosis independently of SL constitutive composition, which instead was modulated by CB2 agonists to reduce cell motility.
authors.affiliation: Division of Experimental Oncology/Unit of Urology; URI; IRCCS Ospedale San Raffaele, Milan, Italy.
authors.forename: Arianna
authors.initials: A
authors.lastname: Bettiga
authors.affiliation: Department of Medical Biotechnology and Translational Medicine, University of Milano, Segrate, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Aureli
authors.affiliation: Division of Experimental Oncology/Unit of Urology; URI; IRCCS Ospedale San Raffaele, Milan, Italy.
authors.forename: Giorgia
authors.initials: G
authors.lastname: Colciago
authors.affiliation: Department of Medical Biotechnology and Translational Medicine, University of Milano, Segrate, Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: Murdica
authors.affiliation: Division of Experimental Oncology/Unit of Urology; URI; IRCCS Ospedale San Raffaele, Milan, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Moschini
authors.affiliation: Division of Experimental Oncology/Unit of Urology; URI; IRCCS Ospedale San Raffaele, Milan, Italy.|Department of Pathology, IRCCS Ospedale San Raffaele, Milan, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Lucianò
authors.affiliation: Department of Medicine, University of Stony Brook, Stony Brook, New York 11794, USA.
authors.forename: Daniel
authors.initials: D
authors.lastname: Canals
authors.affiliation: Department of Medicine, University of Stony Brook, Stony Brook, New York 11794, USA.
authors.forename: Yusuf
authors.initials: Y
authors.lastname: Hannun
authors.affiliation: Division of Experimental Oncology/Unit of Urology; URI; IRCCS Ospedale San Raffaele, Milan, Italy.|Department of Clinical Pharmacology, Linköping University, Sweden.
authors.forename: Petter
authors.initials: P
authors.lastname: Hedlund
authors.affiliation: Division of Experimental Oncology/Unit of Urology; URI; IRCCS Ospedale San Raffaele, Milan, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Lavorgna
authors.affiliation: Division of Experimental Oncology/Unit of Urology; URI; IRCCS Ospedale San Raffaele, Milan, Italy.
authors.forename: Renzo
authors.initials: R
authors.lastname: Colombo
authors.affiliation: Department of Medical Biotechnology and Translational Medicine, University of Milano, Segrate, Italy.
authors.forename: Rosaria
authors.initials: R
authors.lastname: Bassi
authors.affiliation: Department of Medical Biotechnology and Translational Medicine, University of Milano, Segrate, Italy.
authors.forename: Maura
authors.initials: M
authors.lastname: Samarani
authors.affiliation: Division of Experimental Oncology/Unit of Urology; URI; IRCCS Ospedale San Raffaele, Milan, Italy.|Università Vita-Salute San Raffaele, Milan, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Montorsi
authors.affiliation: Università Vita-Salute San Raffaele, Milan, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Salonia
authors.affiliation: Division of Experimental Oncology/Unit of Urology; URI; IRCCS Ospedale San Raffaele, Milan, Italy.
authors.forename: Fabio
authors.initials: F
authors.lastname: Benigni
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D001681:Biological Assay; D063386:Cannabinoid Receptor Agonists / Q000494:pharmacology; D063387:Cannabinoid Receptor Antagonists / Q000494:pharmacology; D002295:Carcinoma, Transitional Cell / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D053148:Caspase 3 / Q000235:genetics / Q000378:metabolism; D002460:Cell Line; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D051057:Proto-Oncogene Proteins c-akt / Q000235:genetics / Q000378:metabolism; D043884:Receptor, Cannabinoid, CB1 / Q000235:genetics* / Q000378:metabolism; D043885:Receptor, Cannabinoid, CB2 / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction; D013107:Sphingolipids / Q000378:metabolism*; D001749:Urinary Bladder Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D014945:Wound Healing / Q000187:drug effects; D019061:src-Family Kinases / Q000235:genetics / Q000378:metabolism
chemical_list: C588309:CNR2 protein, human; D063386:Cannabinoid Receptor Agonists; D063387:Cannabinoid Receptor Antagonists; D043884:Receptor, Cannabinoid, CB1; D043885:Receptor, Cannabinoid, CB2; D013107:Sphingolipids; D019061:src-Family Kinases; D051057:Proto-Oncogene Proteins c-akt; C505407:CASP3 protein, human; D053148:Caspase 3