title: Cannabinoid CB₁ receptor is downregulated in clear cell renal cell carcinoma.
abstract: Several studies in cell cultures and in animal models have demonstrated that cannabinoids have important antitumoral properties. Because many of these effects are mediated through cannabinoid (CB) receptors CB₁ and CB₂, the study of their expression in human neoplasms has become of great interest in recent years. Fresh and formalin-fixed tissue samples of 20 consecutive clear cell renal cell carcinomas (CCRCCs) were collected prospectively and analyzed for the expression of both CB receptors by using RT-PCR, Western blot (WB), and immunohistochemical techniques. RT-PCR assays demonstrated the expression of mRNA encoding the CB₁ in tumor tissue and in adjacent non-neoplastic kidney. Conversely, WB and IHC revealed a marked downregulation of CB₁ protein in tumor tissue; CB₂ was not expressed. The obtained data suggest a possible implication of the endocannabinoid system in renal carcinogenesis. A posttranscriptional downregulation of CB₁ and the absence of expression of CB₂ characterize CCRCC.
authors.affiliation: Department of Physiology, Faculty of Medicine and Dentistry, University of the Basque Country, Universidad del País Vasco/Euskal Herriko Unibertsitatea (UPV/EHU), Leioa, Bizkaia, Spain.
authors.forename: Gorka
authors.initials: G
authors.lastname: Larrinaga
authors.forename: Begoña
authors.initials: B
authors.lastname: Sanz
authors.forename: Itxaro
authors.initials: I
authors.lastname: Pérez
authors.forename: Lorena
authors.initials: L
authors.lastname: Blanco
authors.forename: María L
authors.initials: ML
authors.lastname: Cándenas
authors.forename: Francisco M
authors.initials: FM
authors.lastname: Pinto
authors.forename: Javier
authors.initials: J
authors.lastname: Gil
authors.forename: José I
authors.initials: JI
authors.lastname: López
mesh_terms: D015153:Blotting, Western; D002292:Carcinoma, Renal Cell / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation / Q000235:genetics; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007680:Kidney Neoplasms / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000235:genetics; D043884:Receptor, Cannabinoid, CB1 / Q000235:genetics* / Q000378:metabolism*; D043885:Receptor, Cannabinoid, CB2 / Q000235:genetics* / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D012333:RNA, Messenger; D043884:Receptor, Cannabinoid, CB1; D043885:Receptor, Cannabinoid, CB2