title: Association between cannabinoid CB₁ receptor expression and Akt signalling in prostate cancer.
abstract: BACKGROUND
  In prostate cancer, tumour expression of cannabinoid CB₁ receptors is associated with a poor prognosis. One explanation for this association comes from experiments with transfected astrocytoma cells, where a high CB receptor expression recruits the Akt signalling survival pathway. In the present study, we have investigated the association between CB₁ receptor expression and the Akt pathway in a well-characterised prostate cancer tissue microarray.
  
  
  RESULTS
  Phosphorylated Akt immunoreactivity (pAkt-IR) scores were available in the database. CB₁ receptor immunoreactivity (CB₁IR) was rescored from previously published data using the same scale as pAkt-IR. There was a highly significant correlation between CB₁IR and pAkt-IR. Further, cases with high expression levels of both biomarkers were much more likely to have a more severe form of the disease at diagnosis than those with low expression levels. The two biomarkers had additive effects, rather than an interaction, upon disease-specific survival.
  
  
  CONCLUSIONS
  The present study provides data that is consistent with the hypothesis that at a high CB₁ receptor expression, the Akt signalling pathway becomes operative.
authors.affiliation: Pharmacology, Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå, Sweden.
authors.forename: Mariateresa
authors.initials: M
authors.lastname: Cipriano
authors.forename: Jenny
authors.initials: J
authors.lastname: Häggström
authors.forename: Peter
authors.initials: P
authors.lastname: Hammarsten
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Fowler
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D045744:Cell Line, Tumor; D066246:ErbB Receptors / Q000378:metabolism; D015870:Gene Expression; D006801:Humans; D053208:Kaplan-Meier Estimate; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D010750:Phosphoproteins / Q000378:metabolism; D016016:Proportional Hazards Models; D011467:Prostate / Q000378:metabolism / Q000473:pathology; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D011499:Protein Processing, Post-Translational; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D043884:Receptor, Cannabinoid, CB1 / Q000235:genetics / Q000378:metabolism*; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000378:metabolism; D015398:Signal Transduction; D046888:Tissue Array Analysis
chemical_list: D066246:ErbB Receptors; D019394:Ki-67 Antigen; D010750:Phosphoproteins; D051057:Proto-Oncogene Proteins c-akt; D043884:Receptor, Cannabinoid, CB1; D018719:Erb-b2 Receptor Tyrosine Kinases; C512478:EGFR protein, human; C508053:ERBB2 protein, human