title: Orthotopic expression of human 15-lipoxygenase (LO)-1 in the dorsolateral prostate of normal wild-type C57BL/6 mouse causes PIN-like lesions.
abstract: The lipid-peroxidating enzyme, 15-lipoxygenase (LO)-1 and its metabolite, 13-S-hydroxyoctadecadienoic acid (13-S-HODE), likely contribute to prostate tumorigenesis. Thus, this study evaluated adenovirus-mediated overexpression of 15-LO-1 on normal mouse prostate. Adenovirus expressing either human 15-LO-1 tagged with green fluorescent protein (GFP) or GFP alone was orthotopically injected into the dorsolateral prostates of C57BL/6 mice, three times over the course of 60 days. On day 90, pathological changes in prostate tissue were assessed by hematoxylin and eosin (H&E) staining. Expression of the proliferation marker Ki-67 was evaluated by immunohistochemistry and expression of angiogenesis markers were analyzed by an antibody array. Based on the latter study, immunoprecipitation analysis was used to measure the effect of 13-S-HODE, with or without conditioned media, on fibroblast growth factor-a and b (FGF-a and FGF-b) expression in human PrEC (normal prostate epithelial), PrSMC (normal prostate smooth muscle) and PrSC (normal prostate stromal) lines. Expression of viral 15-LO-1-GFP, but not GFP alone, resulted in the development of a prostate intraepithelial neoplasia (PIN)-like phenotype with increased expression of Ki-67. Aberrant 15-LO-1 expression also induced the angiogenic markers FGF-a and FGF-b. Human PrEC, PrSMC and PrSC lines demonstrated an increase in FGF-b expression upon stimulation with 13-S-HODE, which was further increased by the addition of conditioned media from the epithelial or smooth muscle cells. Using adenoviral mediated 15-LO-1 gene delivery, this study suggests that aberrant 15-LO-1 overexpression in normal prostate can trigger events leading to prostate epithelial and stromal cell proliferation. Thus, our findings demonstrate the effectiveness of this viral system for 15-LO-1 expression studies in tissues.
authors.affiliation: Department of Urology, University of Pittsburgh and Cancer Institute, PA 15232, USA.
authors.forename: Malabika
authors.initials: M
authors.lastname: Sen
authors.forename: Kevin
authors.initials: K
authors.lastname: McHugh
authors.forename: Justin
authors.initials: J
authors.lastname: Hutzley
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Philips
authors.forename: Rajiv
authors.initials: R
authors.lastname: Dhir
authors.forename: Anil V
authors.initials: AV
authors.lastname: Parwani
authors.forename: Uddhav P
authors.initials: UP
authors.lastname: Kelavkar
mesh_terms: D000256:Adenoviridae / Q000235:genetics / Q000378:metabolism; D000818:Animals; D001093:Arachidonate 15-Lipoxygenase / Q000235:genetics / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D002460:Cell Line; D006801:Humans; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism*; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009389:Neovascularization, Pathologic; D011467:Prostate / Q000033:anatomy & histology / Q000378:metabolism / Q000473:pathology; D011471:Prostatic Neoplasms / Q000378:metabolism / Q000473:pathology; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D015415:Biomarkers; D007527:Isoenzymes; D019394:Ki-67 Antigen; C498355:Mki67 protein, mouse; D011993:Recombinant Fusion Proteins; D001093:Arachidonate 15-Lipoxygenase