title: Preclinical biodistribution and safety study of reduced expression in             immortalized cells/Dickkopf-3-encoding adenoviral vector for prostate cancer gene             therapy.
abstract: The biodistribution and safety of adenoviral vectors encoding the human REIC/Dkk-3 tumor suppressor gene (Ad-REIC) were examined in this preclinical study for in situ prostate cancer gene therapy. First, the in vitro apoptotic effects of Ad-REIC in normal and cancer cells derived from the prostate and liver were examined. Significant apoptotic effects were observed at 100 MOI (multiplicity of infection) in prostate cancer cells (LNCaP, PC3) and hepatoma cells (HEP3B and HEPG2); however, no effects were seen in normal cells. To analyze the safety of intraprostatic Ad-REIC administration, the biodistribution and histology after Ad-REIC injection were evaluated in various organs of normal male C57BL6 mice. In a supporting study, vector dissemination following intravenous injection of Ad-REIC into tail veins was determined. To evaluate whether Ad-REIC was present in the collected tissue specimens, human REIC gene detection was performed using DNA-PCR. Intraprostatic treatment administered at lower doses showed vector biodistribution into the colon, urinary bladder and prostate. At higher doses, vector dissemination was observed in tissues more distant from the prostate, including the lung, thymus, heart, liver and adrenal gland. After intravenous injection of Ad-REIC, dissemination was observed in the liver and spleen. These results indicate that the biodistribution of Ad-REIC is determined by the dose and route of administration. Although acute inflammatory effects were observed in the prostate after intraprostatic administration at higher doses, no abnormal histological findings were noted in the other tissues, including those of intravenously treated mice. Regarding the safety of Ad-REIC administration, no deaths and no signs of toxicity or unusual behavior were observed in the mice in any treatment group. Based on these preclinical experiments, adenovirus-mediated in situ REIC/Dkk-3 gene therapy is considered to be safe for use as a treatment for human prostate cancer.
authors.affiliation: Department of Urology, Okayama University, Okayama 700-8558,                     Japan.
authors.forename: Morito
authors.initials: M
authors.lastname: Sugimoto
authors.forename: Masami
authors.initials: M
authors.lastname: Watanabe
authors.forename: Haruki
authors.initials: H
authors.lastname: Kaku
authors.forename: Shun-Ai
authors.initials: SA
authors.lastname: Li
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Noguchi
authors.forename: Hideo
authors.initials: H
authors.lastname: Ueki
authors.forename: Masakiyo
authors.initials: M
authors.lastname: Sakaguchi
authors.forename: Nam-Ho
authors.initials: NH
authors.lastname: Huh
authors.forename: Yasutomo
authors.initials: Y
authors.lastname: Nasu
authors.forename: Hiromi
authors.initials: H
authors.lastname: Kumon
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000235:genetics / Q000628:therapy*; D045744:Cell Line, Tumor; D018925:Chemokines; D015316:Genetic Therapy / Q000009:adverse effects; D005822:Genetic Vectors / Q000009:adverse effects; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000096:biosynthesis / Q000235:genetics*; D008113:Liver Neoplasms / Q000235:genetics / Q000628:therapy*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D011471:Prostatic Neoplasms / Q000235:genetics / Q000628:therapy*; D014018:Tissue Distribution
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D018925:Chemokines; C498624:DKK3 protein, human; D036341:Intercellular Signaling Peptides and Proteins