title: Enhanced anti-tumor effects of combined MDR1 RNA interference and human sodium/iodide symporter (NIS) radioiodine gene therapy using an adenoviral system in a colon cancer model.
abstract: Using an adenoviral system as a delivery mediator of therapeutic gene, we investigated the therapeutic effects of the use of combined MDR1 shRNA and human NIS (hNIS) radioiodine gene therapy in a mouse colon xenograft model. In vitro uptake of Tc-99m sestamibi was increased approximately two-fold in cells infected with an adenovirus vector that expressed MDR1 shRNA (Ad-shMDR1) and I-125 uptake was 25-fold higher in cells infected with an adenovirus vector that expressed human NIS (Ad-hNIS) as compared with control cells. As compared with doxorubicin or I-131 treatment alone, the combination of doxorubicin and I-131 resulted in enhanced cytotoxicity for both Ad-shMDR1- and Ad-hNIS-infected cells, but not for control cells. In vivo uptake of Tc-99m sestamibi and Tc-99m pertechnetate was twofold and 10-fold higher for Ad-shMDR1 and Ad-hNIS-infected tumors as compared with tumors infected with a control adenovirus construct that expressed beta-galactosidase (Ad-LacZ), respectively. In mice treated with either doxorubicin or I-131 alone, there was a slight delay in tumor growth as compared to mice treated with Ad-LacZ. However, combination therapy with doxorubicin and I-131 induced further significant inhibition of tumor growth as compared with mice treated with Ad-LacZ. We have shown successful therapeutic efficacy of combined MDR shRNA and hNIS radioiodine gene therapy using an adenoviral vector system in a mouse colon cancer model. Adenovirus-mediated cancer gene therapy using MDR1 shRNA and hNIS would be a useful tool for the treatment of cancer cells expressing multi-drug resistant genes.
authors.affiliation: Department of Nuclear Medicine, School of Medicine, Kyungpook National University, Daegu, Korea.
authors.forename: S J
authors.initials: SJ
authors.lastname: Ahn
authors.forename: Y H
authors.initials: YH
authors.lastname: Jeon
authors.forename: Y J
authors.initials: YJ
authors.lastname: Lee
authors.forename: Y L
authors.initials: YL
authors.lastname: Lee
authors.forename: S-W
authors.initials: SW
authors.lastname: Lee
authors.forename: B-C
authors.initials: BC
authors.lastname: Ahn
authors.forename: J-H
authors.initials: JH
authors.lastname: Ha
authors.forename: J
authors.initials: J
authors.lastname: Lee
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics*; D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000235:genetics / Q000473:pathology / Q000628:therapy* / Q000821:virology; D003131:Combined Modality Therapy; D004317:Doxorubicin / Q000493:pharmacokinetics / Q000494:pharmacology; D018432:Drug Resistance, Multiple; D015316:Genetic Therapy / Q000379:methods*; D006801:Humans; D007457:Iodine Radioisotopes / Q000493:pharmacokinetics / Q000627:therapeutic use; D051379:Mice; D008819:Mice, Nude; D034622:RNA Interference; D027981:Symporters / Q000235:genetics* / Q000378:metabolism; D014162:Transfection; D023041:Xenograft Model Antitumor Assays; D000099209:Sodium-Iodide Symporters
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D004317:Doxorubicin; D007457:Iodine Radioisotopes; D027981:Symporters; D000099209:Sodium-Iodide Symporters