title: Insertion of the human sodium iodide symporter to facilitate deep tissue imaging does not alter oncolytic or replication capability of a novel vaccinia virus.
abstract: BACKGROUND
  Oncolytic viruses show promise for treating cancer. However, to assess therapeutic efficacy and potential toxicity, a noninvasive imaging modality is needed. This study aimed to determine if insertion of the human sodium iodide symporter (hNIS) cDNA as a marker for non-invasive imaging of virotherapy alters the replication and oncolytic capability of a novel vaccinia virus, GLV-1h153.
  
  
  METHODS
  GLV-1h153 was modified from parental vaccinia virus GLV-1h68 to carry hNIS via homologous recombination. GLV-1h153 was tested against human pancreatic cancer cell line PANC-1 for replication via viral plaque assays and flow cytometry. Expression and transportation of hNIS in infected cells was evaluated using Westernblot and immunofluorescence. Intracellular uptake of radioiodide was assessed using radiouptake assays. Viral cytotoxicity and tumor regression of treated PANC-1tumor xenografts in nude mice was also determined. Finally, tumor radiouptake in xenografts was assessed via positron emission tomography (PET) utilizing carrier-free 124I radiotracer.
  
  
  RESULTS
  GLV-1h153 infected, replicated within, and killed PANC-1 cells as efficiently as GLV-1h68. GLV-1h153 provided dose-dependent levels of hNIS expression in infected cells. Immunofluorescence detected transport of the protein to the cell membrane prior to cell lysis, enhancing hNIS-specific radiouptake (P < 0.001). In vivo, GLV-1h153 was as safe and effective as GLV-1h68 in regressing pancreatic cancer xenografts (P < 0.001). Finally, intratumoral injection of GLV-1h153 facilitated imaging of virus replication in tumors via 124I-PET.
  
  
  CONCLUSIONS
  Insertion of the hNIS gene does not hinder replication or oncolytic capability of GLV-1h153, rendering this novel virus a promising new candidate for the noninvasive imaging and tracking of oncolytic viral therapy.
authors: Department of Biochemistry, University of Wuerzburg, Wuerzburg D-97074, Germany.
authors: Dana
authors: D
authors: Haddad
authors: Nanhai G
authors: NG
authors: Chen
authors: Qian
authors: Q
authors: Zhang
authors: Chun-Hao
authors: CH
authors: Chen
authors: Yong A
authors: YA
authors: Yu
authors: Lorena
authors: L
authors: Gonzalez
authors: Susanne G
authors: SG
authors: Carpenter
authors: Joshua
authors: J
authors: Carson
authors: Joyce
authors: J
authors: Au
authors: Arjun
authors: A
authors: Mittra
authors: Mithat
authors: M
authors: Gonen
authors: Pat B
authors: PB
authors: Zanzonico
authors: Yuman
authors: Y
authors: Fong
authors: Aladar A
authors: AA
authors: Szalay
mesh_terms: D000818:Animals; D015153:Blotting, Western; D016923:Cell Death; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D005434:Flow Cytometry; D005786:Gene Expression Regulation; D005822:Genetic Vectors / Q000235:genetics; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D007457:Iodine Radioisotopes; D051379:Mice; D016254:Mutagenesis, Insertional / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis; D050504:Oncolytic Viruses / Q000502:physiology*; D049268:Positron-Emission Tomography; D021381:Protein Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D027981:Symporters / Q000235:genetics* / Q000378:metabolism; D014616:Vaccinia virus / Q000502:physiology*; D014779:Virus Replication / Q000502:physiology*; D023041:Xenograft Model Antitumor Assays; D000099209:Sodium-Iodide Symporters
chemical_list: D049452:Green Fluorescent Proteins; D007457:Iodine Radioisotopes; D012333:RNA, Messenger; D027981:Symporters; D000099209:Sodium-Iodide Symporters