title: Oncolytic tanapoxvirus expressing FliC causes regression of human colorectal cancer xenografts in nude mice.
abstract: Colorectal cancers are significant causes of morbidity and mortality and existing therapies often perform poorly for individuals afflicted with advanced disease. Oncolytic virotherapy is an emerging therapeutic modality with great promise for addressing this medical need. Herein we describe the in vivo testing of recombinant variants of the tanapoxvirus (TPV). Recombinant viruses were made ablated for either the 66R gene (encoding a thymidine kinase), the 2L gene (encoding a TNF-binding protein), or both. Some of the recombinants were armed to express mouse chemotactic protein 1 (mCCL2/mMCP-1), mouse granulocyte-monocyte colony stimulating factor (mGM-CSF), or bacterial flagellin (FliC). Tumors were induced in athymic nude mice by implantation of HCT 116 cells and subsequently treated by a single intratumoral injection of one of the recombinant TPVs. Histological examination showed a common neoplastic cell type and a range of immune cell infiltration, necrosis, and tumor cell organization. Significant regression was seen in tumors treated with virus TPV/Δ2L/Δ66R/fliC, and to a lesser extent the recombinants TPV/Δ2L and TPV/Δ66R. Our results suggest that oncolytic recombinants of the TPV armed with activators of the innate immune response may be effective virotherapeutic agents for colorectal cancers in humans and should be explored further to fully realize their potential.
authors.affiliation: Laboratory of Virology, Department of Biological Sciences, Western Michigan University, Kalamazoo, MI, 49008, USA. steven.j.conrad@wmich.edu.
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Conrad
authors.affiliation: Laboratory of Virology, Department of Biological Sciences, Western Michigan University, Kalamazoo, MI, 49008, USA. mohamed.a.elswad@wmich.edu.
authors.forename: Mohamed
authors.initials: M
authors.lastname: El-Aswad
authors.affiliation: Laboratory of Virology, Department of Biological Sciences, Western Michigan University, Kalamazoo, MI, 49008, USA. esaw.kurban@wmich.edu.
authors.forename: Esaw
authors.initials: E
authors.lastname: Kurban
authors.affiliation: Laboratory of Virology, Department of Biological Sciences, Western Michigan University, Kalamazoo, MI, 49008, USA. david.jeng@wmich.edu.
authors.forename: David
authors.initials: D
authors.lastname: Jeng
authors.affiliation: Laboratory of Virology, Department of Biological Sciences, Western Michigan University, Kalamazoo, MI, 49008, USA. brian.tripp@wmich.edu.
authors.forename: Brian C
authors.initials: BC
authors.lastname: Tripp
authors.affiliation: Laboratory of Virology, Department of Biological Sciences, Western Michigan University, Kalamazoo, MI, 49008, USA. charles.s.nutting@wmich.edu.
authors.forename: Charles
authors.initials: C
authors.lastname: Nutting
authors.affiliation: Laboratory of Virology, Department of Biological Sciences, Western Michigan University, Kalamazoo, MI, 49008, USA. rob.eversole@wmich.edu.
authors.forename: Robert
authors.initials: R
authors.lastname: Eversole
authors.affiliation: Department of Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, Michigan, USA. mackenz8@msu.edu.
authors.forename: Charles
authors.initials: C
authors.lastname: Mackenzie
authors.affiliation: Laboratory of Virology, Department of Biological Sciences, Western Michigan University, Kalamazoo, MI, 49008, USA. karim.essani@wmich.edu.
authors.forename: Karim
authors.initials: K
authors.lastname: Essani
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000473:pathology* / Q000628:therapy; D004195:Disease Models, Animal; D005408:Flagellin / Q000235:genetics*; D015870:Gene Expression; D015316:Genetic Therapy; D005822:Genetic Vectors / Q000008:administration & dosage / Q000235:genetics*; D006801:Humans; D008297:Male; D051379:Mice; D050130:Oncolytic Virotherapy; D050504:Oncolytic Viruses / Q000235:genetics*; D014161:Transduction, Genetic; D019076:Transgenes; D023041:Xenograft Model Antitumor Assays; D018158:Yatapoxvirus / Q000235:genetics*
chemical_list: D005408:Flagellin