title: DNA vaccine encoding HPV-16 E7 with mutation in L-Y-C-Y-E pRb-binding motif induces potent anti-tumor responses in mice.
abstract: Cervical cancer is the second most common cancer among women worldwide and remains a clinical problem despite improvements in early detection and therapy. The human papillomavirus (HPV) type 16 (HPV16) E7 oncoprotein expressed in cervical carcinoma cells are considered as attractive tumor-specific antigen targets for immunotherapy. Since the transformation potential of the oncogenes, vaccination based of these oncogenes is not safe. In present study, DNA vaccine expressing the modified variant with mutation in pRb-binding motif of the HPV-16 E7 oncoprotein was generated. A novel modified E7 gene with mutation in LYCYE motif was designed and constructed and the immunogenicity and antitumor effect of therapeutic DNA vaccines encoding the mutant and wild type of E7 gene were investigated. The L-Y-C-Y-E pRb-binding motif of E7 proteins has been involved in the immortalization and transformation of the host cell. The results showed that the mutant and wild type HPV-16 E7 vectors expressed the desired protein. Furthermore, the immunological mechanism behind mutant E7 DNA vaccine can be attributed at least partially to increased cytotoxic T lymphocyte, accompanied by the up-regulation of Th1-cytokine IFN-γ and TNF-β and down-regulation of Th3-cytokine TGF-β. Immunized mice with mutant plasmid demonstrated signiﬁcantly stronger cell immune responses and higher levels of tumor protection than wild-type E7 DNA vaccine. The results exhibit that modified E7 DNA vaccine may be a promising candidate for development of therapeutic vaccine against HPV-16 cancers.
authors.affiliation: Department of Medical Biotechnology, Faculty of Advanced Medical Technologies, Golestan University of Medical Sciences, Gorgan, Iran.
authors.forename: Armina Alagheband
authors.initials: AA
authors.lastname: Bahrami
authors.affiliation: Department of Microbiology, Golestan University of Medical Sciences, Gorgan, Iran; Shefa Neuroscience Research Center, Tehran, Iran. Electronic address: ghaemia@goums.ac.ir.
authors.forename: Amir
authors.initials: A
authors.lastname: Ghaemi
authors.affiliation: Department of Microbiology, Golestan University of Medical Sciences, Gorgan, Iran.
authors.forename: Alijan
authors.initials: A
authors.lastname: Tabarraei
authors.affiliation: Shefa Neuroscience Research Center, Tehran, Iran.
authors.forename: Azadeh
authors.initials: A
authors.lastname: Sajadian
authors.affiliation: Shefa Neuroscience Research Center, Tehran, Iran; Institut für Physiologie I, Westfälische Wilhelms-Universität Münster, Robert-Koch-Strasse Münster, Germany; Klinik und Poliklinik für Neurochirurgie, Westfälische Wilhelms-Universität Münster, Münster, Germany.
authors.forename: Ali
authors.initials: A
authors.lastname: Gorji
authors.affiliation: Department of Virology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
authors.forename: Hoorieh
authors.initials: H
authors.lastname: Soleimanjahi
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D001665:Binding Sites; D016207:Cytokines / Q000378:metabolism; D004195:Disease Models, Animal; D005260:Female; D052162:Human papillomavirus 16 / Q000235:genetics / Q000276:immunology*; D006801:Humans; D008810:Mice, Inbred C57BL; D050505:Mutant Proteins / Q000235:genetics / Q000276:immunology; D009369:Neoplasms / Q000517:prevention & control*; D050725:Papillomavirus E7 Proteins / Q000235:genetics / Q000276:immunology*; D030361:Papillomavirus Infections / Q000517:prevention & control*; D053918:Papillomavirus Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D011485:Protein Binding; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology
chemical_list: D016207:Cytokines; D050505:Mutant Proteins; D050725:Papillomavirus E7 Proteins; D053918:Papillomavirus Vaccines; D014614:Vaccines, Synthetic; C059731:oncogene protein E7, Human papillomavirus type 16
keywords: Cervical cancer; DNA vaccines; E7; Human papilloma virus; Mutant; pRb-binding motif