title: High-yield expression, purification and characterization of tumor-targeted IFN-alpha2a.
abstract: BACKGROUND
  IFN-alpha has been shown to be effective against hematologic malignancies. However, it is ineffective against most solid tumors and has not been satisfactory because of its toxicity.
  
  
  METHODS
  The NGR (Asn-Gly-Arg) peptide is a tumor-homing peptide. In order to increase the anti-tumor activity of IFN-alpha2a and lower the dose, we coupled a cyclic NGR peptide with the C terminus of IFN-alpha2a (named IFN-alpha2a-NGR).
  
  
  RESULTS
  The fusion protein was expressed in E. coli and purified by ion-exchange chromatography. The purity of IFN-alpha2a-NGR was >98% and the final purification yield of IFN-alpha2a-NGR was approximately 18 mg/L. The anti-tumor efficacy and the binding ability of IFN-alpha2a-NGR with tumor vasculature were investigated in vitro and in vivo.
  
  
  CONCLUSIONS
  Our study has demonstrated that the anti-tumor efficacy of IFN-alpha2a-NGR is significantly increased in comparison with IFN-alpha2a, and IFN-alpha2a-NGR could selectively target tumor vessels. These data indicate that the tumor-homing peptide (NGR) can enhance the therapeutic efficacy of IFN-alpha2a against tumors.
authors.affiliation: Biotechnology Center of The Fourth Military Medical University, Xi'an, People's Republic of China.
authors.forename: J
authors.initials: J
authors.lastname: Meng
authors.forename: Z
authors.initials: Z
authors.lastname: Yan
authors.forename: J
authors.initials: J
authors.lastname: Wu
authors.forename: L
authors.initials: L
authors.lastname: Li
authors.forename: X
authors.initials: X
authors.lastname: Xue
authors.forename: M
authors.initials: M
authors.lastname: Li
authors.forename: W
authors.initials: W
authors.lastname: Li
authors.forename: Q
authors.initials: Q
authors.lastname: Hao
authors.forename: Y
authors.initials: Y
authors.lastname: Wan
authors.forename: X
authors.initials: X
authors.lastname: Qin
authors.forename: C
authors.initials: C
authors.lastname: Zhang
authors.forename: Y
authors.initials: Y
authors.lastname: You
authors.forename: W
authors.initials: W
authors.lastname: Han
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use; D002460:Cell Line; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D004847:Epithelial Cells / Q000166:cytology / Q000187:drug effects / Q000821:virology; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D006801:Humans; D016898:Interferon-alpha / Q000235:genetics*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D018613:Microscopy, Confocal; D009369:Neoplasms / Q000188:drug therapy* / Q000473:pathology; D009842:Oligopeptides / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000302:isolation & purification* / Q000494:pharmacology* / Q000627:therapeutic use; D023041:Xenograft Model Antitumor Assays / Q000379:methods
chemical_list: D000970:Antineoplastic Agents; D016898:Interferon-alpha; D009842:Oligopeptides; D011993:Recombinant Fusion Proteins; C047981:arginyl-glycyl-aspartic acid