title: Gene therapy based on interleukin-12 loaded chitosan nanoparticles in a mouse model of fibrosarcoma.
abstract: OBJECTIVE
  Interleukin-12 (IL-12) as a cytokine has been proved to have a critical role in stimulating the immune system and has been used as immunotherapeutic agents in cancer gene therapy. Chitosan as a polymer, with high ability of binding to nucleic acids is a good candidate for gene delivery since it is biodegradable, biocompatible and non-allergenic polysaccharide. The objective of the present study was to investigate the effects of cells transfected with IL-12 loaded chitosan nanoparticles on the regression of fibrosarcoma tumor cells (WEHI-164) in vivo.
  
  
  METHODS
  WEHI-164 tumor cells were transfected with IL-12 loaded chitosan nanoparticles and then were injected subcutaneously to inoculate tumor in BALB/c mice. Tumor volumes were determined and subsequently extracted after mice sacrifice. The immunohistochemistry staining was performed for analysis of Ki-67 expression (a tumor proliferation marker) in tumor masses. The expression of IL-12 and IFN-γ were studied using real-time polymerase chain reaction and immunoblotting.
  
  
  RESULTS
  The group treated with IL-12 loaded chitosan nanoparticles indicated decreasing of tumor mass[r1] volume (P<0.001). The results of western blotting and real-time PCR showed that the IL-12 expression was increased in the group. Immunohistochemistry staining indicated that the Ki-67expression was reduced in the group treated with IL-12 loaded chitosan nanoparticles.
  
  
  CONCLUSIONS
  IL-12 gene therapy using chitosan nanoparticles has therapeutic effects on the regression of tumor masses in fibrosarcoma mouse model.
authors.affiliation: Immonuology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Saiedeh Razi
authors.initials: SR
authors.lastname: Soofiyani
authors.affiliation: Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran; Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Somayeh
authors.initials: S
authors.lastname: Hallaj-Nezhadi
authors.affiliation: Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran; Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Farzaneh
authors.initials: F
authors.lastname: Lotfipour
authors.affiliation: Immonuology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Akbar Mohammad
authors.initials: AM
authors.lastname: Hosseini
authors.affiliation: Immonuology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Behzad
authors.initials: B
authors.lastname: Baradaran
keywords: Chitosan; Gene therapy; IL-12; In vivo; Nanoparticle; Tumor