Murine models of cancer cytokine gene therapy using interleukin-12

Ann N Y Acad Sci. 1996 Oct 31;795:275-83. doi: 10.1111/j.1749-6632.1996.tb52677.x.


Cytokine gene therapy, in particular IL-12 gene therapy, is one of the more novel and promising approaches in cancer therapy based on significant preclinical data derived mainly from murine tumor models. IL-12 is a heterodimeric cytokine that requires the simultaneous expression of both the p35 and p40 chains from the same cell for production of biologically active IL-12. A variety of biological functions have been attributed to IL-12 including the induction of IFN-gamma production and the promotion of predominantly Th1-type immune responses to antigens. Our previous studies using systemic administration of recombinant murine IL-12 have demonstrated profound antitumor efficacy against all tumors tested with the concomitant long-lived specific antitumor immunity in some cases. To determine whether the local secretion of IL-12 achieved by gene transduction has significant antitumor effects, fibroblast cell lines or murine tumor cell lines were transduced with expression plasmids or the retroviral vector TFG-mIL-12-Neo and inoculated intradermally (i.d.). Our first study using IL-12-transfected NIH3T3 cells admixed with the murine melanoma, BL-6, showed that local IL-12 expression suppresses tumor growth and promotes the acquisition of specific antitumor immunity. Subsequent studies showed that IL-12 gene therapy is also effective in treating established day 3 tumors. CD4+ and CD8+ T cells, as well as NK cells, appear to play important roles in the observed antitumor effects resulting from IL-12 paracrine secretion. Administration of neutralizing antibody specific for IFN-gamma also abrogated some of the IL-12-associated antitumor effects. Finally, this IL-12 gene therapy strategy to elicit an antitumor immune response was more effective when used in combination with the transduction of tumor cells with B7.1. Based on these promising results, a clinical protocol for the treating patients with cancer using genetically engineered fibroblasts to express IL-12 has been initiated at our institution.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Antineoplastic Agents / administration & dosage*
  • B7-1 Antigen / administration & dosage
  • Genetic Therapy
  • Genetic Vectors
  • Immunity, Cellular
  • Interferon-gamma / physiology
  • Interleukin-12 / administration & dosage*
  • Killer Cells, Natural / immunology
  • Mice
  • Neoplasms, Experimental / therapy*
  • Transduction, Genetic
  • Transfection


  • Antineoplastic Agents
  • B7-1 Antigen
  • Interleukin-12
  • Interferon-gamma