Combining Gene and Immunotherapy for Prostate Cancer

Prostate Cancer Prostatic Dis. 2008;11(2):187-93. doi: 10.1038/sj.pcan.4501008. Epub 2007 Aug 28.

Abstract

The nitroreductase (NR)/CB1954 enzyme prodrug system has given promising results in pre-clinical studies and is currently being assessed in phase I and II clinical trials in prostate cancer. Enhanced cell killing by apparent immune-mediated mechanisms has been shown in pancreatic and colorectal cancer models, by co-expressing murine granulocyte macrophage colony-stimulating factor (GM-CSF) with NR in a single replication deficient adenoviral vector. This consists of the CMV immediate early promotor driving expression of NR, with an internal ribosome entry site (IRES) and the gene for murine GM-CSF (mGM-CSF). To examine if similar enhancement of tumour cell killing could be produced in prostate cancer, the TRAMP model was chosen. Results illustrate that the combination of suicide gene therapy using NR and CB1954, with cytokine stimulation with mGM-CSF gives an improved response compared with either modality alone. The mechanism of this improved response is however likely to be non-immune based as it lacks a memory effect.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / genetics
  • Adenocarcinoma / immunology
  • Adenocarcinoma / therapy*
  • Adenoviridae / genetics
  • Animals
  • Antineoplastic Agents / pharmacokinetics
  • Antineoplastic Agents / therapeutic use*
  • Antineoplastic Agents / toxicity
  • Aziridines / pharmacokinetics
  • Aziridines / therapeutic use*
  • Aziridines / toxicity
  • Biotransformation
  • Combined Modality Therapy
  • Defective Viruses / genetics
  • Escherichia coli Proteins / genetics
  • Escherichia coli Proteins / metabolism*
  • Genes, Synthetic
  • Genes, Transgenic, Suicide*
  • Genetic Therapy* / methods
  • Genetic Vectors / therapeutic use*
  • Granulocyte-Macrophage Colony-Stimulating Factor / genetics
  • Granulocyte-Macrophage Colony-Stimulating Factor / therapeutic use*
  • Immunotherapy* / methods
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Neoplasm Transplantation
  • Nitroreductases / genetics
  • Nitroreductases / metabolism*
  • Prodrugs / pharmacokinetics
  • Prodrugs / therapeutic use*
  • Prostatic Neoplasms / genetics
  • Prostatic Neoplasms / immunology
  • Prostatic Neoplasms / therapy*
  • Recombinant Proteins
  • Specific Pathogen-Free Organisms

Substances

  • Antineoplastic Agents
  • Aziridines
  • Escherichia coli Proteins
  • Prodrugs
  • Recombinant Proteins
  • tretazicar
  • Granulocyte-Macrophage Colony-Stimulating Factor
  • NfsA protein, E coli
  • Nitroreductases