Proteomic screening of anaerobically regulated promoters from Salmonella and its antitumor applications

Mol Cell Proteomics. 2011 Jun;10(6):M111.009399. doi: 10.1074/mcp.M111.009399. Epub 2011 Apr 7.

Abstract

Solid tumors often contain hypoxic and necrotic areas that can be targeted by attenuated Salmonella typhimurium VNP20009 (VNP). We sought to develop a hypoxia- inducible promoter system based on the tumor-specific delivered strain VNP to confine expression of therapeutic gene specifically or selectively within the tumor microenvironment. A hypoxia-inducible promoter - adhE promoter was screened from the hypoxia-regulated endogenous proteins of Salmonella through two-dimensional gel electrophoresis and matrix-assisted laser desorption ionization-time-of-flight/time-of-flight MS-based proteomics approaches. The efficiency and specificity of the selected adhE promoter were validated first in both bacteria and animal tumor models. The adhE promoter could specifically drive GFP gene expression under hypoxia, but not under normoxia. Furthermore, luciferase reporter expression controlled by the system was also confined to the tumors. Finally, we investigated the anticancer efficacy of VNP delivering human endostatin controlled by our adhE promoter system in both murine melanoma and Lewis lung carcinoma models. Our results demonstrated that by the dual effects of tumoricidal and anti-angiogenic activities, the recombinant Salmonella strain could generate enhanced antitumor effects compared with those of unarmed VNP treatment or untreated control. The recombinant VNP could retard tumor growth significantly and extend survival of tumor-bearing mice by inducing more apoptosis and more severe necrosis as well as inhibiting blood vessel density within tumors. Therefore, VNP carrying the endostatin gene under our tumor-targeted expression system holds promise for the treatment of solid tumors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alcohol Dehydrogenase / genetics
  • Alcohol Dehydrogenase / metabolism
  • Anaerobiosis
  • Angiogenesis Inhibitors / metabolism*
  • Animals
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Base Sequence
  • Biological Therapy / methods*
  • Carcinoma, Lewis Lung / pathology
  • Carcinoma, Lewis Lung / therapy
  • Cell Death
  • Cell Hypoxia
  • Cell Line, Tumor
  • Chick Embryo
  • Chorioallantoic Membrane / blood supply
  • Endostatins / genetics
  • Endostatins / metabolism*
  • Female
  • Kaplan-Meier Estimate
  • Melanoma, Experimental / pathology
  • Melanoma, Experimental / therapy
  • Mice
  • Mice, Inbred C57BL
  • Neoplasm Transplantation
  • Organisms, Genetically Modified
  • Promoter Regions, Genetic*
  • Proteome / genetics*
  • Proteome / metabolism
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Salmonella typhimurium / genetics
  • Salmonella typhimurium / metabolism*
  • Tumor Burden
  • Up-Regulation

Substances

  • Angiogenesis Inhibitors
  • Bacterial Proteins
  • Endostatins
  • Proteome
  • Recombinant Fusion Proteins
  • Alcohol Dehydrogenase