Related Experiment Video

Updated: Jun 13, 2026

Measuring Growth and Gene Expression Dynamics of Tumor-Targeted S. Typhimurium Bacteria
08:11

Measuring Growth and Gene Expression Dynamics of Tumor-Targeted S. Typhimurium Bacteria

Published on: July 6, 2013

Role of nitric oxide in Salmonella typhimurium-mediated cancer cell killing

Yoram Barak1, Frank Schreiber, Steve H Thorne

  • 1Department of Microbiology and Immunology, Sherman Fairchild Science Building, Stanford University School of Medicine, 299 Campus Drive, Stanford, CA 94305, USA.

BMC Cancer
|April 20, 2010
PubMed
Abstract

Insights

Salmonella typhimurium bacteria can target and kill cancer cells. Enhanced nitric oxide (NO) generation by these bacteria significantly improves their anti-cancer efficacy, offering a promising therapeutic strategy.

Area of Science:

  • Microbiology
  • Cancer Biology
  • Immunotherapy

Background:

  • Bacterial tumor targeting is a key anti-cancer strategy.
  • Salmonella typhimurium strain SL7838 demonstrates tumor-targeting and cancer-killing abilities.
  • The role of nitric oxide (NO) in bacterial-mediated cancer cell lethality requires further investigation.

Purpose of the Study:

  • To investigate the role of nitric oxide (NO) generation in the anti-cancer activity of Salmonella typhimurium.
  • To compare the efficacy of different Salmonella strains with varying NO-producing capabilities in cancer therapy.

Main Methods:

  • In vitro and in vivo studies were conducted to elucidate the mechanism of Salmonella typhimurium tumor therapy.
  • Nitric oxide (NO) levels were measured using chemical assays and biosensors.
  • Cancer cell cytotoxicity was assessed using MTS assays, and tumor burden was monitored via molecular imaging.

Main Results:

  • Salmonella typhimurium strain SL7838 generated nitric oxide (NO) within cancer cells and tumors.
  • A modified strain, SL7842, with enhanced NO production (due to hmp and norV gene deletion), exhibited superior in vitro cancer cell killing and was approximately 100% more effective in treating implanted 4T1 mouse tumors compared to SL7838.
  • The enhanced anti-cancer effect of SL7842 was dependent on nitrate availability.

Conclusions:

  • The capacity for nitric oxide (NO) generation is crucial for the effectiveness of Salmonella strains in killing cancer cells.
  • Engineering Salmonella for enhanced NO production represents a promising strategy for improving bacterial cancer therapy.

More Related Videos

High-throughput Assay to Phenotype Salmonella enterica Typhimurium Association, Invasion, and Replication in Macrophages11:10

High-throughput Assay to Phenotype Salmonella enterica Typhimurium Association, Invasion, and Replication in Macrophages

Published on: August 11, 2014

A Protocol to Infect Caenorhabditis elegans with Salmonella typhimurium06:50

A Protocol to Infect Caenorhabditis elegans with Salmonella typhimurium

Published on: June 26, 2014

Related Concept Videos

Nitric Oxide Signaling Pathway01:28

Nitric Oxide Signaling Pathway

Nitric oxide (NO), an inorganic gas, acts as a potent second messenger in most animal and plant tissues. NO diffuses out of the cells that produce it and enters the neighboring cells to generate a downstream response. NO synthase (NOS) catalyzes NO production by the deamination of the amino acid arginine. There are three isoforms of NOS. Endothelial cells have endothelial NOS (eNOS), nerve and muscle cells have neuronal NOS (nNOS), and macrophages produce inducible NOS (iNOS) upon exposure to...
2° Amines to N-Nitrosamines: Reaction with NaNO201:20

2° Amines to N-Nitrosamines: Reaction with NaNO2

Secondary amines react with nitrous acid to form N-nitrosamines, as depicted in Figure 1. Nitrous acid, a weak and unstable acid, is formed in situ from an aqueous solution of sodium nitrite and strong acids, such as hydrochloric acid or sulfuric acid, in cold conditions. In the presence of an acid, the nitrous acid gets protonated. The subsequent loss of water results in the formation of the electrophile known as nitrosonium ion.
Gene Regulation in Microbial Communities: Quorum Sensing01:28

Gene Regulation in Microbial Communities: Quorum Sensing

Quorum sensing is a mechanism of bacterial communication that enables coordinated gene expression in response to changes in population density. This facilitates collective behaviors that enhance survival, resource acquisition, and ecological adaptation. This process relies on small signaling molecules called autoinducers that accumulate as bacterial populations grow. When a critical threshold concentration of autoinducers is reached, bacterial cells collectively modify gene expression,...
Regulation of Bacterial Virulence01:28

Regulation of Bacterial Virulence

Pathogenic bacteria employ a range of regulatory mechanisms to modulate the expression of virulence genes in response to environmental and host-derived signals. These mechanisms ensure that virulence factors are expressed only under favorable conditions, thereby optimizing infection and survival strategies.Mechanisms of Virulence RegulationKey regulatory strategies include:Two-Component Systems: These consist of a membrane-bound sensor kinase and a cytoplasmic response regulator. Environmental...