Tumor-targeted Salmonella. Highly selective delivery vectors

Area of Science:

• Oncology
• Microbiology
• Genetic Engineering

Background:

• Solid tumors present a significant challenge in cancer treatment.
• Developing targeted therapies with reduced systemic toxicity is crucial.
• Genetically modified bacteria offer a potential platform for cancer treatment.

Purpose of the Study:

• To evaluate the efficacy and safety of genetically engineered Salmonella for targeting solid tumors.
• To assess the bacteria's tumor specificity, replication capabilities, and antitumor effects.
• To investigate the potential of these bacteria as a drug delivery system for cancer therapy.

Main Methods:

• Systemic administration of genetically engineered Salmonella in preclinical tumor models.
• Assessment of bacterial tumor targeting and replication specificity.
• Evaluation of innate antitumor activity and potential for activating chemotherapeutic agents.
• Analysis of safety profiles, including septic shock potential and antibiotic susceptibility.

Main Results:

• Engineered Salmonella demonstrated high specificity (>1,000-fold) for tumors over other tissues.
• Auxotrophic mutations and altered lipids enhanced safety while retaining antitumor properties.
• Significant delay in tumor growth was observed, extending survival in mice up to twofold.
• Bacteria showed innate antitumor activity against primary and metastatic tumors and could deliver therapeutic proteins.

Conclusions:

• Genetically engineered Salmonella represent a promising, safe, and effective strategy for targeting and treating solid tumors.
• These bacteria possess inherent antitumor capabilities and can be utilized for targeted drug delivery.
• The ability to control the bacterial vector with antibiotics provides an additional safety mechanism.