Bacteria-mediated Cancer Therapy Research Articles

Targeted cancer immunotherapy with genetically engineered oncolytic Salmonella typhimurium.

Conventional chemotherapies have some limitations, including the lack of selectivity, high toxicity to normal tissues, multidrug resistance, and tumor relapse. Recently, great progress was made in immunotherapies for anticancer research, with bacteria-mediated cancer therapy one of the most promising approaches among them. Attenuated Salmonella have very specific targeting to various solid cancers, making them ideal vectors for the delivery and expression of immunostimulators. They have native bacterial immunogenicity and induce strong anticancer immunity in vivo. In this review, the recent advances in Salmonella-mediated cancer immunotherapies and the related mechanisms of Salmonella-based cancer therapies are summarized.

Salmonella-Mediated Cancer Therapy: Roles and Potential.

The use of bacteria for cancer therapy, which was proposed many years ago, was not recognized as a potential therapeutic strategy until recently. Technological advances and updated knowledge have enabled the genetic engineering of bacteria for their safe and effective application in the treatment of cancer. The efficacy of radiotherapy depends mainly on tissue oxygen levels, and low oxygen concentrations in necrotic and hypoxic regions are a common cause of treatment failure. In addition, the distribution of a drug is important for the therapeutic effect of chemotherapy, and the poor vasculature in tumors impairs drug delivery, limiting the efficacy of a drug, especially in necrotic and hypoxic regions. Bacteria-mediated cancer therapy (BMCT) relies on facultative anaerobes that can survive in well or poorly oxygenated regions, and it therefore improves the therapeutic efficacy drug distribution throughout the tumor mass. Since the mid-1990s, the number of published bacterial therapy papers has increased rapidly, with a doubling time of 2.5years in which the use of Salmonella increased significantly. BMCT is being reevaluated to overcome some of the drawbacks of conventional therapies. This review focuses on Salmonella-mediated cancer therapy as the most widely used type of BMCT.2.

Noninvasive In Vivo Imaging to Follow Bacteria Engaged in Cancer Therapy.

Non-invasive in vivo imaging represents a powerful tool to monitor cellular and molecular processes in the living animal. In the special case of bacteria-mediated cancer therapy using bioluminescent bacteria, it opens up the possibility to follow the course of the microorganisms into the tumor via the circulation. The mechanism by which bacteria elicit their anti-tumor potential is not completely understood. However, this knowledge is crucial to improve bacteria as an anti-cancer tool that can be introduced into the clinic. For the study of these aspects, in vivo imaging can be considered a key technology.