Attenuated Bacteria as Immunotherapeutic Tools for Cancer Treatment
- 1Medical Microbiology and Immunology, United Arab Emirates University, United Arab Emirates
- 2Biochemistry, United Arab Emirates University, United Arab Emirates
- 3Rheumatology and clinical immunology, Universität zu Lübeck, Germany
The use of attenuated bacteria as cancer therapeutic tools has garnered increasing scientific interest over the past 10 years. This is largely due to the development of bacterial strains that maintain good anti-tumor efficacy but with reduced potential to cause toxicities to the host. Because of its ability to replicate in viable as well as necrotic tissue, cancer therapy using attenuated strains of facultative anaerobic bacteria, such as Salmonella, has several advantages over standard treatment modalities, including chemotherapy and radiotherapy. Despite some findings suggesting that it may operate through a direct cytotoxic effect against cancer cells, there is accumulating evidence demonstrating that bacterial therapy acts by modulating cells of the immune system to counter the growth of the tumor. Herein, we review the experimental evidence underlying the success of bacterial immunotherapy against cancer and highlight the cellular and molecular alterations in the peripheral immune system and within the tumor microenvironment that have been reported following different forms of bacterial therapy. Our improved understanding of these mechanisms should greatly aid in the translational application of bacterial therapy to cancer patients.
Keywords: bacterial therapy, Attenuated Salmonella, cancer immunotherapy, Tumor Microenvironment, TILs, MDSCs
Received: 22 Mar 2018;
Accepted: 16 Apr 2018.
Edited by:Masoud H. Manjili, Massey Cancer Center, Virginia Commonwealth University, United States
Reviewed by:Caitlin S. Parello, Biomodels, LLC
Michael Kogut, Agricultural Research Service (USDA), United States
Copyright: © 2018 Kaimala, Al Sbiei, Cabral-Marques, Fernandez-Cabezudo and Al-Ramadi. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Prof. Basel K. Al-Ramadi, United Arab Emirates University, Medical Microbiology and Immunology, Al-Ain, United Arab Emirates, email@example.com