Synthetic engineered bacteria for cancer therapy

ABSTRACTIntroduction Cancer mortality worldwide highlights the urgency for advanced therapeutic methods to fill the gaps in conventional cancer therapies. Bacteriotherapy is showing great potential in tumor regression due to the motility and colonization tendencies of bacteria. However, the complicated in vivo environment and tumor pathogenesis hamper the therapeutic outcomes. Synthetic engineering methods endow bacteria with flexible abilities both at the extracellular and intracellular levels to meet treatment requirements. In this review, we introduce synthetic engineering methods for bacterial modifications. We highlight the recent progress in engineered bacteria and explore how these synthetic methods endow bacteria with superior abilities in cancer therapy. The current clinical translations are further discussed. Overall, this review may shed light on the advancement of engineered bacteria for cancer therapy.Areas covered Recent progress in synthetic methods for bacterial engineering and specific examples of their applications in cancer therapy are discussed in this review.Expert opinion Bacteriotherapy bridges the gaps of conventional cancer therapies through the natural motility and colonization tendency of bacteria, as well as their synthetic engineering. Nevertheless, to fulfill the bacteriotherapy potential and move into clinical trials, more research focusing on its safety concerns should be conducted.KEYWORDS: Bacteriasynthetic engineering methodsdeliverycancer therapyBacteriotherapy Article highlights Bacteriotherapy is a novel and effective approach to cancer treatment.Due to their motility and colonization tendencies, bacteria can be capitalized upon as a vehicle to carry various anticancer toxic payloads and perform discrete functions in disease processes.Synthetic engineering methods have largely fulfilled the bacteriotherapy efficacy requirement by endowing bacteria with additional functions both at the extracellular and intracellular levels.Various bacteria strains are being evaluated in clinical trials of bacteriotherapy.Resolving safety concerns will greatly maximize the use of bacteriotherapy alone and in combination with other cell therapy treatments.Declaration of interestThe authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.Reviewer disclosuresPeer reviewers on this manuscript have no relevant financial or other relationships to disclose.Correction StatementThis article has been republished with minor changes. These changes do not impact the academic content of the article.Additional informationFundingThis paper was supported by the National Natural Science Foundation of China (No. 32171372).