Bacteria-based immunotherapy: A promising frontier in cancer treatment

Cancer remains a significant medical challenge, with uncontrollable cell growth leading to death. Bacteria-based cancer immunotherapy (BCiT) was first attempted in the 19th century and has shown promise in alternative treatments for cancer. Recent evidence suggests that BCiT can modulate immune responses via cellular and molecular pathways, with bacteria demonstrating an anticancer effect through toxins and cell membrane components. This study aims to investigate the progress of bacteria-based immunotherapy for cancer treatment, using data from previous studies. Bacterial-based immunotherapy harnesses immune cells to directly terminate tumor cells. through secondary analysis of previous research studies, comprehensive reviews of relevant literature were conducted. The PubMed, Science Direct and Frontiers databases were searched with the keywords “bacteria-based immunotherapy,” "bacteriotherapy,” and “cancer immunotherapy","bacteriotherapy,” and “cancer immunotherapy." A literature review was conducted, focusing on articles published no later than 5 years old. The safety and efficacy of BCiT are achieved through synthetic biology tools for genetic engineering. Combining bacterial vaccines with conventional therapies could enhance therapeutic benefits against cancer. However, the clinical manifestation of bacterial-based immunotherapy is limited due to potential infection and biosafety-associated toxicity and uncertain behavior in vivo. This review demonstrates the role of bacteria in the tumor microenvironment and provides a summary of strategies for immunotherapy based on their potential for cancer management. We will also propose advancements towards facilitating clinical translation for bacteria-based immunotherapy