Conventional to bacteria-based cancer therapy through bacterial components and drug delivery approaches: Pre-clinical, clinical, and future progression

Cancer is one of the current unwinnable battles, despite the abundance of treatments available. Traditional treatments like chemotherapy, radiation therapy, and surgery have been used for many years, but they are insufficient against advanced tumors. Small molecules, supramolecular complexes, modified immune cells, and plant-based molecules have all contributed to significant improvements in cancer therapy. However, certain undesirable activities and obstacles are on the horizon. To overcome such problems, research into bacterial strain-based cancer therapy has recently begun in both preclinical and clinical settings. In this context, many bacterial strains are used after genetic modification or as an innovative and smart delivery system. In this review, we have discussed several bacterial components with anti-cancerous properties, immunotherapeutic properties, and their products, such as endotoxins, peptides, etc., as well as genetically modified bacterial strains as therapeutic drug-delivery agents in cancer treatments. Herein, state-of-the-art advances, shortcomings of these therapies, and future advancements in bacteria-based therapies have also been discussed.