Except in human clinical trials, preclinical tests showed the potential of Salmonella bacteria for tumor therapy. There are still various challenges to tackle before salmonella bacteria may be employed to treat human cancer. Due to its pathogenic nature, attenuation is essential to minimize the host's harmful effects of bacterial infection. Loss of anticancer efficacy from bacterial virulence attenuation can be compensated by giving therapeutic payloads to microorganisms. Bacteria can also be linked to micro-or nanomaterials with diverse properties, such as drug-loaded, photocatalytic and/or magnetic-sensing nanoparticles, using the net negative charge of the bacteria. Combining bacteria-mediated cancer treatment with other medicines that have been clinically shown to be helpful but have limits may provide surprising therapeutic results. Recently, this strategy has received attention and is underway. The use of live germs for cancer treatment has not yet been approved for human clinical trials. The non-invasive oral form of administration benefits from safety, making it more suitable for clinical cancer patients.Infection of live germs through systemic means, on the other hand, involves toxicity risk. Although Salmonella bacteria can be genetically manipulated with high tumor targeting, harm to normal tissues can not be excluded when medications with nonspecific toxicity are administered. It is preferred if the action of selected drugs may be restricted to the tumor site rather than healthy tissues, thereby boosting cancer therapy safety. In recent years, many regulatory mechanisms have been developed to manage pharmaceutical distribution through live bacterial vectors. Engineered salmonella can accumulate 1000 times greater than normal tissue density in the tumor. The QS-regulated mechanism, which initiates gene expression when bacterial density exceeds a particular threshold level, also promises Salmonella bacteria for targeted medication delivery. Nanovesicle structures of Salmonella bacteria can also be used as biocompatible nanocarriers to deliver functional medicinal chemicals in cancer therapy. Surface-modified nanovesicles preferably attach to tumor cells and are swallowed by receptor-mediated endocytosis before being destroyed to release packed drugs. The xenograft methodology, which comprises the implantation of cultivated tumor cell lines into immunodeficient mice, has often been used in preclinical research revealing favorable results about the anticancer effects of genetically engineered salmonella.
The Evolution of Retinal Gene Therapy: From Clinical Trials to Clinical Practice
