A new method for treating colon and rectal cancer has been proposed based on both natural and genetically modified bacteriophages specific to the pathogenic bacterium Fusobacterium nucleatum .

Scientists from the American biotechnology company BiomX Inc. analyzed tumor tissue samples obtained from patients with colorectal cancer and found that 80% of them contained the pathogenic bacterium Fusobacterium nucleatum , in most cases the subspecies Fusobacterium nucleatum animalis . The scientists hypothesize that inflammation caused by F. nucleatum increases the risk of carcinogenesis.

The presence of certain bacteria as a significant risk factor for tumor development theoretically opens the possibility of using specific bacteriophages to prevent malignant neoplasms. Conversely, phages specific to F. nucleatum can be used to deliver various immunostimulatory or anticancer agents, or more precisely, the genes encoding them, to tumor tissue. For example, genes encoding granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-15 (IL-15), and the cytosine deaminase enzyme, which locally converts prodrugs into active substances, have been inserted into the bacteriophage genome.

In colorectal cancer, genetically modified bacteriophages can be used in conjunction with modern anti-tumor therapy—checkpoint inhibitors—because for checkpoint inhibitors to work, the tumor needs to be “warmed up”—activated—by immune processes within it.

* Ninio-Many L, Buchshtab N, Vainberg Slutskin I, Weiner I et al. Novel Analysis of Fusobacterium Nucleatum Subspecies in Human Colorectal Cancer and Engineering of Therapeutic Bacteriophage / Poster presentation at the European Society for Medical Oncology (ESMO) Immuno-Oncology Virtual Congress 2020