RESUMEN
Millions of people die from cancer every year.Because of its extremely complex etiology, humans still cannot he completely cured.In the war against cancer, bacteria effectively inhibit the growth of tumor cells, so it shows the potential as a tumor therapy.Compared with traditional chemotherapy methods, tumor-targeting bacteria have the ability to specifically colonize the tumor microenvironment, which greatly avoids the damage to normal tissues in cancer treatment, and improves the targeting and safety of treatment.At the same time, the development of synthetic biology has expanded the toolbox to optimize the lethality of bacteria to tumor by expressing protein effectors.Therefore, the gene circuit in human probiotic E.coli Nissle 1917 (EcN) is modified to make it " intelligent" , so as to optimize the method of using bacteria to treat cancer.This paper mainly reviews the history of using bacteria to treat cancer, highlights the methods of engineering EcN by synthetic biology, discusses the safety, efficiency and controllability of genetically modified live bacteria, and looks forward to the future development of bacteria in the treatment of cancer under the guidance of synthetic biology.