Microbiology and Lung Cancer: A Comprehensive Review

There are hundreds of billions of bacterial flora distributed in the human skin, oral cavity, nasal cavity, stomach, small intestine, large intestine, urinary tract and vagina. There are currently more than 1,000 known human microbiota species. The microbiome lives symbiotically with our bodies and is a diverse community that includes bacteria, fungi, and viruses. It plays an important role in maintaining the body's internal balance, adjusting the immune system,and influencing genetic factors. Lung cancer ranks first among new malignant tumors and is also the leading cause of death from malignant tumors. Like most cancers, lung cancer is caused by multiple factors and has a complex pathogenesis, which may include susceptible hosts,  environmental factors, chronic disease burden, habits such as smoking and drinking,and other unidentified causes. In recent years, with the development of detection technology and the in-depth understanding of the tumor microenvironment, more and more evidence has confirmed the existence of bacteria within tumors, which has also  triggered further in-depth research in this field.Preliminary epidemiological studies have suggested a link between microbes and cancer. This review introduces the sources of microorganisms and their locations, outlines the relationship between lung, oral, and intestinal microbiota and lung cancer and biomolecular mechanisms, and summarizes methods to treat and prevent lung cancer by utilizing these characteristicmechanisms.