Current Understanding of Microbiomes in Cancer Metastasis

Simple Summary Microbiomes, inhabiting multiple parts of the human body, are considered to be associated with the progress, treatment, and prognosis of cancer. Metastasis is a main cause for high mortality of cancer, and there is increasing attention to the issue of the relationship between microbiomes and cancer metastasis. This review summarizes the recent advances in this field. Cancer has been the first killer that threatens people's lives and health. Despite recent improvements in cancer treatment, metastasis continues to be the main reason for death from cancer. The functions of microbiome in cancer metastasis have been studied recently, and it is proved that microbiome can influence tumor metastasis, as well as positive or negative responses to therapy. Here, we summarize the mechanisms of microorganisms affecting cancer metastasis, which include epithelial-mesenchymal transition (EMT), immunity, fluid shear stress (FSS), and matrix metalloproteinases (MMPs). This review will not only give a further understanding of relationship between microbiome and cancer metastasis, but also provide a new perspective for the microbiome's application in cancer metastasis prevention, early detection, and treatment.