Mechanisms of the gut-lung axis in regulating lung metastasis of colorectal cancer and advances in traditional Chinese medicine intervention

Figure 3 Formation of the lung pre-metastatic niche that is mediated by exosomes from the gut. Colorectal cancer cells which are infected with Fusobacterium nucleatum give out exosomes that hold hsa_circ_0004085, miR-1246, and other factors which promote metastasis. These exosomes move via blood circulation to the lung, where they are absorbed by fibroblasts and endothelial cells, thus inducing the expression of S100A8/A9 and fibronectin. Therefore, a microenvironment that permits the colonization of tumor cells is created. VCAM-1: Vascular cell adhesion molecule-1.