Activating Invasion and Metastasis

The prognosis of cancer patients is closely related to the invasiveness and subsequent metastasis in tissues distant from the primary tumor. This metastatic spread of the primary tumor accounts for more than 90% of mortality in patients with solid tumors. Invasiveness and metastasis are related to a complex of factors such as disruption of E-cadherins and tight junctions, signaling pathways involving urokinase type plasminogen activator, phosphatidylinositol 3-kinase/v-act murine thymoma viral oncogene, focal adhesion kinase, β-catenin/zinc finger E-box binding homeobox 1 (ZEB-1), and transforming growth factor beta, together with activator protein-1 (AP-1) and increased activity of matrix metalloproteinases. A process of epithelial–mesenchymal transition also plays an important role in invasiveness (Jiang et al. 2015).