Caught in a Web: Emerging Roles of Neutrophil Extracellular Traps in Cancer

Neutrophil extracellular traps (NETs) are meshes of DNA decorated with granular proteins that are extruded from neutrophils during immune responses to pathogens. However, excessive NET formation is negatively associated with many diseases, including cancer. NETs contain, for example, proteases, danger-associated molecular patterns (DAMPs), and DNA. These components can act directly on the cancer cells but also affect the surrounding microenvironment, including altering the extracellular matrix and the immune response to tumors. Here, we discuss the emerging roles of NETs in cancer progression, from their ability to promote primary tumor growth and immune escape to their prometastatic effects. The potential clinical implication of targeting NETs as novel therapeutic strategies in cancer is also discussed.