DNase I is a secreted
enzyme whose function has been presumed to control "waste management" in the human system, by degrading
DNA that leaks from dead and dying cells. Emerging studies have instead yielded evidence that
DNase I plays a central role in newly defined dynamics of immune and
autoimmune diseases, as well as
cancer and vascular disorders, including
thrombosis.
Cancer cells have been reported to be associated with distinctive extracellular structures that facilitate aggregation and implantation. The fact that
DNA is a component of such structures and that it plays a role in
cancer development is illustrated by direct evidence:
DNase I added to
tumor cells eliminates the structures and inhibits tumorigenicity of some
cancer cell lines.
DNase I injected into experimental animals, moreover, results in significant inhibition of
metastasis. Despite independent observations of such phenomena in diverse
cancers for over 50 years, the potential for using
DNase I as a clinical tool to prevent or treat
cancer remains unexplored. The discovery of neutrophil extracellular traps has yielded a conceptual framework for interpreting how extracellular
DNA may function in
cancer development and why it may prove to be an important clinical target in stopping
cancer outside the cell.