For instance, cytosolic NPM1 binds and inhibits caspases 6 and 838 and the PTEN deubiquitinating enzyme HAUSP, resulting in PTEN cytoplasmic polyubiquitinilation and degradation.39 Thus a third important tumor suppressor is also deregulated by the presence of NPM1 in the cytosol. Here, NPM1 is linked to neoplasm.