F2 and cancer: The membrane bound FGL2 has been shown to possess a serine protease activity, cleaving prothrombin to thrombin leading to fibrin deposition and thrombosis and was originally found to be implicated in the pathogenesis of fulminant hepatitis in humans (Levy et al, 2000) and has been used as a biomarker of severe liver diseases, including cancer (Foerster et al, 2010; Manns et al, 2017; Liu et al, 2021).