Related TTSPs, like transmembrane protease serine 2 (TMPRSS2) or human airway trypsin-like protease (HAT), and differentially expressed in squamous cell carcinoma-1 (DESC1) protein can also activate surface glycoproteins of different viruses, e.g. certain influenza viruses.14 Here, TMPRSS11D is linked to squamous cell carcinoma.