TMPRSS2 and gastric carcinoma: First, we disrupted ACE2, TMPRSS2, and LGMN in the gastric carcinoma cell line NCC-Stk-K140, which expresses moderate levels of ACE2, low levels of TMPRSS2, and high levels of LGMN (Fig 3B) and serves as a potential model system for SARS-CoV-2 infection of the gut [40,41].