TMPRSS2 and COVID-19: Then, we focused on the expression characteristics and functions of SARS-CoV-2 Receptors including ACE2, TMPRSS2, and AAK1 in LUAD as well as their relationship with the level of immune infiltration and explored the potential therapeutic targets and drugs for ACE2, TMPRSS2, and AAK1, then further indicated the anti-inflammatory effect of SARS-CoV-2 Receptors inhibitor bexarotene, providing promising ideas for the treatment of COVID-19.