ACE2 and lung adenocarcinoma: As the expression of angiotensin-converting enzyme 2 (ACE2), the receptor of SARS-CoV-2, was aberrantly expressed in many tumors, in this study we investigated expression of ACE2 5, 6 in non-small cell lung cancer (NSCLC) including lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) and its association with prognosis with the aim of understanding the role of ACE2 expression in lung cancer survival.