ACE2 and lung cancer: Renin-angiotensin system of both host and tumor cells plays a key role in tumor progression and angiogenesis in some types of cancers such as lung cancer.13,14 Shortly after the beginning of the COVID-19 pandemic, it was shown that angiotensin converting enzyme 2 (ACE2) was the cell surface binding site for the coronavirus SARS-CoV-2 entry and disease development.1 Recent studies have proposed that an imbalance in the action of ACE1- and ACE2-derived peptides, can enhance angiotensin II signaling, which is considered a primary driver of COVID-19 pathophysiology.15