FURIN and diabetes mellitus: The increased expression of angiotensin-converting enzyme-2 (ACE2), a SARS-CoV-2 virus receptor, and a higher amount of intracellular furin in people with DM made it easier for the SARS-CoV-2 virus to enter cells and replicate, causing excessive inflammatory process, thereby increasing the morbidity and mortality of COVID-19 in people with type 2 DM [6–12].