PIK3CD and COVID-19: CEP has a good binding force with AKT Serine/Threonine Kinase 1 (AKT1), phosphatidylinositol 3-kinase (PIK3) CA, PIK3CD and Angiotensin-converting enzyme 2 (ACE2), and plays a role in the treatment of COVID-19 by regulating PI3K-Akt signaling pathway, Relaxin signaling pathway, VEGF signaling pathway and HIF-1 signaling pathway.