PIK3CA and COVID-19: The results showed that cell proliferation, cell biological regulation, nucleic acid metabolism and protein transcription and translation were mainly involved in GO processes (Figure 5C), and CEP mainly played 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 (Figure 5D; Table 1).