HIF1A and infection: Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway analysis showed that OS-related DEGs were mainly enriched in pathways associated with cancer, lipid and atherosclerosis, hypoxia-inducible factor 1 (HIF-1) signalling pathway, cytokine-cytokine receptor interactions, PI3K-Akt signalling pathway, proteoglycan metabolism in cancer, infection of human cytomegalovirus, diabetic cardiomyopathy, and mitogen-activated protein kinase (MAPK) signalling pathway (Fig. 1B).