APEX1 and amyotrophic lateral sclerosis: KEGG enrichment analysis showed that after silencing of APEX1, the top 20 signaling pathways that DEGs are involved in were related to amyotrophic lateral sclerosis (ALS); the synaptic vesicle cycle; proximal tubule bicarbonate reclamation; glycine, serine and threonine metabolism; neomycin, kanamycin and gentamicin biosynthesis; carbohydrate digestion and absorption; transcriptional misregulation in cancers; the tumor necrosis factor (TNF) signaling pathway; endocrine and other factor-regulated calcium reabsorption and arginine and proline metabolism (Figure 5C).