SOAT1 and nicotine dependence: Enrichment analysis of 301 up-regulated differential genes showed that the KEGG pathways were significantly enriched in cytokine-cytokine receptor interaction, jak-STAT signaling pathway, nicotine addiction, chemokine signaling pathway, hematopoietic cell lineage, steroid hormone biosynthesis, butanoate metabolism, and neuroactive ligand-receptor interaction (Figure 2B).