The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed 20 significantly enriched pathways (P < 0.05) in liver (Additional file 6: Figure S1A_left panel), some of which were associated with glucose and fat acid metabolism (e.g., adipocytokine signaling pathway), hormone regulation (e.g., estrogen signaling pathway), and cancer pathways (e.g., PPAR signaling pathway), suggesting that HS response may be a complex process comprising of neurohormonal regulation, energy metabolism, and immune response. The gene discussed is PPARA; the disease is cancer.