PPARA and breast cancer: Subsequently, to further explore the potential biological differences and pathways occurred in age-related breast cancer, KEGG analysis by employing DEGs showed that the DEGs were enriched in complement and coagulation cascades, neuroactive ligand-receptor interaction, cholesterol metabolism, PPAR signaling pathway, cortisol synthesis and secretion, systemic lupus erythematosus and so on (Figure 7C).