REN and systemic lupus erythematosus: Among them, cell cycle, DNA replication, retinol metabolism, spliceosome, and systemic lupus erythematosus were the top 5 KEGG pathways enriched in the high-risk group according to normalized enrichment score (NES), while calcium signaling pathway, hematopoietic cell lineage, neuroactive ligand-receptor interaction primary immunodeficiency and renin-angiotensin system were the most relevant pathways in low-risk group (Figures 5A,B).