In terms of KEGG pathways, a total of 19 pathways were identified including AGE−RAGE signaling pathway in diabetic complications, bladder cancer, amoebiasis, transcriptional misregulation in cancer, non−small cell lung cancer, microRNAs in cancer, rheumatoid arthritis, prostate cancer, malaria, proteoglycans in cancer, human T-cell leukemia virus 1 infection, alcoholic liver disease, melanoma, tyrosine metabolism, complement and coagulation cascades, IL-17 signaling pathway, relaxin signaling pathway and renin-angiotensin system (Figure 4D). The gene discussed is REN; the disease is lung cancer.