Key cluster genes were upregulated for proteoglycans in cancer, bladder cancer, PI3K-Akt signaling pathway, AGE-RAGE signaling pathway in diabetic complications, HIF-1 signaling pathway, Kaposi sarcoma-associated herpesvirus infection, endocrine resistance, small cell lung cancer, pancreatic cancer, and human cytomegalovirus infection (Figures 6C,D). The gene discussed is HIF1A; the disease is cytomegalovirus infection.