We compared the transcriptome differences between malignant epithelium of patients with CG and malignant epithelial cells of cancer patients and found that most genes were downregulated in CG and only a few genes were upregulated in cystitis, such as OLFM4, PIGR, FABP4, TCIM, MUC4, DENND2C, ARL14, and CXCL8 (Figures 2B, C). The gene discussed is PIGR; the disease is cancer.