The results were consistent with previous reports, specifically that SIGLEC15 is upregulated in various tumors, including bladder urothelial carcinoma, cervical squamous cell carcinoma and endocervical adenocarcinoma, CHOL, colon adenocarcinoma, LUAD, KICH, KIRP, thyroid carcinoma, and uterine corpus endometrial carcinoma to varying degrees and can be used as a novel immune checkpoint for tumor immunotherapy (46). This evidence concerns the gene SIGLEC15 and bladder transitional cell carcinoma.