Cystatin F (CST7) expression is predominantly found in the bone marrow and spleen, suggesting a putative role in immune regulation.51 Although CST7 expression has been reported in human cancer cells derived from malignant tumors,16 it has also been associated with patient outcomes.60 In this study, our analysis revealed that the CST7 gene was not expressed in bladder cancer cell lines, and its expression in bladder tissues was lower than in benign tissues. Here, CST7 is linked to urinary bladder cancer.