The second category of markers is associated with the degree of malignancy of the tumor and can be used to determine the grade and prognosis of bladder cancer, such as P16INK4a and CXCR4.30, 31 Although not included in the present study, the application of these biomarkers is expected to improve the efficiency of diagnosis, and can make a preliminary judgment on the classification and prognosis of tumors. The gene discussed is CXCR4; the disease is urinary bladder cancer.