CD8A and urinary bladder cancer: Apart from the already mentioned positive feedback loop, the circNIPBL/miR-16-2-3p/Wnt5a/ZEB1 axis in bladder cancer [73], circMGA/HNRNPL complex as a pivotal tumor suppressor by recruiting CD8 + T cells in bladder cancer [74], and loop among circCDK13/miR-212-5p/449a/E2F5 in prostate carcinogenesis [75] were also shown to participate in tumor progression.