In bladder cancer, circPTK2 binds with PABPC1, enhancing its ability to stabilize SETDB1 mRNA, promoting SETDB1-mediated EMT, significantly increasing in vitro migration and invasion capabilities, as well as gemcitabine resistance.592 CircIPO7 binds with the cytoplasmic Y-box binding protein-1 (YBX1), activating AKT phosphorylation to promote YBX1 nuclear translocation, increasing nasopharyngeal carcinoma’s resistance to cisplatin treatment.593 CircRNAs also affect the polarization of tumor-associated macrophages, thereby regulating chemoresistance. The gene discussed is YBX1; the disease is nasopharyngeal carcinoma.