Fig. 2

Expression levels of tumor suppressor genes calcium channel regulatory subunit α2δ3 (CACNA2D3), retinoblastoma protein-interacting zinc finger gene 1 (RIZ1), and checkpoint with forkhead and ring finger domains (CHFR) in nasopharyngeal brushing and tissue samples. The relative expression levels of CACNA2D3 (a, d), CHFR (b, e), and RIZ1 (c, f) in nasopharyngeal brushing and tissue samples from healthy controls, nasopharyngitis patients, and NPC patients were measured by real-time quantitative polymerase chain reaction. Data were analyzed by the Mann–Whitney U test. SD standard deviation. *P < 0.05, **P < 0.01, ***P < 0.001