Nobiletin induces growth inhibition and apoptosis in human nasopharyngeal carcinoma C666‐1 cells through regulating PARP‐2/SIRT1/AMPK signaling pathway

BACKGROUND/AIM: Nobiletin, a major polymethoxyflavones (PMFs) from citri reticulatae pericarpium (CRP), can inhibit several forms of cancer proliferation. However, the effects of nobiletin on nasopharyngeal carcinoma (NPC) C666‐1 cells remain largely unknown. MATERIALS AND METHODS: Cell counting kit 8 (CCK8) assay was used to measure cell vitality. Flow cytometry was performed to measure the apoptosis rate. Quantitative real‐time polymerase chain reaction (qRT‐PCR) and Western blot analysis were applied to determine the expression of mRNA and protein, respectively. RESULTS: We showed that the proliferation rate of C666‐1 cells was inhibited and the apoptosis rate was raised after treating with nobiletin. Moreover, nobiletin inhibited the expression of poly(ADP‐ribose)polymerase‐2 (PARP‐2), and the tumor suppression effect of nobiletin on C666‐1 is associated with PARP‐2‐dependent pathway. CONCLUSION: We demonstrated for the first time that nobiletin inhibited the growth of C666‐1 cells, which may be relative to its regulation on PARP‐2/SIRT1/AMPK signaling pathway. Our result implied that nobiletin may serve as a strategy to treat nasopharyngeal carcinoma.