TY - JOUR AB - Quercitrin, glycosylated form of flavonoid compounds, is widely distributed in nature. Extensive studies have demonstrated that quercitrin exhibits strong antioxidant and anti-carcinogenic activities. However, the molecular mechanism is poorly understood. The present study examines the effects of quercitrin on tumor promotion in mouse JB6 cells, a validated model for screening cancer chemopreventive agents and elucidating the molecular mechanisms. Quercitrin blocked TPA-induced neoplastic transformation in JB6 P+ cells. Pretreatment of JB6 cells with quercitrin down-regulated transactivation of AP-1 and NF-κB induced by UVB or TPA. In the skin of AP-1-luciferase transgenic mice, topical treatment of the mouse with quercitrin markedly blocked the TPA-induced AP-1 transactivation. Further studies indicated that these inhibitory actions appear to be mediated through the inhibition of MAPKs phosphorylation, including ERKs, p38 kinase, and JNKs. In addition, quercitrin stimulated the activation of NF-E2-related factor (Nrf2) and GST ARE-luciferase activity. Comet assays showed that quercitrin could block DNA damage induced by UVB. To our knowledge, these results provide the first evidence that quercitrin contributes to the inhibition of neoplastic transformation by blocking activation of the MAPK pathway and stimulation of cellular protection signaling. Moreover, to our knowledge, these findings provide the first molecular basis for the anti-carcinogenic action of quercitrin. AD - Pathology and Physiology Research Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV 26505, USA. mid5@cdc.gov null AU - Ding,Min AU - Zhao,Jinshun AU - Bowman,Linda AU - Lu,Yongju AU - Shi,Xianglin DA - 2010/01/01 DO - 10.3892/ijo_00000475 EP - 67 IS - 1 JO - Int J Oncol PY - 2010 SN - 1019-6439 1791-2423 SP - 59 ST - Inhibition of AP-1 and MAPK signaling and activation of Nrf2/ARE pathway by quercitrin T2 - International Journal of Oncology TI - Inhibition of AP-1 and MAPK signaling and activation of Nrf2/ARE pathway by quercitrin UR - https://doi.org/10.3892/ijo_00000475 VL - 36 ER -