Apoptotic effect of citrus fruit extract nobiletin on lung cancer cell line A549 in vitro and in vivo

Abstract

Lung cancer is the leading cause for cancer-related death worldwide and the effectiveness of current treatments is very limited. Here we reported that Nobiletin, an effective component of citrus fruit, has antiproliferative activity on lung cancer cells both in vitro and in vivo. Cell viability and clonogenic assay showed that Nobiletin dose-dependently suppressed the proliferation of human lung adenocarcinoma cell line A549 cells, while has having a minimal effect on human umbilical vein endothelial cell line ECV-304 cells. DNA fragment assay and comet assay demonstrated that Nobiletin induced A549 cell apoptosis. Nobiletin-induced cell cycle arrest at G2/M phase was detected by Flow cytometric analysis. In addition, western blot analysis revealed that A549 cells pretreated with Nobiletin showed decreased Bcl-2 and increased Bax protein expression, which were positively correlated with elevated expression of p53 compared to control. Furthermore, Nobiletin had overt inhibitory effect on the tumor growth in nude mice model was observed in vivo. Taken together, these results suggest that Nobiletin could induce p53-mediated cell cycle arrest and apoptosis via modulated the Bax:Bcl-2 protein ratio, is effective as a potent antitumor agent on lung tumors.