Fol. Biol. 2017, 63, 155-163
Oridonin Induces Apoptosis in Human Nasopharyngeal Carcinoma Cells Involving ROS Generation
Oridonin, an ent-kaurene diterpenoid isolated from the traditional Chinese herb Rabdosia rubescens, has been reported to be a potent cytotoxic agent against a wide array of cancer cells. However, its effect on human nasopharyngeal carcinoma (NPC) cells has not been well investigated. The present study aimed to explore the anti-tumour effect of oridonin in NPC cells and its underlying mechanisms. Cell viability was examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay and colony formation assay. Apoptosis, mitochondrial membrane potential (MMP), reactive oxygen species (ROS), and expression of apoptosis-related proteins were analysed by flow cytometry with propidium iodide staining, JC-1 staining, DCFH-DA staining, and Western blot analysis, respectively. The results showed that oridonin concentration-dependently inhibited the cell viability, decreased the colony formation, and enhanced the apoptotic rate in NPC cells. Further, oridonin-induced apoptosis was mediated by the mitochondrial pathway in NPC cells, which was confirmed by the loss of MMP, downregulation of anti-apoptotic Bcl-2 family protein Mcl-1 and Bcl-2, upregulation of pro-apoptotic Bcl-2 family member Bax, and activation of caspase-3 and PARP. Notably, the augmented ROS generation played an essential role in oridonin-induced apoptosis in NPC cells, as the apoptosis-inducing effect was attenuated by ROS scavenger N-acetyl-L-cysteine. These results indicate that oridonin triggers apoptosis through the ROSmediated mitochondrial pathway in NPC cells. This study supports oridonin to be an interesting candidate drug for the treatment of human NPC.
Keywords
nasopharyngeal carcinoma, oridonin, apoptosis, reactive oxygen species.
Funding
This work was supported by the National Natural Science Foundation of China (81372899, 81603155), the Natural Science Foundation of Anhui Province (1708085QH212), the Project of Natural Science Research for College and University of Anhui Province (KJ2016A486, KJ2016SD39, KJ2017A230), and the Natural Science Foundation of Bengbu Medical College (BYKY1408ZD, BYKY1606ZD).
References
Copyright
This is an open-access article distributed under the terms of the Creative Commons Attribution License.