Natural products are vastly utilized as a source of chemotherapeutic agents for human cancers. Kochia scopraia is traditionally used for the cure of urological and dermatological diseases. Recently, methanol extract of Kochia scoparia (MEKS) has been shown to have anti-cancer activity to various human cancers. However, there is no report demonstrating the anti-cancer activity of MEKS in human mucoepidermoid carcinoma (MEC) cells. In this study, the authors studied the effects of MEKS on the cell proliferation and underlying mechanism in YD15 human MEC cells. MEKS decreased YD15 cell proliferation proven by trypan blue exclusion assay and induced apoptosis, evidenced by cell cycle analysis and western blotting. Autophagy induction by MEKS was verified by western blotting. In addition, MEKS regulated the expression of phosphorylated Akt, phosphorylated p38 and Nrf2 protein. This results can imply that MEKS might be a potential candidate for the treatment of human MEC cells.

The fruit of Kochia scoparia Scharder is traditionally used as a medicinal ingredient to treat allergic skin diseases and inflammatory diseases in China, Japan and Korea. Recently, several studies reported that K. scoparia had potential for the cytotoxicity of human cancer cells. To investigate the anti-cancer effect of K. scoparia on oral cancer and to determine the specific type of cell death induced by MEKS treatment. We investigated the anti-cancer effects of K. scoparia, methanol extract (MEKS) in HSC4 human oral cancer cells. We examined the effects of MEKS on the proliferation rate, cell cycle arrest, 7-AAD-ANNEXIN V double stain, reactive oxygen species (ROS) generation and activation of apoptosis and necroptosis-associated proteins in HSC4 cells. MTT assay results demonstrated that MEKS decreased the proliferation rates of HSC4 cells in a dose-dependent manner with an IC50 value of 45.3 μg/ml. MEKS at 50 μg/ml significantly increased the sub-G1 DNA contents of HSC4 cells to 84.8%, versus untreated cells. However, the activation of apoptosis-associated proteins such as cleaved caspase 3, cleaved caspase 8, cleaved caspase 9 and cleaved Poly (ADP-ribose) polymerase (PARP) did not detect. The level of Bax protein markedly increased in MEKS-treated HSC4 cells. In addition, the cell viability of the DPQ pre-treated HSC4 cells with MEKS treatment was significantly greater than that of MEKS treated-cells. These results suggest that MEKS inhibits cell proliferation and induces necroptosis in oral cancer cells and that MEKS may have potential chemotherapeutic value for the treatment of human oral cancer.