Cytotoxic Activity ofBoesenbergia rotundaExtracts against Nasopharyngeal Carcinoma Cells (HK1). Cardamonin, aBoesenbergia rotundaConstituent, Inhibits Growth and Migration of HK1 Cells by Inducing Caspase-Dependent Apoptosis and G2/M-Phase Arrest

Boesenbergia rotunda(L.) Mansf. is an edible herb that is commonly used in the cuisine of several Asian countries. Studies have shown that it possesses high bioactivity against a variety of cancer cells. In this study, we investigated the cytotoxic activity ofBoesenbergia rotundarhizomes and some of its constituents on nasopharyngeal carcinoma cells (HK1). MTT assay results showed that the methanolic and hexane extracts ofBoesenbergia rotundadecreased HK1 cell viability with IC(50)values of 136 mu g/ml and 66 mu g/ml, respectively. Cardamonin, a constituent ofBoesenbergia rotunda, exhibited the highest cytotoxic activity with an IC(50)value of 27 mu g/ml. Further studies on cardamonin revealed that it inhibited the migration of HK1 cells, caused G2/M-phase arrest and induced apoptosis. Apoptosis was inducedviaactivating caspase-8 and caspase-3, but independent of caspase-9. This indicated that cardamonin induced extrinsic apoptosis. Western blot analysis further showed that cardamonin caused extrinsic apoptosis, as the expression levels of intrinsic apoptosis-related proteins (Bcl-X-L, Bcl-2 and Bax), were not affected. Finally, JC-1 staining of HK1 cells revealed an increase in the mitochondrial membrane potential after treatment, further proving that cardamonin did not induce apoptosisviathe intrinsic pathway. These results reflect cardamonin's potential as an anticancer agent.

Automated summary

The study showed that the constituent cardamonin from Boesenbergia rotunda exhibited high cytotoxic activity against nasopharyngeal carcinoma cells, inhibiting cell migration and inducing apoptosis through activating the extrinsic pathway. This demonstrates cardamonin's potential as an anticancer agent.