In vitro antitumor activity of the ethyl acetate extract of Potentilla chinensis in osteosarcoma cancer cells

The aim of the current study was to evaluate the anticancer effect of the ethanol extract of Potentilla chinensis, a Chinese medicinal plant. An MTT assay was used to evaluate the cell viability of MG-63 human osteosarcoma cancer cells and fR-2 cells. Furthermore, the effect of the extract on apoptosis induction, cell cycle phase distribution and inhibition of cell migration in the MG63 human osteosarcoma cancer cell line was evaluated. The effect of the extract on cell cycle phase distribution was assessed by flow cytometry using propidium iodide (PI). Phase contrast microscopy detected the morphological changes in MG63 cancer cells following extract treatment. The results of the study demonstrated that the extract was cytotoxic to MG63 cancer cells, while the normal cell line (epithelial cell line) showed lower susceptibility. Phase contrast microscopy showed distinguishing morphological features, such as cell shrinkage and blebbing induced by the extract treatment in osteosarcoma cancer cells. The average proportion of Annexin V-positive cells (total apoptotic cells) significantly increased from 5.6% in the control to 24.2, 38.8 and 55.7% in the 40, 80 and 150 µg/ml groups, respectively. The extract induced early and late apoptosis in the cancer cells. Flow cytometric analysis revealed that the extract induced G0/G1-cell cycle arrest, which also showed significant dose-dependence. The extract induced a significant and concentration-dependent reduction in cell migration. Moreover, DNA fragmentation was also examined by observation of the formation of DNA ladders. It was demonstrated that DNA fragmentation was increased with extract concentration compared with that in the control. Taken together, EEPC may serve as potential therapeutic agent against osteosarcoma, provided that the toxicity profile and in vivo investigations demonstrate that it is safe.