Essential Oil Extracted from Rhizoma of Atractylode Lancea Induces Oncosis in Human MKN-45 Cancer Cells

The aim of this study was to examine whether the essential oil extracted from rhizoma of Atractylode lancea has cytotoxicity to human MKN-45 cancer cells and its underlying mechanisms. The cytotoxicity of essential oil to cancer cells was examined by MTT assay. The effects of essential oil and disruption were monitored using whole-cell, time-lapse recording by microscopy. The effects of essential oil on cytoskeletal systems were detected by Western blotting and immunofluorescence. The effects of essential oil on cytokine secretion were measured by ELISA. The result showed that the cytotoxicity of essential oil was triggered rapidly by 2 μl/ml (1 h caused 50% maximum cytotoxicity) and involved secretion function perturbation. In addition, essential oil could induce membrane blebbing within 1 h of sustained application, which was blocked by polyethylene glycols (PEG) with molecular weights £3350, but not prevented by PEG with molecular weight34000 and extracellular calcium chelator EGTA. Moreover, essential oil did not disrupt cytoskeletal systems as demonstrated with no degradation of microtubules and actin. In conclusion, essential oil extracted from rhizoma of Atractylode lancea can rapidly initiate acute injury and burst via oncosis and may offer a novel therapeutic strategy for cancer treatment.