Antitumor Activity of Dichloromethane Extract from Salvia plebeia and Induction of Apoptosis on K562 Cells
Apoptosis or programmed cell death is a normal physiological process serving to eliminate unwanted cells and maintain homeostasis in healthy tissues. Tumour growth is regulated by the balance between cell proliferation and apoptosis. Deregulated cell proliferation and suppressed cell death together provide the underlying platform for neoplastic progression (Evan and Vousden, 2001; Kaufmann and Earnshaw, 2000). One essential strategy for cancer therapy is to target the lesions that suppress apoptosis in the tumor cells. It has been found that most cancer chemotherapy drugs exert cytotoxic effects on malignant cells by inducing apoptosis (Kaufmann and Earnshaw, 2000). In search for new cancer therapeutics, the herbs used in traditional medicines for cancer treatment are promising candidates.
The five different extracts prepared from S. plebeian have shown anti-tumour activities and preliminary studies have found that the dichloromethane (CH2Cl2 or methylene chloride) extract exhibited significant anti-tumour activities. Hence, the CH2Cl2 extract has been further analysed by testing its apoptotic induction on K562 myelogenous leukaemia line.
The CH2Cl2 extract showed the most potent cytotoxic effect against K562 cells, with an IC50 < 15 μg/mL for 3 d treatment. The characteristic apoptotic symptoms such as DNA fragmentation and chromatin condensation were also observed in the K562 cells.
Conclusion: The CH2Cl2 extract from S. plebeia may inhibit the cancer cell proliferation by inducing cell apoptosis on SGC-7901 gastric adenocarcinoma cells, K562 myelogenous leukaemia cells and DU-145 prostate cancer cells.
Ren J et al. Chinese Herbal Medicines, 2010, 3(1): 36-40. DOI: 10.3969/j.issn.1674-6384.2011.01.008
Evan GI, Vousden KH, 2001. Proliferation, cell cycle and apoptosis in cancer. Nature 411: 342-348.
Kaufmann SH, Earnshaw WC, 2000. Induction of apoptosis by cancer chemotherapy. Exp Cell Res 256: 42-49.