A new light on the anti-tumor mechanisms of Scutellaria barbata

Medicinal plants have been used as traditional remedies for hundreds of years. Among them, S. barbata has been traditionally used in treatment of hepatitis, inflammation, osteomyelitis and gynecological diseases in China. Studies indicate that extracts from S. barbata have growth inhibitory effects on a number of human cancers. Reports are available on the treatment of lung, breast and digestive system cancer, hepatoma, and chorioepithelioma with S. barbata extracts. However, the underlying mechanism of the antitumor activity of S. barbata extracts remains unclear.

A research article to be published on December 28, 2008 in the World Journal of Gastroenterology addresses this question. The research team led by Dr. Zhi-Jun Dai from the Medical School of Xi'an Jiaotong University studied the growth inhibitory effects of S. barbata and determined its mechanism of antitumor activity in mouse liver cancer cell line H22.

They found that ESB could inhibit the proliferation of H22 cell in a time dependent manner. Among the various phases of cell cycle, the percentage of cells in S phase was significantly decreased, while the percentage of cells in G1 phase was increased. Flow cytometry assay also showed ESB had positive effect on apoptosis. Typical apoptotic morphology such as condensation and fragmentation of nuclei and blebbing membrane of the apoptotic cells could be observed through transmission electron microscope and fluorescence microscope. Further investigating the molecular mechanism behind ESB-induced apoptosis, cells treated with ESB underwent a rapid loss of mitochondrial transmembrane potential(delta psi m), release of mitochondrial cytochrome c into cytosol, induction of caspase-3 activity in a dose-dependent manner. This may offer new evidence for S. barbata in the treatment of hepatoma in clinical practice.

Reference: Dai ZJ, Wang XJ, Li ZF, Ji ZZ, Ren HT, Tang W, Liu XX, Kang HF, Guan HT, Song LQ. Scutellaria barbate extract induces apoptosis of hepatoma H22 cells via the mitochondrial pathway involving caspase-3. World J Gastroenterol 2008; 14(48): 7321-7328 http://www.wjgnet.com/1007-9327/14/7321.asp

Correspondence to: Dr. Zhi-Jun Dai, Department of Oncology, the Second Affiliated Hospital, Medical School of Xi'an Jiaotong University, No. 157, West 5th Road, Xi'an 710004, Shaanxi Province, China. dzj0911@126.com

World Journal of Gastroenterology (WJG), a leading international journal in gastroenterology and hepatology, has established a reputation for publishing first class research on esophageal cancer, gastric cancer, liver cancer, viral hepatitis, colorectal cancer, and H pylori infection and provides a forum for both clinicians and scientists. WJG has been indexed and abstracted in Current Contents/Clinical Medicine, Science Citation Index Expanded (also known as SciSearch) and Journal Citation Reports/Science Edition, Index Medicus, MEDLINE and PubMed, Chemical Abstracts, EMBASE/Excerpta Medica, Abstracts Journals, Nature Clinical Practice Gastroenterology and Hepatology, CAB Abstracts and Global Health. ISI JCR 2003-2000 IF: 3.318, 2.532, 1.445 and 0.993. WJG is a weekly journal published by WJG Press. The publication dates are the 7th, 14th, 21st, and 28th day of every month. WJG is supported by The National Natural Science Foundation of China, No. 30224801 and No. 30424812, and was founded with the name of China National Journal of New Gastroenterology on October 1, 1995, and renamed WJG on January 25, 1998.

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