Apoptotic mechanisms of octreotide on HepG2

Hepatocellular carcinoma (HCC) is the fifth most common malignancy in the world and is estimated to cause approximately half a million deaths annually. Undoubtedly, the best available treatment for all liver tumors is complete surgical resection. However, the synthetic somatostatin analogue octreotide has been found effective in inhibiting tumor growth in a variety of experimental models. It has been reported that octreotide inhibits the proliferation and induces apoptosis of different HCC cell lines in vitro. The mechanisms of apoptosis induction however are not well understood.

A research article published on January 21, 2011 in the World Journal of Gastroenterology addresses this question. The authors confirmed that octreotide inhibited HepG2 proliferation at a concentration of 10-8 mol/L. Interestingly, lower concentrations of octreotide increased proliferation and this is possibly an additional reason for divergent results in both clinical trials and in vitro studies of octreotide in HCC. Also, their results support the induction of a caspase-mediated apoptotic pathway by octreotide in HepG2 cells, implicating both a receptor-mediated and mitochondrial-apoptotic pathway.

The findings of the present study indicate that measurements of serum octreotide levels may be important, at least in clinical trials, to verify optimal therapeutic drug concentrations.

Reference: Tsagarakis NJ, Drygiannakis I, Batistakis AG, Kolios G, Kouroumalis EA. Octreotide induces caspase activation and apoptosis in human hepatoma HepG2 cells. World J Gastroenterol 2011;17(3): 313-321

http://www.wjgnet.com/1007-9327/full/v17/i3/313.htm

Correspondence to: George Kolios, MD, PhD, Laboratory of Pharmacology, School of Medicine, Democritus University of Thrace, Dragana, Alexandroupolis, 68100, Greece. gkolios@med.duth.gr

Telephone: +30-25510-30368 Fax: +30-25510-30368

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 2009 IF: 2.092. 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.