Liver Cancer
Copyright ©2008 The WJG Press and Baishideng. All rights reserved.
World J Gastroenterol. Mar 14, 2008; 14(10): 1491-1497
Published online Mar 14, 2008. doi: 10.3748/wjg.14.1491
Synergistic growth inhibitory effects of Phyllanthus emblica and Terminalia bellerica extracts with conventional cytotoxic agents: Doxorubicin and cisplatin against human hepatocellular carcinoma and lung cancer cells
Khosit Pinmai, Sriharut Chunlaratthanabhorn, Chatri Ngamkitidechakul, Noppamas Soonthornchareon, Chariya Hahnvajanawong
Khosit Pinmai, Sriharut Chunlaratthanabhorn, Department of Preclinical Science, Faculty of Medicine, Thammasat University, Pathumthani 12120, Thailand
Chatri Ngamkitidechakul, Department of Biochemistry, Faculty of Medicine, Chiang Mai University, Muang, Chiang Mai 50200, Thailand
Noppamas Soonthornchareon, Department of Pharmacognosy, Faculty of Pharmacy, Mahidol University, Bangkok 10400, Thailand
Chariya Hahnvajanawong, Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand
Author contributions: Khosit P contributed to this work; Khosit P, Chatri N, and Chariya H designed research; Chariya H provided SRB technique; Khosit P performed research; Sriharut C, Chatri N and Noppamas S contributed new reagents/analytic tools; Khosit P, and Chariya H analyzed data; and Khosit P, and Chariya H wrote the paper.
Correspondence to: Khosit Pinmai, Department of Preclinical Science, Faculty of Medicine, Thammasat University, Paholyotin Rd., Amphur Klongluang, Pathumthani 12120, Thailand. all_sants@hotmail.com
Telephone: +66-292-69736
Fax: +66-292-69711
Received: August 29, 2007
Revised: January 25, 2008
Published online: March 14, 2008
Abstract

AIM: To examine the growth inhibitory effects of Phyllanthus emblica (P. emblica) and Terminalia bellerica (T. bellerica) extracts on human hepatocellular carcinoma (HepG2), and lung carcinoma (A549) cells and their synergistic effect with doxorubicin or cisplatin.

METHODS: HepG2 and A549 cells were treated with P. emblica and T. bellerica extracts either alone or in combination with doxorubicin or cisplatin and effects on cell growth were determined using the sulforhodamine B (SRB) assay. The isobologram and combination index (CI) method of Chou-Talalay were used to evaluate interactions between plant extracts and drugs.

RESULTS: P. emblica and T. bellerica extracts demonstrated growth inhibitory activity, with a certain degree of selectivity against the two cancer cell lines tested. Synergistic effects (CI < 1) for P. emblica/doxorubicin or cisplatin at different dose levels were demonstrated in A549 and HepG2 cells. The T. bellerica/cisplatin or doxorubicin also showed synergistic effects in A549 and HepG2 cells. In some instances, the combinations resulted in antagonistic effects. The dose reduction level was different and specific to each combination and cell line.

CONCLUSION: The growth inhibitory activity of doxorubicin or cisplatin, as a single agent, may be modified by combinations of P. emblica or T. bellerica extracts and be synergistically enhanced in some cases. Depending on the combination ratio, the doses for each drug for a given degree of effect in the combination may be reduced. The mechanisms involved in this interaction between chemotherapeutic drugs and plant extracts remain unclear and should be further evaluated.

Keywords: Cisplatin, Doxorubicin, Liver cancer, Phyllanthus emblica, Synergistic effect, Terminalia bellerica