Liver Cancer
Copyright ©2006 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Apr 28, 2006; 12(16): 2517-2522
Published online Apr 28, 2006. doi: 10.3748/wjg.v12.i16.2517
Anticancer and cytotoxic properties of the latex of Calotropis procera in a transgenic mouse model of hepatocellular carcinoma
Tenzin Choedon, Ganeshan Mathan, Soneera Arya, Vijay L Kumar, Vijay Kumar
Tenzin Choedon, Ganeshan Mathan, Vijay Kumar, Virology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi - 110067, India
Soneera Arya, Vijay L Kumar, Department of Pharmacology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi -110029, India
Author contributions: All authors contributed equally to the work.
Supported by the core grant of International Centre for Genetic Engineering and Biotechnology. New Delhi
Correspondence to: Dr. Vijay Kumar, Virology Group, International Centre for Genetic Engineering and Biotechnology, PO Box 10504, Aruna Asaf Ali Marg, New Delhi - 110067, India. vijay@icgeb.res.in
Telephone: +91-11-26176680 Fax: +91-11-26162316
Received: October 4, 2005
Revised: October 25, 2005
Accepted: November 10, 2005
Published online: April 28, 2006
Abstract

AIM: To evaluate the anticancer property of the dried latex (DL) of Calotropis procera, a tropical medicinal plant, in the X15-myc transgenic mouse model of hepatocellular carcinoma and to elucidate its mechanism of action in cell culture.

METHODS: The young transgenic mice were orally fed with the aqueous suspension of DL (400 mg/kg for 5 d/wk) for 15 wk and their liver was examined for histopathological changes at 20 wk. Serum levels of vascular endothelial growth factor (VEGF) were also measured in these animals. To characterize the active fraction, DL was extracted with petroleum ether followed by methanol. The methanolic extract was sub-fractionated on a silica gel G column using a combination of non-polar and polar solvents and eleven fractions were obtained. Each fraction was analysed for cytotoxic effect on hepatoma (Huh7) and non-hepatoma (COS-1) cell lines and non-transformed hepatocytes (AML12) using tetrazolium (MTT) assay. Finally, the mechanism of cell death was investigated by measuring the levels of Bcl2, caspase 3 and DNA fragmentation.

RESULTS: DL treatment of mice showed a complete protection against hepatocarcinogenesis. No adverse effect was observed in these animals. The serum VEGF level was significantly lowered in the treated mice as compared to control animals. Cell culture studies revealed that the methanolic extract of DL as well as its fraction 8 induced extensive cell death in both Huh-7 and COS-1 cells while AML12 cells were spared. This was accompanied by extensive fragmentation of DNA in Huh-7 and COS-1 cells. No change in the levels of canonical markers of apoptosis such as Bcl2 and caspase 3 was observed.

CONCLUSION: DL of C. procera has the potential for anti-cancer therapy due to its differentiable targets and non-interference with regular pathway of apoptosis.

Keywords: Calotropis procera; Transgenic mice; Hepatocellular carcinoma; Cytotoxicity; Anticancer agent; Differential killing