Primary research

Intrinsic anticarcinogenic effects of Piper sarmentosum ethanolic extract on a human hepatoma cell line

Shahrul Hisham Zainal Ariffin¹ , Wan Haifa Haryani Wan Omar¹ , Zaidah Zainal Ariffin² , Muhd Fauzi Safian² , Sahidan Senafi¹ and Rohaya Megat Abdul Wahab³

¹  School of Bioscience and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600, Selangor Darul Ehsan, Malaysia

²  Department of Microbiology, Faculty of Applied Science, Universiti Teknologi MARA, 40450, Shah Alam, Selangor, Malaysia

³  Department of Orthodontic, Faculty of Dentistry, Universiti Kebangsaan Malaysia, 50300, Kuala Lumpur, Malaysia

author email corresponding author email

Cancer Cell International 2009, 9:6doi:10.1186/1475-2867-9-6

Published:	3 March 2009

Abstract

Background

Piper sarmentosum, locally known as kaduk is belonging to the family of Piperaceae. It is our interest to evaluate their effect on human hepatoma cell line (HepG2) for the potential of anticarcinogenic activity.

Results

The anticarcinogenic activity of an ethanolic extract from Piper sarmentosum in HepG2 and non-malignant Chang's liver cell lines has been previously determined using (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide) (MTT) assays, where the IC₅₀ value was used as a parameter for cytotoxicity. The ethanolic extract that showed anticarcinogenic properties in HepG2 cells had an IC₅₀ of 12.5 μg mL^-1, while IC₅₀ values in the non-malignant Chang's liver cell line were greater than 30 μg mL^-1. Apoptotic morphological changes in HepG2 cells were observed using an inverted microscope and showed chromatin condensation, cell shrinkage and apoptotic bodies following May-Grunwald-Giemsa's staining. The percentage of apoptotic cells in the overall population (apoptotic index) showed a continuously significant increase (p < 0.05) in 12.5 μg mL^-1 ethanolic extract-treated cells at 24, 48 and 72 hours compared to controls (untreated cells). Following acridine orange and ethidium bromide staining, treatment with 10, 12 and 14 μg mL^-1 of ethanolic extracts caused typical apoptotic morphological changes in HepG2 cells. Molecular analysis of DNA fragmentation was used to examine intrinsic apoptosis induced by the ethanolic extracts. These results showed a typical intrinsic apoptotic characterisation, which included fragmentation of nuclear DNA in ethanolic extract-treated HepG2 cells. However, the non-malignant Chang's liver cell line produced no DNA fragmentation. In addition, the DNA genome was similarly intact for both the untreated non-malignant Chang's liver and HepG2 cell lines.

Conclusion

Therefore, our results suggest that the ethanolic extract from P. sarmentosum induced anticarcinogenic activity through an intrinsic apoptosis pathway in HepG2 cells in vitro.