Brief Article
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World J Gastroenterol. Aug 21, 2012; 18(31): 4162-4168
Published online Aug 21, 2012. doi: 10.3748/wjg.v18.i31.4162
Growth inhibitory effects of Phyllanthus niruri extracts in combination with cisplatin on cancer cell lines
Raimundo Fernandes Araújo Júnior, Luiz Alberto Lira Soares, Cínthia Raquel da Costa Porto, Ranniere Gurgel Furtado de Aquino, Hugo Gonçalo Guedes, Pedro Ros Petrovick, Tatiane Pereira de Souza, Aurigena Antunes Araújo, Gerlane Coelho Bernardo Guerra
Ranniere Gurgel Furtado de Aquino, Hugo Gonçalo Guedes, Raimundo Fernandes de Araújo Júnior, Department of Morphology/Postgraduate Program in Morphological Sciences, Federal University of Rio Grande do Norte, Natal 59072-970, Rio Grande do Norte, Brazil
Luiz Alberto Lira Soares, Postgraduate Program in Pharmaceutical Sciences, Federal University of Pernambuco, Recife 50670-901, Pernambuco, Brazil
Cínthia Raquel da Costa Porto, Postgraduate Program in Pharmaceutical Sciences, Federal University of Rio Grande do Norte, Natal 59012-570, Rio Grande do Norte, Brazil
Pedro Ros Petrovick, Department of Production and control of drugs, Federal University of Rio Grande do Sul, Porto Alegre 90610-000, Rio Grande do Sul, Brazil
Tatiane Pereira de Souza, Department of Food and Drug Administration, Federal University of Amazonas, Manaus 69077-000, Amazonas, Brazil
Gerlane Coelho Bernardo Guerra, Aurigena Antunes de Araújo, Department of Biophysics and Pharmacology, Federal University of Rio Grande do Norte, Natal 59072-970, Rio Grande do Norte, Brazil
Author contributions: Araújo Júnior RF and Guerra GCB designed the research; Araújo Júnior RF, Araújo AA and Guerra GCB performed the research; Soares LAL, Petrovick PR and de Souza TP contributed new reagents/analytic tools; Araújo Júnior RF, Guedes HG, da Costa Porto CR and de Aquino RGF analyzed the data; Araújo Júnior RF, Guedes HG, da Costa Porto CR, Araújo AA, Guerra GCB wrote the paper.
Supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); CNPq (470179/2009-0) for financial support and Postgraduate Program in Pharmaceutical Sciences, Federal University of Rio Grande do Norte
Correspondence to: Gerlane Coelho Bernardo Guerra, PhD, Department of Biophysics and Pharmacology, Federal University of Rio Grande do Norte, Natal 59072-970, Rio Grande do Norte, Brazil. gerlaneguerra@hotmail.com
Telephone: +55-84-32153419 Fax: +55-84-33422200
Received: July 6, 2011
Revised: January 10, 2012
Accepted: May 12, 2012
Published online: August 21, 2012
Abstract

AIM: To investigate the cytotoxic effects of spray-dried extracts of Phyllanthus niruri in combination with cisplatin on two cancer cell lines.

METHODS: Colorectal carcinoma (HT29) and human hepatocellular carcinoma (HepG2) cells were treated with spray-dried extracts of Phyllanthus niruri (SDEPN) either alone or in combination with cisplatin at different concentrations (0.5 mg/mL and 1 mg/mL) for 4 h and 24 h. To verify and quantify cancer cells treated with these products as well as identify the cell cycle stage and cell viability, we stained the cells with propidium iodide and assessed them by flow cytometry. The percentage of cells in different cell cycle phases was quantified and data were expressed as histograms. Significant differences between groups were determined using analysis of variance and Bonferroni’s test, as indicated. A value of P < 0.05 was considered to be statistically significant.

RESULTS: SDEPN had significantly different cytotoxic effects on HT29 (2.81 ± 0.11 vs 3.51 ± 1.13, P > 0.05) and HepG2 (5.07 ± 0.3 vs 15.9 ± 1.04, P < 0.001) cells when compared to control cells for 4 h. SDEPN also had significantly different cytotoxic effects on HT29 (1.91 ± 0.57 vs 4.53 ± 1.22, P > 0.05) and HepG2 (14.56 ± 1.6 vs 35.67 ± 3.94, P < 0.001) cells when compared to control cells for 24 h. Both cell lines were killed by cisplatin in a dose-dependent manner compared to control cells (HepG2 cells for 4 h: 10.78 ± 1.58 vs 53.89 ± 1.53, P < 0.001; 24 h: 8.9 ± 1.43 vs 62.78 ± 1.87, P < 0.001 and HT29 cells for 4 h: 9.52 ± 0.913 vs 49.86 ± 2.89, P < 0.001; 24 h: 11.78 ± 1.05 vs 53.34 ± 2.65, P < 0.001). In HT29 cells, pretreatment with SDEPN and subsequent treatment with cisplatin resulted in a greater number of cells being killed (12.78 ± 1.01 vs 93.76 ± 1.6, P < 0.001). HepG2 cells showed significant cell killing with treatment with SDEPN when combined with cisplatin (12.87 ± 2.78 vs 78.8 ± 3.02, P < 0.001).

CONCLUSION: SDEPN is selectively toxic against two cancer cell lines. Moreover, SDEPN in combination with cisplatin induces a synergistic increase in the cell death of both HT29 and HepG2 cells.

Keywords: Cisplatin; Colorectal cancer; Liver cancer; Phyllanthus niruri; Cytotoxic effect