Department of Morphology/Postgraduate Program in Morphological Sciences, Federal University of Rio Grande do Norte, Natal 59072-970, Rio Grande do Norte, Brazil.
World J Gastroenterol. 2012 Aug 21;18(31):4162-6168. doi: 10.3748/wjg.v18.i31.4162.
To investigate the cytotoxic effects of spray-dried extracts of Phyllanthus niruri in combination with cisplatin on two cancer cell lines.
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.
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).
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.
研究叶下珠喷雾干燥提取物与顺铂联合对两种癌细胞系的细胞毒性作用。
采用不同浓度（0.5 mg/mL 和 1 mg/mL）的叶下珠喷雾干燥提取物（SDEPN）单独或联合顺铂处理结直肠癌细胞（HT29）和人肝癌细胞（HepG2）4 小时和 24 小时。用碘化丙啶染色处理过的癌细胞，并通过流式细胞术进行检测，以验证和量化癌细胞，并确定细胞周期阶段和细胞活力。不同细胞周期阶段的细胞百分比进行量化，并以柱状图表示数据。使用方差分析和 Bonferroni 检验确定组间的显著差异，如需要。P 值 < 0.05 被认为具有统计学意义。
与对照组相比，SDEPN 对 HT29（2.81 ± 0.11 对 3.51 ± 1.13，P > 0.05）和 HepG2（5.07 ± 0.3 对 15.9 ± 1.04，P < 0.001）细胞的细胞毒性作用在 4 小时时有显著差异。SDEPN 对 HT29（1.91 ± 0.57 对 4.53 ± 1.22，P > 0.05）和 HepG2（14.56 ± 1.6 对 35.67 ± 3.94，P < 0.001）细胞的细胞毒性作用在 24 小时时也有显著差异。与对照组相比，两种细胞系均被顺铂以剂量依赖性方式杀死（HepG2 细胞 4 小时：10.78 ± 1.58 对 53.89 ± 1.53，P < 0.001；24 小时：8.9 ± 1.43 对 62.78 ± 1.87，P < 0.001和 HT29 细胞 4 小时：9.52 ± 0.913 对 49.86 ± 2.89，P < 0.001；24 小时：11.78 ± 1.05 对 53.34 ± 2.65，P < 0.001）。在 HT29 细胞中，SDEPN 预处理后再用顺铂处理导致更多的细胞死亡（12.78 ± 1.01 对 93.76 ± 1.6，P < 0.001）。HepG2 细胞用 SDEPN 联合顺铂处理时显示出显著的细胞杀伤作用（12.87 ± 2.78 对 78.8 ± 3.02，P < 0.001）。
SDEPN 对两种癌细胞系具有选择性毒性。此外，SDEPN 联合顺铂诱导 HT29 和 HepG2 细胞死亡的协同增加。
