Colchicine-induced apoptosis in human normal liver L-02 cells by mitochondrial mediated pathways

New Drug Screening Center, China Pharmaceutical University, Nanjing 210009, Jiangsu, China.
Toxicology in Vitro (Impact Factor: 2.9). 02/2012; 26(5):649-55. DOI: 10.1016/j.tiv.2012.01.024
Source: PubMed


Colchicine is an alkaloid that has been widely used to treat gout. It also has a curative effect on cancer. Although many studies have shown that its effect on cell apoptosis was mediated by the activation of caspase-3, the pathways involved in the process remained obscure. Here we show some evidence regarding the missing information using human normal liver cells L-02 in our study. The effect of colchicine on apoptosis in L-02 cells and the apoptosis-associated signaling pathways were determined using different tests including cell viability assay, Annexin V and propidium idodide binding, PI staining, Hoechst 33342 staining, mitochondrial membrane potential assay, caspase activity assay and Western blot analysis. We found that colchicine-induced a dose-dependent drop of cell viability in L-02 cells; early apoptosis happened when cells were treated with 0.1μM of colchicine. The colchicine-induced loss of mitochondrial membrane potential, activation of caspase-3 and 9, up-regulation of Bax and down-regulation of Bcl-2 showed an evidence for the colchicine activity on apoptosis, at least, by acting via the intrinsic apoptotic pathway.

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    • "At this concentration it was also not highly effective against clonogenic cells. It has been shown recently that colchicine exerted anti-proliferative effect in hepatocellular carcinoma cell lines [77], but the significance of this finding is diminished by observation that it also reduced viability in normal liver cells [78]. Given these results, colchicine is probably not a good drug candidate for the treatment of melanoma. "
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