Article

Effect of selected phytochemicals on cell proliferation in A549 lung cancer cells

Food science and biotechnology (Impact Factor: 0.66). 19(4):1063-1068. DOI: 10.1007/s10068-010-0149-0

ABSTRACT Effects of quercetin 3-β-d-glucoside, resveratrol, and curcumin on A549 lung cancer cell proliferation and the mechanism of these phytochemicals in
regulating apoptosis and cell cycle arrest were investigated. A549 cells were treated with quercetin 3-β-d-glucoside, resveratrol, or curcumin at 37°C for 96 hr and cell viability was measured with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium
bromide (MTT) assay. Proteins related to apoptosis and cell cycle in A549 cells were quantified with Western blotting assay.
Quercetin 3-β-d-glucoside, resveratrol, and curcumin inhibited A549 cell proliferation in a dose-dependent manner (p<0.05). Quercetin 3-β-Dglucoside significantly decrease the expression level of CDK4 at concentrations of 5 mM and above (p<0.05). Curcumin lowered expression level of Bcl-2, CDK4, and cyclin D1 at concentrations of 100, 50, and above, and 50 mM
and above, respectively (p<0.05). These results suggest that phytochemicals, which can be found in a normal diet, inhibit lung cancer cell proliferation
and regulate the expression of the proteins involved in apoptosis and cell cycle.

Keywordslung cancer-A549 cell-quercetin 3-β-Dglucoside-resveratrol-curcumin

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