We found that proteins expression of CDC25C and p-AKT(T308) were significantly decreased in SK-BR-3 and MDA-MB-231 cells treated with LAS (1,3 μM) compared to that of controls, suggesting that LAS inhibited the phosphorylation of CDC25C and AKT via regulating PLK1 pathway in breast cancer cells. This evidence concerns the gene PLK1 and breast cancer.