As shown in Fig.6D, the protein levels of PLK1, CDC25C, CyclinB1, CDC2 and p-AKT/AKT were significantly decreased in tumor tissue of LAS treated group compared to that of negative controls, which was consistent with the data shown in Fig. 4G. Taken together, our data demonstrate that LAS exerts its anti-tumor effect against breast cancer by suppressing PLK1 signaling. The gene discussed is PLK1; the disease is breast cancer.