Considering how the previous data showed that DT may prolong the S phase of the cell cycle in prostate cancer cells after 6 h, we used a western blot assay to investigate its effect on these DNA damage proteins, phosphorylated (S1981)-ATM (p-ATM) and 푟H2AX, in DU145 cells and PC-3 cells. The gene discussed is ATM; the disease is prostate cancer.