Effects of LY on epithelial cancer cells. (a) Growth curves of MCF7, A-375, HCT116, and DLD1 cells. Cells were trypsinized at the indicated time points and cell numbers were determined. (b) Induction of p21 protein after treatment with LY. HCT116 colorectal cancer cells were treated with 1.5 μM LY for the indicated periods. Cell lysates were prepared and subjected to Western blot analysis. For details, see the Methods.