Figure 2.

SN-38 inhibits the expression of survivin. A. Time-dependent inhibition of survivin expression by SN38 in MCF-7 cells. Cells were treated with SN-38 (0.3 μM) for 2 hours and then without drug for additional hours as indicated. Cells were then lysed and survivin expression was determined by western blots. B. A low concentration of SN-38 shows a better inhibitory effect on survivin expression in comparison with a relative high concentration of SN-38. C and D. Different breast cancer cell lines were treated with SN-38 for 16 hours with different concentration of SN-38 as indicated, following by western blots. β–Actin was used in all experiments as internal controls (A –D).