Fig. 5.

Inhibition of FEN1 retarded DNA replication and led to the accumulation of DNA damage. a. Thymidine incorporation assay. b. Cell growth assay. c. FACS to determine the effects of SC13 on cell cycle profile. Cell staining by γ-H2AX. Western blotting assay to determine the γ-H2AX level before and after SC13 treatment in (d) MCF7, (e) MDA-MB-231, (f) Bcap37 and (g) MCF10A cells. h. Cell staining to determine γ-H2AX foci in MCF7 cells treated by SC13 (20 μM and 50 uM), or (i) with co-treatment by SC13 (10 μM) and PARP inhibitor (10 μM). j. Effect of SC13-induced FEN1 inhibition on the induction of genome instability. Giemsa-stained metaphase spreads showing the chromosomal breaks generated upon SC13 treatment.