Figure 7.

Cell cycle progression in parental and 5-FU-resistant HCT116 cell lines in response to 5-FU treatment for 24 hours: (a) cell cycle distributions showing G₁/S boundary arrests at 8 hours and S phase arrests at 24 hours, showing S phase arrests at 24 hours; (b)-(d) G₁, S and G₂M fractions in all cell lines at 8 and 24 hours after 5-FU addition.