Supplemental Figure 7 20 15 % of viable cells 10 5 RHPS4 RHPS4+GPI RHPS4 RHPS4+GPI Figure Legend: 5 x 104 W138 VA13/2RA ALT SV40-transformed fibroblasts were seeded in 60-mm Petri plates and 24 h after plating, were treated with 0.5 M RHPS4 in the presence or absence of GPI 15427 (GPI) PARP inhibitor. Cell counts (Coulter Counter, Kontron Instruments) and viability (trypan blue dye exclusion) were determined daily, from day 1 to day 8 of culture. The histogram shows the percentage of viable cells vs untreated cells analyzed at day 7 of culture.The mean of three independent experiments with comparable results is shown. Error bars indicate SD.