Table 1. Effect of rucaparib on Topo I poison (CPT)-induced cytotoxicity in LoVo cells elutriated and separated into G1, S, and G2 cell cycle phase-enriched fractions.

	% Survival
	G1	S	G2
30 nM CPT	53.2	36.1	57.4
30 nM+AG014699	58.3	21.9	57.5
Potentiation factor (at 50% survival)	0.9	1.6*	1
100 nM CPT	45.3	26	58.5
100 nM+AG014699	59.3	13.6	53.6
Potentiation factor (at 50% survival)	0.8	1.9*	1.1

Abbreviations: CPT=camptothecin; Topo I=topoisomerase I. Cells were separated by centrifugal elutriation into G1, S, and G2 phases prior to drug treatment. Data are means from 2 to 3 replicates in a single experiment where LoVo cells were elutriated and then treated for 1 h with CPT±rucaparib before plating for colony formation. *P<0.05, other figures in bold are not significant.