In EC cell lines PARP maximal activity correlates with PARP1 protein expression.

<p>A) PARP maximal activity correlates with EC sensitivity to AZD2281. The maximal PARP activity was assayed <i>in vitro</i> by measuring the levels of PAR (poly[ADP-ribose])-polymers linked to PARP (autoribosilatyon) and histone H1 (a PARP-1 substrate), in presence of activated DNA (nuclease treated DNA). Data are mean value ± s.d. of three to four independent experiments. B) Representative image of a western blotting analysis of PARP-1 expression, in the indicated cell lines. β-tubulin was used as loading control. C) densitometric analysis of PARP1 expression in the indicated cell lines. Data are the mean value ± s.d. of five independent experiments. Results are presented as expression level respect to 27x-1 cell line, and normalized against the loading control (β-tubulin). Statistical analysis was performed using a unpaired two-tail Student’s t-test (P<0.05).