(C) MMS-treated cells, with or without Olaparib, were immunoprecipitated using an anti-EWS antibody and immunoblotted by anti-PAR antibody (upper). Pre-Olaparib group was treated with Olaparib for 3 hours before MMS treatment (0.02% 30 minutes) and after-Olaparib group treated Olaparib after 10 minutes following treatment of MMS. Lower blot indicates input of anti-EWS antibody. 