To search proteins that interact with ANXA1, ANXA1 interactors were coimmunoprecipitated with anti-ANXA1 antibody from MB231 cell extracts, separated on SDS-PAGE and stained with Coomassie blue , and non-immune IgG antibody instead of anti-ANXA1 antibody served as control. All bands were excised, and subjected to in gel trypsin digestion and liquid chromatography and high-throughput mass spectrometry (LC-MS/MS) analysis.As a result, a total of 489 proteins including PARP1 were identified .