10567 Background: Study was designed to identify biomarker candidate proteins (bcp) in discovery phase and validate them in confirmation phase using serum samples from healthy control and epithelial ovarian cancer (EOC) patients. Then bcp's were examined in EOC patients in context of current disease status; during chemotherapy treatments (c), remission (RM), and recurrence (RC). Methods: We combined mass spectrometry-based Multidimensional Protein Identification Technology (MUDPIT) proteomics strategy with high throughput Multiplex beads-based LUMINEX assay and enzyme-linked immunosorbent assay (ELISA) to identify and validate the bcps in serum. 88 healthy controls and 83 EOC patients were analyzed; 18 during chemotherapy, 28 in remission and 34 with recurrent disease. Results: Expression levels of acute phase protein Serum amyloid A (SAA), C-reactive protein (CRP), alpha 1 antitrypsin (SERPINA1), secreted phosphoprotein 1 (SSP1), and matrix metallopeptidase 1 (MMP1) were increased in cancer patients, while chemokine ligand 2 (CCL2) showed lower expression level in the cancer samples versus controls (Table). Elevated serum levels of CRP (p=0.027)and MMP1(p=0.015) were associated with cancer recurrence when compared to remission. Conclusions: Serum levels of bcps SAA, MMP1, CRP, SSP1, SERPINA1, and CCL2 were significantly changed in cancer and some protein level changes correspond to EOC clinical status. These bcp's may be important in CA125 negative patients and deserve further study. Symbol Study phases RC/control p C/control p RC + C/control p RC/RM p SAA MS discovery 2.62 0.0272 1.89 0.2664 2.24 0.0400 2.93 0.0112 ELISA/LUMINEX confirmation 3.37 0.0212 4.59 0.0956 3.80 0.0055 2.30 0.0748 SERPINA1 MS discovery 2.01 0.1814 3.29 0.0067 2.68 0.0157 0.84 0.6201 ELISA/LUMINEX confirmation 1.18 0.0343 1.31 0.02 1.23 0.0027 0.82 0.0871 CRP MS discovery 4.93 0.0016 6.00 0.0019 5.49 0.0000 2.98 0.0081 ELISA/LUMINEX confirmation 4.09 0.0003 5.38 0.0172 4.54 0.0000 2.03 0.0270 SPP1 ELISA/LUMINEX confirmation 2.51 0.0004 3.12 0.1100 2.72 0.0013 1.48 0.1089 MMP1 ELISA/LUMINEX confirmation 1.90 0.0005 1.80 0.0183 1.86 0.0000 1.56 0.0159 CCL2 ELISA/LUMINEX confirmation 0.80 0.0445 1.17 0.4893 0.93 0.5348 0.87 0.3513 No significant financial relationships to disclose.