Proteomic biomarkers for overall and progression-free survival in ovarian cancer patients

Purpose: To determine if the level of apolipoprotein A1, hepcidin, transferrin, inter-a trypsin IV internal fragment, transthyretin (TT), connective-tissue activating protein 3 (CTAP3), serum amyloid A1, beta-2 microglobulin (B2M) might have impact on overall and progression-free survival for ovarian cancer (OC) patients. Experimental design: Serum from 150 OC patients was tested using SELDI-TOF-MS. Results: A proteomic prognostic index (xb-pro) was constructed using the regression coefficients based on inter-alpha trypsin IV internal fragment, B2M and TT. A multivariable Cox survival analysis including the xb-pro index showed that xb-pro (p<0.0001, HR = 2.50, 95% CI: 1.65-3.79), residual tumor after primary surgery (p = 0.0005), age (p = 0.01) and chemotherapy (p = 0.0002) are of independent prognostic value for overall survival. International Federation of Gynecology and Obstetrics stage, performance status, histological type of tumor and serum CA125 were found of no independent value. A proteomic index (xb-pfs) based on B2M and CTAP3 was found to predict progression-free survival (xb-pfs: p = 0.008, HR = 1.77, 95% CI: 1.17-2.70 together with type of surgery, age and chemotherapy. Conclusions and clinical relevance: We found an index with three proteomic biomarkers (xb-pro) to be of independent prognostic value for overall survival and an index with two proteomic biomarkers (xb-pfs) with evidence of independent prognostic value for progression-free survival.