| Novel biomarkers for ovarian cancer are needed, as current biomarkers are inadequate due to low diagnostic sensitivity and specificity. We performed an in-depth proteomic analysis of ovarian cancer ascites using size exclusion chromatography and ultrafiltration focusing on low molecular mass proteins. 445 proteins were identified from the soluble ascites fraction by 2D-LC-MS/MS, 52 of which warranted further validation after applying filtration criteria. Preliminary verification and validation of candidates in serum identified nidogen-2, a basement membrane protein. Serum nidogen-2 concentration between normal and benign disease patients was not different, however, concentration in serum of ovarian cancer patients was elevated. Both nidogen-2 and CA125 were elevated more in the serous histotype of ovarian cancer and in late state disease. Both concentrations were strongly correlated. Nidogen-2 had an AUC ranging from 0.73 to 0.83 but AUC for CA125 was superior. Unfortunately, neither markers could complement the other in increasing the AUC. |
