A diagnostic reagent or device comprises at least one ligand capable of specifically complexing with, binding to, or quantitatively detecting or identifying the biomarker chloride intracellular channel protein 4 (CLIC4) or an isoform, pro-form, modified molecular form including posttranslational modification, or unique peptide fragment or nucleic acid fragment thereof. An alternative diagnostic reagent or device comprises ligand or ligands capable of specifically complexing with, binding to, or quantitatively detecting or identifying multiple tropomyosin biomarkers. Optionally, such reagent or device includes a signaling molecule and/or a substrate on which the ligand is immobilized. Other reagents and methods of diagnosing ovarian cancer include use of CLIC4 ligands and/or multiple tropomyosin ligands with an additional ovarian cancer biomarker. For example, CLIC4 combined with one or more of CLIC1 and/or one or multiple members of the tropomyosin family, e.g., TPM1, TPM2, TPM3 or TPM4, and further optionally including CTSD-30 kDa and/or PRDX-6, among other ovarian cancer biomarkers can form a characteristic diagnostic pattern or profile of expression that is diagnostic of the disease. Still other embodiments are described.