Ovarian cancer is the most lethal gynecological malignancy and the seventh most common cancer worldwide. Current diagnosis options for ovarian cancer suffer from a lack of sensitivity and specificity that lead to either over-diagnosis or missed cancers. Ovarian cancer due to its often-asymptomatic nature in the early stages, leads to late diagnosis and limited treatment options. Therefore, there is an urgent need for the development of sensitive and specific assays involving minimally invasive techniques.

The primary aim of this doctoral thesis was to identify and validate promising novel biomarkers for ovarian cancer diagnosis. The aim was also to explore possibilities to develop a simple assay for the detection of cancer-associated glycoforms directly from human biofluids without any extensive preprocessing. The different studies focused on the development of a europium chelate-labeled nanoparticles (Eu-NPs)- aided immunoassay approach that uses glycan-based markers and their potential combinations for the detection of altered glycans of cancer patients. Several cancer-associated glycoprotein markers in combination with antibodies and lectins were tested to find the best functional biomarkers and their corresponding potential assays. The biomarker assays could significantly discriminate ovarian cancer from benign and healthy controls.

The result of this thesis presents several promising glycovariant biomarkers with a sensitive nanoparticle-based immunoassay approach for the diagnosis of ovarian cancer from unprocessed samples. This assay concept is robust, time-sensitive, requires minimal sample amounts and can be easily adapted to clinical settings and thus presents itself as a promising diagnostic test platform for ovarian cancer.