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Sundfeldt, K.

Publications and source records attributed to Sundfeldt, K..

2 recordsLinked to original sources

High throughput proteomics identifies 484 high-accuracy plasma protein biomarker signatures for ovarian cancer

Ovarian cancer is usually detected at a late stage with the 5-year survival at only 30-40%. Additional means for early detection and improved diagnosis are acutely needed. To search for novel biomarkers, we compared circulating plasma levels of 981 proteins in patients with ovarian cancer and benign tumours, using the proximity extension assay. A novel combinatorial strategy was developed for identification of multivariate biomarker signatures, resulting in 484 mutually exclusive models out of which 448 did not contain the present biomarker MUCIN-16. The top-ranking model consisted of 14 proteins and had a AUC=0.95, PPV=1.0, sensitivity=0.99 and specificity=1.0 for detection of stage III-IV ovarian cancer in the discovery data, and an AUC=0.89, PPV=0.93, sensitivity=0.89 and specificity=0.95 in the replication data. The novel plasma protein signature could be used to improve the diagnosis of women with adnexal ovarian mass or in screening to identify women that should be referred to specialized examination.

cancer biology

A subgroup of mitochondrial extracellular vesicles discovered in human melanoma tissues are detectable in patient blood

Extracellular vesicles (EVs), including exosomes and microvesicles, are secreted from all cells, and convey messages between cells in health and disease. However, the diversity of EV subpopulations are only beginning to be explored. Since EVs have been implicated in tumor microenvironmental communication, we started to determine the diversity of EVs specifically in this tissue. To do this, we isolated EVs directly from patient melanoma metastatic tissues. Using EV membrane isolation and mass spectrometry analysis, we discovered enrichment of mitochondrial membrane proteins in the melanoma tissue-derived EVs, compared to non-melanoma-derived EVs. Specifically, EVs positive for a combination of the two mitochondrial inner membrane proteins MT-CO2 (mitochondrial genome) and COX6c (nuclear genome) were detected in the plasma of melanoma patients, and in ovarian and breast cancer patients. Furthermore, this subpopulation of EVs, contains active mitochondrial enzymes. Our findings show that tumor tissues are enriched in EVs with mitochondrial proteins and enzymatic activity, and these EVs can be detected in blood.

cancer biology