Detection of glyco‐mucin profiles improves specificity of MUC16 and MUC1 biomarkers in ovarian serous tumours

Abstract

The CA125 assay detects circulating MUC16 and is one of the most widely used cancer biomarkers for the follow-up of ovarian cancer. We previously demonstrated that detection of aberrant cancer-associated glycoforms of MUC16 as well as MUC1 in circulation could improve the yield of these serum assays. Our aim was to refine ovarian cancer biomarkers by detection of aberrant glycoforms (Tn, STn, and T) of MUC16 and MUC1 in ovarian cancer tissue using Proximity Ligation Assays (PLA). We studied two series of serous ovarian tumours, a pilot series of 66 ovarian tumours (27 cystadenomas, 16 borderline tumours and 23 adenocarcinomas) from Centro Hospitalar S. João, Porto and a validation series of 89 ovarian tumours (17 cystadenomas, 25 borderline tumours and 47 adenocarcinomas) from the Portuguese Institute of Oncology Francisco Gentil, Lisbon. PLA reactions for MUC16/Tn, MUC16/STn, MUC1/Tn and MUC1/STn were negative in benign lesions but often positive in borderline and malignant lesions, in both series. An even better yield was obtained based on positivity for any of the four glyco-mucin profiles, further increasing sensitivity to 72% and 83% in the two series, respectively, with 100% specificity. The strategy is designated glyco-mucin profiling and provides strong support for development of PLA-based serum assays for early diagnosis.

Altered (neo-) lacto series glycolipid biosynthesis impairs α2-6 sialylation on N-glycoproteins in ovarian cancer cells

“…This technology was first demonstrated by Henrik Clausen and his colleagues, through the introduction of the ‘Simple Cell’ strategy, to study the role of truncated O -glycans in malignant diseases2324, specificity of anti-glycopeptide antibodies25, profile and map the human O -GlcNAc glycoproteome2627, and produce novel antibodies to defined glycopeptides28. Whilst a majority of this work is based on O -glycans, there is very limited information on the use of genome- editing for glycosphingolipids (GSLs) and in particular, the nsGSLs.…”

Glycosylation in cancer: mechanisms and clinical implications

“…These relative activities underlie the aberrant expression of a tumour-associated epitopes on glycoproteins, such as mucins in breast 81 and gastric 82 cancers. STn is rarely expressed in normal healthy tissues but can be detected in most carcinomas, such as those from the pancreas 83,84 , stomach 23,85,86 , colorectum 23,87 , breast 38 , bladder 88 and ovary 89 , correlating with decreased cancer cell adhesion, increased tumour growth, increased tumour cell migration, invasion and poor prognosis. The abnormal synthesis of STn in cancer occurs owing to the overexpression of ST6GalNAc-I.…”

Targeted O‐glycoproteomics explored increased sialylation and identified MUC16 as a poor prognosis biomarker in advanced‐stage bladder tumours

“…The simultaneous detection of mucin-16 (MUC16), ITGB1 and CD44 STn + -glycoforms was made by in situ proximity ligation assays (PLA) using the Duolink in situ detection reagents Brightfield and Red, respectively (Olink Bioscience, Uppsala, Sweden) according to the manufacturer's instructions and based on previous reports (Campos et al, 2015;Ricardo et al, 2015). Briefly, FFPE tissues were deparaffinized, rehydrated and subjected to acid-and heat-induced antigen retrieval, followed by incubation with 3% hydrogen peroxide and blocking solution in a humidity chamber, as previously described (Ferreira et al, 2013).…”