High-Mannose N-Glycans To Monitor Early Response to Chemotherapy in African Epithelial Ovarian Cancer Patients - A Pilot Study

Sep 29, 2026

Uploaded by McQueen

Epithelial ovarian cancer remains highly lethal, driven in large part by insufficient sensitive and specific early diagnostic biomarkers for timely intervention. N-glycosylation is altered across cancers, yet African population-specific N-glycome data are limited. This pilot study investigated aberrant N-glycosylation in an African EOC cohort, comparing primary patients and those undergoing chemotherapy. Results showed that high-mannose N-glycans rose with early treatment response, while complex-type sialylated fucosylated N-glycans declined, especially later.

LanguageEnglish

CategoryHealthcare

FormatPDF

Pages10

Reading Time25 min

AccessFree to download

Abstract

Introduction

Clinical challenge and treatment context

Limitations of existing biomarkers

Rationale for N-glycans and MALDI-TOF-MS

Keywords

This article is licensed under CC-BY 4.0 [pubs.acs.org/jpr](pubs.acs.org/jpr) Article High-Mannose N‑Glycans To Monitor Early Response to Chemotherapy in African Epithelial Ovarian Cancer Patients􀀁A Pilot Study Published as part of Journal of Proteome Research special issue “Multiomics in Africa and the Middle East”. Francis M. Wanyama, * Obinna Umeh, Karina Biskup, Rudolf Tauber, Alfred Mokomba, Catherine Nyongesa, and Véronique Blanchard * Cite This: J. Proteome Res. 2026, 25, 99−108 Read Online | | | | | | | | --- | --- | --- | --- | --- | --- | | ACCESS | Metrics & More | | Article Recommendations | | *sı Supporting Information | ABSTRACT: Epithelial ovarian cancer (EOC) remains the most lethal form of cancer despite improvements in surgical techniques and therapeutic interventions over recent decades. The high mortality rate is largely associated with a lack of sensitive and specific early diagnostic biomarkers to allow timely intervention. Hence, the identification and validation of novel noninvasive biomarkers for primary diagnosis and for disease monitoring is of high importance. Malignant transformations of N-glycosylation have been reported across various cancer types including EOC, but little is known about the N-glycome of African populations. In this work, we investigated aberrant N-glycosylation for the first time in an African EOC cohort comprising primary patients and those undergoing chemotherapy. In this pilot study, the N-glycome of African EOC and controls was comparable to those previously found in European cohorts. Of importance, high-mannose Nglycans increased with response to treatment in early chemotherapy cycles, and complex-type sialylated fucosylated N-glycans decreased, especially in the late chemotherapy cycles. Interestingly, the glycan-based index that we previously developed to detect primary EOC was more sensitive and specific than the routine diagnostic biomarker to identify primary EOC and to monitor chemoresponse in the early phase of the treatment. KEYWORDS: N-glycans, ovarian cancer, chemotherapy response, cancer biomarkers, benign ovarian disease, African ethnicity, permethylation, MALDI-TOF mass spectrometry ■ INTRODUCTION Although surgical techniques and therapies have improved over the past decades, ovarian cancer (OC) remains the most lethal malignancy among gynecological cancers.1 The high death rates due to OC arise from its propensity tomisdiagnosis, as its symptoms are unspecific in the early stage (FIGO stage I and II) and lack accurate early diagnostic biomarkers. A majority of patients are diagnosed in late-stage (FIGO stages III and IV) of OC when cancer has already metastasized and treatment options have greatly diminished. Furthermore, resistance to chemotherapy and the presence of malignant ascites among epithelial OC patients have also been associated with poor prognosis and early death.2,3 In both developed and underdeveloped countries, more than 75% of OC patients are regrettably diagnosed in the third and fourth stages.2,3 Surgical debulking followed by chemotherapy remains the current standard front-line treatment for OC.2,3 A combination of platinum and paclitaxel is the standard firstline chemotherapy treatment approach usually administered in cycles of 3 weeks or carboplatin every 3 weeks and paclitaxel weekly, for six cycles. Unfortunately, patients may experience intrinsic or acquired resistance to chemotherapy. The most prominent mechanisms of platinum resistance include reduced drug uptake and increased efflux, enhanced DNA adduct repair, and increased drug inactivation by glutathione.4,5 Despite the availability of new treatment approaches, such as immunotherapy, resistance to chemotherapy continues to significantly impact the survival of OC patients. Indeed, despite their success in treating several tumor types including melanoma and lung cancer, the novel therapies arresting immune checkpoint pathways are not recommended

FAQs

Why are early diagnostic biomarkers important in epithelial ovarian cancer?

Epithelial ovarian cancer often presents with nonspecific early symptoms and is frequently diagnosed at late stages. Limited sensitive and specific biomarkers delay timely intervention and worsen outcomes.

What N-glycan changes were observed with chemotherapy response?

High-mannose N-glycans increased with response during early chemotherapy cycles. Complex-type sialylated fucosylated N-glycans decreased, especially in late chemotherapy cycles.

How did the glycan-based index compare with the routine biomarker CA125?

The previously developed glycan-based index for primary EOC was reported to be more sensitive and specific than routine biomarker CA125 for identifying primary disease and monitoring chemoresponse in the early phase.

Sep 29, 2026

Uploaded by McQueen