Introduction

Serum biomarker monitoring is essential for management of germ-cell tumors(GCT). However, not all GCT are positive for conventional tumor markers. We examined whether serum N-glycan-based biomarkers can be applied for detection and prognosis in patients with GCT._x000D_

Methods

We performed a comprehensive N-glycan structural analysis of sera from 54 untreated GCT patients and 103 age-adjusted healthy volunteers using glycoblotting methods and mass spectrometry. Candidate N-glycans were selected from those with the highest association; cutoff concentration values were established, and an N-glycan score was created based on the number of positive N-glycans present. The validity of this score for diagnosis and prognosis was analyzed using a receiver operating characteristic (ROC) curve._x000D_

Results

We identified 5 candidate N-glycans significantly associated with GCT_x000D_ patients (A). The accuracy of the N-glycan score for GCT was significant with an area-under-the-curve (AUC) value of 0.87 (B). Diagnostically, the N-glycan score detected 10 of 12 (83%) patients with negative conventional tumor markers (C). _x000D_ Prognostically, the N-glycan score was comprised 4 candidate N-glycans (D). The predictive value of the prognostic N-glycan score was significant, with an AUC value of 0.89 (E). A high value prognostic N-glycan score was significantly associated with poor prognosis (F)._x000D_ Finally, to identify a potential carrier protein, immunoglobulin (Ig) fractions of sera were subjected to N-glycan analysis and compared to whole sera. Candidate N-glycans in Ig-fractions were significantly decreased; therefore, the carrier protein for candidate N-glycans is likely not an immunoglobulin.

Conclusions

Our newly developed N-glycan score seems to be a practical diagnostic and prognostic method for GCT.

Funding

None