Lower Plasma Amyloid Beta - 42 Levels Associated With Worse Survival in Patients With Glioma

Abstract

Background/aim: Glioma is often refractory. The accumulation of amyloid beta (Aβ) in the brain is commonly associated with Alzheimer's disease (AD), but there are studies suggesting that Aβ has tumor suppressor potential. The aim of this study was to identify a novel, non-invasive candidate biomarker for histological prediction and prognostic assessment of glioma.

Patients and methods: Serum was prepared from blood samples collected preoperatively from 48 patients with WHO grade II-IV glioma between October 2004 and December 2017 at a single tertiary institution. The concentration of Aβ42 was measured using the SMCxPRO immunoassay (Merck). The clinical and histological characteristics of the patients, including molecular subtypes, were reviewed.

Results: The mean age of the patients was 52.2±12.5 years. The mean value of serum Aβ42 concentration was 7.6±7.8 pg/ml in the anaplastic astrocytoma (WHO grade III) group and 6.4±6.5 pg/ml in the glioblastoma multiforme (WHO grade IV) group. The Negative epidermal growth factor receptor (EGFR) expression was associated with higher serum Aβ42 levels (p=0.020). Kaplan-Meier analysis demonstrated that patients with high serum Aβ42 (>11.78 pg/ml) had significantly longer progression-free survival (PFS) (p=0.038) and overall survival (OS) (p=0.018).

Conclusion: This study investigated serum Aβ42 levels as a potential biomarker for glioma. The results showed that low serum Aβ42 levels were associated with EGFR expression and poor PFS and OS. Overall, these findings suggest a potential role of Aβ42 as a prognostic marker in astrocytomas.

Keywords: EGFR; Glioma; amyloid beta-peptides; astrocytoma; tumor suppressor.