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Journal of Neuro-Oncology

, Volume 136, Issue 3, pp 453–461 | Cite as

Prognostic relevance of programmed cell death ligand 1 expression in glioblastoma

  • Kyu Sang Lee
  • Kyoungyul Lee
  • Sumi Yun
  • Seyoung Moon
  • Yujun Park
  • Jung Ho Han
  • Chae-Yong Kim
  • Hye Seung Lee
  • Gheeyoung ChoeEmail author
Laboratory Investigation

Abstract

The aim of this study was to determine the clinicopathological significance of programmed cell death ligand 1 (PD-L1) expression in glioblastoma (GBM). In a retrospective cohort of 115 consecutive patients with GBM, PD-L1 expression was determined using immunohistochemistry (IHC). Membranous and fibrillary PD-L1 staining of any intensity in > 5% neoplastic cells and tumour infiltrating immune cells (TIIs) was considered positive staining. In addition, isocitrate dehydrogenase-1 (IDH-1) (R132H) expression and cluster of differentiation 3 (CD3)-positive T-cell infiltration were investigated using IHC. O(6)-methylguanine-DNA methyltransferase (MGMT) promoter methylation assay and fluorescence in situ hybridization (FISH) for the assessment of 1p/19q deletion were performed. Expression of PD-L1 in tumour cells and TIIs was found in 37 (32.2%) and 6 (5.2%) patients, respectively. Kaplan–Meier analysis indicated that PD-L1 expression in tumour cells was significantly associated with poor overall survival (OS) (P = 0.017), though multivariate Cox analysis did not confirm this association (hazard ratio 1.204; P = 0.615). PD-L1 expression in TIIs did not correlate with the patient prognosis (P = 0.545). In addition, MGMT methylation and IDH-1 (R132H) expression were associated with a better prognosis (P < 0.001 and P = 0.024, respectively). The expression of PD-L1 was associated with CD3-positive T-cell infiltration (P < 0.001), and IDH-1 wild type status (P = 0.008). A deeper insight into PD-L1 expression could help to ensure the success of future immunotherapy in GBM. Our study suggested that PD-L1 target therapy might be beneficial for PD-L1-expressing GBM patients with a poor prognosis.

Keywords

Glioblastoma Programmed cell death ligand 1 CD274 Immunohistochemistry Prognosis 

Notes

Funding

This research was funded by the Seoul National University Bundang Hospital research fund (Grant Number: 11-2011-021).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

All procedures performed in this study involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. The Institutional Review Board of Seoul National University Bundang Hospital approved the use of medical record data and tissue samples for this study (Reference: B-1612/374-304).

Informed consent

For this type of study, formal consent is not required.

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Authors and Affiliations

  1. 1.Department of PathologySeoul National University Bundang HospitalSeongnam-siRepublic of Korea
  2. 2.Department of PathologyKangwon National University HospitalChuncheon-SiRepublic of Korea
  3. 3.Department of Diagnostic PathologySamkwang Medical LaboratoriesSeoulRepublic of Korea
  4. 4.Department of NeurosurgerySeoul National University Bundang HospitalSeongnam-siRepublic of Korea

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