Prognostic value of programmed death ligand 1 (PD-L1) in glioblastoma: a systematic review, meta-analysis and validation based on dataset

ABSTRACT

Excellent prognostic value of programmed death ligand 1 (PD-L1) is observed in patients with other cancers; however, the prognostic value of PD-L1 in glioblastoma (GBM) remains unclear. Therefore, this meta-analysis evaluated the prognostic value of PD-L1 in GBM. We performed a systematic search in databases to screen eligible articles. The hazard ratio (HR) and 95% confidence interval (95% CI) were extracted from included articles. This meta-analysis included 15 studies, and the forest plot indicated that increased PD-L1 expression was associated with poorer overall survival (OS) of GBM (HR, 1.16; 95% CI, 1.05–1.27; P = 0.002). Furthermore, stratified analysis confirmed that PD-L1 expression was associated with unfavorable OS at the protein level (HR, 1.30; 95% CI, 1.13–1.48; P< 0.001) and messenger ribonucleic acid (mRNA) level (HR, 1.05; 95% CI, 1.00–1.09; P= 0.041). The analysis of a dataset verified the prognostic value of PD-L1 and revealed an association between PD-L1 mRNA expression and the status of isocitrate dehydrogenase (IDH). In conclusion, increased PD-L1 expression predicts unfavorable OS in GBM and may be a promising prognostic biomarker of GBM.

KEYWORDS:

• Glioblastoma
• immunotherapy
• isocitrate dehydrogenase
• prognostic value
• programmed death ligand 1

Highlights

• Increased PD-L1 protein expression correlates with an adverse OS of GBM.

• Increased PD-L1 mRNA expression correlates with a poor OS of GBM.

• PD-L1 mRNA expression is higher in IDH-wildtype GBM than in IDH-mutant GBM.

Acknowledgements

The authors thank all the members of the Neurosurgery Department of First Hospital of Shanxi Medical University, who provided advice in several aspects, including software, literature quality evaluation, data extraction, data curation and constructive discussions. Without their advice and support, we may have been unable to finish this study. Furthermore, thanks to Ding-Xiang-Yuan (http://www.dxy.cn), a professional communication platform for healthcare professionals. This non-profit platform helped us immensely in our work and guided us to master the knowledge of evidence-based medicine.

Availability of data and materials

All data are provided in the manuscript and can be obtained from the corresponding author.

Author contributions

Huan Wang, Youchao Xiao, and Xingguang Ren: conception of the study, formal analysis, manuscript preparation and writing; Dahai Wan: academic instruction, funding acquisition, manuscript reviewing and editing.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Supplementary material

Supplemental data for this article can be accessed here.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.