The Clinical Significance of Deglycosylated PD-L1 Level Detection Using 28-8 Monoclonal Antibody in Lung Adenocarcinoma

Purpose: The aim of this study was to explore the clinical significance of deglycosylated PD-L1 level and its correlation with EGFR and ALK mutation in lung adenocarcinoma.Materials and Methods: We estimated the intensity of both native and deglycosylated PD-L1 signals using a 28-8 antibody on lung adenocarcinoma tissue microarray sections. We analyzed the difference in the H-score between tumor and paratumor tissues, as well as that before and after deglycosylation. Correlations between EGFR or ALK status and PD-L1 expression were analyzed. We also evaluated the differences among survival curves.Results: The expression level of PD-L1 in lung adenocarcinoma tissues was significantly higher than that in paratumor tissues (P<0.0001). Deglycosylation significantly enhanced the detection of PD-L1 in tumor tissues (P<0.0001). There was no statistical significance between the signal intensity of deglycosylated PD-L1 and the survival of patients (P=0.9099). However, the response to deglycosylation of PD-L1 was significantly correlated with the survival of patients with stage N1-N3 (P=0.0435) and stage T3-T4 (P=0.0366) and male patients (P=0.0258). A statistical trend was found in the correlation between the response to deglycosylation of PD-L1 and the survival of patients with grade II-III plus grade III (P=0.0973). Correlation between EGFR or ALK status and the expression of PD-L1 was not found (P>0.05).Conclusion: PD-L1 deglycosylation enhances the detection of PD-L1 when utilizing a 28-8 antibody. Moreover, the response to deglycosylation of PD-L1 may predict the survival of certain patients with lung adenocarcinoma.