FIGURE 2.

Upregulation of programmed cell death‐ligand 1 (PD‐L1) is associated with areca nut chewing habits and is correlated with fat mass and obesity‐associated protein (FTO) expression. (A–B) The protein (A) and mRNA (B) levels of PD‐L1 in NHOK, SCC9, CAL27, SCC25, and HSC2 cells were detected by western blotting and RT‐qPCR assay, respectively. (C) The expression levels of PD‐L1 in normal tissues (n = 44) and head and neck squamous cell carcinoma (HNSCC) tissues (n = 519) were compared and presented. (D) The expression levels of PD‐L1 in normal oral tissues (n = 18), oral squamous cell carcinoma (OSCC) without areca nut (n = 30), and oral squamous cell carcinoma (OSCC) with areca nut (n = 28) were determined by RT‐qPCR assay. (E) Representative of western blotting images showing expression of PD‐L1 and β‐actin in normal oral tissues (N), OSCC without areca nut (T), and OSCC with areca nut (T‐A). Sample IDs are shown (D and E). (F) The association between PD‐L1 expression and clinical parameters in 58 OSCC patients. (G) The correlation of FTO and PD‐L1 in 58 OSCC patients were analyzed by Pearson correlation analysis. *P < 0.05