Skip to main content
. 2021 Jan 1;41(1):62–78. doi: 10.1002/cac2.12117

FIGURE 5.

FIGURE 5

miR‐675‐5p‐enhanced PD‐L1 mRNA stability is crucial for the EGFR‐P38 MAPK axis‐induced PD‐L1 accumulation. (A) SMMC‐7721 and HepG2 cells were pre‐stimulated with or without EGF for 24 h and further treated with actinomycin D (5 μg/mL) for 0‐120 min, next cellular PD‐L1 mRNA expression was detected by qRT‐PCR. (B) Cells were pre‐treated with SB203580 (10 μmol/L) or dimethylsulfoxide (DMSO) for 6 h, and then co‐stimulated with or without EGF for an additional 24 h, next cells were further treated with actinomycin D (5 μg/mL) for 0‐120 min, and cellular PD‐L1 mRNA expression was detected by qRT‐PCR. (C) Cells were stimulated with or without EGF (20 ng/mL) for 24 h, and then the expression of miR‐675‐5p was detected by qRT‐PCR. (D) Cells pre‐treated with SB203580 (10 μmol/L) or DMSO for 6 h were further co‐treated with or without EGF (20 ng/mL) for an additional 24 h, and then, the expression of miR‐675‐5p was detected by qRT‐PCR. (E) Cells were pre‐treated with mimics of miR‐675‐5p or control mimics for 24 h, and then co‐stimulated with or without EGF for an additional 24 h. Next, the cells were treated with actinomycin D (5 μg/mL) for additional indicated time periods (0‐120 min), and the cellular PD‐L1 mRNA expression was detected by qRT‐PCR. (F) Cells were pre‐transfected with mimics of miR‐675‐5p or control mimics for 24 h, and then further co‐stimulated with or without EGF (20 ng/mL) for an additional 24 h.Next, the expression of PD‐L1 was detected by qRT‐PCR and flow cytometry. * P ≤ 0.05, ** P ≤ 0.01, *** P ≤ 0.001. Abbreviations: EGFR, epidermal growth factor receptor; EGF, epidermal growth factor; PD‐L1, programmed death‐ligand 1; HLA‐ABC, human leukocyte antigen class‐A, B, C; MAPK, mitogen‐activated protein kinase.