The 3' Non-Coding Sequence Negatively Regulates PD-L1 Expression, and Its Regulators Are Systematically Identified in...

Area of Science:

• Molecular Biology
• Cancer Research
• Immunology

Background:

• The 3 -untranslated region (3 -UTR) of PD-L1 is largely unstudied despite its length.
• Understanding PD-L1 regulation is crucial for cancer immunotherapy.

Purpose of the Study:

• To investigate the role of the PD-L1 3 -UTR in regulating PD-L1 expression.
• To identify novel regulators of PD-L1 and their potential as biomarkers for immunotherapy response.

Main Methods:

• CRISPR-Cas9 gene editing to delete the PD-L1 3 -UTR.
• Bioinformatic analyses including prognostic, immune infiltration, and microRNA network analysis.
• Correlation analysis of RNA-binding proteins (RBPs), microRNAs, and m6A regulators with PD-L1 expression.

Main Results:

• Deletion of the PD-L1 3 -UTR significantly up-regulated PD-L1 expression.
• Identified 43 RBPs, 38 microRNAs, and 21 m6A regulators associated with PD-L1.
• Developed a novel immune signature (RBMS1, QKI, ZC3HAV1, RBM38) for predicting immunotherapy response.

Conclusions:

• The PD-L1 3 -UTR plays a critical role in PD-L1 regulation.
• The identified regulators and the developed signature show potential as biomarkers for cancer prognosis and predicting immunotherapy efficacy.