Circ_0000052/miR‐382‐3p axis induces PD‐L1 expression and regulates cell proliferation and immune evasion in head and neck squamous cell carcinoma

Abstract

Head and neck squamous cell carcinoma (HNSCC), which includes tumours of the lip, oral cavity, larynx, oropharynx and hypopharynx, accounted for 3.9% of new cases and 3.7% of cancer deaths in 2020. In the Asia region, it has been observed to have the highest incidence. 1 Despite multimodal treatment, including surgery and radiotherapy, with or without conventional chemotherapy, around 30%-40% of patients with aggressive disease develop distant metastases within 5 years. 2 Checkpoint blockade immunotherapy has achieved significant efficacy in improving clinical outcomes by increasing antitumor immune responses. 3 However, only a small

YTHDF2-mediated circYAP1 drives immune escape and cancer progression through activating YAP1/TCF4-PD-L1 axis

“…Circ_0000052 targeted miR-382-3p and attenuated its inhibition of PD-L1 in head and neck squamous cell carcinoma. 36 In the hypoxic microenvironment of hepatocellular carcinoma, circPRDM4 recruited HIF-1α to the PD-L1 promoter region and promoted PD-L1 upregulation. 37 Similarly, we found that circYAP1 increased PD-L1 expression by promoting its transcription in CRC.…”

MicroRNAs as regulators of immune checkpoints in cancer immunotherapy: targeting PD-1/PD-L1 and CTLA-4 pathways

“…The study not only confirms that the IFN-γ/JAK2/STAT1 signaling pathway can induce PD-L1 overexpression in HNSCC but also uncovers a novel mechanism by which the upregulated circ_0000052 mediates PD-L1 overexpression. Specifically, circ_0000052 competes with miR-382-3p for binding and alleviates its inhibitory effect on PD-L1 expression ( 156 ).…”

Exploring the evolving roles and clinical significance of circRNAs in head and neck squamous cell carcinoma

“…Its interaction with the ligand PD-L1 (programmed death-ligand 1) on cancer cells prevents the activation of tumor antigen-specific T cells, contributing to the immune evasion of cancer cells 100 , 101 . circ_0000052 upregulates PD-L1 expression by sequestering miR-382-3p, thereby promoting the malignant progression of HNSCC 77 . Ge et al demonstrated that EBV-encoded circBART2.2 expression promotes PD-L1 transcription through the binding of circBART2.2 to the helicase domain of RIG-I and the activation of transcription factors IRF3 and NF-κB, resulting in immune evasion of NPC 102 .…”