| Expression pattern: |
UP |
| Associated gene: |
HIF-1alpha, CD274 promoter |
| Associated microRNA: |
- |
| Biological function: |
promotes immune escape and inhibits CD8+ T cell-mediated anti-tumor immunity under hypoxic conditions by inducing PD-L1 expression |
| Molecular mechanism: |
circPRDM4 acts as a scaffold recruiting HIF-1alpha to the CD274 (PD-L1) promoter to enhance HIF-1alpha-mediated transactivation of PD-L1 |
| Biological pathway or process: |
immune regulation (inhibits); other pathway/process (promotes) |
| Detected method: |
Q
S
|
| Validation methods: |
circRNA-seq; RT-qPCR; RNase R Treatment; divergent primers PCR; Sanger Sequencing; Actinomycin D / DRB Stability Assay; FISH / smFISH; Nuclear-Cytoplasmic Fractionation; Clinical Sample Validation; Western Blot; Flow Cytometry（Non-apoptosis/cycle）; ELISA; RNA Pull-Down; RIP (RNA Immunoprecipitation); ChIP / ChIP-seq; Luciferase Reporter Assay; In Vivo Animal Model; H&E Staining; Transfection; Cohort Study; Survival Analysis; Bioinformatics Analysis |
| Clinical significance: |
circPRDM4 was upregulated in responders to PD-1 blockade and associated with therapeutic efficacy; high circPRDM4 expression was associated with prolonged PFS and OS |
| Description: |
In HCC under hypoxia, circPRDM4 promotes immune escape by increasing PD-L1 (CD274) transcription and reducing CD8+ T cell infiltration/cytotoxicity. Mechanistically, it functions in the nucleus as a scaffold that recruits HIF-1alpha to the CD274 promoter to enhance HIF-1alpha-mediated transactivation. Clinically, higher circPRDM4 is enriched in PD-1 blockade responders and associates with longer PFS/OS. |
| Confidence score: |
0.8966 |