| Expression pattern: |
UP |
| Associated gene: |
LIG1, FOXA1, TET1, QKI |
| Associated microRNA: |
- |
| Biological function: |
Promotes gemcitabine resistance, promotes proliferation, inhibits apoptosis, and decreases gemcitabine-induced DNA damage in PDAC cells. |
| Molecular mechanism: |
hsa_circ_0007919 binds/recruits FOXA1 and TET1 to the LIG1 promoter, decreases promoter methylation, increases LIG1 transcription, and activates multiple DNA repair pathways; GEM enhances QKI-mediated back-splicing to increase hsa_circ_0007919 biogenesis. |
| Biological pathway or process: |
base excision repair (promotes); mismatch repair (promotes); nucleotide excision repair (promotes); apoptosis (inhibits); proliferation (promotes); drug resistance (promotes) |
| Detected method: |
Q
S
|
| Validation methods: |
RNA-seq; RT-qPCR; Back-Splice Junction PCR / divergent primers PCR; Sanger Sequencing; RNase R Treatment; FISH / smFISH; Nuclear-Cytoplasmic Fractionation; Clinical Sample Validation; Transfection; CCK8; Annexin V/PI Flow Cytometry; IF (Immunofluorescence); In Vivo Animal Model; IHC (Immunohistochemistry); TUNEL; RIP (RNA Immunoprecipitation); Co-IP; ChIP / ChIP-seq; Luciferase Reporter Assay; MSP (Methylation-Specific PCR); Bioinformatics Analysis |
| Clinical significance: |
High expression of hsa_circ_0007919 predicts poor OS and DFS in PDAC patients (including GEM-resistant/GEM-treated subsets). |
| Description: |
In gemcitabine-resistant PDAC, hsa_circ_0007919 is upregulated and promotes chemoresistance by reducing gemcitabine-induced DNA damage and apoptosis. It localizes mainly in the nucleus and enhances LIG1 transcription by recruiting FOXA1 and TET1 to the LIG1 promoter to reduce promoter methylation, thereby activating multiple DNA repair pathways. |
| Confidence score: |
0.8831 |