circRNA basic information
circBase ID: hsa_circ_0001573
Name: hsa_circ_RREB1
Synonym: circRNA-BISC / BISC
Host Gene: RREB1
Genomic location(hg19): chr6:7176887-7189555:+
Genomic location(hg38): chr6:7176654-7189322:+
Subcellular localization: nucleus and cytoplasm
 
 
 
 
 
 
 
Disease basic information
MONDO ID:
0005494
MONDO name: triple-negative breast carcinoma
Disease details: triple-negative breast cancer / TNBC
Disease DO ID:
0060081
Disease MeSH ID:
D064726
Disease NCIt ID:
C71732
Disease ICD11 ID:
-
Disease OMIM ID:
-
Species: Human
Species details: Homo sapiens
Tissue specimen:

tumor tissues

Cell lines:

MDA-MB-231; BT549; MDA-MB-231/Res; BT549/Res

In vivo animal model:

cell line-derived xenograft

circRNA-disease information
Expression pattern:
DN
Associated gene: IGF2BP2, c-myc mRNA, c-MYC
Associated microRNA: -
Biological function: sensitizes BETi-resistant TNBC to BET inhibitors; inhibits c-MYC translation; represses acquired BETi resistance; enhances BETi therapeutic response and tumor regression when combined with OTX015
Molecular mechanism: BISC binds IGF2BP2 and competitively inhibits recruitment of c-myc mRNA to IGF2BP2, thereby suppressing IGF2BP2-mediated c-MYC translation; interaction depends on “CAC-|9-12|-XGGX” motifs
Biological pathway or process:

drug resistance (inhibits); proliferation (inhibits); apoptosis (other)

Detected method:
Q
Validation methods:

RIP (RNA Immunoprecipitation); RNA-seq; RT-qPCR; RNase R Treatment; Back-Splice Junction PCR / divergent primers PCR; Sanger Sequencing; FISH / smFISH; Nuclear-Cytoplasmic Fractionation; RNA Pull-Down; Western Blot; Luciferase Reporter Assay; Transfection; CCK8; Colony Formation Assay; In Vivo Animal Model; Bioinformatics Analysis

Clinical significance:

-

Description:

BISC (hsa_circ_0001573), derived from RREB1, is down-regulated in BETi-resistant TNBC cells. It directly binds the RBP IGF2BP2 (via “CAC-|9-12|-XGGX” motifs) and antagonizes IGF2BP2 recruitment to c-myc mRNA, suppressing c-MYC translation and restoring sensitivity to BET inhibitors; in vivo delivery of circularized BISC plus OTX015 causes tumor regression in resistant xenografts.

Confidence score:

0.8118

Other information
Title:

A circular RNA overcomes acquired resistance to BET inhibitors by antagonizing IGF2BP2-mediated c-MYC translation in TNBC.

Journal: Proceedings of the National Academy of Sciences of the United States of America
Published: 2025
PubMed ID: 40591591
Study type:

combined biological and clinical study

Data availability: GSE290133
Code availability: -