TCF3 activates super-enhancer-driven TRIB2 overexpression to suppress ferroptosis and promote hepatoblastoma proliferation.

BACKGROUND: Hepatoblastoma (HB) is the most common pediatric liver malignancy with an increasing incidence. However, the functional roles of 3D chromatin organization, epigenetic regulatory factors, and transcriptional reprogramming in HB pathogenesis remain poorly understood. METHODS: ​Integrated multi-omics analyses of HB and matched non-tumor tissues were performed, including Hi-C, H3K27ac CUT&Tag, ATAC-seq, and RNA-seq, to construct high-resolution 3D epigenomic maps and identify genes interacting with HB-specific super-enhancers (SEs). Functional assays of identified targets were conducted in cell lines and animal models. The regulatory mechanisms of SEs and upstream transcription factors (TFs) were investigated using CRISPRi-dCas9, 3C-qPCR, ChIP-qPCR, and luciferase reporter assays. RESULTS: Comprehensive analysis identified TRIB2 as an HB-specific SE-associated oncogene. Functionally, TRIB2 promoted cell proliferation and accelerated tumor growth both in vitro and in vivo. Patients with high TRIB2 expression exhibited advanced PRETEXT stage and metastasis. Mechanistically, TCF3 directly bound to both the TRIB2-SE and its promoter, promoting TRIB2 overexpression. Moreover, TRIB2 conferred resistance to ferroptosis by disrupting KEAP1-mediated ubiquitination of NRF2, thereby stabilizing NRF2 protein and enhancing antioxidant responses. The TCF3-TRIB2-NRF2 axis showed significant co-expression in HB tissues, effectively distinguished HB from normal liver tissues, and was associated with poorer overall survival. CONCLUSIONS: Our findings reveal that TCF3 and SE mediate TRIB2 overexpression to inhibit ferroptosis via the KEAP1-NRF2 pathway and drive HB pathogenesis, providing potential diagnostic and prognostic markers for HB.