Mechanisms of tumor heterogeneity in TACE-resistant liver cancer: Insights from single-cell and whole-exome sequencing.

BACKGROUND: HCC is a significant health concern. CTNNB1 mutations are implicated in HCC progression and resistance to transarterial chemoembolization (TACE), potentially through the ITGB1/PI3K/AKT pathway. METHODS: HCC was induced in mice using diethylnitrosamine, and TACE-resistant models were established. Tumor tissue analysis, single-cell and whole-exome sequencing identified gene mutations and cellular interactions. CRISPR/Cas9 was used to generate HCC cells with CTNNB1 mutations, and functional assays evaluated their proliferation, migration, and invasion. Cocultivation with HUVEC cells and animal models assessed angiogenesis and tumorigenesis. RESULTS: The study successfully established a TACE-resistant mouse model, identifying mesenchymal cell alterations and enhanced cellular communication in resistant mice. Signaling pathways like SPP1 were implicated in epithelial-mesenchymal transition. Analysis revealed a CTNNB1 (c.890T>C) mutation in TACE-resistant patients, with subsequent experiments confirming enhanced proliferation, migration, and epithelial-mesenchymal transition in CTNNB1 mutant HCC cells. Cocultivation studies with HUVEC cells indicated a pro-angiogenic effect of CTNNB1 mutant HCC cells, mediated by the ITGB1 pathway. Animal experiments demonstrated tumorigenic properties of CTNNB1 mutant cells, further validated by histopathological and immunohistochemical analyses. CONCLUSIONS: CTNNB1 mutations elevate ITGB1, activate PI3K/AKT, induce epithelial-mesenchymal transition, enhancing proliferation, migration, and angiogenesis, contributing to TACE resistance, suggesting novel therapeutic targets in HCC through signaling pathway interventions.