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Background & Aims\ud Metabolic syndrome can lead to the clinical manifestation of non-alcoholic fatty liver disease (NAFLD) and hepatocellular carcinoma (HCC) as part of the natural history of NAFLD. Despite a strong causative link, NAFLD-HCC is often underrepresented in systematic genome explorations.\ud Methods\ud Here, tumor-normal pairs from 100 subjects diagnosed with NAFLD-HCC were subject to next generation sequencings. Bioinformatic analyses were performed to identify key genomic, epigenomic and transcriptomic events associated with the pathogenesis of NAFLD to NAFLD-HCC. Establishment of primary patient-derived NAFLD-HCC culture was used as a representative human model for downstream in vitro investigations of underlying CTNNB1 S45P driver mutation. Syngeneic immunocompetent mouse model was used to further test the involvement of CTNNB1mut and TNFRSF19 in reshaping the tumor microenvironment.\ud Results\ud Mutational process operative in NAFLD-liver inferred susceptibility to tumor formation through defective DNA repair pathways. Dense promoter mutations and dysregulated transcription factors accentuated activated transcriptional regulation in NAFLD-HCC, in particular the enrichment of MAZ-MYC activities. Somatic events common in HCCs arising from NAFLD and viral hepatitis B infection underscore similar driver pathways, although an incidence shift highlights CTNNB1mut dominance in NAFLD-HCC (33%). Immune exclusion correlated evidently with CTNNB1mut. ChIP-seq integrated with transcriptome and immune profiling showed for the first time a transcriptional axis of CTNNB1mut/TNFRSF19/repressed senescence-associated secretory phenotype-like (SASP-like) cytokines (including IL6 and CXCL8). This phenomenon could be reverted by Wnt-modulator ICG001.\ud Conclusions\ud The unique mutational processes in NAFLD-liver and NAFLD-HCC alludes to a “field effect”. Whereby, distinct aberrations and shift in driver events reveal a gain-of-function role of CTNNB1 mutations in immune exclusion via TNFRSF19 inhibition of SASP-like features.\ud LAY SUMMARY\ud The increasing prevalence of metabolic syndrome in adult populations poised NAFLD-induced HCC to be the major type of liver cancer of the 21st century. We showed a strong “field effect” in NAFLD-liver from mutational signatures detected and a mechanistic path of activated β-catenin in reshaping the tumor-immune microenvironment.

Zinc finger protein X-linked (ZFX) is a zinc finger protein of Zfy family, which is highly conserved in vertebrates. This transcriptional regulator is not only highly expressed in embryonic stem cells (ESC) and hematopoietic stem cells, but is also upregulated in a number of human cancers where it is functional related to cell proliferation and survival. Hepatocellular carcinoma (HCC) is highly aggressive cancer that commonly resistant to most chemotherapies and displays stemness characteristics. In this study, we examined the expression of ZFX in HCC and its possible functional implications in liver tumorigenesis. Quantitative RT-PCR analysis showed common overexpressions of ZFX in 51.8% HCC tumors when compared with their adjacent nonmalignant liver (n = 43/83; p = 0.004). Inline with the pluripotency role of ZFX, we found silencing of ZFX readily inhibited self-renewal capability (p = 0.0022), colony formation ability (p < 0.0001) and cell proliferation (p < 0.0001) through G0/G1 cell cycle arrest of HCC cells (p = 0.0038). In addition, suppression of ZFX sensitized HCC cells to chemotherapeutic agent cisplatin (p < 0.0001). Further investigations suggested that ZFX bind on the promoter of two important mediators, namely Nanog and SOX-2, activating their expressions in HCC (p < 0.0001). Moreover, in vivo xenograft study demonstrated that overexpression of ZFX would promote the tumor growth (p = 0.031). Taken together, our results show, for the first time, commonly overexpressions of ZFX in HCC, where it likely contributes to the stemness and pluripotent behavior of this highly malignant cancer.

Zinc finger protein X-linked (ZFX) is a zinc finger protein of Zfy family, which is highly conserved in vertebrates. This transcriptional regulator is not only highly expressed in embryonic stem cells (ESC) and hematopoietic stem cells, but is also upregulated in a number of human cancers where it is functional related to cell proliferation and survival. Hepatocellular carcinoma (HCC) is highly aggressive cancer that commonly resistant to most chemotherapies and displays stemness characteristics. In this study, we examined the expression of ZFX in HCC and its possible functional implications in liver tumorigenesis. Quantitative RT-PCR analysis showed common overexpressions of ZFX in 51.8% HCC tumors when compared with their adjacent nonmalignant liver (n = 43/83; p = 0.004). Inline with the pluripotency role of ZFX, we found silencing of ZFX readily inhibited self-renewal capability (p = 0.0022), colony formation ability (p0.0001) and cell proliferation (p0.0001) through G0/G1 cell cycle arrest of HCC cells (p = 0.0038). In addition, suppression of ZFX sensitized HCC cells to chemotherapeutic agent cisplatin (p0.0001). Further investigations suggested that ZFX bind on the promoter of two important mediators, namely Nanog and SOX-2, activating their expressions in HCC (p0.0001). Moreover, in vivo xenograft study demonstrated that overexpression of ZFX would promote the tumor growth (p = 0.031). Taken together, our results show, for the first time, commonly overexpressions of ZFX in HCC, where it likely contributes to the stemness and pluripotent behavior of this highly malignant cancer.