Background:Phosphorylated signal transducer and activator of transcription 3(p-STAT3)has emerged as a critical modulator of hepatocellular carcinoma(HCC)progression.However,its role in three-dimensional(3D)chromatin c...Background:Phosphorylated signal transducer and activator of transcription 3(p-STAT3)has emerged as a critical modulator of hepatocellular carcinoma(HCC)progression.However,its role in three-dimensional(3D)chromatin conformation and the expression of genes linked to HCC aggressiveness remains largely unexplored.This study aimed to identify HCC 3D chromatin conformations that are regulated by sustained STAT3 activation and validate the molecular mechanisms underlying the aggressiveness of HCC.Methods:Comparative analyses were performed using HCC cell lines with varying levels of STAT3 activation.Chromatin immunoprecipitation-sequencing(ChIP-seq)for p-STAT3 and H3K27ac was conducted to map p-STAT3-associated genomic regions and assess its influence on chromatin states.Chromatin conformation sequencings(high-throughput chromosome conformation capture and high-throughput chromosome conformation capture followed by immunoprecipitation)were employed to investigate the 3D genome landscape and identify conformational changes linked to sustained p-STAT3 activation.RNAsequencing was performed to assess transcriptional changes in response to these chromatin rearrangements.Functional assays,including invasion and tube formation assays,were carried out to validate the phenotypic impact of p-STAT3 activation on HCC progressiveness.Pharmacological inhibition of STAT3 was tested to explore potential therapeutic avenues and resistance mechanisms.Results:We found that sustained activation of p-STAT3 was significantly associated with poor prognostic outcomes in HCC patients.ChIP-seq demonstrated that p-STAT3 regulated chromatin interactions,leading to the formation of frequently interacting regions(FIREs),stable structural units within the 3D genome.Genes within these p-STAT3-associated FIREs exhibited coordinated expression,with many involved in aggressiveness HCC phenotypes like invasion and tube formation.Chromatin conformation data indicated that these FIREs altered topologically associating domains(TADs),potentially influencing broader chromatin organization.Despite STAT3 inhibition,p-STAT3-associated chromatin conformations remained intact,maintaining the expression of genes within FIREs and contributing to drug resistance.Conclusions:Sustained p-STAT3 activation significantly alters the 3D chromatin conformation inHCC,particularly through the formation of FIREs.These p-STAT3-associated FIREs drive the expression of genes involved inHCC aggressiveness and remain active despite STAT3-targeted treatments,suggesting a mechanism of drug resistance.These findings highlight the potential of targeting 3D chromatin dynamics as a therapeutic strategy in HCC,especially in cases of STAT3 inhibitor resistance.展开更多
Background:Increased Galectin 3-binding protein(LGALS3BP)serum levels have been used to assess hepatic fibrosis stages and the severity of hepatocellular carcinoma(HCC).Considering the crucial role of transforming gro...Background:Increased Galectin 3-binding protein(LGALS3BP)serum levels have been used to assess hepatic fibrosis stages and the severity of hepatocellular carcinoma(HCC).Considering the crucial role of transforming growth factor-β1(TGF-β1)in the emergence of these diseases,the present study tested the hypothesis that LGALS3BP regulates the TGF-β1 signaling pathway.Methods:The expression levels of LGALS3BP and TGFB1 were analyzed in patients with metabolic dysfunction-associated steatohepatitis(MASH)and HCC.Multiple omics techniques,such as RNA-sequencing,transposaseaccessible chromatin-sequencing assay,and liquid chromatography-tandem mass spectrometry proteomics,were used to identify the regulatory mechanisms for the LGALS3BP-TGF-β1 axis.The effects of altered TGF-β1 signaling by LGALS3BP were investigated in conditional LGALS3BP-knockin and LGALS3BP-knockout mice.Results:In patients with MASH and HCC,the levels of LGALS3BP and TGFB1 exhibited positive correlations.Stimulation of LGALS3BP by the inflammatory cytokine interferonαin HCC cells or ectopic overexpression of LGALS3BP in hepatocytes promoted the expression levels of TGFB1.Aggravated fibrosis was observed in the livers of hepatocyte-specific LGALS3BP-knockin mice,with increased TGFB1 levels.LGALS3BP directly bound to and assembled integrinαV,an integral mediator required for releasing active TGF-β1 from extracellular latent complex with the rearranged F-actin cytoskeleton.The released TGF-β1 activated JunB transcription factor,which in turn promoted the TGF-β1 positive feedback loop.LGALS3BP deletion in the hepatocytes downregulated TGF-β1 signaling and CCl4 induced fibrosis.Moreover,LGALS3BP depletion hindered hepatocarcinogenesis by limiting the availability of fibrogenic TGF-β1.Conclusion:LGALS3BP plays a crucial role in hepatic fibrosis and carcinogenesis by controlling the TGF-β1 signaling pathway,making it a promising therapeutic target in TGF-β1-related diseases.展开更多
基金National Research Foundation of KoreaMinistry of Science and ICT,Korea,Grant/Award Numbers:2022M3A9B6017424,NRF-2021R1A6A1A03038890,2023R1A2C1005868,2022M3A9B6017654+2 种基金Korea Basic Science InstituteNational Research Facilities and Equipment CenterMinistry of Education of Korea,Grant/Award Number:RS-2024-00436674。
文摘Background:Phosphorylated signal transducer and activator of transcription 3(p-STAT3)has emerged as a critical modulator of hepatocellular carcinoma(HCC)progression.However,its role in three-dimensional(3D)chromatin conformation and the expression of genes linked to HCC aggressiveness remains largely unexplored.This study aimed to identify HCC 3D chromatin conformations that are regulated by sustained STAT3 activation and validate the molecular mechanisms underlying the aggressiveness of HCC.Methods:Comparative analyses were performed using HCC cell lines with varying levels of STAT3 activation.Chromatin immunoprecipitation-sequencing(ChIP-seq)for p-STAT3 and H3K27ac was conducted to map p-STAT3-associated genomic regions and assess its influence on chromatin states.Chromatin conformation sequencings(high-throughput chromosome conformation capture and high-throughput chromosome conformation capture followed by immunoprecipitation)were employed to investigate the 3D genome landscape and identify conformational changes linked to sustained p-STAT3 activation.RNAsequencing was performed to assess transcriptional changes in response to these chromatin rearrangements.Functional assays,including invasion and tube formation assays,were carried out to validate the phenotypic impact of p-STAT3 activation on HCC progressiveness.Pharmacological inhibition of STAT3 was tested to explore potential therapeutic avenues and resistance mechanisms.Results:We found that sustained activation of p-STAT3 was significantly associated with poor prognostic outcomes in HCC patients.ChIP-seq demonstrated that p-STAT3 regulated chromatin interactions,leading to the formation of frequently interacting regions(FIREs),stable structural units within the 3D genome.Genes within these p-STAT3-associated FIREs exhibited coordinated expression,with many involved in aggressiveness HCC phenotypes like invasion and tube formation.Chromatin conformation data indicated that these FIREs altered topologically associating domains(TADs),potentially influencing broader chromatin organization.Despite STAT3 inhibition,p-STAT3-associated chromatin conformations remained intact,maintaining the expression of genes within FIREs and contributing to drug resistance.Conclusions:Sustained p-STAT3 activation significantly alters the 3D chromatin conformation inHCC,particularly through the formation of FIREs.These p-STAT3-associated FIREs drive the expression of genes involved inHCC aggressiveness and remain active despite STAT3-targeted treatments,suggesting a mechanism of drug resistance.These findings highlight the potential of targeting 3D chromatin dynamics as a therapeutic strategy in HCC,especially in cases of STAT3 inhibitor resistance.
基金Bio&Medical Technology Development Program of the National Research Foundation,Grant/Award Numbers:NRF-2020M3A9G3080281,NRF-2020R1A5A2031185Korean Government。
文摘Background:Increased Galectin 3-binding protein(LGALS3BP)serum levels have been used to assess hepatic fibrosis stages and the severity of hepatocellular carcinoma(HCC).Considering the crucial role of transforming growth factor-β1(TGF-β1)in the emergence of these diseases,the present study tested the hypothesis that LGALS3BP regulates the TGF-β1 signaling pathway.Methods:The expression levels of LGALS3BP and TGFB1 were analyzed in patients with metabolic dysfunction-associated steatohepatitis(MASH)and HCC.Multiple omics techniques,such as RNA-sequencing,transposaseaccessible chromatin-sequencing assay,and liquid chromatography-tandem mass spectrometry proteomics,were used to identify the regulatory mechanisms for the LGALS3BP-TGF-β1 axis.The effects of altered TGF-β1 signaling by LGALS3BP were investigated in conditional LGALS3BP-knockin and LGALS3BP-knockout mice.Results:In patients with MASH and HCC,the levels of LGALS3BP and TGFB1 exhibited positive correlations.Stimulation of LGALS3BP by the inflammatory cytokine interferonαin HCC cells or ectopic overexpression of LGALS3BP in hepatocytes promoted the expression levels of TGFB1.Aggravated fibrosis was observed in the livers of hepatocyte-specific LGALS3BP-knockin mice,with increased TGFB1 levels.LGALS3BP directly bound to and assembled integrinαV,an integral mediator required for releasing active TGF-β1 from extracellular latent complex with the rearranged F-actin cytoskeleton.The released TGF-β1 activated JunB transcription factor,which in turn promoted the TGF-β1 positive feedback loop.LGALS3BP deletion in the hepatocytes downregulated TGF-β1 signaling and CCl4 induced fibrosis.Moreover,LGALS3BP depletion hindered hepatocarcinogenesis by limiting the availability of fibrogenic TGF-β1.Conclusion:LGALS3BP plays a crucial role in hepatic fibrosis and carcinogenesis by controlling the TGF-β1 signaling pathway,making it a promising therapeutic target in TGF-β1-related diseases.
