Background Liver ischemia/reperfusion(I/R)injury is usually caused by hepatic inflow occlusion during liver surgery,and is frequently observed during war wounds and trauma.Hepatocyte ferroptosis plays a critical role ...Background Liver ischemia/reperfusion(I/R)injury is usually caused by hepatic inflow occlusion during liver surgery,and is frequently observed during war wounds and trauma.Hepatocyte ferroptosis plays a critical role in liver I/R injury,however,it remains unclear whether this process is controlled or regulated by members of the DEAD/DExH-box helicase(DDX/DHX)family.Methods The expression of DDX/DHX family members during liver I/R injury was screened using transcriptome analysis.Hepatocyte-specific Dhx58 knockout mice were constructed,and a partial liver I/R operation was performed.Single-cell RNA sequencing(scRNA-seq)in the liver post I/R suggested enhanced ferroptosis by Dhx58hep−/−.The mRNAs and proteins associated with DExH-box helicase 58(DHX58)were screened using RNA immunoprecipitation-sequencing(RIP-seq)and IP-mass spectrometry(IP-MS).Results Excessive production of reactive oxygen species(ROS)decreased the expression of the IFN-stimulated gene Dhx58 in hepatocytes and promoted hepatic ferroptosis,while treatment using IFN-αincreased DHX58 expression and prevented ferroptosis during liver I/R injury.Mechanistically,DHX58 with RNA-binding activity constitutively associates with the mRNA of glutathione peroxidase 4(GPX4),a central ferroptosis suppressor,and recruits the m6A reader YT521-B homology domain containing 2(YTHDC2)to promote the translation of Gpx4 mRNA in an m6A-dependent manner,thus enhancing GPX4 protein levels and preventing hepatic ferroptosis.Conclusions This study provides mechanistic evidence that IFN-αstimulates DHX58 to promote the translation of m6A-modified Gpx4 mRNA,suggesting the potential clinical application of IFN-αin the prevention of hepatic ferroptosis during liver I/R injury.展开更多
Objective:Investigation of the regulatory mechanisms of cell stemness in cholangiocarcinoma(CCA)is essential for developing effective therapies to improve patient outcomes.The purpose of this study was to investigate ...Objective:Investigation of the regulatory mechanisms of cell stemness in cholangiocarcinoma(CCA)is essential for developing effective therapies to improve patient outcomes.The purpose of this study was to investigate the function and regulatory mechanism of m6A modifications in CCA cell stemness.Methods:Interleukin 6(IL-6)treatment was used to induce an inflammatory response,and loss-of-function studies were conducted using mammosphere culture assays.Chromatin immunoprecipitation,polysome profiling,and methylated RNA immunoprecipitation analyses were used to identify signaling pathways.The in vitro findings were verified in a mice model.Results:We first identified that m6A writers were highly expressed in CCAs and further showed that STAT3 directly bound to the gene loci of m6A writers,showing that IL-6/STAT3 signaling regulated expressions of m6A writers.Downregulating m6A writers prevented cell proliferation and migration in vitro and suppressed CCA tumorigenesis in vivo.Notably,the knockdown of m6A writers inhibited CCA cell stemness that was triggered by IL-6 treatment.Mechanistically,IGF2BP2 was bound to CTNNB1 transcripts,significantly enhancing their stability and translation,and conferring stem-like properties.Finally,we confirmed that the combination of m6A writers,IGF2BP2,and CTNNB1 distinguished CCA tissues from normal tissues.Conclusions:Overall,this study showed that the IL-6-triggered inflammatory response facilitated the expressions of m6A writers and cell stemness in an m6A-IGF2BP2-dependent manner.Furthermore,the study showed that m6A modification was a targetable mediator of the response to inflammation factor exposure,was a potential diagnostic biomarker for CCA,and was critical to the progression of CCA.展开更多
N6-methyladenosine(m6A)is the most abundant and well-investigated internal RNA modification in eukaryotic RNAs,affecting its target gene expression by controlling RNA localization,splicing,stability,and translation.m6...N6-methyladenosine(m6A)is the most abundant and well-investigated internal RNA modification in eukaryotic RNAs,affecting its target gene expression by controlling RNA localization,splicing,stability,and translation.m6A modifications are regulated by m6A methyltransferase complex,demethylase,and reading proteins.Insulin-like growth factor-2 mRNA-binding protein 1(IGF2BP1),a member of a conserved family of single-stranded RNA-binding proteins,has recently been identified as a vital m6A reading protein.IGF2BP1 is highly expressed in various tumors and is associated with poor prognosis and treatment resistance.Furthermore,previous studies have shown that IGF2BP1 plays critical roles in regulating various cancer hallmarks,including sustained cell proliferation,cell death resistance,activation of invasion and metastasis,deregulated cellular energetics,immune evasion,and unlocking phenotypic plasticity.IGF2BP1 could promote the expression of cancer-related genes by recognizing their m6A sites,thereby altering cell characteristics,and eventually,malignancy.Therefore,IGF2BP1 might be a potential target for tumor diagnosis and anti-tumor therapeutic strategies.This review summarizes the current knowledge on the functional roles and underlying molecular mechanisms of IGF2BP1 in regulating cancer hallmarks.Moreover,we discuss the prospects of IGF2BP1 as a potential tumor diagnosis marker,as well as a potential target for an anti-tumor therapeutic strategy.展开更多
Accumulating evidence indicates that RNA methylation at N6-methyladenosine(m6A)plays an important regulatory role in gene expression and aberrant mRNA m6A modification is often associated with a variety of cancers.How...Accumulating evidence indicates that RNA methylation at N6-methyladenosine(m6A)plays an important regulatory role in gene expression and aberrant mRNA m6A modification is often associated with a variety of cancers.However,little is known whether and how m6A-modification impacts long non-coding RNA(lncRNA)and lncRNA-mediated tumorigenesis,particularly in pancreatic ductal adenocarcinoma(PDAC).In the present study,we report that a previously uncharacterized lncRNA,LINC00901,promotes pancreatic cancer cell growth and invasion and moreover,LINC00901 is subject to m6A modification which regulates its expression.In this regard,YTHDF1 serves as a reader for the m6A modified LINC00901 and downregulates the LINC00901 level.Notably,two conserved m6A sites in LINC00901 are critical to the recognition of LINC00901 by YTHDF1.Finally,RNA sequencing(RNA-seq)and gene function analysis revealed that LINC00901 positively regulates MYC through upregulation of IGF2BP2,a known RNA binding protein that can enhance MYC mRNA stability.Together,our results suggest that there is a LINC00901-IGF2BP2-MYC axis through which LINC00901 promotes PDAC progression in an m6A dependent manner.展开更多
Nonalcoholic steatohepatitis(NASH)has emerged as the major cause of end-stage liver diseases.However,an incomplete understanding of its molecular mechanisms severely dampens the development of pharmacotherapies.In the...Nonalcoholic steatohepatitis(NASH)has emerged as the major cause of end-stage liver diseases.However,an incomplete understanding of its molecular mechanisms severely dampens the development of pharmacotherapies.In the present study,through systematic screening of genome-wide mRNA expression from three mouse models of hepatic inflammation and fibrosis,we identified IGF2BP2,an N6-methyladenosine modification reader,as a key regulator that promotes NASH progression in mice.Adenovirus or adeno-associated virus-mediated overexpression of IGF2BP2 could induce liver steatosis,inflammation,and fibrosis in mice,at least in part,by increasing Tab2 mRNA stability.Besides,hepatic overexpression of IGF2BP2 mimicked gene expression profiles and molecular pathways of human NASH livers.Of potential clinical significance,IGF2BP2 expression is significantly upregulated in the livers of NASH patients.Moreover,knockdown of IGF2BP2 substantially alleviated liver injury,inflammation,and fibrosis in diet-induced NASH mice.Taken together,our findings reveal an important role of IGF2BP2 in NASH,which may provide a new therapeutic target for the treatment of NASH.展开更多
基金National Key Research and Development Program of China(2023YFC2505900)National Natural Science Foundation of China(92269204,82171755,92369106,82171749,82171811,82073184)+1 种基金Military Outstanding Youth Program(2020QN06119,01-SWK JYCJJ07,23SWAQ53)Program of Leading Talents in Shanghai,and Shanghai Shuguang Program(20SG39)。
文摘Background Liver ischemia/reperfusion(I/R)injury is usually caused by hepatic inflow occlusion during liver surgery,and is frequently observed during war wounds and trauma.Hepatocyte ferroptosis plays a critical role in liver I/R injury,however,it remains unclear whether this process is controlled or regulated by members of the DEAD/DExH-box helicase(DDX/DHX)family.Methods The expression of DDX/DHX family members during liver I/R injury was screened using transcriptome analysis.Hepatocyte-specific Dhx58 knockout mice were constructed,and a partial liver I/R operation was performed.Single-cell RNA sequencing(scRNA-seq)in the liver post I/R suggested enhanced ferroptosis by Dhx58hep−/−.The mRNAs and proteins associated with DExH-box helicase 58(DHX58)were screened using RNA immunoprecipitation-sequencing(RIP-seq)and IP-mass spectrometry(IP-MS).Results Excessive production of reactive oxygen species(ROS)decreased the expression of the IFN-stimulated gene Dhx58 in hepatocytes and promoted hepatic ferroptosis,while treatment using IFN-αincreased DHX58 expression and prevented ferroptosis during liver I/R injury.Mechanistically,DHX58 with RNA-binding activity constitutively associates with the mRNA of glutathione peroxidase 4(GPX4),a central ferroptosis suppressor,and recruits the m6A reader YT521-B homology domain containing 2(YTHDC2)to promote the translation of Gpx4 mRNA in an m6A-dependent manner,thus enhancing GPX4 protein levels and preventing hepatic ferroptosis.Conclusions This study provides mechanistic evidence that IFN-αstimulates DHX58 to promote the translation of m6A-modified Gpx4 mRNA,suggesting the potential clinical application of IFN-αin the prevention of hepatic ferroptosis during liver I/R injury.
基金supported by the National Natural Science Foundation of China(Grant No.81772621)the National Key R&D Program of China(Grant No.2017YFA0504400).
文摘Objective:Investigation of the regulatory mechanisms of cell stemness in cholangiocarcinoma(CCA)is essential for developing effective therapies to improve patient outcomes.The purpose of this study was to investigate the function and regulatory mechanism of m6A modifications in CCA cell stemness.Methods:Interleukin 6(IL-6)treatment was used to induce an inflammatory response,and loss-of-function studies were conducted using mammosphere culture assays.Chromatin immunoprecipitation,polysome profiling,and methylated RNA immunoprecipitation analyses were used to identify signaling pathways.The in vitro findings were verified in a mice model.Results:We first identified that m6A writers were highly expressed in CCAs and further showed that STAT3 directly bound to the gene loci of m6A writers,showing that IL-6/STAT3 signaling regulated expressions of m6A writers.Downregulating m6A writers prevented cell proliferation and migration in vitro and suppressed CCA tumorigenesis in vivo.Notably,the knockdown of m6A writers inhibited CCA cell stemness that was triggered by IL-6 treatment.Mechanistically,IGF2BP2 was bound to CTNNB1 transcripts,significantly enhancing their stability and translation,and conferring stem-like properties.Finally,we confirmed that the combination of m6A writers,IGF2BP2,and CTNNB1 distinguished CCA tissues from normal tissues.Conclusions:Overall,this study showed that the IL-6-triggered inflammatory response facilitated the expressions of m6A writers and cell stemness in an m6A-IGF2BP2-dependent manner.Furthermore,the study showed that m6A modification was a targetable mediator of the response to inflammation factor exposure,was a potential diagnostic biomarker for CCA,and was critical to the progression of CCA.
基金supported by grants from the National Natural Science Foundation of China(No.82173029,32270778,and 82372655)the Natural Science Foundation of Chongqing,China(No.CSTB2022NSCQ-MSX0611,CSTB2022NSCQ-MSX0612)the Talent Project of Chongqing University Jiangjin Hospital(Chongqing,China)(No.2024LJXM005).
文摘N6-methyladenosine(m6A)is the most abundant and well-investigated internal RNA modification in eukaryotic RNAs,affecting its target gene expression by controlling RNA localization,splicing,stability,and translation.m6A modifications are regulated by m6A methyltransferase complex,demethylase,and reading proteins.Insulin-like growth factor-2 mRNA-binding protein 1(IGF2BP1),a member of a conserved family of single-stranded RNA-binding proteins,has recently been identified as a vital m6A reading protein.IGF2BP1 is highly expressed in various tumors and is associated with poor prognosis and treatment resistance.Furthermore,previous studies have shown that IGF2BP1 plays critical roles in regulating various cancer hallmarks,including sustained cell proliferation,cell death resistance,activation of invasion and metastasis,deregulated cellular energetics,immune evasion,and unlocking phenotypic plasticity.IGF2BP1 could promote the expression of cancer-related genes by recognizing their m6A sites,thereby altering cell characteristics,and eventually,malignancy.Therefore,IGF2BP1 might be a potential target for tumor diagnosis and anti-tumor therapeutic strategies.This review summarizes the current knowledge on the functional roles and underlying molecular mechanisms of IGF2BP1 in regulating cancer hallmarks.Moreover,we discuss the prospects of IGF2BP1 as a potential tumor diagnosis marker,as well as a potential target for an anti-tumor therapeutic strategy.
基金supported by grants from National Natural Science Foundation of China(No.82072703 to WP,No.81772575 and No.81972455 to LY)US Department of Defense(No.CA170314 to YM).
文摘Accumulating evidence indicates that RNA methylation at N6-methyladenosine(m6A)plays an important regulatory role in gene expression and aberrant mRNA m6A modification is often associated with a variety of cancers.However,little is known whether and how m6A-modification impacts long non-coding RNA(lncRNA)and lncRNA-mediated tumorigenesis,particularly in pancreatic ductal adenocarcinoma(PDAC).In the present study,we report that a previously uncharacterized lncRNA,LINC00901,promotes pancreatic cancer cell growth and invasion and moreover,LINC00901 is subject to m6A modification which regulates its expression.In this regard,YTHDF1 serves as a reader for the m6A modified LINC00901 and downregulates the LINC00901 level.Notably,two conserved m6A sites in LINC00901 are critical to the recognition of LINC00901 by YTHDF1.Finally,RNA sequencing(RNA-seq)and gene function analysis revealed that LINC00901 positively regulates MYC through upregulation of IGF2BP2,a known RNA binding protein that can enhance MYC mRNA stability.Together,our results suggest that there is a LINC00901-IGF2BP2-MYC axis through which LINC00901 promotes PDAC progression in an m6A dependent manner.
基金This study was supported by the National Key Research and Development Program of China(2018YFA0800402)the Shanghai Outstanding Academic Leaders Projects(21XD1423400)+3 种基金the Basic Research of Science,and Technology Innovation Action Plan(21JC1401300)Shanghai Sailing Program by Shanghai Municipal Science and Technology Committee(22YF1432800)China Postdoctoral Science Foundation Funded Project(2021M702183)the Youth Cultivation Project of Shanghai Jiao Tong University Affiliated Sixth People’s Hospital(ynqn202107).
文摘Nonalcoholic steatohepatitis(NASH)has emerged as the major cause of end-stage liver diseases.However,an incomplete understanding of its molecular mechanisms severely dampens the development of pharmacotherapies.In the present study,through systematic screening of genome-wide mRNA expression from three mouse models of hepatic inflammation and fibrosis,we identified IGF2BP2,an N6-methyladenosine modification reader,as a key regulator that promotes NASH progression in mice.Adenovirus or adeno-associated virus-mediated overexpression of IGF2BP2 could induce liver steatosis,inflammation,and fibrosis in mice,at least in part,by increasing Tab2 mRNA stability.Besides,hepatic overexpression of IGF2BP2 mimicked gene expression profiles and molecular pathways of human NASH livers.Of potential clinical significance,IGF2BP2 expression is significantly upregulated in the livers of NASH patients.Moreover,knockdown of IGF2BP2 substantially alleviated liver injury,inflammation,and fibrosis in diet-induced NASH mice.Taken together,our findings reveal an important role of IGF2BP2 in NASH,which may provide a new therapeutic target for the treatment of NASH.
