Hepatocellular carcinoma(HCC) is one of the most prevalent malignancies worldwide and the second leading cause of death among all cancer types. Deregulation of the networks of tissue-specific transcription factors(TFs...Hepatocellular carcinoma(HCC) is one of the most prevalent malignancies worldwide and the second leading cause of death among all cancer types. Deregulation of the networks of tissue-specific transcription factors(TFs) observed in HCC leads to profound changes in the hepatic transcriptional program that facilitates tumor progression. In addition, recent reports suggest that substantial aberrations in the production of TF isoforms occur in HCC. In vitro experiments have identified distinct isoform-specific regulatory functions and related biological effects of liver-specific TFs that are implicated in carcinogenesis, which may be relevant for tumor progression and clinical outcome. This study reviews available data on the expression of isoforms of liver-specific and ubiquitous TFs in the liver and HCC and their effects, including HNF4α, C/EBPs, p73 and TCF7 L2, and indicates that assessment of the ratio of isoforms and targeting specific TF variants may be beneficial for the prognosis and treatment of HCC.展开更多
Protein arginine methyltransferases(PRMTs) catalyze the methylation of a variety of protein substrates, many of which have been linked to the development, progression and aggressiveness of different types of cancer. M...Protein arginine methyltransferases(PRMTs) catalyze the methylation of a variety of protein substrates, many of which have been linked to the development, progression and aggressiveness of different types of cancer. Moreover, aberrant expression of PRMTs has been observed in several cancer types. While the link between PRMTs and cancer is a relatively new area of interest, the functional implications documented thus far warrant further investigations into its therapeutic potential. However, the expression of these enzymes and the regulation of their activity in cancer are still significantly understudied. Currently there are nine main members of the PRMT family. Further, the existence of alternatively spliced isoforms for several of these family members provides an additional layer of complexity. Specifically, PRMT1, PRMT2, CARM1 and PRMT7 have been shown to have alternative isoforms and others may be currently unrealized. Our knowledge with respect to the relative expression and the specific functions of these isoforms is largely lacking and needs attention. Here we present a review of the current knowledge of theknown alternative PRMT isoforms and provide a rationale for how they may impact on cancer and represent potentially useful targets for the development of novel therapeutic strategies.展开更多
Polypyrimidine tract-binding protein 1(PTBP1)plays an essential role in splicing and is expressed in almost all cell types in humans,unlike the other proteins of the PTBP family.PTBP1 mediates several cellular process...Polypyrimidine tract-binding protein 1(PTBP1)plays an essential role in splicing and is expressed in almost all cell types in humans,unlike the other proteins of the PTBP family.PTBP1 mediates several cellular processes in certain types of cells,including the growth and differentiation of neuronal cells and activation of immune cells.Its function is regulated by various molecules,including micro RNAs(mi RNAs),long non-coding RNAs(lnc RNAs),and RNA-binding proteins.PTBP1 plays roles in various diseases,particularly in some cancers,including colorectal cancer,renal cell cancer,breast cancer,and glioma.In cancers,it acts mainly as a regulator of glycolysis,apoptosis,proliferation,tumorigenesis,invasion,and migration.The role of PTBP1 in cancer has become a popular research topic in recent years,and this research has contributed greatly to the formulation of a useful therapeutic strategy for cancer.In this review,we summarize recent findings related to PTBP1 and discuss how it regulates the development of cancer cells.展开更多
Fragile X (Fra (X)) syndrome is the most frequent cause of inherited mentalretardation, and it is associated with the fragile site at Xq27.3. In 1991, the FMR1(fragile X mental retardation 1) gene was cloned in the vi...Fragile X (Fra (X)) syndrome is the most frequent cause of inherited mentalretardation, and it is associated with the fragile site at Xq27.3. In 1991, the FMR1(fragile X mental retardation 1) gene was cloned in the vicinity of this site. The muationand abnormal expression of FMR1 are the direct causes of Fra(X) syndrome. The展开更多
Metabolic-associated fatty liver disease(MAFLD),which is previously known as non-alcoholic fatty liver disease(NAFLD),represents a major health concern worldwide with limited therapy.Here,we provide evidence that ferr...Metabolic-associated fatty liver disease(MAFLD),which is previously known as non-alcoholic fatty liver disease(NAFLD),represents a major health concern worldwide with limited therapy.Here,we provide evidence that ferroptosis,a novel form of regulated cell death characterized by iron-driven lipid peroxidation,was comprehensively activated in liver tissues from MAFLD patients.The canonical-GPX4(cGPX4),which is the most important negative controller of ferroptosis,is downregulated at protein but not mRNA level.Interestingly,a non-canonical GPX4 transcript-variant is induced(inducible-GPX4,iGPX4)in MAFLD condition.The high fat-fructose/sucrose diet(HFFD)and methionine/choline-deficient diet(MCD)-induced MAFLD pathologies,including hepatocellular ballooning,steatohepatitis andfibrosis,were attenuated and aggravated,respectively,in cGPX4-and iGPX4-knockin mice.cGPX4 and iGPX4 isoforms also displayed opposing effects on oxidative stress and ferroptosis in hepatocytes.Knockdown of iGPX4 by siRNA alleviated lipid stress,ferroptosis and cell injury.Mechanistically,the triggered iGPX4 interacts with cGPX4 to facilitate the transformation of cGPX4 from enzymatic-active monomer to enzymatic-inactive oligomers upon lipid stress,and thus promotes ferroptosis.Co-immunoprecipitation and nano LC–MS/MS analyses confirmed the interaction between iGPX4 and cGPX4.Our results reveal a detrimental role of non-canonical GPX4 isoform in ferroptosis,and indicate selectively targeting iGPX4 may be a promising therapeutic strategy for MAFLD.展开更多
基金Supported by Russian Foundation for Basic Research,contract No.18-34-00816\18
文摘Hepatocellular carcinoma(HCC) is one of the most prevalent malignancies worldwide and the second leading cause of death among all cancer types. Deregulation of the networks of tissue-specific transcription factors(TFs) observed in HCC leads to profound changes in the hepatic transcriptional program that facilitates tumor progression. In addition, recent reports suggest that substantial aberrations in the production of TF isoforms occur in HCC. In vitro experiments have identified distinct isoform-specific regulatory functions and related biological effects of liver-specific TFs that are implicated in carcinogenesis, which may be relevant for tumor progression and clinical outcome. This study reviews available data on the expression of isoforms of liver-specific and ubiquitous TFs in the liver and HCC and their effects, including HNF4α, C/EBPs, p73 and TCF7 L2, and indicates that assessment of the ratio of isoforms and targeting specific TF variants may be beneficial for the prognosis and treatment of HCC.
基金Supported by Cancer projects in the C télab are funded through the Cancer Research Society,Canadian Research Institutes of Health Research and Canadian Breast Cancer Foundation
文摘Protein arginine methyltransferases(PRMTs) catalyze the methylation of a variety of protein substrates, many of which have been linked to the development, progression and aggressiveness of different types of cancer. Moreover, aberrant expression of PRMTs has been observed in several cancer types. While the link between PRMTs and cancer is a relatively new area of interest, the functional implications documented thus far warrant further investigations into its therapeutic potential. However, the expression of these enzymes and the regulation of their activity in cancer are still significantly understudied. Currently there are nine main members of the PRMT family. Further, the existence of alternatively spliced isoforms for several of these family members provides an additional layer of complexity. Specifically, PRMT1, PRMT2, CARM1 and PRMT7 have been shown to have alternative isoforms and others may be currently unrealized. Our knowledge with respect to the relative expression and the specific functions of these isoforms is largely lacking and needs attention. Here we present a review of the current knowledge of theknown alternative PRMT isoforms and provide a rationale for how they may impact on cancer and represent potentially useful targets for the development of novel therapeutic strategies.
基金Project supported by the National Natural Science Foundation of China(Nos.81773179,81272972,and 81472355)the Program for New Century Excellent Talents in University(No.NCET-10-0790)+2 种基金the Hunan Provincial Science and Technology Department(Nos.2016JC 2049 and 2014FJ6006)the Hunan Provincial Natural Science Foundation of China(No.2016JJ2172)the Undergraduate Training Programs for Innovation and Entrepreneurship(Nos.201810533368,GS201910533474,and GS201910533236),China.
文摘Polypyrimidine tract-binding protein 1(PTBP1)plays an essential role in splicing and is expressed in almost all cell types in humans,unlike the other proteins of the PTBP family.PTBP1 mediates several cellular processes in certain types of cells,including the growth and differentiation of neuronal cells and activation of immune cells.Its function is regulated by various molecules,including micro RNAs(mi RNAs),long non-coding RNAs(lnc RNAs),and RNA-binding proteins.PTBP1 plays roles in various diseases,particularly in some cancers,including colorectal cancer,renal cell cancer,breast cancer,and glioma.In cancers,it acts mainly as a regulator of glycolysis,apoptosis,proliferation,tumorigenesis,invasion,and migration.The role of PTBP1 in cancer has become a popular research topic in recent years,and this research has contributed greatly to the formulation of a useful therapeutic strategy for cancer.In this review,we summarize recent findings related to PTBP1 and discuss how it regulates the development of cancer cells.
基金Project supported by the State Education Commission and the National Natural Science Foundation of China.
文摘Fragile X (Fra (X)) syndrome is the most frequent cause of inherited mentalretardation, and it is associated with the fragile site at Xq27.3. In 1991, the FMR1(fragile X mental retardation 1) gene was cloned in the vicinity of this site. The muationand abnormal expression of FMR1 are the direct causes of Fra(X) syndrome. The
基金supported by the grants from National Natural Science Foundation of China (82073915, 91849135, 81673485, 81773719, 81973312 and 81971306)National Key Research and Development Project (2018YFA0108301, China)+2 种基金Shanghai Science and Technology Commission Experimental Animal Grants (21XD1424900, 19140904700, 19140904900 and 21S11901200, China)Shanghai Shuguang Program (19SG32, China)Shanghai “Rising Stars of Medical Talent” Youth Development ProgramYouth Medical Talents-Clinical Pharmacist Program [SHWRS(2020)_087, China]
文摘Metabolic-associated fatty liver disease(MAFLD),which is previously known as non-alcoholic fatty liver disease(NAFLD),represents a major health concern worldwide with limited therapy.Here,we provide evidence that ferroptosis,a novel form of regulated cell death characterized by iron-driven lipid peroxidation,was comprehensively activated in liver tissues from MAFLD patients.The canonical-GPX4(cGPX4),which is the most important negative controller of ferroptosis,is downregulated at protein but not mRNA level.Interestingly,a non-canonical GPX4 transcript-variant is induced(inducible-GPX4,iGPX4)in MAFLD condition.The high fat-fructose/sucrose diet(HFFD)and methionine/choline-deficient diet(MCD)-induced MAFLD pathologies,including hepatocellular ballooning,steatohepatitis andfibrosis,were attenuated and aggravated,respectively,in cGPX4-and iGPX4-knockin mice.cGPX4 and iGPX4 isoforms also displayed opposing effects on oxidative stress and ferroptosis in hepatocytes.Knockdown of iGPX4 by siRNA alleviated lipid stress,ferroptosis and cell injury.Mechanistically,the triggered iGPX4 interacts with cGPX4 to facilitate the transformation of cGPX4 from enzymatic-active monomer to enzymatic-inactive oligomers upon lipid stress,and thus promotes ferroptosis.Co-immunoprecipitation and nano LC–MS/MS analyses confirmed the interaction between iGPX4 and cGPX4.Our results reveal a detrimental role of non-canonical GPX4 isoform in ferroptosis,and indicate selectively targeting iGPX4 may be a promising therapeutic strategy for MAFLD.