Background KCNJ11, ABCC8, PPARG, and HNF4A have been found to be associated with type 2 diabetes in populations with different genetic backgrounds. The aim of this study was to test, in a Chinese Han population from B...Background KCNJ11, ABCC8, PPARG, and HNF4A have been found to be associated with type 2 diabetes in populations with different genetic backgrounds. The aim of this study was to test, in a Chinese Han population from Beijing, whether the genetic variants in these four genes were associated with genetic predisposition to type 2 diabetes. Methods We studied the association of four representative SNPs in KCNJ11, ABCC8, PPARG, and HNF4A by genotyping them using ABI SNaPshot Multiplex System in 400 unrelated type 2 diabetic patients and 400 unrelated normoglycaemic subjects. Results rs5219（E23K） in KCNJ11 was associated with genetic susceptibility to type 2 diabetes （OR=1.400 with 95% CI 1.117 1.755, P=0.004 under an additive model, 0R=1.652 with 95% CI 1.086 2.513, P=0.019 under a recessive model, and OR=1.521 with 95% Cl 1.089 2.123, P=0.014 under a dominant model） after adjusting for sex and body mass index （BMI）. We did not find evidence of association for ABCC8 rs1799854, PPARG rs1801282 （Pro12Ala） and HNF4A rs2144908. Genotype-phenotype correlation analysis revealed that rs1799854 in ABCC8 was associated with 2-hour postprandial insulin secretion （P=0.005） after adjusting for sex, age and BMI. Although no interactions between the four variants on the risk of type 2 diabetes were detected, the multiplicative interaction between PPARG Pro12Ala and HNF4A rs2144908 was found to be associated with 2-hour postprandial insulin （P=-0.004 under an additive model for rs2144908; and P=0.001 under a dominant model for rs2144908） after adjusting for age, sex and BMI, assuming a dominant model for PPARG Pro12Ala. Conclusions Our study replicated the association of rs5219 in KCNJ11 with type 2 diabetes in Chinese Han population in Beijing. And we also observed that ABCC8 as well as the interaction between PPARG and HNF4A may contribute to post-challenge insulin secretion.展开更多
YPEL5 is a member of the Yippee-like(YPEL)gene family that is evolutionarily conserved in eukaryotic species.To date,the physiological function of YPEL5 has not been assessed due to a paucity of genetic animal models....YPEL5 is a member of the Yippee-like(YPEL)gene family that is evolutionarily conserved in eukaryotic species.To date,the physiological function of YPEL5 has not been assessed due to a paucity of genetic animal models.Here,using CRISPR/Cas9-mediated genome editing,we generated a stable ypel5^(−/−)mutant zebrafish line.Disruption of ypel5 expression leads to liver enlargement associated with hepatic cell proliferation.Meanwhile,hepatic metabolism and function are dysregulated in ypel5^(−/−)mutant zebrafish,as revealed by metabolomic and transcriptomic analyses.Mechanistically,Hnf4a is identified as a crucial downstream mediator that is positively regulated by Ypel5.Zebrafish hnf4a overexpression could largely rescue ypel5 deficiencyinduced hepatic defects.Furthermore,PPARαsignaling mediates the regulation of Hnf4a by Ypel5 through directly binding to the transcriptional enhancer of the Hnf4a gene.Herein,this work demonstrates an essential role of Ypel5 in hepatocyte proliferation and function and provides the first in vivo evidence for a physiological role of the ypel5 gene in vertebrates.展开更多
Background: Tumor hypoxia is associated with metastasis and resistance to chemotherapy and radiotherapy. Genes involved in oxygen-sensing are clinically relevant and have significant implications for prognosis. In thi...Background: Tumor hypoxia is associated with metastasis and resistance to chemotherapy and radiotherapy. Genes involved in oxygen-sensing are clinically relevant and have significant implications for prognosis. In this study, we examined the pan-cancer prognostic significance of oxygen-sensing genes from the 2-oxoglutarate-dependent oxygenase family. Methods: A multi-cohort, retrospective study of transcriptional profiles of 20,752 samples of 25 types of cancer was performed to identify pan-cancer prognostic signatures of 2-oxoglutarate-dependent oxygenase gene family (a family of oxygen-dependent enzymes consisting of 61 genes). We defined minimal prognostic gene sets using three independent pancreatic cancer cohorts (n = 681). We identified two signatures, each consisting of 5 genes. The ability of the signa-tures in predicting survival was tested using Cox regression and receiver operating characteristic (ROC) curve analyses. Results: Signature 1 (KDM8, KDM6B, P4HTM, ALKBH4, ALKBH7) and signature 2 (KDM3A, P4HA1, ASPH, PLOD1, PLOD2) were associated with good and poor prognosis. Signature 1 was prognostic in 8 cohorts representing 6 cancer types (n = 2627): bladder urothelial carcinoma (P = 0.039), renal papillary cell carcinoma (P = 0.013), liver cancer (P = 0.033 and P = 0.025), lung adenocarcinoma (P = 0.014), pancreatic adenocarcinoma (P < 0.001 and P = 0.040), and uterine corpus endometrial carcinoma (P < 0.001). Signature 2 was prognostic in 12 cohorts representing 9 cancer types (n = 4134): bladder urothelial carcinoma (P = 0.039), cervical squamous cell carcinoma and endocervical adenocar-cinoma (P = 0.035), head and neck squamous cell carcinoma (P = 0.038), renal clear cell carcinoma (P = 0.012), renal papillary cell carcinoma (P = 0.002), liver cancer (P < 0.001, P < 0.001), lung adenocarcinoma (P = 0.011), pancreatic adenocarcinoma (P = 0.002, P = 0.018, P < 0.001), and gastric adenocarcinoma (P = 0.004). Multivariate Cox regression confirmed independent clinical relevance of the signatures in these 展开更多
Objective:Hepatocyte nuclear factor 4α(HNF4 A)has been demonstrated to be an oncogene in gastric cancer(GC).However,the roles of different HNF4 A isoforms derived from the 2 different promoters(P1 and P2)and the unde...Objective:Hepatocyte nuclear factor 4α(HNF4 A)has been demonstrated to be an oncogene in gastric cancer(GC).However,the roles of different HNF4 A isoforms derived from the 2 different promoters(P1 and P2)and the underlying mechanisms remain obscure.Methods:The expression and prognostic values of P1-and P2-HNF4 A were evaluated in The Cancer Genome Atlas(TCGA)databases and GC tissues.Then,functional assays of P1-and P2-HNF4 A were conducted both in vivo and in vitro.High-throughput RNA-seq was employed to profile downstream pathways in P1-and P2-HNF4 A-overexpressing GC cells.The expression and gene regulation network of the candidate target genes identified by RNA-seq were characterized based on data mining and functional assays.Results:HNF4 A amplification was a key characteristic of GC in TCGA databases,especially for the intestinal type and early stage.Moreover,P1-HNF4 A expression was significantly higher in tumor tissues than in adjacent non-tumor tissues(P<0.05),but no significant differences were found in P2-HNF4 A expression(P>0.05).High P1-HNF4 A expression indicated poor prognoses in GC patients(P<0.01).Furthermore,P1-HNF4 A overexpression significantly promoted SGC7901 and BGC823 cell proliferation,invasion and migration in vitro(P<0.01).Murine xenograft experiments showed that P1-HNF4 A overexpression promoted tumor growth(P<0.05).Mechanistically,RNA-seq showed that the cytokine-cytokine receptor interactions pathway was mostly enriched in P1-HNF4 A-overexpressing GC cells.Finally,chemokine(C-C motif)ligand 15 was identified as a direct target of P1-HNF4 A in GC tissues.Conclusions:P1-HNF4 A was the main oncogene during GC progression.The cytokine-cytokine receptor interaction pathway played a pivotal role and may be a promising therapeutic target.展开更多
Hepatocarcinogenesis, as other epithelial malignancies, has been proved to be a multistep process that, starting from mutagenic events, allows the transformed liver cell to evolve towards a more aggressive phenotype, ...Hepatocarcinogenesis, as other epithelial malignancies, has been proved to be a multistep process that, starting from mutagenic events, allows the transformed liver cell to evolve towards a more aggressive phenotype, characterized by the acquisition of migratory/invasive and stem-cell-like properties. Hepatocellular carcinoma(HCC)can originate from both mature hepatocytes and liver precursor/stem cells. Whatever its origin, a common feature of advanced-stage HCC is the reduction or lack of expression of master genes of epithelial/hepatocyte differentiation, i.e. members of the liver enriched transcription factors(LEFTs)family like HNF4α, and conversely an increased expression of epithelial-to-mesenchymal transition(EMT)master genes, i.e. the transcriptional repressors belonging to the Snail family. Recently, it has emerged as members of these families are capable to directly repress each other and to regulate in opposite manner target genes involved in stemness and in hepatocyte differentiation, thus influencing cell outcome between epithelial/differentiated/poor aggressive and mesenchymal/undifferentiated/aggressive phenotype. Consequently, the restoration of LEFT functions in invasive HCC could represent an important goal for anti-cancer therapies. However, any strategy based on gene transfer needs to take in account the influence of micro-environmental factors in HCC tumor niche, like TGFb, responsible for shifting the described balance in tumor cell towards the acquisition of stem-cell like properties and invasiveness, through Snail/EMT induction and LEFTs downregulation. The presence of this cytokine, indeed, was shown to override both anti-EMT and tumor suppressor activity of the ectopically expressed HNF4α protein. In this review, the rationale to propose implementation of HCC gene therapy will be discussed.展开更多
The liver is essential for survival due to its critical role in the regulation of metabolic homeostasis.Metabolism of xenobiotics,such as environmental chemicals and drugs by the liver protects us from toxic effects o...The liver is essential for survival due to its critical role in the regulation of metabolic homeostasis.Metabolism of xenobiotics,such as environmental chemicals and drugs by the liver protects us from toxic effects of these xenobiotics,whereas metabolism of cholesterol,bile acids(BAs),lipids,and glucose provide key building blocks and nutrients to promote the growth or maintain the survival of the organism.As a wellestablished master regulator of liver development and function,hepatocyte nuclear factor 4 alpha(HNF4α)plays a critical role in regulating a large number of key genes essential for the metabolism of xenobiotics,metabolic wastes,and nutrients.The expression and activity of HNF4α is regulated by diverse hormonal and signaling pathways such as growth hormone,glucocorticoids,thyroid hormone,insulin,transforming growth factor-β,estrogen,and cytokines.HNF4α appears to play a central role in orchestrating the transduction of extracellular hormonal signaling and intracellular stress/nutritional signaling onto transcriptional changes in the liver.There have been a few reviews on the regulation of drug metabolism,lipid metabolism,cell proliferation,and inflammation by HNF4α.However,the knowledge on how the expression and transcriptional activity of HNF4α is modulated remains scattered.Herein I provide comprehensive review on the regulation of expression and transcriptional activity of HNF4α,and how HNF4α crosstalks with diverse extracellular and intracellular signaling pathways to regulate genes essential in liver pathophysiology.展开更多
Pancreatic ductal adenocarcinoma(PDAC)has poor prognosis due to limited therapeutic options.This study examines the roles of genome-wide association study identified PDAC-associated genes as therapeutic targets.We hav...Pancreatic ductal adenocarcinoma(PDAC)has poor prognosis due to limited therapeutic options.This study examines the roles of genome-wide association study identified PDAC-associated genes as therapeutic targets.We have identified HNF4G gene whose silencing most effectively repressed PDAC cell invasiveness.HNF4G overexpression is induced by the deficiency of transcriptional factor and tumor suppressor SMAD4.Increased HNF4G are correlated with SMAD4 deficiency in PDAC tumor samples and associated with metastasis and poor survival time in xenograft animal model and in patients with PDAC(log-rank P=0.036;HR=1.60,95%CI=1.03–2.47).We have found that Metformin suppresses HNF4G activity via AMPK-mediated phosphorylation-coupled ubiquitination degradation and inhibits in vitro invasion and in vivo metastasis of PDAC cells with SMAD4 deficiency.Furthermore,Metformin treatment significantly improve clinical outcomes and survival in patients with SMAD4-deficient PDAC(log-rank P=0.022;HR=0.31,95%CI=0.14–0.68)but not in patients with SMAD4-normal PDAC.Pathway analysis shows that HNF4G may act in PDAC through the cell-cell junction pathway.These results indicate that SMAD4 deficiency-induced overexpression of HNF4G plays a critical oncogenic role in PDAC progression and metastasis but may form a druggable target for Metformin treatment.展开更多
Hepatocyte nuclear factor 1 alpha(HNF1A),hepatocyte nuclear factor 4 alpha(HNF4A),and forkhead box protein A2(FOXA2)are key transcription factors that regulate a complex gene network in the liver,cre-ating a regulator...Hepatocyte nuclear factor 1 alpha(HNF1A),hepatocyte nuclear factor 4 alpha(HNF4A),and forkhead box protein A2(FOXA2)are key transcription factors that regulate a complex gene network in the liver,cre-ating a regulatory transcriptional loop.The Encode and ChIP-Atlas databases identify the recognition sites of these transcription factors in many glycosyltransferase genes.Our in silico analysis of HNF1A,HNF4A.and FOXA2 binding to the ten candidate glyco-genes studied in this work confirms a significant enrich-ment of these transcription factors specifically in the liver.Our previous studies identified HNF1A as a master regulator of fucosylation,glycan branching,and galactosylation of plasma glycoproteins.Here,we aimed to functionally validate the role of the three transcription factors on downstream glyco-gene transcriptional expression and the possible effect on glycan phenotype.We used the state-of-the-art clus-tered regularly interspaced short palindromic repeats/dead Cas9(CRISPR/dCas9)molecular tool for the downregulation of the HNF1A,HNF4A,and FOXA2 genes in HepG2 cells-a human liver cancer cell line.The results show that the downregulation of all three genes individually and in pairs affects the transcrip-tional activity of many glyco-genes,although downregulation of glyco-genes was not always followed by an unambiguous change in the corresponding glycan structures.The effect is better seen as an overall change in the total HepG2 N-glycome,primarily due to the extension of biantennary glycans.We propose an alternative way to evaluate the N-glycome composition via estimating the overall complexity of the glycome by quantifying the number of monomers in each glycan structure.We also propose a model showing feedback loops with the mutual activation of HNF1A-FOXA2 and HNF4A-FOXA2 affecting glyco-genes and protein glycosylation in HepG2 cells.展开更多
胃癌的发生是由正常胃黏膜经历慢性萎缩性胃炎、肠化生、异型增生直至胃癌发生的多阶段渐进性过程。其中肠化生是胃癌尤其是肠型胃癌重要的癌前病变。有研究证实,在肠化生及胃癌的发生过程中,性别决定区Y框蛋白2(SRY related HMG box-2,...胃癌的发生是由正常胃黏膜经历慢性萎缩性胃炎、肠化生、异型增生直至胃癌发生的多阶段渐进性过程。其中肠化生是胃癌尤其是肠型胃癌重要的癌前病变。有研究证实,在肠化生及胃癌的发生过程中,性别决定区Y框蛋白2(SRY related HMG box-2,SOX2)、尾侧型同源转录因子2(caudal related homeobox transcription factor-2,CDX2)和肝细胞核因子(hepatocyte nuclear factor,HNF)4α均有参与,而且3个分子间存在明显相关性。因此,本文对目前SOX2、CDX2和HNF4α与胃癌的相关研究进展作一综述。展开更多
文摘Background KCNJ11, ABCC8, PPARG, and HNF4A have been found to be associated with type 2 diabetes in populations with different genetic backgrounds. The aim of this study was to test, in a Chinese Han population from Beijing, whether the genetic variants in these four genes were associated with genetic predisposition to type 2 diabetes. Methods We studied the association of four representative SNPs in KCNJ11, ABCC8, PPARG, and HNF4A by genotyping them using ABI SNaPshot Multiplex System in 400 unrelated type 2 diabetic patients and 400 unrelated normoglycaemic subjects. Results rs5219（E23K） in KCNJ11 was associated with genetic susceptibility to type 2 diabetes （OR=1.400 with 95% CI 1.117 1.755, P=0.004 under an additive model, 0R=1.652 with 95% CI 1.086 2.513, P=0.019 under a recessive model, and OR=1.521 with 95% Cl 1.089 2.123, P=0.014 under a dominant model） after adjusting for sex and body mass index （BMI）. We did not find evidence of association for ABCC8 rs1799854, PPARG rs1801282 （Pro12Ala） and HNF4A rs2144908. Genotype-phenotype correlation analysis revealed that rs1799854 in ABCC8 was associated with 2-hour postprandial insulin secretion （P=0.005） after adjusting for sex, age and BMI. Although no interactions between the four variants on the risk of type 2 diabetes were detected, the multiplicative interaction between PPARG Pro12Ala and HNF4A rs2144908 was found to be associated with 2-hour postprandial insulin （P=-0.004 under an additive model for rs2144908; and P=0.001 under a dominant model for rs2144908） after adjusting for age, sex and BMI, assuming a dominant model for PPARG Pro12Ala. Conclusions Our study replicated the association of rs5219 in KCNJ11 with type 2 diabetes in Chinese Han population in Beijing. And we also observed that ABCC8 as well as the interaction between PPARG and HNF4A may contribute to post-challenge insulin secretion.
基金supported by the National Natural Science Foundation of China(31371479).
文摘YPEL5 is a member of the Yippee-like(YPEL)gene family that is evolutionarily conserved in eukaryotic species.To date,the physiological function of YPEL5 has not been assessed due to a paucity of genetic animal models.Here,using CRISPR/Cas9-mediated genome editing,we generated a stable ypel5^(−/−)mutant zebrafish line.Disruption of ypel5 expression leads to liver enlargement associated with hepatic cell proliferation.Meanwhile,hepatic metabolism and function are dysregulated in ypel5^(−/−)mutant zebrafish,as revealed by metabolomic and transcriptomic analyses.Mechanistically,Hnf4a is identified as a crucial downstream mediator that is positively regulated by Ypel5.Zebrafish hnf4a overexpression could largely rescue ypel5 deficiencyinduced hepatic defects.Furthermore,PPARαsignaling mediates the regulation of Hnf4a by Ypel5 through directly binding to the transcriptional enhancer of the Hnf4a gene.Herein,this work demonstrates an essential role of Ypel5 in hepatocyte proliferation and function and provides the first in vivo evidence for a physiological role of the ypel5 gene in vertebrates.
文摘Background: Tumor hypoxia is associated with metastasis and resistance to chemotherapy and radiotherapy. Genes involved in oxygen-sensing are clinically relevant and have significant implications for prognosis. In this study, we examined the pan-cancer prognostic significance of oxygen-sensing genes from the 2-oxoglutarate-dependent oxygenase family. Methods: A multi-cohort, retrospective study of transcriptional profiles of 20,752 samples of 25 types of cancer was performed to identify pan-cancer prognostic signatures of 2-oxoglutarate-dependent oxygenase gene family (a family of oxygen-dependent enzymes consisting of 61 genes). We defined minimal prognostic gene sets using three independent pancreatic cancer cohorts (n = 681). We identified two signatures, each consisting of 5 genes. The ability of the signa-tures in predicting survival was tested using Cox regression and receiver operating characteristic (ROC) curve analyses. Results: Signature 1 (KDM8, KDM6B, P4HTM, ALKBH4, ALKBH7) and signature 2 (KDM3A, P4HA1, ASPH, PLOD1, PLOD2) were associated with good and poor prognosis. Signature 1 was prognostic in 8 cohorts representing 6 cancer types (n = 2627): bladder urothelial carcinoma (P = 0.039), renal papillary cell carcinoma (P = 0.013), liver cancer (P = 0.033 and P = 0.025), lung adenocarcinoma (P = 0.014), pancreatic adenocarcinoma (P < 0.001 and P = 0.040), and uterine corpus endometrial carcinoma (P < 0.001). Signature 2 was prognostic in 12 cohorts representing 9 cancer types (n = 4134): bladder urothelial carcinoma (P = 0.039), cervical squamous cell carcinoma and endocervical adenocar-cinoma (P = 0.035), head and neck squamous cell carcinoma (P = 0.038), renal clear cell carcinoma (P = 0.012), renal papillary cell carcinoma (P = 0.002), liver cancer (P < 0.001, P < 0.001), lung adenocarcinoma (P = 0.011), pancreatic adenocarcinoma (P = 0.002, P = 0.018, P < 0.001), and gastric adenocarcinoma (P = 0.004). Multivariate Cox regression confirmed independent clinical relevance of the signatures in these
基金supported by the National Natural Science Foundation of China(Grant No.81873554)Shaanxi Foundation for Innovation Team of Science and Technology(Grant No.2018TD-003)。
文摘Objective:Hepatocyte nuclear factor 4α(HNF4 A)has been demonstrated to be an oncogene in gastric cancer(GC).However,the roles of different HNF4 A isoforms derived from the 2 different promoters(P1 and P2)and the underlying mechanisms remain obscure.Methods:The expression and prognostic values of P1-and P2-HNF4 A were evaluated in The Cancer Genome Atlas(TCGA)databases and GC tissues.Then,functional assays of P1-and P2-HNF4 A were conducted both in vivo and in vitro.High-throughput RNA-seq was employed to profile downstream pathways in P1-and P2-HNF4 A-overexpressing GC cells.The expression and gene regulation network of the candidate target genes identified by RNA-seq were characterized based on data mining and functional assays.Results:HNF4 A amplification was a key characteristic of GC in TCGA databases,especially for the intestinal type and early stage.Moreover,P1-HNF4 A expression was significantly higher in tumor tissues than in adjacent non-tumor tissues(P<0.05),but no significant differences were found in P2-HNF4 A expression(P>0.05).High P1-HNF4 A expression indicated poor prognoses in GC patients(P<0.01).Furthermore,P1-HNF4 A overexpression significantly promoted SGC7901 and BGC823 cell proliferation,invasion and migration in vitro(P<0.01).Murine xenograft experiments showed that P1-HNF4 A overexpression promoted tumor growth(P<0.05).Mechanistically,RNA-seq showed that the cytokine-cytokine receptor interactions pathway was mostly enriched in P1-HNF4 A-overexpressing GC cells.Finally,chemokine(C-C motif)ligand 15 was identified as a direct target of P1-HNF4 A in GC tissues.Conclusions:P1-HNF4 A was the main oncogene during GC progression.The cytokine-cytokine receptor interaction pathway played a pivotal role and may be a promising therapeutic target.
文摘Hepatocarcinogenesis, as other epithelial malignancies, has been proved to be a multistep process that, starting from mutagenic events, allows the transformed liver cell to evolve towards a more aggressive phenotype, characterized by the acquisition of migratory/invasive and stem-cell-like properties. Hepatocellular carcinoma(HCC)can originate from both mature hepatocytes and liver precursor/stem cells. Whatever its origin, a common feature of advanced-stage HCC is the reduction or lack of expression of master genes of epithelial/hepatocyte differentiation, i.e. members of the liver enriched transcription factors(LEFTs)family like HNF4α, and conversely an increased expression of epithelial-to-mesenchymal transition(EMT)master genes, i.e. the transcriptional repressors belonging to the Snail family. Recently, it has emerged as members of these families are capable to directly repress each other and to regulate in opposite manner target genes involved in stemness and in hepatocyte differentiation, thus influencing cell outcome between epithelial/differentiated/poor aggressive and mesenchymal/undifferentiated/aggressive phenotype. Consequently, the restoration of LEFT functions in invasive HCC could represent an important goal for anti-cancer therapies. However, any strategy based on gene transfer needs to take in account the influence of micro-environmental factors in HCC tumor niche, like TGFb, responsible for shifting the described balance in tumor cell towards the acquisition of stem-cell like properties and invasiveness, through Snail/EMT induction and LEFTs downregulation. The presence of this cytokine, indeed, was shown to override both anti-EMT and tumor suppressor activity of the ectopically expressed HNF4α protein. In this review, the rationale to propose implementation of HCC gene therapy will be discussed.
基金partly supported by U.S. National Institute of Health (NIH) Grant ES019487
文摘The liver is essential for survival due to its critical role in the regulation of metabolic homeostasis.Metabolism of xenobiotics,such as environmental chemicals and drugs by the liver protects us from toxic effects of these xenobiotics,whereas metabolism of cholesterol,bile acids(BAs),lipids,and glucose provide key building blocks and nutrients to promote the growth or maintain the survival of the organism.As a wellestablished master regulator of liver development and function,hepatocyte nuclear factor 4 alpha(HNF4α)plays a critical role in regulating a large number of key genes essential for the metabolism of xenobiotics,metabolic wastes,and nutrients.The expression and activity of HNF4α is regulated by diverse hormonal and signaling pathways such as growth hormone,glucocorticoids,thyroid hormone,insulin,transforming growth factor-β,estrogen,and cytokines.HNF4α appears to play a central role in orchestrating the transduction of extracellular hormonal signaling and intracellular stress/nutritional signaling onto transcriptional changes in the liver.There have been a few reviews on the regulation of drug metabolism,lipid metabolism,cell proliferation,and inflammation by HNF4α.However,the knowledge on how the expression and transcriptional activity of HNF4α is modulated remains scattered.Herein I provide comprehensive review on the regulation of expression and transcriptional activity of HNF4α,and how HNF4α crosstalks with diverse extracellular and intracellular signaling pathways to regulate genes essential in liver pathophysiology.
基金We gratefully appreciate Y.L.,Q.C.and L.P.for their assistances in data analysis and T.L.,Y.C.and W.F.for their assistances in preparation of figures.We also thank G.Y.and Y.D.for their assistances in cell lines and animal experiments.This work was supported by National Science Fund for Distinguished Young Scholars(Grant No.81725015 to C.W.)Beijing Outstanding Young Scientist Program(Grant No.BJJWZYJH01201910023027 to C.W.)CAMS Innovation Fund for Medical Sciences(CIFMS)(Grant No.2016-I2M-3-019 to D.L.,Grant No.2016-I2M-4-002 to C.W.and Grant No.2016-I2M-1-001 to W.T.).
文摘Pancreatic ductal adenocarcinoma(PDAC)has poor prognosis due to limited therapeutic options.This study examines the roles of genome-wide association study identified PDAC-associated genes as therapeutic targets.We have identified HNF4G gene whose silencing most effectively repressed PDAC cell invasiveness.HNF4G overexpression is induced by the deficiency of transcriptional factor and tumor suppressor SMAD4.Increased HNF4G are correlated with SMAD4 deficiency in PDAC tumor samples and associated with metastasis and poor survival time in xenograft animal model and in patients with PDAC(log-rank P=0.036;HR=1.60,95%CI=1.03–2.47).We have found that Metformin suppresses HNF4G activity via AMPK-mediated phosphorylation-coupled ubiquitination degradation and inhibits in vitro invasion and in vivo metastasis of PDAC cells with SMAD4 deficiency.Furthermore,Metformin treatment significantly improve clinical outcomes and survival in patients with SMAD4-deficient PDAC(log-rank P=0.022;HR=0.31,95%CI=0.14–0.68)but not in patients with SMAD4-normal PDAC.Pathway analysis shows that HNF4G may act in PDAC through the cell-cell junction pathway.These results indicate that SMAD4 deficiency-induced overexpression of HNF4G plays a critical oncogenic role in PDAC progression and metastasis but may form a druggable target for Metformin treatment.
基金the European Structural and Investment Funded Grant"Cardio Metabolic"(#KK.01.2.1.02.0321)the Croatian National Centre of Research Excellence in Personalized Healthcare Grant(#KK.01.1.1.01.0010)+2 种基金the European Regional Development Fund Grant,project"CRISPR/Cas9-CasMouse"(#KK.01.1.1.04.0085)the European Structural and Investment Funded Project of Centre of Competence in Molecular Diagnostics(#KK.01.2.2.03.0006)the Croatian National Centre of Research Excellence in Personalized Healthcare Grant(#KK.01.1.1.01.0010).
文摘Hepatocyte nuclear factor 1 alpha(HNF1A),hepatocyte nuclear factor 4 alpha(HNF4A),and forkhead box protein A2(FOXA2)are key transcription factors that regulate a complex gene network in the liver,cre-ating a regulatory transcriptional loop.The Encode and ChIP-Atlas databases identify the recognition sites of these transcription factors in many glycosyltransferase genes.Our in silico analysis of HNF1A,HNF4A.and FOXA2 binding to the ten candidate glyco-genes studied in this work confirms a significant enrich-ment of these transcription factors specifically in the liver.Our previous studies identified HNF1A as a master regulator of fucosylation,glycan branching,and galactosylation of plasma glycoproteins.Here,we aimed to functionally validate the role of the three transcription factors on downstream glyco-gene transcriptional expression and the possible effect on glycan phenotype.We used the state-of-the-art clus-tered regularly interspaced short palindromic repeats/dead Cas9(CRISPR/dCas9)molecular tool for the downregulation of the HNF1A,HNF4A,and FOXA2 genes in HepG2 cells-a human liver cancer cell line.The results show that the downregulation of all three genes individually and in pairs affects the transcrip-tional activity of many glyco-genes,although downregulation of glyco-genes was not always followed by an unambiguous change in the corresponding glycan structures.The effect is better seen as an overall change in the total HepG2 N-glycome,primarily due to the extension of biantennary glycans.We propose an alternative way to evaluate the N-glycome composition via estimating the overall complexity of the glycome by quantifying the number of monomers in each glycan structure.We also propose a model showing feedback loops with the mutual activation of HNF1A-FOXA2 and HNF4A-FOXA2 affecting glyco-genes and protein glycosylation in HepG2 cells.
文摘胃癌的发生是由正常胃黏膜经历慢性萎缩性胃炎、肠化生、异型增生直至胃癌发生的多阶段渐进性过程。其中肠化生是胃癌尤其是肠型胃癌重要的癌前病变。有研究证实,在肠化生及胃癌的发生过程中,性别决定区Y框蛋白2(SRY related HMG box-2,SOX2)、尾侧型同源转录因子2(caudal related homeobox transcription factor-2,CDX2)和肝细胞核因子(hepatocyte nuclear factor,HNF)4α均有参与,而且3个分子间存在明显相关性。因此,本文对目前SOX2、CDX2和HNF4α与胃癌的相关研究进展作一综述。
