Background:Colorectal cancer(CRC)is one of the most frequently diagnosed cancers.In many cases,the poor prognosis of advanced CRC is associated with resistance to treatment with chemotherapeutic drugs such as 5-Fluoro...Background:Colorectal cancer(CRC)is one of the most frequently diagnosed cancers.In many cases,the poor prognosis of advanced CRC is associated with resistance to treatment with chemotherapeutic drugs such as 5-Fluorouracil(5-FU).The epithelial-to-mesenchymal transition(EMT)and dysregulation in protein methylation are two mechanisms associated with chemoresistance in many cancers.This study looked into the effect of 5-FU dose escalation on EMT and protein methylation in CRC.Materials and Methods:HCT-116,Caco-2,and DLD-1 CRC cell lines were exposed to dose escalation treatment of 5-FU.The motility and invasive potentials of the cells before and after treatment with 5-FU were investigated through wound healing and invasion assays.This was followed by aWestern blot which analyzed the protein expressions of the epithelial marker E-cadherin,mesenchymal marker vimentin,and the EMT transcription factor(EMTTF),the snail family transcriptional repressor 1(Snail)in the parental and desensitized cells.Western blotting was also conducted to study the protein expressions of the protein methyltransferases(PMTs),Euchromatic histone lysine methyltransferase 2(EHMT2/G9A),protein arginine methyltransferase(PRMT5),and SET domain containing 7/9(SETD7/9)along with the global lysine and arginine methylation profiles.Results:The dose escalation method generated 5-FU desensitized CRC cells with distinct morphological features and increased tolerance to high doses of 5-FU.The 5-FU desensitized cells experienced a decrease in migration and invasion when compared to the parental cells.This was reflected in the observed reduction in E-cadherin,vimentin,and Snail in the desensitized cell lines.Additionally,the protein expressions of EHMT2/G9A,PRMT5,and SETD7/9 also decreased in the desensitized cells and global protein lysine and arginine methylation became dysregulated with 5-FU treatment.Conclusion:This study showed that continuous,dose-escalation treatment of 5-FU in CRC cells generated 5-FU desensitized cancer cells that seemed to be less aggressive than parental cells.展开更多
DNA methyltransferases(DNMTs)are an evolutionarily conserved family of DNA methylases,transferring a methyl group onto the fifth carbon of a cytosine residue.The mammalian DNMT family includes three major members that...DNA methyltransferases(DNMTs)are an evolutionarily conserved family of DNA methylases,transferring a methyl group onto the fifth carbon of a cytosine residue.The mammalian DNMT family includes three major members that have functional methylation activities,termed DNMT1,DNMT3A,and DNMT3B.DNMT3A and DNMT3B are responsible for methylation establishment,whereas DNMT1 maintains methylation during DNA replication.Accumulating evidence demonstrates that regulation of DNAmethylation by DNMTs is critical for normal hematopoiesis.Aberrant DNA methylation due to DNMT dysregulation and mutations is known as an important molecular event of hematological malignancies,such as DNMT3A mutations in acute myeloid leukemia.In this reviewwe first describe the basic methylation mechanisms of DNMTs and their functions in lymphocyte maturation and differentiation,We then discuss the current understanding of DNA methylation heterogeneity in leukemia and lymphoma to highlight the importance of studying DNA methylation targets.We also discuss DNMT mu-tations and pathogenic roles in human leukemia and lymphoma.We summarize the recent understanding of how DNMTs interact with transcription factors or cofactors to repress the expression of tumor suppressor genes.Firnally.we highlight current clinical studies using DNMT inhibitors for the treatment of these hematological malignancies.展开更多
Chemically modified cellular co-factors that provide function,such as immobilization or incorporation of fluorescent dyes,are valuable probes of biological activity.A convenient route to obtain S-adenosyl methionine（...Chemically modified cellular co-factors that provide function,such as immobilization or incorporation of fluorescent dyes,are valuable probes of biological activity.A convenient route to obtain S-adenosyl methionine（AdoMet） analogues modified at N-6 adenosine to feature a linker terminating in azide functionality is described herein.Subsequent decoration of such AdoMet analogues with guanidinium terminated linkers leads to novel potential bisubstrate inhibitors for protein arginine methyltrans-ferases, PRMTs.展开更多
DNA methyltransferases 1 (DNMT1) has been looked as crucial targets against various types of cancers. MD simulations have advanced to a point where the atomic level information of biological macromolecule (protein or ...DNA methyltransferases 1 (DNMT1) has been looked as crucial targets against various types of cancers. MD simulations have advanced to a point where the atomic level information of biological macromolecule (protein or DNA-protein or protein-protein) can easily be advantageous to predict the functionality. In this study we utilize xanthomicrol and galloyl compounds to investigate potential compounds for the inhibition of DNMT1, and the results of these two compounds are compared with drug decitabine. Xanthomicrol and galloyl are found to dock successfully within the active site of DNMT1. A comparison of the inhibitory potential of screened xanthomicrol inhibited DNMT1 approximately is identical with those of their corresponding drugs, decitabine. The stability of the DNMT1 with the best docked xanthomicrol, were further analysed in molecular dynamics (MD) simulation and compared with those of the respective drugs namely decitabine which revealed stabilization of these complexes within 300 ns of simulation with better stability of DNMT1.展开更多
Mesenchymal stem cells （MSCs） are characterized by their self-renewing capacity and differentiation potential into multiple tissues. Thus, management of the differentiation capacities of MSCs is important for MSC-ba...Mesenchymal stem cells （MSCs） are characterized by their self-renewing capacity and differentiation potential into multiple tissues. Thus, management of the differentiation capacities of MSCs is important for MSC-based regenerative medicine, such as craniofacial bone regeneration, and in new treatments for metabolic bone diseases, such as osteoporosis. In recent years, histone modification has been a growing topic in the field of MSC lineage specification, in which the Su（var）3-9, enhancer-of-zeste, trithorax （SET） domain-containing family and the Jumonji C （JmjC） domain-containing family represent the major histone lysine methyltransferases （KMTs） and histone lysine demethylases （KDMs）, respectively. In this review, we summarize the current understanding of the epigenetic mechanisms by which SET domain-containine KMTs and JmiC domain-containinlz KDMs balance the osteogenic and adipogenic differentiation of MSCs.展开更多
The limited regenerative capacity of neuronal cells requires tight orchestration of cell death and survival regulation in the context of longevity, age-associated diseases as well as during the development of the nerv...The limited regenerative capacity of neuronal cells requires tight orchestration of cell death and survival regulation in the context of longevity, age-associated diseases as well as during the development of the nervous system. Subordinate to genetic networks epigenetic mechanisms like DNA methylation and histone modifications are involved in the regulation of neuronal development, function and aging. DNA methylation by DNA methyltransferases （DNMTs）, mostly correlated with gene silencing, is a dynamic and reversible process. In addition to their canonical actions performing cytosine methylation, DNMTs influence gene expression by interactions with histone modifying enzymes or complexes increasing the complexity of epigenetic transcriptional networks. DNMTs are expressed in neuronal progenitors, post-mi- totic as well as adult neurons. In this review, we discuss the role and mode of actions of DNMTs including downstream networks in the regulation of neuronal survival in the developing and aging nervous system and its relevance for associated disorders.展开更多
Bisperoxo(1,10-phenanthroline) oxovanadate(BpV) can reportedly block the cell cycle. The present study examined whether BpV alters gene expression by affecting DNA methyltransferases(DNMTs), which would impact the cel...Bisperoxo(1,10-phenanthroline) oxovanadate(BpV) can reportedly block the cell cycle. The present study examined whether BpV alters gene expression by affecting DNA methyltransferases(DNMTs), which would impact the cell cycle. Immortalized mouse hippocampal neuronal precursor cells(HT_(22)) were treated with 0.3 or 3 μM BpV. Proliferation, morphology, and viability of HT_(22) cells were detected with an IncuCyte real-time video imaging system or inverted microscope and 3-(4,5-dimethylthiazol-2-yl)-5(3-carboxymethonyphenol)-2-(4-sulfophenyl)-2H-tetrazolium, respectively. mRNA and protein expression of DNMTs and p21 in HT_(22) cells was detected by real-time polymerase chain reaction and immunoblotting, respectively. In addition, DNMT activity was measured with an enzyme-linked immunosorbent assay. Effects of BpV on the cell cycle were analyzed using flow cytometry. Results demonstrated that treatment with 0.3 μM BpV did not affect cell proliferation, morphology, or viability; however, treatment with 3 μM BpV decreased cell viability, increased expression of both DNMT3B mRNA and protein, and inhibited the proliferation of HT_(22) cells; and 3 μM BpV also blocked the cell cycle and increased expression of the regulatory factor p21 by increasing DNMT expression in mouse hippocampal neurons.展开更多
DNA methylation is an important epigenetic regulation mechanism, which is catalyzed by DNA methyltransferases. In this study, eight DNA methyltransferase genes were identified in grape genome to analyze the selective ...DNA methylation is an important epigenetic regulation mechanism, which is catalyzed by DNA methyltransferases. In this study, eight DNA methyltransferase genes were identified in grape genome to analyze the selective pressure, gene expression and codon usage bias. The results showed grape DNA methyltransferase MET subfamily underwent relatively strong purifying selection during evolution, while chromomethylase CMT subfamily underwent positive selection during evolution. Under different abiotic(heat, drought or cold) stresses, the expression level of many grape DNA methyltransferase genes changed significantly. The expression level of these genes might be related with cis-regulatory elements of their promoters. The results of codon usage bias analysis showed that synonymous codon bias existed in grape DNA methyltransferase gene family, which might be affected by mutation pressure. These results laid a solid foundation for in-depth study of DNA methyltransferases in grape.展开更多
The reversible and precise temporal and spatial regulation of histone lysine methyltransferases(KMTs)is essential for epigenome homeostasis.The dysregulation of KMTs is associated with tumor initiation,metastasis,chem...The reversible and precise temporal and spatial regulation of histone lysine methyltransferases(KMTs)is essential for epigenome homeostasis.The dysregulation of KMTs is associated with tumor initiation,metastasis,chemoresistance,invasiveness,and the immune microenvironment.Therapeutically,their promising effects are being evaluated in diversified preclinical and clinical trials,demonstrating encouraging outcomes in multiple malignancies.In this review,we have updated recent understandings of KMTs'functions and the development of their targeted inhibitors.First,we provide an updated overview of the regulatory roles of several KMT activities in oncogenesis,tumor suppression,and immune regulation.In addition,we summarize the current targeting strategies in different cancer types and multiple ongoing clinical trials of combination therapies with KMT inhibitors.In summary,we endeavor to depict the regulation of KMT-mediated epigenetic landscape and provide potential epigenetic targets in the treatment of cancers.展开更多
Transfer RNA methyltransferases(tRNA MTases)catalyze site-specific methylation on tRNAs,a critical process that ensures the stability and functionality of tRNA molecules,thereby maintaining cellular homeostasis of tRN...Transfer RNA methyltransferases(tRNA MTases)catalyze site-specific methylation on tRNAs,a critical process that ensures the stability and functionality of tRNA molecules,thereby maintaining cellular homeostasis of tRNA methylation.Recent studies have illuminated the structural diversity,specific substrate recognition,and conserved catalytic mechanisms of tRNA MTases,revealing how their dysregulation contributes to various diseases,including cancers and neurodevelopmental disorders.This review integrates these advances,exploring the challenges of achieving precise substrate recognition and modification in the context of complex and specific tRNA modification landscape,while emphasizing the crucial role of tRNA MTases in disease pathogenesis.The identification of small-molecule inhibitors targeting specific tRNA MTases marks a promising step toward the development of novel therapies.With continued research into the broader biological functions and regulatory mechanisms of tRNA MTases,these insights hold great potential to drive clinical advancements and therapeutic innovations.展开更多
Histone lysine methyltransferases(HKMTs)deposit methyl groups onto lysine residues on histones and play important roles in regulating chromatin structure and gene expression.The structures and functions of HKMTs have ...Histone lysine methyltransferases(HKMTs)deposit methyl groups onto lysine residues on histones and play important roles in regulating chromatin structure and gene expression.The structures and functions of HKMTs have been extensively investigated in recent decades,significantly advancing our understanding of the dynamic regulation of histone methylation.Here,we review the recent progress in structural studies of representative HKMTs in complex with nucleosomes(H3K4,H3K27,H3K36,H3K79,and H4K20 methyltransferases),with emphasis on the molecular mechanisms of nucleosome recognition and trans-histone crosstalk by these HKMTs.These structural studies inform HKMTs'roles in tumorigenesis and provide the foundations for developing new therapeutic approachestargetingHKMTs incancers.展开更多
Background:Lung cancer remains the primary cause of mortality worldwide.Methylation modifications of eukaryotic messenger RNA(mRNA),recognized as one of the most prevalent chemical alterations,significantly impact the...Background:Lung cancer remains the primary cause of mortality worldwide.Methylation modifications of eukaryotic messenger RNA(mRNA),recognized as one of the most prevalent chemical alterations,significantly impact the stability,splicing,and translation of mRNA.Methyltransferase-like 21A(METTL21A)functions as a non-histone methyltransferase.The role of methylation-related compounds in the development of cancer has garnered increasing interest in recent years.Methods:The expression levels of METTL21A were assessed in 86 lung cancer samples and 78 adjacent non-cancerous tissues from Taizhou Hospital.Gene expression data were sourced from The Cancer Genome Atlas(TCGA)and Gene Expression Omnibus(GEO)databases.Multi-omics studies were conducted to examine the biological role of METTL21A within lung cancer.We thoroughly explored the potential functions and prognostic implications of METTL21A in this context.Results:An elevated expression of METTL21A was observed in lung cancer tissues.Furthermore,high levels of METTL21A expression correlate with various factors,including age,sex,race,tumor protein P53(TP53)mutations,cancer type,metastasis,and the pathological stage of lung cancer patients,indicating a relationship with poor prognosis.Additionally,METTL21A may affect lung cancer patient outcomes through distinct patterns of immune cell infiltration.Conclusion:METTL21A emerges as a promising candidate prognostic biomarker linked to immune invasion in lung cancer.展开更多
Objective To investigate the mechanism of in alleviating colonic mucosal inflammation in ten-eleven translocation(TET)protein 2 gene knockout(TET2^(-/-))mice with ulcerative colitis(UC)by regulating DNA methyltransfer...Objective To investigate the mechanism of in alleviating colonic mucosal inflammation in ten-eleven translocation(TET)protein 2 gene knockout(TET2^(-/-))mice with ulcerative colitis(UC)by regulating DNA methyltransferase(DNMT)and DNA hydroxymethylase.Methods Male specific pathogen-free(SPF)grade C57BL/6J wild-type(WT)mice(n=8)and TET2^(-/-)mice(n=20)were used to establish UC models by freely drinking 3%dextran sulfate sodium solution for 7 d.After UC model validation through histopathological examination in two mice from each type,the remaining mice were divided into four groups(n=6 in each group):WT model(WT+UC),TET2^(-/-)model(TET2^(-/-)+UC),TET2^(-/-)mild moxibustion(TET2^(-/-)+MM),and TET2^(-/-)electroacupuncture(TET2^(-/-)+EA)groups.TET2^(-/-)+MM group received mild moxibustion on Tianshu(ST25)and Qihai(CV6)for 10 min daily for 7 d.The TET2^(-/-)+EA group also applied electroacupuncture(1 mA,2/100 Hz)at the same acupoints for 10 min daily for 7 d.The disease activity index(DAI)scores of each group of mice were accessed daily.The colon lengths of mice in groups were measured following intervention.The pathological changes in the colon tissues were observed with hematoxylin and eosin(HE)staining.The concentrations of interleukin(IL)-6,C-C motif chemokine 17(CCL17),and C-X-C motif chemokine ligand 10(CXCL10)in serum were detected by enzyme-linked immunosorbent assay(ELISA).The expression of DNMT proteins(DNMT1,DNMT3A,and DNMT3B)in the colon tissues was detected by immunohistochemistry.The expression of 5-methylcytosine(5-mC),5-hydroxymethylcytosine(5-hmC),histone deacetylase 2(HDAC2),and DNA hydroxymethylase family proteins(TET 1 and TET3)was detected using immunofluorescence,which also determined the co-localization of TET1 and IL-6 protein.Results Compared with WT+UC group,TET2^(-/-)+UC group exhibited significantly higher DAI scores and shorter colon lengths(P<0.01).Both mild moxibustion and electroacupuncture significantly decreased DAI scores and ameliorated colon shortening in TET2^(-/-)mice(P<0.001).Histopathological scores of TET2^(-/-)+UC mice were significantly higher than those of WT+UC group(P<0.001)and were significantly reduced after both mild moxibustion and electroacupuncture interventions(P<0.001).Serum levels of IL-6,CCL17,and CXCL10 were significantly elevated in TET2^(-/-)+UC group compared with WT+UC group(P<0.001).Mild moxibustion significantly reduced IL-6,CCL17,and CXCL10 levels(P<0.001,P<0.001,and P<0.01,respectively),while electroacupuncture also significantly reduced IL-6,CCL17,and CXCL10 levels(P<0.05,P<0.01,and P<0.01,respectively).TET2^(-/-)+UC mice showed increased expression levels of DNMT1,DNMT3A,DNMT3B,and 5-mC(P<0.05,P<0.01 and P<0.001,respectively),with decreased expression levels of TET1,TET3,5-hmC,and HDAC2(P<0.001).Mild moxibustion significantly reduced DNMT1,DNMT3B,and 5-mC levels(P<0.05,P<0.01,and P<0.001,respectively),while increasing expression levels of TET1,TET3,5-hmC,and HDAC2(P<0.001,P<0.001,P<0.05,and P<0.001,respectively).Electroacupuncture significantly decreased 5-mC and DNMT3B levels(P<0.001 and P<0.01,respectively)and increased 5-hmC and HDAC2 levels(P<0.05 and P<0.001,respectively),but did not significantly affect TET1 and TET3 expression(P>0.05).Compared with TET2^(-/-)+MM group,TET2^(-/-)+EA group showed significantly higher 5-mC expression(P<0.001).TET2^(-/-)+UC group exhibited markedly increased IL-6 expression and higher co-localization of TET1 and IL-6 in mucosal epithelium,whereas minimal IL-6 expression was observed in the other groups.Conclusion Mild moxibustion and electroacupuncture significantly ameliorate colonic inflammation exacerbated by TET2 deficiency in UC mice via epigenetic modulation.Distinct mechanisms exist between the two interventions:mild moxibustion regulates both DNMT and hydroxymethylase,whereas electroacupuncture primarily affects DNMT.展开更多
BACKGROUND Gastric cancer(GC)is a malignant tumor originating from gastric mucosal epithelial cells that has high morbidity and mortality.microRNAs(miR)are important diagnostic markers and therapeutic targets in this ...BACKGROUND Gastric cancer(GC)is a malignant tumor originating from gastric mucosal epithelial cells that has high morbidity and mortality.microRNAs(miR)are important diagnostic markers and therapeutic targets in this disease.AIM To explore the mechanism of miR-125a-5p in the pathogenesis of GC.METHODS The expression levels of miR-125a-5p,SERPINE1 and DNMT1 in GC cells and tissues were detected by real-time polymerase chain reaction(PCR)and Western blotting.Methylation-specific PCR was used to detect the level of miR-125a-5p methylation.A cell counting kit 8 assay,scratch test,and a Transwell assay were performed to detect the proliferation,migration,and invasiveness of HGC27 cells,respectively.The expression of the epithelial mesenchymal transition(EMT)-related proteins E-cadherin,N-cadherin and vimentin in HGC27 cells was detected by Western blotting,while the expression of vimentin was detected by immunofluorescence.RESULTS This study revealed that miR-125a-5p was expressed at low levels in GC clinical samples and cells and that miR-125a-5p overexpression inhibited the proliferation,migration,invasiveness and EMT of GC cells.Mechanistically,miR-125a-5p can reduce GC cell proliferation,promote E-cadherin expression,inhibit N-cadherin and vimentin expression,and reduce the EMT of GC cells,thus constraining GC cells to a certain extent.Moreover,DNMT1 inhibited miR-125a-5p expression by increasing the methylation of the miR-125a-5p promoter,thereby promoting the expression of SERPINE1,which acts together with miR-125a-5p to exert antagonistic effects on GC.CONCLUSION Our study revealed that DNMT1 promoted SERPINE1 protein expression by inducing miR-125a-5p methylation,which led to the proliferation,migration and occurrence of EMT in GC cells.展开更多
Hypoxemia is a common pathological state characterized by low oxygen saturation in the blood.This condition compromises mucosal barrier integrity particularly in the gut and oral cavity.However,the mechanisms underlyi...Hypoxemia is a common pathological state characterized by low oxygen saturation in the blood.This condition compromises mucosal barrier integrity particularly in the gut and oral cavity.However,the mechanisms underlying this association remain unclear.This study used periodontitis as a model to investigate the role of platelet activation in oral mucosal immunopathology under hypoxic conditions.Hypoxia upregulated methyltransferase-like protein 4(METTL4)expression in platelets,resulting in N6-methyladenine modification of mitochondrial DNA(mtDNA).This modification impaired mitochondrial transcriptional factor A-dependent cytosolic mtDNA degradation,leading to cytosolic mtDNA accumulation.Excess cytosolic mt-DNA aberrantly activated the cGAS-STING pathway in platelets.This resulted in excessive platelet activation and neutrophil extracellular trap formation that ultimately exacerbated periodontitis.Targeting platelet METTL4 and its downstream pathways offers a potential strategy for managing oral mucosa immunopathology.Further research is needed to examine its broader implications for mucosal inflammation under hypoxic conditions.展开更多
BACKGROUND Centromere protein A(CENPA)exhibits an increased expression level in primary human rectal cancer tissues,but its role has not been investigated.AIM To clarify the specific role and mechanism of CENPA in rec...BACKGROUND Centromere protein A(CENPA)exhibits an increased expression level in primary human rectal cancer tissues,but its role has not been investigated.AIM To clarify the specific role and mechanism of CENPA in rectal cancer progression.METHODS CENPA protein expression in rectal cancer tissues and cell lines were detected.CENPA was overexpressed and knocked down in SW837 and SW480 cells,and proliferation,invasion,apoptosis and epithelial-mesenchymal transition(EMT)marker protein levels were examined.O6-methylguanine DNA methyltransferase(MGMT)promoter methylation was assessed with methylation-specific poly-merase chain reaction.Co-immunoprecipitation assay verified the interaction between MGMT and protein tyrosine phosphatase nonreceptor type 4(PTPN4).SW837 cells with CENPA knockdown were injected subcutaneously into mice,and tumor growth was examined.RESULTS CENPA was upregulated in rectal cancer tissues and cell lines.CENPA overex-pression promoted proliferation,invasion and EMT,and inhibited apoptosis in rectal cancer cells.Whereas CENPA knockdown showed the opposite results.Moreover,CENPA inhibited MGMT expression by promoting DNA methyltrans-ferase 1-mediated MGMT promoter methylation.MGMT knockdown abolished the CENPA knockdown-mediated inhibition of rectal cancer cell progression.MGMT increased PTPN4 protein stability by inhibiting PTPN4 ubiquitination degradation via competing with ubiquitin-conjugating enzyme E2O for interacting with PTPN4.PTPN4 knockdown abolished the inhibitory effects of MGMT overexpression on rectal cancer cell progression.Moreover,CENPA knockdown inhibited xenograft tumor growth in vivo.CONCLUSION CENPA knockdown inhibited rectal cancer cell growth and attenuated xenograft tumor growth through regulating the MGMT/PTPN4 axis.展开更多
Objective To investigate the effects of calprotectin(S100A8/A9)on the biological activity of acute myeloid leukemia(AML)cells harboring a DNA methyltransferase 3A(DNMT3A)mutation and to explore the underlying molecula...Objective To investigate the effects of calprotectin(S100A8/A9)on the biological activity of acute myeloid leukemia(AML)cells harboring a DNA methyltransferase 3A(DNMT3A)mutation and to explore the underlying molecular mechanisms involved.Methods AML monoclonal cell lines harboring the DNMT3A^(R882H) mutation were generated via lentiviral transduction and limiting dilution.RNA sequencing was used for differential gene expression analysis,followed by bioinformatic pathway enrichment and gene correlation analyses.The biological effects of paquinimod,a selective S100A8/A9 inhibitor,on DNMT3A^(R882H) AML cells were assessed via Cell Counting Kit(CCK-8)proliferation assays,Annexin V/PI staining,cell cycle analysis,cell adhesion assays,and transwell migration assays.Results Differential gene expression analysis revealed 442 upregulated and 535 downregulated genes in DNMT3A-mutated(DNMT3A^(mut))cells compared with those in DNMT3A wild-type(DNMT3A^(wt))cells,with the S100A8/A9 complex recurrently enriched in Reactome pathway analysis.Compared with healthy controls,patients with AML presented increased expression of S100A8 and S100A9 and increased expression of DNMT3A^(mut) cells relative to DNMT3A^(wt) cells,which was correlated with poor prognosis in patients with AML.There were no notable differences in proliferation among the DNMT3A^(mut),DNMT3A^(wt),and empty vector cells under normal or starvation conditions.However,paquinimod treatment notably inhibited the proliferation,migration,and adhesion of DNMT3A^(mut) AML cells in a dose-dependent manner,causing G0/G1 cell cycle arrest,whereas no significant effects on apoptosis were observed.Paquinimod also downregulated key adhesion molecules,including intercellular adhesion molecule 1(ICAM-1),vascular cell adhesion molecule 1(VCAM-1),monocyte chemoattractant protein-1(MCP-1),and matrix metalloproteinase-2(MMP-2).Additionally,S100A8 and S100A9 expression was upregulated in a dose-dependent manner in response to cytarabine treatment.Conclusion Elevated S100A8/A9 expression contributes to the abnormal proliferation,migration,adhesion,and chemoresistance of DNMT3A^(mut) AML cells.Targeting S100A8/A9 alone or in combination with other treatments represents a promising therapeutic strategy for DNMT3A^(mut) AML.展开更多
In this editorial,we highlight the study by Xiao et al.Despite progress in the management of diabetic foot ulcers(DFUs),impaired wound healing remains a significant clinical challenge.Recent studies have highlighted t...In this editorial,we highlight the study by Xiao et al.Despite progress in the management of diabetic foot ulcers(DFUs),impaired wound healing remains a significant clinical challenge.Recent studies have highlighted the critical role of epigenetic modifications in diabetic wound healing,with particular emphasis on DNA and RNA methylation pathways.This editorial discusses the findings of Xiao et al,who identified the Wilms tumor 1-associated protein(WTAP)-DNA methyltransferase 1(DNMT1)axis as a pivotal regulator of endothelial dys-function in DFUs.WTAP,a regulatory subunit of N6-methyladenosine(m6A)methyltransferase,is upregulated under high-glucose conditions and drives the excessive expression of DNMT1 via m6A modification.This contributes to im-paired angiogenesis,reduced cell viability,and delayed wound closure.WTAP knockdown restored endothelial function and significantly improved wound healing in a diabetic mouse model.Furthermore,DNMT1 overexpression ab-rogated the benefits of WTAP suppression,confirming its downstream effector role.Thus,targeting the WTAP-DNMT1 axis provides a new avenue for DFU management.Moreover,epigenetic interventions that modulate both the m6A and RNA methylation pathways could restore endothelial function and enhance tissue repair in patients with diabetes.展开更多
基金supported through the Faculty of Medicine and Surgery Award 2021 University of Malta(awarded to K.F).
文摘Background:Colorectal cancer(CRC)is one of the most frequently diagnosed cancers.In many cases,the poor prognosis of advanced CRC is associated with resistance to treatment with chemotherapeutic drugs such as 5-Fluorouracil(5-FU).The epithelial-to-mesenchymal transition(EMT)and dysregulation in protein methylation are two mechanisms associated with chemoresistance in many cancers.This study looked into the effect of 5-FU dose escalation on EMT and protein methylation in CRC.Materials and Methods:HCT-116,Caco-2,and DLD-1 CRC cell lines were exposed to dose escalation treatment of 5-FU.The motility and invasive potentials of the cells before and after treatment with 5-FU were investigated through wound healing and invasion assays.This was followed by aWestern blot which analyzed the protein expressions of the epithelial marker E-cadherin,mesenchymal marker vimentin,and the EMT transcription factor(EMTTF),the snail family transcriptional repressor 1(Snail)in the parental and desensitized cells.Western blotting was also conducted to study the protein expressions of the protein methyltransferases(PMTs),Euchromatic histone lysine methyltransferase 2(EHMT2/G9A),protein arginine methyltransferase(PRMT5),and SET domain containing 7/9(SETD7/9)along with the global lysine and arginine methylation profiles.Results:The dose escalation method generated 5-FU desensitized CRC cells with distinct morphological features and increased tolerance to high doses of 5-FU.The 5-FU desensitized cells experienced a decrease in migration and invasion when compared to the parental cells.This was reflected in the observed reduction in E-cadherin,vimentin,and Snail in the desensitized cell lines.Additionally,the protein expressions of EHMT2/G9A,PRMT5,and SETD7/9 also decreased in the desensitized cells and global protein lysine and arginine methylation became dysregulated with 5-FU treatment.Conclusion:This study showed that continuous,dose-escalation treatment of 5-FU in CRC cells generated 5-FU desensitized cancer cells that seemed to be less aggressive than parental cells.
基金the National lnstitutes of Health/National Cancer Institute(NlH/NCT)grant RO1 CA187299(L.R.)。
文摘DNA methyltransferases(DNMTs)are an evolutionarily conserved family of DNA methylases,transferring a methyl group onto the fifth carbon of a cytosine residue.The mammalian DNMT family includes three major members that have functional methylation activities,termed DNMT1,DNMT3A,and DNMT3B.DNMT3A and DNMT3B are responsible for methylation establishment,whereas DNMT1 maintains methylation during DNA replication.Accumulating evidence demonstrates that regulation of DNAmethylation by DNMTs is critical for normal hematopoiesis.Aberrant DNA methylation due to DNMT dysregulation and mutations is known as an important molecular event of hematological malignancies,such as DNMT3A mutations in acute myeloid leukemia.In this reviewwe first describe the basic methylation mechanisms of DNMTs and their functions in lymphocyte maturation and differentiation,We then discuss the current understanding of DNA methylation heterogeneity in leukemia and lymphoma to highlight the importance of studying DNA methylation targets.We also discuss DNMT mu-tations and pathogenic roles in human leukemia and lymphoma.We summarize the recent understanding of how DNMTs interact with transcription factors or cofactors to repress the expression of tumor suppressor genes.Firnally.we highlight current clinical studies using DNMT inhibitors for the treatment of these hematological malignancies.
基金financially supported by the Medical Research Council Grant(No.G0700840)
文摘Chemically modified cellular co-factors that provide function,such as immobilization or incorporation of fluorescent dyes,are valuable probes of biological activity.A convenient route to obtain S-adenosyl methionine（AdoMet） analogues modified at N-6 adenosine to feature a linker terminating in azide functionality is described herein.Subsequent decoration of such AdoMet analogues with guanidinium terminated linkers leads to novel potential bisubstrate inhibitors for protein arginine methyltrans-ferases, PRMTs.
文摘DNA methyltransferases 1 (DNMT1) has been looked as crucial targets against various types of cancers. MD simulations have advanced to a point where the atomic level information of biological macromolecule (protein or DNA-protein or protein-protein) can easily be advantageous to predict the functionality. In this study we utilize xanthomicrol and galloyl compounds to investigate potential compounds for the inhibition of DNMT1, and the results of these two compounds are compared with drug decitabine. Xanthomicrol and galloyl are found to dock successfully within the active site of DNMT1. A comparison of the inhibitory potential of screened xanthomicrol inhibited DNMT1 approximately is identical with those of their corresponding drugs, decitabine. The stability of the DNMT1 with the best docked xanthomicrol, were further analysed in molecular dynamics (MD) simulation and compared with those of the respective drugs namely decitabine which revealed stabilization of these complexes within 300 ns of simulation with better stability of DNMT1.
基金supported by the National Institute of Dental and Craniofacial Research grants, K08DE024603-02, DE019412, and DE01651a grant from 111 Project of MOE, Chinasupported by Open Fund of State Key Laboratory of Oral Diseases, Sichuan University
文摘Mesenchymal stem cells （MSCs） are characterized by their self-renewing capacity and differentiation potential into multiple tissues. Thus, management of the differentiation capacities of MSCs is important for MSC-based regenerative medicine, such as craniofacial bone regeneration, and in new treatments for metabolic bone diseases, such as osteoporosis. In recent years, histone modification has been a growing topic in the field of MSC lineage specification, in which the Su（var）3-9, enhancer-of-zeste, trithorax （SET） domain-containing family and the Jumonji C （JmjC） domain-containing family represent the major histone lysine methyltransferases （KMTs） and histone lysine demethylases （KDMs）, respectively. In this review, we summarize the current understanding of the epigenetic mechanisms by which SET domain-containine KMTs and JmiC domain-containinlz KDMs balance the osteogenic and adipogenic differentiation of MSCs.
文摘The limited regenerative capacity of neuronal cells requires tight orchestration of cell death and survival regulation in the context of longevity, age-associated diseases as well as during the development of the nervous system. Subordinate to genetic networks epigenetic mechanisms like DNA methylation and histone modifications are involved in the regulation of neuronal development, function and aging. DNA methylation by DNA methyltransferases （DNMTs）, mostly correlated with gene silencing, is a dynamic and reversible process. In addition to their canonical actions performing cytosine methylation, DNMTs influence gene expression by interactions with histone modifying enzymes or complexes increasing the complexity of epigenetic transcriptional networks. DNMTs are expressed in neuronal progenitors, post-mi- totic as well as adult neurons. In this review, we discuss the role and mode of actions of DNMTs including downstream networks in the regulation of neuronal survival in the developing and aging nervous system and its relevance for associated disorders.
基金supported by the National Natural Science Foundation of China,No.81160244,81360316,81460283,81660307(all to GS)the Inner Mongolia Science Foundation of China,No.2018LH08078(to GS),2016MS(LH)0307(to SYJ)+4 种基金the Baotou Health Foundation,China,No.WSJJ2016008(to SYJ)the Inner Mongolia Educational Research Foundation of China,No.NJZY207(to GS),NJZY17243(to SCY),NJZY17250(to XLL),NJZY17251(to SYJ)the Baotou Medical College Foundation of China,No.BYJJ-DF201602,BYJJ-YF201615,BSJJ201617,BYJJ-QM201633,BYJJ-QM201656,BYJJ201502(to GS)the Science and Technology Planning Project of Baotou of China,No.CX2017-5(to GS)the National Key R&D Program of China,No.2017YFC1308405(to GS)
文摘Bisperoxo(1,10-phenanthroline) oxovanadate(BpV) can reportedly block the cell cycle. The present study examined whether BpV alters gene expression by affecting DNA methyltransferases(DNMTs), which would impact the cell cycle. Immortalized mouse hippocampal neuronal precursor cells(HT_(22)) were treated with 0.3 or 3 μM BpV. Proliferation, morphology, and viability of HT_(22) cells were detected with an IncuCyte real-time video imaging system or inverted microscope and 3-(4,5-dimethylthiazol-2-yl)-5(3-carboxymethonyphenol)-2-(4-sulfophenyl)-2H-tetrazolium, respectively. mRNA and protein expression of DNMTs and p21 in HT_(22) cells was detected by real-time polymerase chain reaction and immunoblotting, respectively. In addition, DNMT activity was measured with an enzyme-linked immunosorbent assay. Effects of BpV on the cell cycle were analyzed using flow cytometry. Results demonstrated that treatment with 0.3 μM BpV did not affect cell proliferation, morphology, or viability; however, treatment with 3 μM BpV decreased cell viability, increased expression of both DNMT3B mRNA and protein, and inhibited the proliferation of HT_(22) cells; and 3 μM BpV also blocked the cell cycle and increased expression of the regulatory factor p21 by increasing DNMT expression in mouse hippocampal neurons.
基金Supported by Major Agricultural Application Technology Innovation Project of Shandong Province"Research and Application of Precision Control of Maturation and Product Innovation of Featured Brewing Grape"Major Agricultural Application Technology Innovation Project of Shandong Province"Development of Landmark Wines and Integrated Application of Key Technologies in Shandong Province"Agricultural Scientific and Technological Innovation Project of Shandong Academy of Agricultural Sciences(CXGC2016D01)
文摘DNA methylation is an important epigenetic regulation mechanism, which is catalyzed by DNA methyltransferases. In this study, eight DNA methyltransferase genes were identified in grape genome to analyze the selective pressure, gene expression and codon usage bias. The results showed grape DNA methyltransferase MET subfamily underwent relatively strong purifying selection during evolution, while chromomethylase CMT subfamily underwent positive selection during evolution. Under different abiotic(heat, drought or cold) stresses, the expression level of many grape DNA methyltransferase genes changed significantly. The expression level of these genes might be related with cis-regulatory elements of their promoters. The results of codon usage bias analysis showed that synonymous codon bias existed in grape DNA methyltransferase gene family, which might be affected by mutation pressure. These results laid a solid foundation for in-depth study of DNA methyltransferases in grape.
基金the Science and Technology Commission of Shanghai,China(Grant Nos.:20DZ2270800 and 19JC1410200)Innovative Research Team of High-Level Local Universities in Shanghai,China(Grant No.:SHSMU-ZDCX20210900)the National Natural Science Foundation of China(Grant No.:82073889).
文摘The reversible and precise temporal and spatial regulation of histone lysine methyltransferases(KMTs)is essential for epigenome homeostasis.The dysregulation of KMTs is associated with tumor initiation,metastasis,chemoresistance,invasiveness,and the immune microenvironment.Therapeutically,their promising effects are being evaluated in diversified preclinical and clinical trials,demonstrating encouraging outcomes in multiple malignancies.In this review,we have updated recent understandings of KMTs'functions and the development of their targeted inhibitors.First,we provide an updated overview of the regulatory roles of several KMT activities in oncogenesis,tumor suppression,and immune regulation.In addition,we summarize the current targeting strategies in different cancer types and multiple ongoing clinical trials of combination therapies with KMT inhibitors.In summary,we endeavor to depict the regulation of KMT-mediated epigenetic landscape and provide potential epigenetic targets in the treatment of cancers.
基金supported by the National Natural Science Foundation of China(32401073)。
文摘Transfer RNA methyltransferases(tRNA MTases)catalyze site-specific methylation on tRNAs,a critical process that ensures the stability and functionality of tRNA molecules,thereby maintaining cellular homeostasis of tRNA methylation.Recent studies have illuminated the structural diversity,specific substrate recognition,and conserved catalytic mechanisms of tRNA MTases,revealing how their dysregulation contributes to various diseases,including cancers and neurodevelopmental disorders.This review integrates these advances,exploring the challenges of achieving precise substrate recognition and modification in the context of complex and specific tRNA modification landscape,while emphasizing the crucial role of tRNA MTases in disease pathogenesis.The identification of small-molecule inhibitors targeting specific tRNA MTases marks a promising step toward the development of novel therapies.With continued research into the broader biological functions and regulatory mechanisms of tRNA MTases,these insights hold great potential to drive clinical advancements and therapeutic innovations.
基金supported by grants from the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB37010303 to Y.C.)the National Natural Science Foundation of China(31670748,31970576 to Y.C.,and 32071195 and 31900934 to Y.L.)+1 种基金the Young Elite Scientist Sponsorship Program by Chinese Association for Science and Technology(YESS20170198 to Y.L.)the National Postdoctoral Program for Innovative Talents(Bx201700263 to Y.L.).
文摘Histone lysine methyltransferases(HKMTs)deposit methyl groups onto lysine residues on histones and play important roles in regulating chromatin structure and gene expression.The structures and functions of HKMTs have been extensively investigated in recent decades,significantly advancing our understanding of the dynamic regulation of histone methylation.Here,we review the recent progress in structural studies of representative HKMTs in complex with nucleosomes(H3K4,H3K27,H3K36,H3K79,and H4K20 methyltransferases),with emphasis on the molecular mechanisms of nucleosome recognition and trans-histone crosstalk by these HKMTs.These structural studies inform HKMTs'roles in tumorigenesis and provide the foundations for developing new therapeutic approachestargetingHKMTs incancers.
基金supported by the Shenzhen Municipal Government of China(No.JCYJ20180507184647104)the Natural Science Foundation of Guangdong Province(Nos.2021A1515011426,2023A1515012585)。
文摘Background:Lung cancer remains the primary cause of mortality worldwide.Methylation modifications of eukaryotic messenger RNA(mRNA),recognized as one of the most prevalent chemical alterations,significantly impact the stability,splicing,and translation of mRNA.Methyltransferase-like 21A(METTL21A)functions as a non-histone methyltransferase.The role of methylation-related compounds in the development of cancer has garnered increasing interest in recent years.Methods:The expression levels of METTL21A were assessed in 86 lung cancer samples and 78 adjacent non-cancerous tissues from Taizhou Hospital.Gene expression data were sourced from The Cancer Genome Atlas(TCGA)and Gene Expression Omnibus(GEO)databases.Multi-omics studies were conducted to examine the biological role of METTL21A within lung cancer.We thoroughly explored the potential functions and prognostic implications of METTL21A in this context.Results:An elevated expression of METTL21A was observed in lung cancer tissues.Furthermore,high levels of METTL21A expression correlate with various factors,including age,sex,race,tumor protein P53(TP53)mutations,cancer type,metastasis,and the pathological stage of lung cancer patients,indicating a relationship with poor prognosis.Additionally,METTL21A may affect lung cancer patient outcomes through distinct patterns of immune cell infiltration.Conclusion:METTL21A emerges as a promising candidate prognostic biomarker linked to immune invasion in lung cancer.
基金National Natural Science Foundation of China(82274641,81873372,and 82105012).
文摘Objective To investigate the mechanism of in alleviating colonic mucosal inflammation in ten-eleven translocation(TET)protein 2 gene knockout(TET2^(-/-))mice with ulcerative colitis(UC)by regulating DNA methyltransferase(DNMT)and DNA hydroxymethylase.Methods Male specific pathogen-free(SPF)grade C57BL/6J wild-type(WT)mice(n=8)and TET2^(-/-)mice(n=20)were used to establish UC models by freely drinking 3%dextran sulfate sodium solution for 7 d.After UC model validation through histopathological examination in two mice from each type,the remaining mice were divided into four groups(n=6 in each group):WT model(WT+UC),TET2^(-/-)model(TET2^(-/-)+UC),TET2^(-/-)mild moxibustion(TET2^(-/-)+MM),and TET2^(-/-)electroacupuncture(TET2^(-/-)+EA)groups.TET2^(-/-)+MM group received mild moxibustion on Tianshu(ST25)and Qihai(CV6)for 10 min daily for 7 d.The TET2^(-/-)+EA group also applied electroacupuncture(1 mA,2/100 Hz)at the same acupoints for 10 min daily for 7 d.The disease activity index(DAI)scores of each group of mice were accessed daily.The colon lengths of mice in groups were measured following intervention.The pathological changes in the colon tissues were observed with hematoxylin and eosin(HE)staining.The concentrations of interleukin(IL)-6,C-C motif chemokine 17(CCL17),and C-X-C motif chemokine ligand 10(CXCL10)in serum were detected by enzyme-linked immunosorbent assay(ELISA).The expression of DNMT proteins(DNMT1,DNMT3A,and DNMT3B)in the colon tissues was detected by immunohistochemistry.The expression of 5-methylcytosine(5-mC),5-hydroxymethylcytosine(5-hmC),histone deacetylase 2(HDAC2),and DNA hydroxymethylase family proteins(TET 1 and TET3)was detected using immunofluorescence,which also determined the co-localization of TET1 and IL-6 protein.Results Compared with WT+UC group,TET2^(-/-)+UC group exhibited significantly higher DAI scores and shorter colon lengths(P<0.01).Both mild moxibustion and electroacupuncture significantly decreased DAI scores and ameliorated colon shortening in TET2^(-/-)mice(P<0.001).Histopathological scores of TET2^(-/-)+UC mice were significantly higher than those of WT+UC group(P<0.001)and were significantly reduced after both mild moxibustion and electroacupuncture interventions(P<0.001).Serum levels of IL-6,CCL17,and CXCL10 were significantly elevated in TET2^(-/-)+UC group compared with WT+UC group(P<0.001).Mild moxibustion significantly reduced IL-6,CCL17,and CXCL10 levels(P<0.001,P<0.001,and P<0.01,respectively),while electroacupuncture also significantly reduced IL-6,CCL17,and CXCL10 levels(P<0.05,P<0.01,and P<0.01,respectively).TET2^(-/-)+UC mice showed increased expression levels of DNMT1,DNMT3A,DNMT3B,and 5-mC(P<0.05,P<0.01 and P<0.001,respectively),with decreased expression levels of TET1,TET3,5-hmC,and HDAC2(P<0.001).Mild moxibustion significantly reduced DNMT1,DNMT3B,and 5-mC levels(P<0.05,P<0.01,and P<0.001,respectively),while increasing expression levels of TET1,TET3,5-hmC,and HDAC2(P<0.001,P<0.001,P<0.05,and P<0.001,respectively).Electroacupuncture significantly decreased 5-mC and DNMT3B levels(P<0.001 and P<0.01,respectively)and increased 5-hmC and HDAC2 levels(P<0.05 and P<0.001,respectively),but did not significantly affect TET1 and TET3 expression(P>0.05).Compared with TET2^(-/-)+MM group,TET2^(-/-)+EA group showed significantly higher 5-mC expression(P<0.001).TET2^(-/-)+UC group exhibited markedly increased IL-6 expression and higher co-localization of TET1 and IL-6 in mucosal epithelium,whereas minimal IL-6 expression was observed in the other groups.Conclusion Mild moxibustion and electroacupuncture significantly ameliorate colonic inflammation exacerbated by TET2 deficiency in UC mice via epigenetic modulation.Distinct mechanisms exist between the two interventions:mild moxibustion regulates both DNMT and hydroxymethylase,whereas electroacupuncture primarily affects DNMT.
基金the Research Program of the Science and Technology Department of Yunnan Province,No.202101AY070001-204.
文摘BACKGROUND Gastric cancer(GC)is a malignant tumor originating from gastric mucosal epithelial cells that has high morbidity and mortality.microRNAs(miR)are important diagnostic markers and therapeutic targets in this disease.AIM To explore the mechanism of miR-125a-5p in the pathogenesis of GC.METHODS The expression levels of miR-125a-5p,SERPINE1 and DNMT1 in GC cells and tissues were detected by real-time polymerase chain reaction(PCR)and Western blotting.Methylation-specific PCR was used to detect the level of miR-125a-5p methylation.A cell counting kit 8 assay,scratch test,and a Transwell assay were performed to detect the proliferation,migration,and invasiveness of HGC27 cells,respectively.The expression of the epithelial mesenchymal transition(EMT)-related proteins E-cadherin,N-cadherin and vimentin in HGC27 cells was detected by Western blotting,while the expression of vimentin was detected by immunofluorescence.RESULTS This study revealed that miR-125a-5p was expressed at low levels in GC clinical samples and cells and that miR-125a-5p overexpression inhibited the proliferation,migration,invasiveness and EMT of GC cells.Mechanistically,miR-125a-5p can reduce GC cell proliferation,promote E-cadherin expression,inhibit N-cadherin and vimentin expression,and reduce the EMT of GC cells,thus constraining GC cells to a certain extent.Moreover,DNMT1 inhibited miR-125a-5p expression by increasing the methylation of the miR-125a-5p promoter,thereby promoting the expression of SERPINE1,which acts together with miR-125a-5p to exert antagonistic effects on GC.CONCLUSION Our study revealed that DNMT1 promoted SERPINE1 protein expression by inducing miR-125a-5p methylation,which led to the proliferation,migration and occurrence of EMT in GC cells.
基金supported by the National Natural Science Foundation of China(82325012)the Youth Fund of the National Natural Science Foundation of China(82301043)+1 种基金the Natural Science Basic Research Program of Shaanxi (Program No.2024JC-YBQN-0980)the Shaanxi Key Scientific and Technological Innovation Team(2020TD-033).
文摘Hypoxemia is a common pathological state characterized by low oxygen saturation in the blood.This condition compromises mucosal barrier integrity particularly in the gut and oral cavity.However,the mechanisms underlying this association remain unclear.This study used periodontitis as a model to investigate the role of platelet activation in oral mucosal immunopathology under hypoxic conditions.Hypoxia upregulated methyltransferase-like protein 4(METTL4)expression in platelets,resulting in N6-methyladenine modification of mitochondrial DNA(mtDNA).This modification impaired mitochondrial transcriptional factor A-dependent cytosolic mtDNA degradation,leading to cytosolic mtDNA accumulation.Excess cytosolic mt-DNA aberrantly activated the cGAS-STING pathway in platelets.This resulted in excessive platelet activation and neutrophil extracellular trap formation that ultimately exacerbated periodontitis.Targeting platelet METTL4 and its downstream pathways offers a potential strategy for managing oral mucosa immunopathology.Further research is needed to examine its broader implications for mucosal inflammation under hypoxic conditions.
基金This study was reviewed and approved by the Ethic Committee of Medical College of Henan Vocational University of Science and Technology(Approval No.HVUYL414101416920231017001)all participants signed a written informed consent.
文摘BACKGROUND Centromere protein A(CENPA)exhibits an increased expression level in primary human rectal cancer tissues,but its role has not been investigated.AIM To clarify the specific role and mechanism of CENPA in rectal cancer progression.METHODS CENPA protein expression in rectal cancer tissues and cell lines were detected.CENPA was overexpressed and knocked down in SW837 and SW480 cells,and proliferation,invasion,apoptosis and epithelial-mesenchymal transition(EMT)marker protein levels were examined.O6-methylguanine DNA methyltransferase(MGMT)promoter methylation was assessed with methylation-specific poly-merase chain reaction.Co-immunoprecipitation assay verified the interaction between MGMT and protein tyrosine phosphatase nonreceptor type 4(PTPN4).SW837 cells with CENPA knockdown were injected subcutaneously into mice,and tumor growth was examined.RESULTS CENPA was upregulated in rectal cancer tissues and cell lines.CENPA overex-pression promoted proliferation,invasion and EMT,and inhibited apoptosis in rectal cancer cells.Whereas CENPA knockdown showed the opposite results.Moreover,CENPA inhibited MGMT expression by promoting DNA methyltrans-ferase 1-mediated MGMT promoter methylation.MGMT knockdown abolished the CENPA knockdown-mediated inhibition of rectal cancer cell progression.MGMT increased PTPN4 protein stability by inhibiting PTPN4 ubiquitination degradation via competing with ubiquitin-conjugating enzyme E2O for interacting with PTPN4.PTPN4 knockdown abolished the inhibitory effects of MGMT overexpression on rectal cancer cell progression.Moreover,CENPA knockdown inhibited xenograft tumor growth in vivo.CONCLUSION CENPA knockdown inhibited rectal cancer cell growth and attenuated xenograft tumor growth through regulating the MGMT/PTPN4 axis.
基金funded by the National Natural Science Foundation of China(Grant No.82270177)the China Medicine Education Association 2024 Medical Science and Technology Research Project(Grant No.2024KTZ035).
文摘Objective To investigate the effects of calprotectin(S100A8/A9)on the biological activity of acute myeloid leukemia(AML)cells harboring a DNA methyltransferase 3A(DNMT3A)mutation and to explore the underlying molecular mechanisms involved.Methods AML monoclonal cell lines harboring the DNMT3A^(R882H) mutation were generated via lentiviral transduction and limiting dilution.RNA sequencing was used for differential gene expression analysis,followed by bioinformatic pathway enrichment and gene correlation analyses.The biological effects of paquinimod,a selective S100A8/A9 inhibitor,on DNMT3A^(R882H) AML cells were assessed via Cell Counting Kit(CCK-8)proliferation assays,Annexin V/PI staining,cell cycle analysis,cell adhesion assays,and transwell migration assays.Results Differential gene expression analysis revealed 442 upregulated and 535 downregulated genes in DNMT3A-mutated(DNMT3A^(mut))cells compared with those in DNMT3A wild-type(DNMT3A^(wt))cells,with the S100A8/A9 complex recurrently enriched in Reactome pathway analysis.Compared with healthy controls,patients with AML presented increased expression of S100A8 and S100A9 and increased expression of DNMT3A^(mut) cells relative to DNMT3A^(wt) cells,which was correlated with poor prognosis in patients with AML.There were no notable differences in proliferation among the DNMT3A^(mut),DNMT3A^(wt),and empty vector cells under normal or starvation conditions.However,paquinimod treatment notably inhibited the proliferation,migration,and adhesion of DNMT3A^(mut) AML cells in a dose-dependent manner,causing G0/G1 cell cycle arrest,whereas no significant effects on apoptosis were observed.Paquinimod also downregulated key adhesion molecules,including intercellular adhesion molecule 1(ICAM-1),vascular cell adhesion molecule 1(VCAM-1),monocyte chemoattractant protein-1(MCP-1),and matrix metalloproteinase-2(MMP-2).Additionally,S100A8 and S100A9 expression was upregulated in a dose-dependent manner in response to cytarabine treatment.Conclusion Elevated S100A8/A9 expression contributes to the abnormal proliferation,migration,adhesion,and chemoresistance of DNMT3A^(mut) AML cells.Targeting S100A8/A9 alone or in combination with other treatments represents a promising therapeutic strategy for DNMT3A^(mut) AML.
基金Supported by the Kuwait Foundation for the Advancement of Sciences and Dasman Diabetes Institute,No.RACB-2021-007.
文摘In this editorial,we highlight the study by Xiao et al.Despite progress in the management of diabetic foot ulcers(DFUs),impaired wound healing remains a significant clinical challenge.Recent studies have highlighted the critical role of epigenetic modifications in diabetic wound healing,with particular emphasis on DNA and RNA methylation pathways.This editorial discusses the findings of Xiao et al,who identified the Wilms tumor 1-associated protein(WTAP)-DNA methyltransferase 1(DNMT1)axis as a pivotal regulator of endothelial dys-function in DFUs.WTAP,a regulatory subunit of N6-methyladenosine(m6A)methyltransferase,is upregulated under high-glucose conditions and drives the excessive expression of DNMT1 via m6A modification.This contributes to im-paired angiogenesis,reduced cell viability,and delayed wound closure.WTAP knockdown restored endothelial function and significantly improved wound healing in a diabetic mouse model.Furthermore,DNMT1 overexpression ab-rogated the benefits of WTAP suppression,confirming its downstream effector role.Thus,targeting the WTAP-DNMT1 axis provides a new avenue for DFU management.Moreover,epigenetic interventions that modulate both the m6A and RNA methylation pathways could restore endothelial function and enhance tissue repair in patients with diabetes.
