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1.
Methods Cell Biol ; 186: 131-150, 2024.
Article in English | MEDLINE | ID: mdl-38705597

ABSTRACT

Hypomethylating therapies using decitabine or azacitidine are actively investigated to treat acute myeloid leukemia, myelodysplastic syndromes, as maintenance therapy after allogenic stem cell transplant and hemoglobinopathies. The therapeutic mechanism is to de-repress genes that have been turned off through oncogenesis or development via methylation. The therapy can be non-cytotoxic at low dosage, sparing healthy stem cells and operating on committed precursors. Because the methods of determining maximum tolerated dose are not well suited to this paradigm, and because the mechanism of action, which is depletion of DNA methylase 1 (DNMT1), is complex and dependent on passing through a cell cycle, a pharmacodynamic assay that measures DNMT1 can inform clinical trials aimed at establishing and improving therapy. Herein, we provide an assay that measures DNMT1 relative levels in circulating T cells of peripheral blood.


Subject(s)
Azacitidine , DNA (Cytosine-5-)-Methyltransferase 1 , DNA Methylation , Decitabine , Azacitidine/pharmacology , Humans , Decitabine/pharmacology , DNA Methylation/drug effects , DNA (Cytosine-5-)-Methyltransferase 1/metabolism , DNA (Cytosine-5-)-Methyltransferase 1/genetics , Antimetabolites, Antineoplastic/pharmacology , Antimetabolites, Antineoplastic/therapeutic use , T-Lymphocytes/drug effects , T-Lymphocytes/metabolism , DNA (Cytosine-5-)-Methyltransferases/metabolism , DNA (Cytosine-5-)-Methyltransferases/genetics , Myelodysplastic Syndromes/drug therapy , Myelodysplastic Syndromes/metabolism
2.
FEBS Lett ; 598(9): 1094-1109, 2024 May.
Article in English | MEDLINE | ID: mdl-38627195

ABSTRACT

Allele-specific epigenetic events regulate the expression of specific genes such as tumor suppressor genes. Methods to biochemically identify epigenetic regulators remain limited. Here, we used insertional chromatin immunoprecipitation (iChIP) to address this issue. iChIP combined with quantitative mass spectrometry identified DNA methyltransferase 1 (DNMT1) and epigenetic regulators as proteins that potentially interact with a region of the p16INK4A gene that is CpG-methylated in one allele in HCT116 cells. Some of the identified proteins are involved in the CpG methylation of this region, and of these, DEAD-box helicase 24 (DDX24) contributes to CpG methylation by regulating the protein levels of DNMT1. Thus, iChIP is a useful method to identify proteins which bind to a target locus of interest.


Subject(s)
CpG Islands , Cyclin-Dependent Kinase Inhibitor p16 , DNA (Cytosine-5-)-Methyltransferase 1 , DNA Methylation , Epigenesis, Genetic , Humans , Cyclin-Dependent Kinase Inhibitor p16/genetics , Cyclin-Dependent Kinase Inhibitor p16/metabolism , DNA (Cytosine-5-)-Methyltransferase 1/metabolism , DNA (Cytosine-5-)-Methyltransferase 1/genetics , HCT116 Cells , Chromatin Immunoprecipitation , DEAD-box RNA Helicases/metabolism , DEAD-box RNA Helicases/genetics , DNA (Cytosine-5-)-Methyltransferases/metabolism , DNA (Cytosine-5-)-Methyltransferases/genetics
3.
Biochem Biophys Res Commun ; 711: 149916, 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38613866

ABSTRACT

ßIV-spectrin is a membrane-associated cytoskeletal protein that maintains the structural stability of cell membranes and integral proteins such as ion channels and transporters. Its biological functions are best characterized in the brain and heart, although recently we discovered a fundamental new role in the vascular system. Using cellular and genetic mouse models, we reported that ßIV-spectrin acts as a critical regulator of developmental and tumor-associated angiogenesis. ßIV-spectrin was shown to selectively express in proliferating endothelial cells (EC) and suppress VEGF/VEGFR2 signaling by enhancing receptor internalization and degradation. Here we examined how these events impact the downstream kinase signaling cascades and target substrates. Based on quantitative phosphoproteomics, we found that ßIV-spectrin significantly affects the phosphorylation of epigenetic regulatory enzymes in the nucleus, among which DNA methyltransferase 1 (DNMT1) was determined as a top substrate. Biochemical and immunofluorescence results showed that ßIV-spectrin inhibits DNMT1 function by activating ERK/MAPK, which in turn phosphorylates DNMT1 at S717 to impede its nuclear localization. Given that DNMT1 controls the DNA methylation patterns genome-wide, and is crucial for vascular development, our findings suggest that epigenetic regulation is a key mechanism by which ßIV-spectrin suppresses angiogenesis.


Subject(s)
DNA (Cytosine-5-)-Methyltransferase 1 , MAP Kinase Signaling System , Proteomics , DNA (Cytosine-5-)-Methyltransferase 1/metabolism , DNA (Cytosine-5-)-Methyltransferase 1/genetics , Animals , Proteomics/methods , Mice , Phosphorylation , Humans , Neovascularization, Physiologic , Spectrin/metabolism , Spectrin/genetics , Phosphoproteins/metabolism , Neovascularization, Pathologic/metabolism , Neovascularization, Pathologic/genetics , Human Umbilical Vein Endothelial Cells/metabolism , Endothelial Cells/metabolism , Angiogenesis
4.
J Neuroimmune Pharmacol ; 19(1): 16, 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38652402

ABSTRACT

Our previous research demonstrated that allergic rhinitis could impact behavior and seizure threshold in male mice. However, due to the complex hormonal cycles and hormonal influences on behavior in female mice, male mice are more commonly used for behavioral tests. In this study, we aimed to determine whether these findings were replicable in female mice and to explore the potential involvement of sexual hormones in regulating neuroinflammation in an allergic model. Our results indicate that pain threshold was decreased in female mice with allergic rhinitis and the levels of IL-23/IL-17A/IL-17R were increased in their Dorsal root ganglia. However, unlike males, female mice with AR did not display neuropsychological symptoms such as learning and memory deficits, depression, and anxiety-like behavior. This was along with decreased levels of DNA methyl transferase 1 (DNMT1) and inflammatory cytokines in their hippocampus. Ovariectomized mice were used to mitigate hormonal effects, and the results showed that they had behavioral changes and neuroinflammation in their hippocampus similar to male mice, as well as increased levels of DNMT1. These findings demonstrate sex differences in how allergic rhinitis affects behavior, pain sensitivity, and seizure thresholds. Furthermore, our data suggest that DNMT1 may be influenced by sexual hormones, which could play a role in modulating inflammation in allergic conditions.


Subject(s)
Disease Models, Animal , Neuroinflammatory Diseases , Pain Threshold , Rhinitis, Allergic , Seizures , Sex Characteristics , Animals , Female , Mice , Male , Rhinitis, Allergic/metabolism , Rhinitis, Allergic/psychology , Pain Threshold/physiology , Neuroinflammatory Diseases/metabolism , Seizures/metabolism , Behavior, Animal/physiology , Ovariectomy , DNA (Cytosine-5-)-Methyltransferase 1/metabolism
5.
Nat Commun ; 15(1): 2960, 2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38580649

ABSTRACT

DNA methylation is an essential epigenetic chromatin modification, and its maintenance in mammals requires the protein UHRF1. It is yet unclear if UHRF1 functions solely by stimulating DNA methylation maintenance by DNMT1, or if it has important additional functions. Using degron alleles, we show that UHRF1 depletion causes a much greater loss of DNA methylation than DNMT1 depletion. This is not caused by passive demethylation as UHRF1-depleted cells proliferate more slowly than DNMT1-depleted cells. Instead, bioinformatics, proteomics and genetics experiments establish that UHRF1, besides activating DNMT1, interacts with DNMT3A and DNMT3B and promotes their activity. In addition, we show that UHRF1 antagonizes active DNA demethylation by TET2. Therefore, UHRF1 has non-canonical roles that contribute importantly to DNA methylation homeostasis; these findings have practical implications for epigenetics in health and disease.


Subject(s)
DNA Methylation , Neoplasms , Humans , CCAAT-Enhancer-Binding Proteins/genetics , CCAAT-Enhancer-Binding Proteins/metabolism , Chromatin , DNA (Cytosine-5-)-Methyltransferase 1/genetics , DNA (Cytosine-5-)-Methyltransferase 1/metabolism , Neoplasms/genetics , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism
6.
Cell Mol Biol (Noisy-le-grand) ; 70(3): 197-203, 2024 Mar 31.
Article in English | MEDLINE | ID: mdl-38650132

ABSTRACT

Myocardial fibrosis is a common pathological manifestation that occurs in various cardiac diseases. The present investigation aims to reveal how DNMT1/lncRNA-ANRIL/NLRP3 influences fibrosis and cardiac fibroblast pyroptosis. Here, we used ISO to induce myocardial fibrosis in mice, and LPS and ATP to induce myocardial fibroblast pyroptosis. The results showed that DNMT1, Caspase-1, and NLRP3 expression were significantly increased in fibrotic murine myocardium and pyroptotic cardiac fibroblasts, whereas LncRNA-ANRIL expression was decreased. DNMT1 overexpression decreased the level of LncRNA-ANRIL while increasing the levels of NLRP3 and Caspase-1. Contrarily, silencing DNMT1 increased the LncRNA-ANRIL and decreased the levels of NLRP3 and Caspase-1. Silencing LncRNA-ANRIL increased the levels of NLRP3 and Caspase-1. The present findings suggest that DNMT1 can methylate LncRNA-ANRIL during the development of myocardial fibrosis and CFs cell scorching, resulting in low LncRNA-ANRIL expression, thereby influencing myocardial fibrosis and cardiac fibroblast pyroptosis.


Subject(s)
Caspase 1 , DNA (Cytosine-5-)-Methyltransferase 1 , DNA Methylation , Fibroblasts , Fibrosis , Myocardium , NLR Family, Pyrin Domain-Containing 3 Protein , Pyroptosis , RNA, Long Noncoding , Signal Transduction , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Pyroptosis/genetics , Pyroptosis/drug effects , Animals , DNA (Cytosine-5-)-Methyltransferase 1/metabolism , DNA (Cytosine-5-)-Methyltransferase 1/genetics , Caspase 1/metabolism , Caspase 1/genetics , Fibroblasts/metabolism , Myocardium/pathology , Myocardium/metabolism , Mice , DNA Methylation/genetics , Male , Mice, Inbred C57BL
7.
Cell Cycle ; 23(3): 262-278, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38597826

ABSTRACT

Esophageal cancer (EC) is a common and serious form of cancer, and while DNA methyltransferase-1 (DNMT1) promotes DNA methylation and carcinogenesis, the role of F-box protein 32 (FBXO32) in EC and its regulation by DNMT1-mediated methylation is still unclear. FBXO32 expression was examined in EC cells with high DNMT1 expression using GSE163735 dataset. RT-qPCR assessed FBXO32 expression in normal and EC cells, and impact of higher FBXO32 expression on cell proliferation, migration, and invasion was evaluated, along with EMT-related proteins. The xenograft model established by injecting EC cells transfected with FBXO32 was used to evaluate tumor growth, apoptosis, and tumor cells proliferation and metastasis. Chromatin immunoprecipitation (ChIP) assay was employed to study the interaction between DNMT1 and FBXO32. HitPredict, co-immunoprecipitation (Co-IP), and Glutathione-S-transferase (GST) pulldown assay analyzed the interaction between FBXO32 and cyclin dependent kinase 9 (CDK9). Finally, the ubiquitination assay identified CDK9 ubiquitination, and its half-life was measured using cycloheximide and confirmed through western blotting. DNMT1 negatively correlated with FBXO32 expression in esophageal cells. High FBXO32 expression was associated with better overall survival in patients. Knockdown of DNMT1 in EC cells increased FBXO32 expression and suppressed malignant phenotypes. FBXO32 repressed EC tumor growth and metastasis in mice. Enrichment of DNMT1 in FBXO32 promoter region led to increased DNA methylation and reduced transcription. Mechanistically, FBXO32 degraded CDK9 through promoting its ubiquitination.


Subject(s)
Cell Proliferation , DNA (Cytosine-5-)-Methyltransferase 1 , Epigenesis, Genetic , Esophageal Neoplasms , F-Box Proteins , Gene Expression Regulation, Neoplastic , Mice, Nude , Esophageal Neoplasms/pathology , Esophageal Neoplasms/genetics , Esophageal Neoplasms/mortality , Esophageal Neoplasms/metabolism , Humans , DNA (Cytosine-5-)-Methyltransferase 1/metabolism , DNA (Cytosine-5-)-Methyltransferase 1/genetics , Animals , Cell Proliferation/genetics , F-Box Proteins/metabolism , F-Box Proteins/genetics , Cell Line, Tumor , Epigenesis, Genetic/genetics , Mice , DNA Methylation/genetics , Ubiquitination , Cell Movement/genetics , Apoptosis/genetics , Mice, Inbred BALB C , Cell Survival/genetics , Female , Male
8.
Cell Rep ; 43(3): 113908, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38446667

ABSTRACT

The multi-domain protein UHRF1 (ubiquitin-like, containing PHD and RING finger domains, 1) recruits DNMT1 for DNA methylation maintenance during DNA replication. Here, we show that MOF (males absent on the first) acetylates UHRF1 at K670 in the pre-RING linker region, whereas HDAC1 deacetylates UHRF1 at the same site. We also identify that K667 and K668 can also be acetylated by MOF when K670 is mutated. The MOF/HDAC1-mediated acetylation in UHRF1 is cell-cycle regulated and peaks at G1/S phase, in line with the function of UHRF1 in recruiting DNMT1 to maintain DNA methylation. In addition, UHRF1 acetylation significantly enhances its E3 ligase activity. Abolishing UHRF1 acetylation at these sites attenuates UHRF1-mediated H3 ubiquitination, which in turn impairs DNMT1 recruitment and DNA methylation. Taken together, these findings identify MOF as an acetyltransferase for UHRF1 and define a mechanism underlying the regulation of DNA methylation maintenance through MOF-mediated UHRF1 acetylation.


Subject(s)
DNA Methylation , Histones , Male , Humans , DNA Methylation/genetics , Histones/metabolism , Acetylation , Ubiquitin-Protein Ligases/metabolism , CCAAT-Enhancer-Binding Proteins/metabolism , Ubiquitination , DNA (Cytosine-5-)-Methyltransferase 1/metabolism
9.
Chem Biol Interact ; 392: 110907, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38395253

ABSTRACT

The regulation of gene expression is fundamental to health and life and is essentially carried out at the promoter region of the DNA of each gene. Depending on the molecular context, this region may be accessible or non-accessible (possibility of integration of RNA polymerase or not at this region). Among enzymes that control this process, DNA methyltransferase enzymes (DNMTs), are responsible for DNA demethylation at the CpG islands, particularly at the promoter regions, to regulate transcription. The aberrant activity of these enzymes, i.e. their abnormal expression or activity, can result in the repression or overactivation of gene expression. Consequently, this can generate cellular dysregulation leading to instability and tumor development. Several reports highlighted the involvement of DNMTs in human cancers. The inhibition or activation of DNMTs is a promising therapeutic approach in many human cancers. In the present work, we provide a comprehensive and critical summary of natural bioactive molecules as primary inhibitors of DNMTs in human cancers. The active compounds hold the potential to be developed as anti-cancer epidrugs targeting DNMTs.


Subject(s)
DNA (Cytosine-5-)-Methyltransferases , Neoplasms , Humans , DNA (Cytosine-5-)-Methyltransferases/genetics , Neoplasms/metabolism , DNA (Cytosine-5-)-Methyltransferase 1/genetics , CpG Islands , DNA Methylation , Epigenesis, Genetic
10.
J Cell Biol ; 223(4)2024 04 01.
Article in English | MEDLINE | ID: mdl-38376465

ABSTRACT

DNA methylation (DNAme) is a key epigenetic mark that regulates critical biological processes maintaining overall genome stability. Given its pleiotropic function, studies of DNAme dynamics are crucial, but currently available tools to interfere with DNAme have limitations and major cytotoxic side effects. Here, we present cell models that allow inducible and reversible DNAme modulation through DNMT1 depletion. By dynamically assessing whole genome and locus-specific effects of induced passive demethylation through cell divisions, we reveal a cooperative activity between DNMT1 and DNMT3B, but not of DNMT3A, to maintain and control DNAme. We show that gradual loss of DNAme is accompanied by progressive and reversible changes in heterochromatin, compartmentalization, and peripheral localization. DNA methylation loss coincides with a gradual reduction of cell fitness due to G1 arrest, with minor levels of mitotic failure. Altogether, this system allows DNMTs and DNA methylation studies with fine temporal resolution, which may help to reveal the etiologic link between DNAme dysfunction and human disease.


Subject(s)
DNA (Cytosine-5-)-Methyltransferase 1 , DNA Methylation , DNA Methyltransferase 3A , Epigenomics , Humans , Cell Division , Heterochromatin/genetics , DNA (Cytosine-5-)-Methyltransferase 1/genetics , DNA Methyltransferase 3A/genetics , Cell Line
11.
J Biol Chem ; 300(3): 105775, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38382673

ABSTRACT

In vertebrates, DNA methyltransferase 1 (DNMT1) contributes to preserving DNA methylation patterns, ensuring the stability and heritability of epigenetic marks important for gene expression regulation and the maintenance of cellular identity. Previous structural studies have elucidated the catalytic mechanism of DNMT1 and its specific recognition of hemimethylated DNA. Here, using solution nuclear magnetic resonance spectroscopy and small-angle X-ray scattering, we demonstrate that the N-terminal region of human DNMT1, while flexible, encompasses a conserved globular domain with a novel α-helical bundle-like fold. This work expands our understanding of the structure and dynamics of DNMT1 and provides a structural framework for future functional studies in relation with this new domain.


Subject(s)
DNA (Cytosine-5-)-Methyltransferase 1 , Animals , Humans , Catalytic Domain , DNA/metabolism , DNA (Cytosine-5-)-Methyltransferase 1/chemistry , DNA (Cytosine-5-)-Methyltransferase 1/metabolism , DNA Methylation , Protein Structure, Tertiary , Protein Conformation, alpha-Helical
12.
Int J Biochem Cell Biol ; 169: 106535, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38281697

ABSTRACT

Hereditary Sensory and Autonomic Neuropathy Type 1E (HSAN1E) is a rare autosomal dominant neurological disorder due to missense mutations in DNA methyltransferase 1 (DNMT1). To investigate the nature of the dominant effect, we compared methylomes of transgenic R1wtDnmt1 and R1Dnmt1Y495C mouse embryonic stem cells (mESCs) overexpressing WT and the mutant mouse proteins respectively, with the R1 (wild-type) cells. In case of R1Dnmt1Y495C, 15 out of the 20 imprinting control regions were hypomethylated with transcript level dysregulation of multiple imprinted genes in ESCs and neurons. Non-imprinted regions, minor satellites, major satellites, LINE1 and IAP repeats were unaffected. These data mirror the specific imprinting defects associated with transient removal of DNMT1 in mESCs, deletion of the maternal-effect DNMT1o variant in preimplantation mouse embryos, and in part, reprogramming to naïve human iPSCs. This is the first DNMT1 mutation demonstrated to specifically affect Imprinting Control Regions (ICRs), and reinforces the differences in maintenance methylation of ICRs over non-imprinted regions. Consistent with nervous system abnormalities in the HSAN1E disorder and involvement of imprinted genes in normal development and neurogenesis, R1Dnmt1Y495C cells showed dysregulated pluripotency and neuron marker genes, and yielded more slender, shorter, and extensively branched neurons. We speculate that R1Dnmt1Y495C cells produce predominantly dimers containing mutant proteins, leading to a gradual and specific loss of ICR methylation during early human development.


Subject(s)
DNA (Cytosine-5-)-Methyltransferase 1 , DNA Methylation , Genomic Imprinting , Animals , Humans , Mice , DNA (Cytosine-5-)-Methyltransferase 1/genetics , DNA (Cytosine-5-)-Methyltransferase 1/metabolism , DNA (Cytosine-5-)-Methyltransferases/genetics , Mouse Embryonic Stem Cells/metabolism , Mutation
13.
Funct Integr Genomics ; 24(1): 12, 2024 Jan 17.
Article in English | MEDLINE | ID: mdl-38228798

ABSTRACT

Promoter methylation is one of the most studied epigenetic modifications and it is highly relevant to the onset and progression of thyroid carcinoma (THCA). This study investigates the promoter methylation and expression pattern of intercellular adhesion molecule 5 (ICAM5) in THCA. CpG islands with aberrant methylation pattern in THCA, and the expression profiles of the corresponding genes in THCA, were analyzed using bioinformatics. ICAM5 was suggested to have a hypermethylation status, and it was highly expressed in THCA tissues and cells. Its overexpression promoted proliferation, mobility, and tumorigenic activity of THCA cells. As for the downstream signaling, ICAM5 was found to activate the MAPK/ERK and MAPK/JNK signaling pathways. Either inhibition of ERK or JNK blocked the oncogenic effects of ICAM5. DNA methyltransferases 1 (DNMT1) and DNMT3a were found to induce promoter hypermethylation of ICAM5 in THCA cells. Knockdown of DNMT1 or DNMT3a decreased the ICAM5 expression and suppressed malignant properties of THCA cells in vitro and in vivo, which were, however, restored by further artificial ICAM5 overexpression. Collectively, this study reveals that DNMT1 and DNMT3a mediates promoter hypermethylation and transcription activation of ICAM5 in THCA, which promotes malignant progression of THCA through the MAPK signaling pathway.


Subject(s)
DNA (Cytosine-5-)-Methyltransferases , Thyroid Neoplasms , Humans , DNA (Cytosine-5-)-Methyltransferases/genetics , DNA (Cytosine-5-)-Methyltransferases/metabolism , DNA (Cytosine-5-)-Methyltransferase 1/genetics , DNA (Cytosine-5-)-Methyltransferase 1/metabolism , Transcriptional Activation , DNA Methylation , Thyroid Neoplasms/genetics , Nerve Tissue Proteins/genetics , Cell Adhesion Molecules/genetics , Cell Adhesion Molecules/metabolism
14.
Hepatol Commun ; 8(2)2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38285887

ABSTRACT

BACKGROUND: As the variable clinical outcome of patients with hepatoblastoma (HB) cannot be explained by genetics alone, the identification of drugs with the potential to effectively reverse epigenetic alterations is a promising approach to overcome poor therapy response. The gene ubiquitin like with PHD and ring finger domains 1 (UHRF1) represents an encouraging epigenetic target due to its regulatory function in both DNA methylation and histone modifications and its clinical relevance in HB. METHODS: Patient-derived xenograft in vitro and in vivo models were used to study drug response. The mechanistic basis of CM-272 treatment was elucidated using RNA sequencing and western blot experiments. RESULTS: We validated in comprehensive data sets that UHRF1 is highly expressed in HB and associated with poor outcomes. The simultaneous pharmacological targeting of UHRF1-dependent DNA methylation and histone H3 methylation by the dual inhibitor CM-272 identified a selective impact on HB patient-derived xenograft cell viability while leaving healthy fibroblasts unaffected. RNA sequencing revealed downregulation of the IGF2-activated survival pathway as the main mode of action of CM-272 treatment, subsequently leading to loss of proliferation, hindered colony formation capability, reduced spheroid growth, decreased migration potential, and ultimately, induction of apoptosis in HB cells. Importantly, drug response depended on the level of IGF2 expression, and combination assays showed a strong synergistic effect of CM-272 with cisplatin. Preclinical testing of CM-272 in a transplanted patient-derived xenograft model proved its efficacy but also uncovered side effects presumably caused by its strong antitumor effect in IGF2-driven tumors. CONCLUSIONS: The inhibition of UHRF1-associated epigenetic traces, such as IGF2-mediated survival, is an attractive approach to treat high-risk HB, especially when combined with the standard-of-care therapeutic cisplatin.


Subject(s)
Hepatoblastoma , Liver Neoplasms , Humans , CCAAT-Enhancer-Binding Proteins/genetics , CCAAT-Enhancer-Binding Proteins/metabolism , Cisplatin/pharmacology , Hepatoblastoma/drug therapy , Hepatoblastoma/genetics , Insulin-Like Growth Factor II/genetics , Insulin-Like Growth Factor II/metabolism , Liver Neoplasms/drug therapy , Liver Neoplasms/genetics , Ubiquitin-Protein Ligases/genetics , DNA (Cytosine-5-)-Methyltransferase 1/antagonists & inhibitors , Histone-Lysine N-Methyltransferase/antagonists & inhibitors
15.
Analyst ; 149(4): 1002-1021, 2024 Feb 12.
Article in English | MEDLINE | ID: mdl-38204433

ABSTRACT

The abnormal expression of human DNA methyltransferases (DNMTs) is closely related with the occurrence and development of a wide range of human cancers. DNA (cytosine-5)-methyltransferase-1 (DNMT1) is the most abundant human DNA methyltransferase and is mainly responsible for genomic DNA methylation patterns. Abnormal expression of DNMT1 has been found in many kinds of tumors, and DNMT1 has become a valuable target for the diagnosis and drug therapy of diseases. Nowadays, DNMT1 has been found to be involved in multiple cancers such as pancreatic cancer, breast cancer, bladder cancer, lung cancer, gastric cancer and other cancers. In order to achieve early diagnosis and for scientific research, various analytical methods have been developed for qualitative or quantitative detection of low-abundance DNMT1 in biological samples and human tumor cells. Herein, we provide a brief explication of the research progress of DNMT1 involved in various cancer types. In addition, this review focuses on the types, principles, and applications of DNMT1 detection methods, and discusses the challenges and potential future directions of DNMT1 detection.


Subject(s)
Breast Neoplasms , DNA (Cytosine-5-)-Methyltransferases , Humans , Female , DNA (Cytosine-5-)-Methyltransferases/genetics , DNA (Cytosine-5-)-Methyltransferases/metabolism , DNA (Cytosine-5-)-Methyltransferase 1/metabolism , DNA Methylation , Breast Neoplasms/genetics , DNA/metabolism , Biomarkers/metabolism
16.
Environ Toxicol ; 39(2): 783-793, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37782699

ABSTRACT

Glioma, a prevalent and serious form of brain cancer, is associated with dysregulation of DNA methylation, where DNA methyltransferase-1 (DNMT1) plays a significant role in glioma progression. However, the involvement of F-box protein 32 (FBXO32) in glioma and its regulation by DNMT1-mediated methylation remain poorly understood. In this study, we investigated FBXO32 expression in glioma cells with high DNMT1 expression using the online dataset and correlated it with patient survival. Then impact of elevated FBXO32 expression on cell proliferation, migration, and invasion was evaluated, along with the examination of EMT-related proteins. Furthermore, a xenograft model established by injecting glioma cells stably transfected with FBXO32 was used to evaluate tumor growth, volume, and weight. The ChIP assay was employed to study the interaction between DNMT1 and the FBXO32 promoter, revealing that DNMT1 negatively correlated with FBXO32 expression in glioma cells and promoted FBXO32 promoter methylation. Moreover, we investigated the interaction between FBXO32 and SKP1 using Co-IP and GST pulldown assays, discovering that FBXO32 acts as an E3 ubiquitin ligase and promotes SKP1 ubiquitination, leading to its degradation. Interestingly, our findings demonstrated that high FBXO32 expression was associated with improved overall survival in glioma patients. Knockdown of DNMT1 in glioma cells increased FBXO32 expression and suppressed malignant phenotypes, suggesting that FBXO32 functions as a tumor suppressor in glioma. In conclusion, this study reveals a novel regulatory mechanism involving DNMT1-mediated FBXO32 expression in glioma cells, where FBXO32 acts as an E3 ubiquitin ligase to degrade SKP1 via ubiquitination. This FBXO32-mediated regulation of SKP1 activity contributes to the progression of glioma cells. These findings provide important insights into the molecular mechanisms underlying glioma progression and may hold promise for the development of targeted therapies for glioma patients.


Subject(s)
Brain Neoplasms , Glioma , Humans , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Cell Line, Tumor , Cell Proliferation/genetics , DNA (Cytosine-5-)-Methyltransferase 1/genetics , DNA Methylation/genetics , Gene Expression Regulation, Neoplastic , Glioma/genetics , Muscle Proteins/genetics , Muscle Proteins/metabolism , S-Phase Kinase-Associated Proteins/genetics , S-Phase Kinase-Associated Proteins/metabolism , SKP Cullin F-Box Protein Ligases/genetics , SKP Cullin F-Box Protein Ligases/metabolism , Ubiquitin-Protein Ligases/genetics
17.
FASEB J ; 38(1): e23378, 2024 01.
Article in English | MEDLINE | ID: mdl-38127104

ABSTRACT

In recent years, accumulating evidence has demonstrated the role of long noncoding RNAs (lncRNAs) in colon cancer. We aim to investigate the role of MIR143HG, also known as CARMN (Cardiac mesoderm enhancer-associated noncoding RNA) in colon cancer and explore the related mechanisms. An RNAseq data analysis was performed to screen differentially expressed lncRNAs associated with colon cancer. Next, MIR143HG expression was quantified in colon cancer cells. Moreover, the contributory roles of MIR143HG in the progression of colon cancer with the involvement of DNMT1 and HOXB7 (Homeobox B7) were evaluated after restored MIR143HG or depleted HOXB7. Finally, the effects of MIR143HG were investigated in vivo by measuring tumor formation in nude mice. High-throughput transcriptome sequencing was employed to validate the specific mechanisms by which MIR143HG and HOXB7 affect tumor growth in vivo. MIR143HG was found to be poorly expressed, while HOXB7 was highly expressed in colon cancer. MIR143HG could promote HOXB7 methylation by recruiting DNMT1 to reduce HOXB7 expression. Upregulation of MIR143HG or downregulation of HOXB7 inhibited cell proliferation, invasion and migration and facilitated apoptosis in colon cancer cells so as to delay the progression of colon cancer. The same trend was identified in vivo. Our study provides evidence that restoration of MIR143HG suppressed the progression of colon cancer via downregulation of HOXB7 through DNMT1-mediated HOXB7 promoter methylation. Thus, MIR143HG may be a potential candidate for the treatment of colon cancer.


Subject(s)
Colonic Neoplasms , DNA (Cytosine-5-)-Methyltransferase 1 , Homeodomain Proteins , RNA, Long Noncoding , Animals , Mice , Colonic Neoplasms/genetics , DNA (Cytosine-5-)-Methyltransferase 1/metabolism , Homeodomain Proteins/genetics , Methylation , Methyltransferases , Mice, Nude , Promoter Regions, Genetic , RNA, Long Noncoding/genetics , Transcription Factors , Humans
18.
Endocrinology ; 165(2)2023 Dec 23.
Article in English | MEDLINE | ID: mdl-38146648

ABSTRACT

Progesterone synthesized in the placenta is essential for pregnancy maintenance. CYP11A1 is a key enzyme in progesterone synthesis, and its expression increases greatly during trophoblast syncytialization. However, the underlying mechanism remains elusive. Here, we demonstrated that passive demethylation of CYP11A1 promoter accounted for the upregulation of CYP11A1 expression during syncytialization with the participation of the transcription factor C/EBPα. We found that the methylation rate of a CpG locus in the CYP11A1 promoter was significantly reduced along with decreased DNA methyltransferase 1 (DNMT1) expression and its enrichment at the CYP11A1 promoter during syncytialization. DNMT1 overexpression not only increased the methylation of this CpG locus in the CYP11A1 promoter, but also decreased CYP11A1 expression and progesterone production. In silico analysis disclosed multiple C/EBPα binding sites in both CYP11A1 and DNMT1 promoters. C/EBPα expression and its enrichments at both the DNMT1 and CYP11A1 promoters were significantly increased during syncytialization. Knocking-down C/EBPα expression increased DNMT1 while it decreased CYP11A1 expression during syncytialization. Conclusively, C/EBPα plays a dual role in the regulation of CYP11A1 during syncytialization. C/EBPα not only drives CYP11A1 expression directly, but also indirectly through downregulation of DNMT1, which leads to decreased methylation in the CpG locus of the CYP11A1 promoter, resulting in increased progesterone production during syncytialization.


Subject(s)
CCAAT-Enhancer-Binding Protein-alpha , Cholesterol Side-Chain Cleavage Enzyme , DNA (Cytosine-5-)-Methyltransferase 1 , Placenta , Female , Humans , Pregnancy , CCAAT-Enhancer-Binding Protein-alpha/genetics , CCAAT-Enhancer-Binding Protein-alpha/metabolism , Cholesterol Side-Chain Cleavage Enzyme/genetics , Cholesterol Side-Chain Cleavage Enzyme/metabolism , DNA Methylation , Placenta/metabolism , Progesterone/metabolism , Trophoblasts/metabolism , DNA (Cytosine-5-)-Methyltransferase 1/genetics , DNA (Cytosine-5-)-Methyltransferase 1/metabolism
19.
PLoS One ; 18(10): e0293466, 2023.
Article in English | MEDLINE | ID: mdl-37878642

ABSTRACT

Gastric cancer (GC) is a prominent global health issue, as it ranks as the fifth most prevalent type of cancer and the fourth most significant cause of cancer-related mortality worldwide. Although H. pylori is known to play a role in the development of GC, genetic factors also play a role in its onset and progression. Recent studies have shown that genetic polymorphisms are strongly associated with the development of GC and that certain single nucleotide polymorphisms (SNPs) can be used as biomarkers for early diagnosis and prevention. Epigenetic disturbances, such as DNA methylation, are involved in the development of GC, and mutations in the DNA methyltransferase (DNMT) gene have been found to increase the risk of GC. However, previous findings on the association between DNMTs SNPs and GC risk have been inconsistent. In this study, an updated meta-analysis of three well-studied and controversial DNMTs polymorphic loci, DNMT1 rs16999593, DNMT3A rs1550117 and DNMT3B rs1569686, was performed to provide more reliable results. It was found that DNMT1 rs16999593 was not associated with GC, DNMT3A rs1550117 may have a positive association with GC risk, and DNMT3B rs1569686 may be a protective factor for GC. These findings may provide valuable information for early diagnosis and prevention of GC, but further studies are needed to confirm these results.


Subject(s)
Genetic Predisposition to Disease , Stomach Neoplasms , Humans , Genotype , DNA Methyltransferase 3A , DNA (Cytosine-5-)-Methyltransferases/genetics , DNA (Cytosine-5-)-Methyltransferase 1/genetics , Polymorphism, Single Nucleotide , DNA Methylation , Stomach Neoplasms/genetics , Protective Factors
20.
Biomed Pharmacother ; 168: 115753, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37871559

ABSTRACT

DNMT1 (DNA methyltransferase 1) is the predominant member of the DNMT family and the most abundant DNMT in various cell types. It functions as a maintenance DNMT and is involved in various diseases, including cancer and nervous system diseases. Programmed cell death (PCD) is a fundamental mechanism that regulates cell proliferation and maintains the development and homeostasis of multicellular organisms. DNMT1 plays a regulatory role in various types of PCD, including apoptosis, autophagy, necroptosis, ferroptosis, and others. DNMT1 is closely associated with the development of various diseases by regulating key genes and pathways involved in PCD, including caspase 3/7 activities in apoptosis, Beclin 1, LC3, and some autophagy-related proteins in autophagy, glutathione peroxidase 4 (GPX4) and nuclear receptor coactivator 4 (NCOA4) in ferroptosis, and receptor-interacting protein kinase 1-receptor-interacting protein kinase 3-mixed lineage kinase domain-like protein (RIPK1-RIPK3-MLKL) in necroptosis. Our study summarizes the regulatory relationship between DNMT1 and different types of PCD in various diseases and discusses the potential of DNMT1 as a common regulatory hub in multiple types of PCD, offering a perspective for therapeutic approaches in disease.


Subject(s)
Apoptosis , DNA (Cytosine-5-)-Methyltransferase 1 , Protein Kinases , Ferroptosis , Protein Kinases/metabolism , Transcription Factors , Humans , DNA (Cytosine-5-)-Methyltransferase 1/metabolism
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