Stem cells play a crucial role in maintaining tissue regenerative capacity and homeostasis. However, mechanisms associated with stem cell senescence require further investigation. In this study, we conducted a proteomic analysis of human dental pulp stem cells (HDPSCs) obtained from individuals of various ages. Our findings showed that the expression of NUP62 was decreased in aged HDPSCs. We discovered that NUP62 alleviated senescence-associated phenotypes and enhanced differentiation potential both in vitro and in vivo. Conversely, the knocking down of NUP62 expression aggravated the senescence-associated phenotypes and impaired the proliferation and migration capacity of HDPSCs. Through RNA-sequence and decoding the epigenomic landscapes remodeled induced by NUP62 overexpression, we found that NUP62 helps alleviate senescence in HDPSCs by enhancing the nuclear transport of the transcription factor E2F1. This, in turn, stimulates the transcription of the epigenetic enzyme NSD2. Finally, the overexpression of NUP62 influences the H3K36me2 and H3K36me3 modifications of anti-aging genes (HMGA1, HMGA2, and SIRT6). Our results demonstrated that NUP62 regulates the fate of HDPSCs via NSD2-dependent epigenetic reprogramming.
Humans ; Dental Pulp/cytology* ; Nuclear Pore Complex Proteins/genetics* ; Cellular Senescence/genetics* ; Stem Cells/metabolism* ; Epigenesis, Genetic ; Cell Proliferation ; Cell Differentiation ; Histone-Lysine N-Methyltransferase/metabolism* ; Cells, Cultured ; Cellular Reprogramming ; Cell Movement ; Proteomics

Successful cloning through somatic cell nuclear transfer (SCNT) faces significant challenges due to epigenetic obstacles. Recent studies have highlighted the roles of H3K4me3 and H3K27me3 as potential contributors to these obstacles. However, the underlying mechanisms remain largely unclear. In this study, we generated genome-wide maps of H3K4me3 and H3K27me3 in mouse pre-implantation NT embryos. Our analysis revealed that aberrantly over-represented broad H3K4me3 domain and H3K27me3 signal lead to increased bivalent marks at gene promoters in NT embryos compared with naturally fertilized (NF) embryos at the 2-cell stage, which may link to relatively low levels of H3K36me3 in NT 2-cell embryos. Notably, the overexpression of Setd2, a H3K36me3 methyltransferase, successfully restored multiple epigenetic marks, including H3K36me3, H3K4me3, and H3K27me3. In addition, it reinstated the expression levels of ZGA-related genes by reestablishing H3K36me3 at gene body regions, which excluded H3K27me3 from bivalent promoters, ultimately improving cloning efficiency. These findings highlight the excessive bivalent state at gene promoters as a potent barrier and emphasize the removal of these barriers as a promising approach for achieving higher cloning efficiency.
Animals ; Mice ; Histone-Lysine N-Methyltransferase/biosynthesis* ; Histones/genetics* ; Nuclear Transfer Techniques ; Female ; Gene Expression Regulation, Developmental ; Promoter Regions, Genetic ; Epigenesis, Genetic ; Embryo, Mammalian/metabolism*

The p60 subunit of the chromatin assembly factor-1 complex, that is, chromatin assembly factor-1 subunit B (CHAF1B), is a histone H3/H4 chaperone crucial for the transcriptional regulation of cell differentiation and self-renewal. CHAF1B is overexpressed in several cancers and may represent a potential target for cancer therapy. However, its expression and clinical significance in lung squamous-cell carcinoma (LUSC) remain unclear. In this study, we performed weighted gene correlation network analysis to analyze the Gene Expression Omnibus GSE68793 LUSC dataset and identified CHAF1B as one of the most important driver gene candidates. Immunohistochemical analysis of 126 LUSC tumor samples and 80 adjacent normal lung tissues showed the marked upregulation of CHAF1B in tumor tissues and the negative association of its expression level with patient survival outcomes. Silencing of CHAF1B suppressed LUSC proliferation in vitro and LUSC tumor growth in vivo. Furthermore, bulk RNA sequencing of CHAF1B knockdown cells indicated SET domain containing 7 (SETD7) as a significant CHAF1B target gene. In addition, CHAF1B competitively binds to the SETD7 promoter region and represses its transcription. Altogether, these results imply that CHAF1B plays a vital role in LUSC tumorigenesis and may represent a potential molecular target for this deadly disease.
Humans ; Lung Neoplasms/metabolism* ; Histone-Lysine N-Methyltransferase/metabolism* ; Carcinoma, Squamous Cell/metabolism* ; Gene Expression Regulation, Neoplastic ; Disease Progression ; Cell Proliferation/genetics* ; Cell Line, Tumor ; Chromatin Assembly Factor-1/metabolism* ; Animals ; Mice ; Male ; Female

The occurence and development of tumors is a complicated process, which not only depends on the mutation or deletion of genes, but also is affected by epigenetic regulation. Accumulating evidences have shown that epigenetic modifications play fundamental roles in transcriptional regulation, heterochromatin formation, X chromosome inactivation, DNA damage response and tumor development. SET domain containing lysine methyltransferase 7 (SETD7) was initially identified as an important lysine methyltransferase, which methylated histone and non-histone proteins. These modifications play fundamental roles. Once this modification disorders, it can directly lead to cell abnormalities and cause many diseases. Studies have shown that SETD7 is related to the occurence and development of various tumors, but the methylation sites of SETD7 and its regulatory mechanism have not been fully elucidated. This article summarizes the research progress of the role of SETD7 on histone and non-histone methylation modification in tumors and the molecular mechanism, in order to provide new therapeutic targets for tumor pathogenesis and diagnosis.
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Humans ; Epigenesis, Genetic ; Histone-Lysine N-Methyltransferase/metabolism* ; Lysine/metabolism* ; Lung Neoplasms/genetics* ; Histones/metabolism*

OBJECTIVES: Our previous study has verified that high level of SET and MYND domain-containing protein 2 (SMYD2) plays an important role in acquiring aggressive ability for liver cancer cells in hepatocellular carcinoma. MiR-200b as a tumor suppressor gene involves in a variety of cancers. This study aims to investigate the correlation between miR-200b and SMYD2 in hepatocellular carcinoma and the underlying mechanism. METHODS: Firstly, the levels of SMYD2 and miR-200b in hepatocellular carcinoma tissues and matched adjacent non-tumor liver tissues were tested with real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting. Secondly, we evaluated the interaction between miR-200b and SMYD2 using dual-luciferase reporter assay. Thirdly, we elucidated the effect of miR-200b on SMYD2 and its downstream targets p53/CyclinE1. Finally, we silenced SMYD2 in hepatocellular carcinoma cell lines to investigate its effect on tumor proliferation and cell cycle progression, and further confirmed the correlation among SMYD2 and p53/CyclinE1. RESULTS: Compared with the matched adjacent non-tumor liver tissues, miR-200b was obviously decreased, and SMYD2 was significantly increased in hepatocellular carcinoma (both P<0.05). Spearman's rank correlation revealed that miR-200b expression was negatively correlated with SMYD2 (P<0.01). Computer algorithm and dual-luciferase reporter assay revealed that miR-200b directly targeted and suppressed SMYD2 in HEK 293T cells. The down-regulated miR-200b expression promoted hepatoma cell proliferation (P<0.05) and increased SMYD2 expression(P<0.01), while the up-regulated expression of miR-200b had an opposite effect. The knockdown of SMYD2 suppressed the proliferation of MHCC-97L cells (P<0.01), down-regulated CyclinE1, and up-regulated p53 expression (both P<0.05). CONCLUSIONS MiR-200b is involved in hepatocellular carcinoma progression via targeting SMYD2 and regulating SMYD2/p53/CyclinE1 signaling pathway and may be used as a potential target for hepatocellular carcinoma treatment.
Humans ; Carcinoma, Hepatocellular/pathology* ; Tumor Suppressor Protein p53/metabolism* ; MicroRNAs/metabolism* ; Cell Line, Tumor ; Signal Transduction ; Liver Neoplasms/pathology* ; Cell Proliferation/genetics* ; Histone-Lysine N-Methyltransferase/metabolism*

No abstract available.
Adult ; Antigens, CD4/*metabolism ; Antigens, CD56/*metabolism ; Bone Marrow/metabolism/pathology ; Dendritic Cells/cytology/*metabolism ; Diagnostic Errors ; Exons ; Female ; Flow Cytometry ; Gene Rearrangement ; Hematologic Neoplasms/diagnosis ; Histone-Lysine N-Methyltransferase/genetics ; Humans ; Immunohistochemistry ; In Situ Hybridization, Fluorescence ; Leukemia, Myeloid, Acute/*diagnosis ; Male ; Middle Aged ; Myeloid-Lymphoid Leukemia Protein/genetics ; Real-Time Polymerase Chain Reaction ; Sequence Analysis, DNA ; Transcription Factors/genetics ; Translocation, Genetic

No abstract available.
Base Sequence ; Cell Cycle Proteins/*genetics ; Chromosomes, Human, Pair 11 ; Chromosomes, Human, Pair 22 ; Female ; Gene Rearrangement ; Histone-Lysine N-Methyltransferase/*genetics ; Humans ; Immunophenotyping ; In Situ Hybridization, Fluorescence ; Karyotype ; Leukemia, Myeloid, Acute/*diagnosis/metabolism ; Male ; Myeloid-Lymphoid Leukemia Protein/*genetics ; Oncogene Proteins, Fusion/genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Septins/*genetics ; Sequence Analysis, DNA ; Translocation, Genetic ; Young Adult

During normal postnatal mammary gland development and adult remodeling related to the menstrual cycle, pregnancy, and lactation, ovarian hormones and peptide growth factors contribute to the delineation of a definite epithelial cell identity. This identity is maintained during cell replication in a heritable but DNA-independent manner. The preservation of cell identity is fundamental, especially when cells must undergo changes in response to intrinsic and extrinsic signals. The maintenance proteins, which are required for cell identity preservation, act epigenetically by regulating gene expression through DNA methylation, histone modification, and chromatin remodeling. Among the maintenance proteins, the Trithorax (TrxG) and Polycomb (PcG) group proteins are the best characterized. In this review, we summarize the structures and activities of the TrxG and PcG complexes and describe their pivotal roles in nuclear estrogen receptor activity. In addition, we provide evidence that perturbations in these epigenetic regulators are involved in disrupting epithelial cell identity, mammary gland remodeling, and breast cancer initiation.
Animals ; Breast Neoplasms ; genetics ; pathology ; physiopathology ; Cell Transformation, Neoplastic ; Chromatin ; genetics ; metabolism ; Epigenesis, Genetic ; physiology ; Epithelial Cells ; cytology ; Female ; Gene Expression Profiling ; Gene Expression Regulation, Developmental ; Histone-Lysine N-Methyltransferase ; Humans ; Mammary Glands, Animal ; cytology ; growth & development ; Mammary Glands, Human ; cytology ; growth & development ; Myeloid-Lymphoid Leukemia Protein ; genetics ; physiology ; Polycomb-Group Proteins ; genetics ; physiology ; Receptors, Estrogen ; metabolism

SUV39H1 is a histone 3 lysine 9 (H3K9)-specific methyltransferase that is important for heterochromatin formation and the regulation of gene expression. Chaetocin specifically inhibits SUV39H1, resulted in H3K9 methylation reduction as well as reactivation of silenced genes in cancer cells. Histone deacetylase (HDAC) inhibitors inhibit deacetylases and accumulate high levels of acetylation lead to cell cycle arrest and apoptosis. In this study, we demonstrated that treatment with chaetocin enhanced apoptosis in human leukemia HL60, KG1, Kasumi, K562, and THP1 cells. In addition, chaetocin induced the expression of cyclin-dependent kinase inhibitor 2B (p15), E-cadherin (CDH1) and frizzled family receptor 9 (FZD9) through depletion of SUV39H1 and reduced H3K9 methylation in their promoters. Co-treatment with chaetocin and HDAC inhibitor trichostatin A (TSA) dramatically increased apoptosis and produced greater activation of genes. Furthermore, this combined treatment significantly increased loss of SUV39H1 and reduced histone H3K9 trimethylation responses accompanied by increased acetylation. Importantly, co-treatment with chaetocin and TSA produced potent antileukemic effects in leukemia cells derived from patients. These in vitro findings suggest that combination therapy with SUV39H1 and HDAC inhibitors may be of potential value in the treatment of leukemia.
Acetylation/drug effects ; Adolescent ; Adult ; Aged ; Apoptosis/*drug effects ; Cadherins/metabolism ; Cell Line, Tumor ; Cyclin-Dependent Kinase Inhibitor p15/metabolism ; DNA Methylation/drug effects ; Enzyme Inhibitors/therapeutic use/*toxicity ; Frizzled Receptors/metabolism ; Gene Expression Regulation/drug effects ; HL-60 Cells ; Histone Deacetylase Inhibitors/therapeutic use/*toxicity ; Histone-Lysine N-Methyltransferase/*antagonists & inhibitors/metabolism ; Histones/genetics/metabolism ; Humans ; Hydroxamic Acids/therapeutic use/*toxicity ; K562 Cells ; Leukemia/drug therapy/metabolism/pathology ; Leukemia, Myeloid, Acute/genetics/metabolism/pathology ; Male ; Middle Aged ; Piperazines/therapeutic use/toxicity ; Promoter Regions, Genetic ; Young Adult

Histone lysine methyltransferase EZH2 has been reported to be frequently overexpressed in hepatocellular carcinoma (HCC) tissues and associated with hepatocarcinogenesis. However, the exact mechanism of EZH2 up-regulation in HCC has not been determined. In this study, we used murine hepatocyte AML12 cells to investigate the role of hepatitis B virus X protein (HBx) in regulating the expression of mEZH2. Western blot analysis demonstrated that the expression level of mEZH2 protein in AML12 cells was up-regulated by HBx in a dose-dependent manner. To further investigate the mechanism of mEZH2 overexpression, the 2500 bp regulatory sequence upstream from the first exon of the mEZH2 gene was amplified from AML12 genomic DNA and constructed into a luciferase reporter plasmid. The luciferase activity of the mEZH2 promoter significantly increased in AML12 cells co-transfected with HBx plasmid, and deleting the -486/-214 promoter region decreased HBx-induced mEZH2 promoter activation by nearly 50%. The -486/-214 region was then analyzed in the TRANSFAC 6.0 database and a typical E2F1-binding site was found. Mutation of this E2F1-binding site or knockdown of E2F1 expression by RNAi led to a dramatic decrease in HBx-induced activation of the mEZH2 promoter and mEZH2 overexpression in AML12 cells. These results provide evidence that HBx up-regulates mEZH2 expression by transactivating the mEZH2 promoter through E2F1 transcription factor, thereby providing new epigenetic evidence for the carcinogenic effect of HBx.
Animals ; Binding Sites ; Cell Line ; E2F1 Transcription Factor ; genetics ; Enhancer of Zeste Homolog 2 Protein ; Hepatocytes ; cytology ; metabolism ; virology ; Histone-Lysine N-Methyltransferase ; genetics ; metabolism ; Mice ; Plasmids ; Polycomb Repressive Complex 2 ; Promoter Regions, Genetic ; genetics ; RNA, Small Interfering ; genetics ; Trans-Activators ; genetics ; metabolism ; Transfection ; Up-Regulation