RESUMO
To reveal gene regulation mechanisms, it is essential to understand the role of regulatory elements, which are possibly distant from gene promoters. Integrative analysis of epigenetic and transcriptomic data can be used to gain insights into gene-expression regulation in specific phenotypes. Here, we discuss STITCHIT, an approach to dissect epigenetic variation in a gene-specific manner across many samples for the identification of regulatory elements without relying on peak calling algorithms. The obtained genomic regions are then further refined using a regularized linear model approach, which can also be used to predict gene expression. We illustrate the use of STITCHIT using H3k27ac ChIP-seq and RNA-seq data from the International Human Epigenome Consortium (IHEC).
Assuntos
Epigênese Genética , Epigenômica , Transcriptoma , Humanos , Epigenômica/métodos , Transcriptoma/genética , Elementos Facilitadores Genéticos , Software , Biologia Computacional/métodos , Sequenciamento de Cromatina por Imunoprecipitação/métodos , Regulação da Expressão Gênica , Algoritmos , Histonas/genética , Histonas/metabolismo , Perfilação da Expressão Gênica/métodosRESUMO
Variation within the non-coding genome may influence the regulation and expression of important genes involved in immune control such as the human leukocyte antigen (HLA) system. Class I and Class II HLA molecules are essential for peptide presentation which is required for T lymphocyte activation. Single nucleotide polymorphisms within non-coding regions of HLA Class I and Class II genes may influence the expression of these genes by affecting the binding of transcription factors and chromatin modeling molecules. Furthermore, an interplay between genetic and epigenetic factors may also influence HLA expression. Epigenetic factors such as DNA methylation and non-coding RNA, regulate gene expression without changing the DNA sequence. However, genetic variation may promote or allow genes to escape regulation by epigenetic factors, resulting in altered expression. The HLA system is central to most diseases, therefore, understanding the role of genetics and epigenetics on HLA regulation will tremendously impact healthcare. The knowledge gained from these studies may lead to novel and cost-effective diagnostic approaches and therapeutic interventions. This review discusses the role of non-coding variants on HLA regulation. Furthermore, we discuss the interplay between genetic and epigenetic factors on the regulation of HLA by evaluating literature based on polymorphisms within DNA methylation and miRNA regulatory sites within class I and Class II HLA genes. We also provide insight into the importance of the HLA non-coding genome on disease, discuss ethnic-specific differences across the HLA region and provide guidelines for future HLA studies.
Assuntos
Metilação de DNA , Epigênese Genética , Antígenos HLA , Humanos , Antígenos HLA/genética , Regulação da Expressão Gênica , Polimorfismo de Nucleotídeo Único , Variação Genética , RNA não Traduzido/genética , MicroRNAs/genéticaRESUMO
Head and neck squamous cell carcinoma (HNSCC) is a highly malignant disease with high death rates that have remained substantially unaltered for decades. Therefore, new treatment approaches are urgently needed. Human papillomavirus-negative tumors harbor areas of terminally differentiated tissue that are characterized by cornification. Dissecting this intrinsic ability of HNSCC cells to irreversibly differentiate into non-malignant cells may have tumor-targeting potential. We modeled the cornification of HNSCC cells in a primary spheroid model and analyzed the mechanisms underlying differentiation by ATAC-seq and RNA-seq. Results were verified by immunofluorescence using human HNSCC tissue of distinct anatomical locations. HNSCC cell differentiation was accompanied by cell adhesion, proliferation stop, diminished tumor-initiating potential in immunodeficient mice, and activation of a wound-healing-associated signaling program. Small promoter accessibility increased despite overall chromatin closure. Differentiating cells upregulated KRT17 and cornification markers. Although KRT17 represents a basal stem cell marker in normal mucosa, we confirm KRT17 to represent an early differentiation marker in HNSCC tissue. Cornification was frequently found surrounding necrotic areas in human tumors, indicating an involvement of pro-inflammatory stimuli. Indeed, inflammatory mediators activated the differentiation program in primary HNSCC cells. In HNSCC tissue, distinct cell differentiation states were found to create a common tissue architecture in normal mucosa and HNSCCs. Our data demonstrate a loss of cell malignancy upon faithful HNSCC cell differentiation, indicating that targeted differentiation approaches may be therapeutically valuable. Moreover, we describe KRT17 to be a candidate biomarker for HNSCC cell differentiation and early tumor detection.
Assuntos
Diferenciação Celular , Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Animais , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Camundongos , Epigênese Genética , Linhagem Celular Tumoral , Mucosa/patologia , Mucosa/metabolismo , Proliferação de Células , Regulação Neoplásica da Expressão GênicaRESUMO
Osteosarcoma (OS) is the most frequent primary malignant bone tumour, whose heterogeneity represents a major challenge for common antitumour therapies. Inflammatory cytokines are known to be necessary for OS progression. Therefore, to optimise therapy, it is important to discover reliable biomarkers by identifying the mechanism generating OS and investigating the inflammatory pathways that support the undifferentiated state. In this work, we highlight the differences of epigenetic activities of IL-1ß and TNFα, and the susceptibility of TET-1 enzymatic inhibition, in tumour progression of three different OS cell lines. Investigating DNA methylation of IL-6 promoter and determining its expression, we found that TET enzymatic inhibition influences proliferation induced by inflammatory cytokines in OS cell lines. Moreover, Bobcat 339 treatment blocks IL-1ß epigenetic action on IL-6 promoter, while only partially those of TNFα as well as inhibits IL-1ß-dependent epithelial-mesenchymal transition (EMT) process, but only partially those of TNFα. In conclusion, this work highlights that IL-1ß and TNFα have different effects on DNA demethylation in OS cell lines, making DNA methylation a potential biomarker of disease. Specifically, in IL-1ß treatment, TET-1 inhibition completely blocks tumour progression, while in TNFα actions, it is only partially effective. Given that these two inflammatory pathways can be therapeutic targets for treating these tumours, knowledge of their distinct epigenetic behaviours can be useful for developing precise and specific therapeutic strategies for this disease.
Assuntos
Metilação de DNA , Epigênese Genética , Interleucina-1beta , Osteossarcoma , Proteínas Proto-Oncogênicas , Fator de Necrose Tumoral alfa , Humanos , Interleucina-1beta/genética , Interleucina-1beta/farmacologia , Epigênese Genética/efeitos dos fármacos , Epigênese Genética/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/farmacologia , Metilação de DNA/genética , Metilação de DNA/efeitos dos fármacos , Linhagem Celular Tumoral , Proteínas Proto-Oncogênicas/genética , Osteossarcoma/genética , Osteossarcoma/tratamento farmacológico , Progressão da Doença , Regiões Promotoras Genéticas/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Oxigenases de Função Mista/genética , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Interleucina-6/genética , Neoplasias Ósseas/genética , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/patologiaRESUMO
Cytomegalovirus (CMV) infection and reactivation in solid organ transplant (SOT) recipients increases the risk of viremia, graft failure and death. Clinical studies of CMV serostatus indicate that donor positive recipient negative (D+/R-) patients have greater viremia risk than D-/R-. The majority of patients are R+ having intermediate serologic risk. To characterize the long-term impact of CMV infection and assess viremia risk, we sought to measure the effects of CMV on the recipient immune epigenome. Specifically, we profiled DNA methylation in 156 individuals before lung or kidney transplant. We found that the methylome of CMV positive SOT recipients is hyper-methylated at loci associated with neural development and Polycomb group (PcG) protein binding, and hypo-methylated at regions critical for the maturation of lymphocytes. In addition, we developed a machine learning-based model to predict the recipient CMV serostatus after correcting for cell type composition and ancestry. This CMV episcore measured at baseline in R+ individual stratifies viremia risk accurately in the lung transplant cohort, and along with serostatus the CMV episcore could be a potential biomarker for identifying R+ patients at high viremia risk.
Assuntos
Infecções por Citomegalovirus , Citomegalovirus , Metilação de DNA , Epigênese Genética , Transplante de Pulmão , Viremia , Humanos , Infecções por Citomegalovirus/virologia , Infecções por Citomegalovirus/sangue , Transplante de Pulmão/efeitos adversos , Masculino , Feminino , Citomegalovirus/genética , Pessoa de Meia-Idade , Adulto , TransplantadosRESUMO
Endocrine disrupting chemicals (EDCs) such as bisphenol S (BPS) are xenobiotic compounds that can disrupt endocrine signaling due to steric similarities to endogenous hormones. EDCs have been shown to induce disruptions in normal epigenetic programming (epimutations) and differentially expressed genes (DEGs) that predispose disease states. Most interestingly, the prevalence of epimutations following exposure to many EDCs persists over multiple generations. Many studies have described direct and prolonged effects of EDC exposure in animal models, but many questions remain about molecular mechanisms by which EDC-induced epimutations are introduced or subsequently propagated, whether there are cell type-specific susceptibilities to the same EDC, and whether this correlates with differential expression of relevant hormone receptors. We exposed cultured pluripotent (iPS), somatic (Sertoli and granulosa), and primordial germ cell-like (PGCLC) cells to BPS and found that differential incidences of BPS-induced epimutations and DEGs correlated with differential expression of relevant hormone receptors inducing epimutations near relevant hormone response elements in somatic and pluripotent, but not germ cell types. Most interestingly, we found that when iPS cells were exposed to BPS and then induced to differentiate into PGCLCs, the prevalence of epimutations and DEGs was largely retained, however, >90% of the specific epimutations and DEGs were replaced by novel epimutations and DEGs. These results suggest a unique mechanism by which an EDC-induced epimutated state may be propagated transgenerationally.
Assuntos
Disruptores Endócrinos , Fenóis , Disruptores Endócrinos/toxicidade , Animais , Fenóis/toxicidade , Camundongos , Epigênese Genética/efeitos dos fármacos , Sulfonas/efeitos adversos , Sulfonas/toxicidade , Mutação , Masculino , FemininoRESUMO
Previous studies have shown cord-blood DNA methylation differences in newborns conceived using assisted reproductive technologies (ART) compared to those conceived naturally. However, whether these ART-related DNA methylation differences vary with children's sex is unknown. We hypothesize that the DNA methylation differences in cord blood between ART-conceived and naturally conceived newborns also varies by the sex of the child, with distinct patterns of differential methylation present in males and females. We investigated sex differences in cord-blood DNA methylation variation according to conception by ART using the Illumina MethylationEPIC platform, comparing 456 ART-conceived versus 507 naturally-conceived girls, and 503 ART-conceived and 473 naturally-conceived boys. We identified 37 differentially methylated CpGs according to ART-conception among girls, and 70 differentially methylated CpGs according to ART-conception among boys, when we used a 1% false discovery rate to account for multiple testing. Ten CpGs were differentially methylated according to conception by ART in both sexes. Among the genes that were associated with these CpGs, we found the BRCA1; NBR2 gene (two CpGs) was hypermethylated in girls while the APC2 (two CpGs) and NECAB3;ACTL10, (four CpGs) related to cellular signaling were hypomethylated in boys. These findings confirm the presence of sex-specific epigenetic differences, illustrating the nuanced impact of ART on the fetal epigenome. There is a need for further explorations into the implications for sex-specific developmental trajectories and health outcomes in ART-conceived children.
Assuntos
Metilação de DNA , Técnicas de Reprodução Assistida , Humanos , Feminino , Masculino , Recém-Nascido , Estudos de Coortes , Noruega , Ilhas de CpG , Sangue Fetal/metabolismo , Fertilização/genética , Caracteres Sexuais , Adulto , Fatores Sexuais , Epigênese Genética , GravidezRESUMO
Cancer remains a global health burden, shaped by both genetic mutations and epigenetic dysregulation. Epigenetic alteration plays a pivotal role in tumorigenesis, immune response modulation, and the emergence of treatment resistance. This review emphasizes the intricate interplay between epigenetically reprogrammed cancer cells and the tumor microenvironment (TME), a relationship central to the immunoediting concept, which encompasses elimination, equilibrium, and escape phases. This review highlights the significance of CD8+ T cells as potent anticancer agents and discusses the mechanisms by which tumor cells evade immune surveillance and evolve resistance to immunotherapy. Such evasion entails the regulation of inhibitory molecules, antigen presentation machinery, and cytokine milieu. Furthermore, this review explores the complex dynamics culminating in CD8+ T cell dysfunction within the TME. In summary, this work offers insights into the indispensable role of epigenetic mechanisms in bolstering cancer cell survival amidst immunological challenges within the TME.
Assuntos
Linfócitos T CD8-Positivos , Epigênese Genética , Neoplasias , Microambiente Tumoral , Humanos , Microambiente Tumoral/imunologia , Microambiente Tumoral/genética , Neoplasias/imunologia , Neoplasias/genética , Linfócitos T CD8-Positivos/imunologia , Imunoterapia/métodos , Evasão Tumoral/genética , AnimaisRESUMO
BACKGROUND: Plasma growth differentiation factor 15 (GDF15) and N-terminal proB-type natriuretic peptide (NT-proBNP) are cardiovascular biomarkers that associate with a range of diseases. Epigenetic scores (EpiScores) for GDF15 and NT-proBNP may provide new routes for risk stratification. RESULTS: In the Generation Scotland cohort (N ≥ 16,963), GDF15 levels were associated with incident dementia, ischaemic stroke and type 2 diabetes, whereas NT-proBNP levels were associated with incident ischaemic heart disease, ischaemic stroke and type 2 diabetes (all PFDR < 0.05). Bayesian epigenome-wide association studies (EWAS) identified 12 and 4 DNA methylation (DNAm) CpG sites associated (Posterior Inclusion Probability [PIP] > 95%) with levels of GDF15 and NT-proBNP, respectively. EpiScores for GDF15 and NT-proBNP were trained in a subset of the population. The GDF15 EpiScore replicated protein associations with incident dementia, type 2 diabetes and ischaemic stroke in the Generation Scotland test set (hazard ratios (HR) range 1.36-1.41, PFDR < 0.05). The EpiScore for NT-proBNP replicated the protein association with type 2 diabetes, but failed to replicate an association with ischaemic stroke. EpiScores explained comparable variance in protein levels across both the Generation Scotland test set and the external LBC1936 test cohort (R2 range of 5.7-12.2%). In LBC1936, both EpiScores were associated with indicators of poorer brain health. Neither EpiScore was associated with incident dementia in the LBC1936 population. CONCLUSIONS: EpiScores for serum levels of GDF15 and Nt-proBNP associate with body and brain health traits. These EpiScores are provided as potential tools for disease risk stratification.
Assuntos
Biomarcadores , Metilação de DNA , Diabetes Mellitus Tipo 2 , Fator 15 de Diferenciação de Crescimento , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Humanos , Fator 15 de Diferenciação de Crescimento/sangue , Fator 15 de Diferenciação de Crescimento/genética , Peptídeo Natriurético Encefálico/sangue , Peptídeo Natriurético Encefálico/genética , Fragmentos de Peptídeos/sangue , Fragmentos de Peptídeos/genética , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/genética , Metilação de DNA/genética , Biomarcadores/sangue , Escócia , Demência/sangue , Demência/genética , Epigênese Genética , AVC Isquêmico/sangue , AVC Isquêmico/genética , Teorema de Bayes , Estudos de CoortesRESUMO
Background: We examined differences in DNA methylation patterns in the NR3C1 and FKBP5 genes in relation to personality vulnerability to depression, resilience, and perinatal depressive symptoms, whilst also considering possible moderating effects of childhood traumatic events. Methods: N = 160 perinatal women were assessed at late pregnancy and 1 year postpartum for personality vulnerability to depression, resilience, depressive symptoms, and childhood traumatic events with self-reported questionnaires. NR3C1 and FKBP5 methylation markers were analyzed via sodium bisulfite sequencing. Associations of methylation markers with the above mentioned variables were tested using multivariable regressions. Results: NR3C1 methylation at CpGs 1, 4 and average methylation sites were negatively associated with resilience; NR3C1 methylation at CpG 2 was positively associated with postpartum depressive symptoms; methylation at CpG 4 was positively associated with prenatal depressive symptoms. The interaction between current distress due to interpersonal traumatic events and NR3C1 CpG sites in relation to personality vulnerability was significant on CpG sites 3 and 4, whereas the interaction between current distress due to total traumatic events and NR3C1 in relation to personality vulnerability was significant on CpG site 2. FKBP5 showed no significant associations with the outcomes. Conclusions: This study identified associations between NR3C1 methylation and resilience as well as perinatal depressive symptoms. Interestingly, an interaction between early trauma and personality vulnerability was noted. Our findings on these specific DNA methylation markers may, if replicated and integrated into risk prediction models, contribute to early diagnosis of mothers at risk, targeted health promotion, and early interventions.
Assuntos
Metilação de DNA , Depressão , Epigênese Genética , Receptores de Glucocorticoides , Resiliência Psicológica , Proteínas de Ligação a Tacrolimo , Humanos , Feminino , Proteínas de Ligação a Tacrolimo/genética , Adulto , Gravidez , Receptores de Glucocorticoides/genética , Depressão/genética , Personalidade/genética , Ilhas de CpG , Depressão Pós-Parto/genética , Inquéritos e Questionários , BiomarcadoresRESUMO
BACKGROUND: Breast tumorigenesis is a complex and multistep process accompanied by both genetic and epigenetic dysregulation. In contrast to the extensive studies on DNA epigenetic modifications 5-hydroxymethylcytosine (5hmC) and 5-methylcytosine (5mC) in malignant breast tumors, their roles in the early phases of breast tumorigenesis remain ambiguous. RESULTS: DNA 5hmC and 5mC exhibited a consistent and significant decrease from usual ductal hyperplasia to atypical ductal hyperplasia and subsequently to ductal carcinoma in situ (DCIS). However, 5hmC showed a modest increase in invasive ductal breast cancer compared to DCIS. Genomic analyses showed that the changes in 5hmC and 5mC levels occurred around the transcription start sites (TSSs), and the modification levels were strongly correlated with gene expression levels. Meanwhile, it was found that differentially hydroxymethylated regions (DhMRs) and differentially methylated regions (DMRs) were overlapped in the early phases and accompanied by the enrichment of active histone marks. In addition, TET2-related DNA demethylation was found to be involved in breast tumorigenesis, and four transcription factor binding sites (TFs: ESR1, FOXA1, GATA3, FOS) were enriched in TET2-related DhMRs/DMRs. Intriguingly, we also identified a certain number of common DhMRs between tumor samples and cell-free DNA (cfDNA). CONCLUSIONS: Our study reveals that dynamic changes in DNA 5hmC and 5mC play a vital role in propelling breast tumorigenesis. Both TFs and active histone marks are involved in TET2-related DNA demethylation. Concurrent changes in 5hmC signals in primary breast tumors and cfDNA may play a promising role in breast cancer screening.
Assuntos
5-Metilcitosina , Neoplasias da Mama , Proteínas de Ligação a DNA , Dioxigenases , Proteínas Proto-Oncogênicas , Humanos , 5-Metilcitosina/análogos & derivados , 5-Metilcitosina/metabolismo , Feminino , Neoplasias da Mama/genética , Proteínas de Ligação a DNA/genética , Dioxigenases/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Carcinogênese/genética , Metilação de DNA/genética , Epigênese Genética/genética , Regulação Neoplásica da Expressão Gênica , Desmetilação do DNARESUMO
Fibrosis is an abnormal tissue healing process characterized by the excessive accumulation of ECM components, such as COL I and COL III, in response to tissue injury or chronic inflammation. Recent advances in epitranscriptomics have underscored the importance of m6A modification in fibrosis. m6A, the most prevalent modification in eukaryotic RNA, is catalyzed by methyltransferases (e.g., METTL3), removed by demethylases (e.g., FTO), and recognized by reader proteins (e.g., YTHDF1/2). These modifications are crucial in regulating collagen metabolism and associated diseases. Understanding the role of m6A modification in fibrosis and other collagen-related conditions holds promise for developing targeted therapies. This review highlights the latest progress in this area.
Assuntos
Adenosina , Fibrose , Metiltransferases , Humanos , Adenosina/análogos & derivados , Adenosina/genética , Adenosina/metabolismo , Fibrose/genética , Metiltransferases/genética , Epigênese Genética/genética , Doenças do Colágeno/genética , Animais , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Colágeno/genética , Colágeno/metabolismo , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , RNA/genéticaRESUMO
In this issue of Developmental Cell, Shiraishi et al. investigate the epigenetic changes occurring during the formation of SHH medulloblastoma and show that an epigenomic shift renders Nuclear Factor I family of transcription factors oncogenic.
Assuntos
Epigênese Genética , Proteínas Hedgehog , Meduloblastoma , Fatores de Transcrição NFI , Meduloblastoma/genética , Meduloblastoma/patologia , Meduloblastoma/metabolismo , Humanos , Proteínas Hedgehog/metabolismo , Proteínas Hedgehog/genética , Fatores de Transcrição NFI/metabolismo , Fatores de Transcrição NFI/genética , Animais , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/patologia , Neoplasias Cerebelares/metabolismo , Neurofibromina 1/genética , Neurofibromina 1/metabolismo , CamundongosRESUMO
Gene expression is an intricate biological process that bridges gap between the genotype and the phenotype. Canonical and hereditable epigenetic mechanisms, such as histone and DNA modifications, regulate the release of genetic information encoded in DNA without altering the underlying sequence. Many other non-canonical players, such as chromatin regulators and noncoding RNAs, are also involved in regulating gene expression. Recently, RNA modifications (epitranscriptomics) have been shown to hold enormous potential in shaping cellular transcriptomes. However, their co-transcriptional nature and uncertain heritability mean that they fall outside the current definition of epigenetics, sparking an ongoing debate in the field. Here we will discuss the relationship between canonical and non-canonical epigenetic mechanisms that govern gene expression and offer our perspective on whether (or not) epitranscriptomic modifications can be classified as epigenetic mechanisms.
Assuntos
Epigênese Genética , Humanos , Epigênese Genética/genética , Transcriptoma/genética , Epigenômica/métodos , Metilação de DNA/genética , RNA não Traduzido/genética , Histonas/genética , Histonas/metabolismoRESUMO
Colorectal cancer (CRC) is a common malignant tumor with the third and second highest incidence and mortality rates among various malignant tumors. Despite significant advancements in the present therapy for CRC, the majority of CRC cases feature proficient mismatch repair/microsatellite stability and have no response to immunotherapy. Therefore, the search for new treatment options holds immense importance in the diagnosis and treatment of CRC. In recent years, clinical research on immunotherapy combined with epigenetic therapy has gradually increased, which may bring hope for these patients. This review explores the role of epigenetic regulation in exerting antitumor effects through its action on immune cell function and highlights the potential of certain epigenetic genes that can be used as markers of immunotherapy to predict therapeutic efficacy. We also discuss the application of epigenetic drug sensitization immunotherapy to develop new treatment options combining epigenetic therapy and immunotherapy.
Assuntos
Neoplasias Colorretais , Epigênese Genética , Imunoterapia , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/terapia , Neoplasias Colorretais/imunologia , Imunoterapia/métodos , Metilação de DNA/genéticaRESUMO
Tissue-resident memory CD8+ T cells serve as a first-line defense against many pathogens. In this issue of Immunity, Buquicchio et al. unveil the epigenomic landscapes of virus-specific CD8+ T cell subsets, highlighting common and organ-specific regulators driving their differentiation.
Assuntos
Linfócitos T CD8-Positivos , Epigenômica , Memória Imunológica , Memória Imunológica/imunologia , Memória Imunológica/genética , Humanos , Linfócitos T CD8-Positivos/imunologia , Animais , Epigênese Genética/imunologia , Diferenciação Celular/imunologia , Diferenciação Celular/genética , Especificidade de Órgãos/imunologia , Especificidade de Órgãos/genéticaRESUMO
Aging leads to alterations that precipitate or aggravate several diseases that occur across our lifespan. In the CNS, aging affects the capacity to maintain and repair the myelin sheaths that protect axons and facilitate neuronal signaling. Tiwari et al. report aging-associated transcriptional responses in microglia after demyelination, which could be reversed by epigenetic remodeling after BCG vaccination.
Assuntos
Envelhecimento , Vacina BCG , Bainha de Mielina , Remielinização , Vacina BCG/imunologia , Humanos , Envelhecimento/imunologia , Animais , Bainha de Mielina/imunologia , Bainha de Mielina/metabolismo , Microglia/imunologia , Doenças Desmielinizantes/imunologia , Epigênese Genética , Camundongos , VacinaçãoRESUMO
Osimertinib is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (EGFR-TKI) approved for patients with EGFR T790M resistance mutations as first- or second-line treatment of EGFR-positive patients. Resistance to Osimertinib will inevitably develop, and the underlying mechanisms are largely unknown. In this study, we discovered that acquired resistance to Osimertinib is associated with abnormal DNA damage response (DDR) in lung adenocarcinoma cells. We discovered that the polycomb protein Lethal(3) Malignant Brain Tumor-Like Protein 1 (L3MBTL1) regulates chromatin structure, thereby contributing to DDR and Osimertinib resistance. EGFR oncogene inhibition reduced L3MBTL1 ubiquitination while stabilizing its expression in Osimertinib-resistant cells. L3MBTL1 reduction and treatment with Osimertinib significantly inhibited DDR and proliferation of Osimertinib-resistant lung cancer cells in vitro and in vivo. L3MBTL1 binds throughout the genome and plays an important role in EGFR-TKI resistance. It also competes with 53BP1 for H4K20Me2 and inhibits the development of drug resistance in Osimertinib-resistant lung cancer cells in vitro and in vivo. Our findings suggest that L3MBTL1 inhibition is a novel approach to overcoming EGFR-TKI-acquired resistance.
Assuntos
Acrilamidas , Adenocarcinoma de Pulmão , Compostos de Anilina , Dano ao DNA , Resistencia a Medicamentos Antineoplásicos , Epigênese Genética , Receptores ErbB , Neoplasias Pulmonares , Humanos , Acrilamidas/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Compostos de Anilina/farmacologia , Compostos de Anilina/uso terapêutico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/metabolismo , Dano ao DNA/efeitos dos fármacos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Epigênese Genética/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Receptores ErbB/genética , Camundongos , Proteínas do Grupo Polycomb/metabolismo , Proteínas do Grupo Polycomb/genética , Camundongos Nus , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/genética , Inibidores de Proteínas Quinases/farmacologia , Proliferação de Células/efeitos dos fármacos , Ubiquitinação/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Indóis , PirimidinasRESUMO
Despite recent advances in systemic therapy for hepatocellular carcinoma (HCC), the prognosis of hepatitis B virus (HBV)-induced HCC patients remains poor. By screening a sgRNA library targeting human deubiquitinases, we find that ubiquitin-specific peptidase 26 (USP26) deficiency impairs HBV-positive HCC cell proliferation. Genetically engineered murine models with Usp26 knockout confirm that Usp26 drives HCC tumorigenesis. Mechanistically, we find that the HBV-encoded protein HBx binds to the promoter and induces the production of USP26, which is an X-linked gene exclusively expressed in the testis. HBx consequently promotes the association of USP26 with SIRT1 to synergistically stabilize SIRT1 by deubiquitination, which promotes cell proliferation and impedes cell apoptosis to accelerate HCC tumorigenesis. In patients with HBV-positive HCC, USP26 is robustly induced, and its levels correlate with SIRT1 levels and poor prognosis. Collectively, our study highlights a causative link between HBV infection, deubiquitinase induction and development of HCC, identifying a druggable target, USP26.
Assuntos
Carcinoma Hepatocelular , Proliferação de Células , Epigênese Genética , Vírus da Hepatite B , Neoplasias Hepáticas , Sirtuína 1 , Transativadores , Proteínas Virais Reguladoras e Acessórias , Carcinoma Hepatocelular/virologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Humanos , Animais , Neoplasias Hepáticas/virologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Vírus da Hepatite B/genética , Camundongos , Sirtuína 1/metabolismo , Sirtuína 1/genética , Transativadores/metabolismo , Transativadores/genética , Masculino , Proliferação de Células/genética , Proteínas Virais Reguladoras e Acessórias/metabolismo , Carcinogênese/genética , Hepatite B/virologia , Hepatite B/complicações , Hepatite B/genética , Hepatite B/metabolismo , Linhagem Celular Tumoral , Camundongos Knockout , Regulação Neoplásica da Expressão Gênica , Enzimas Desubiquitinantes/metabolismo , Enzimas Desubiquitinantes/genética , Apoptose/genética , Cisteína Endopeptidases/metabolismo , Cisteína Endopeptidases/genética , Regiões Promotoras Genéticas/genéticaRESUMO
The CRISPR-Cas9 method has revolutionized the gene editing. Epigenetic changes, including DNA methylation, RNA modification, and changes in histone proteins, have been intensively studied and found to play a key role in the pathogenesis of human diseases. CRISPR-While the utility of DNA and chromatin modifications, known as epigenetics, is well understood, the functional significance of various alterations of RNA nucleotides has recently gained attention. Recent advancements in improving CRISPR-based epigenetic modifications has resulted in the availability of a powerful source that can selectively modify DNA, allowing for the maintenance of epigenetic memory over several cell divisions. Accurate identification of DNA methylation at specific locations is crucial for the prompt detection of cancer and other diseases, as DNA methylation is strongly correlated to the onset as well as the advancement of such conditions. Genetic or epigenetic perturbations can disrupt the regulation of imprinted genes, resulting in the development of diseases. When histone code editors and DNA de-/ methyltransferases are coupled with catalytically inactive Cas9 (dCas9), and CRISPRa and CRISPRi, they demonstrate excellent efficacy in editing the epigenome of eukaryotic cells. Advancing and optimizing the extracellular delivery platform can, hence, further facilitate the manipulation of CRISPR-Cas9 gene editing technique in upcoming clinical studies. The current chapter focuses on how the CRISP/ Cas9 system provides an avenue for the epigenetic modifications and its employability for human benefit.