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1.
Clin Epigenetics ; 16(1): 65, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741114

RESUMO

OBJECTIVE: Youth-onset type 2 diabetes (T2D) is physiologically distinct from adult-onset, but it is not clear how the two diseases differ at a molecular level. In utero exposure to maternal type 2 diabetes (T2D) is known to be a specific risk factor for youth-onset T2D. DNA methylation (DNAm) changes associated with T2D but which differ between youth- and adult-onset might delineate the impacts of T2D development at different ages and could also determine the contribution of exposure to in utero diabetes. METHODS: We performed an epigenome-wide analysis of DNAm on whole blood from 218 youth with T2D and 77 normoglycemic controls from the iCARE (improving renal Complications in Adolescents with type 2 diabetes through REsearch) cohort. Associations were tested using multiple linear regression models while adjusting for maternal diabetes, sex, age, BMI, smoking status, second-hand smoking exposure, cell-type proportions and genetic ancestry. RESULTS: We identified 3830 differentially methylated sites associated with youth T2D onset, of which 3794 were moderately (adjusted p-value < 0.05 and effect size estimate > 0.01) associated and 36 were strongly (adjusted p-value < 0.05 and effect size estimate > 0.05) associated. A total of 3725 of these sites were not previously reported in the EWAS Atlas as associated with T2D, adult obesity or youth obesity. Moreover, three CpGs associated with youth-onset T2D in the PFKFB3 gene were also associated with maternal T2D exposure (FDR < 0.05 and effect size > 0.01). This is the first study to link PFKFB3 and T2D in youth. CONCLUSION: Our findings support that T2D in youth has different impacts on DNAm than adult-onset, and suggests that changes in DNAm could provide an important link between in utero exposure to maternal diabetes and the onset of T2D.


Assuntos
Metilação de DNA , Diabetes Mellitus Tipo 2 , Efeitos Tardios da Exposição Pré-Natal , Humanos , Diabetes Mellitus Tipo 2/genética , Feminino , Metilação de DNA/genética , Gravidez , Adolescente , Masculino , Efeitos Tardios da Exposição Pré-Natal/genética , Epigênese Genética/genética , Idade de Início , Criança , Estudos de Casos e Controles , Diabetes Gestacional/genética , Adulto , Epigenoma/genética
2.
Med Oncol ; 41(6): 135, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38704802

RESUMO

Somatic evolution selects cancer cell phenotypes that maximize survival and proliferation in dynamic environments. Although cancer cells are molecularly heterogeneous, we hypothesized convergent adaptive strategies to common host selection forces can be inferred from patterns of epigenetic and genetic evolutionary selection in similar tumors. We systematically investigated gene mutations and expression changes in lung adenocarcinomas with no common driver genes (n = 313). Although 13,461 genes were mutated in at least one sample, only 376 non-synonymous mutations evidenced positive evolutionary selection with conservation of 224 genes, while 1736 and 2430 genes exhibited ≥ two-fold increased and ≥ 50% decreased expression, respectively. Mutations under positive selection are more frequent in genes with significantly altered expression suggesting they often "hardwire" pre-existing epigenetically driven adaptations. Conserved genes averaged 16-fold higher expression in normal lung tissue compared to those with selected mutations demonstrating pathways necessary for both normal cell function and optimal cancer cell fitness. The convergent LUAD phenotype exhibits loss of differentiated functions and cell-cell interactions governing tissue organization. Conservation with increased expression is found in genes associated with cell cycle, DNA repair, p53 pathway, epigenetic modifiers, and glucose metabolism. No canonical driver gene pathways exhibit strong positive selection, but extensive down-regulation of membrane ion channels suggests decreased transmembrane potential may generate persistent proliferative signals. NCD LUADs perform niche construction generating a stiff, immunosuppressive microenvironment through selection of specific collagens and proteases. NCD LUADs evolve to a convergent phenotype through a network of interconnected genetic, epigenetic, and ecological pathways.


Assuntos
Adenocarcinoma de Pulmão , Epigênese Genética , Neoplasias Pulmonares , Mutação , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Epigênese Genética/genética , Regulação Neoplásica da Expressão Gênica/genética , Evolução Molecular , Microambiente Tumoral/genética
3.
Pathol Res Pract ; 257: 155318, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38688203

RESUMO

Breast cancer (BC) has been the focus of numerous studies aimed at identifying novel biological markers for its early detection. PIWI-interacting RNAs (piRNAs), a subset of small non-coding RNAs, have emerged as potential markers due to their aberrant expression in various cancers. PiRNAs have recently gained attention due to their aberrant expression in various cancers, including BC. PiRNAs, exhibit diverse biological activities, such as epigenetic regulation of gene and protein expression and their association with cell proliferation and metastasis has been well-established. As the field of non-coding RNAs rapidly evolves, there is great anticipation that therapies targeting piRNAs will advance swiftly. This review will delve into the various biological functions of piRNAs, such as gene suppression, transposon silencing, and epigenetic regulation of genes. The review will also highlight the role of piRNAs as either progenitors or suppressors in cancers, with a particular focus on BC. Lastly, it will touch upon the potential of piRNAs as biomarkers and therapeutic targets for BC.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama , RNA Interferente Pequeno , Humanos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Neoplasias da Mama/metabolismo , Feminino , RNA Interferente Pequeno/uso terapêutico , RNA Interferente Pequeno/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Epigênese Genética/genética , Animais
4.
Cell Cycle ; 23(3): 262-278, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38597826

RESUMO

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.


Assuntos
Proliferação de Células , DNA (Citosina-5-)-Metiltransferase 1 , Epigênese Genética , Neoplasias Esofágicas , Proteínas F-Box , Regulação Neoplásica da Expressão Gênica , Camundongos Nus , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/metabolismo , Humanos , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/genética , Animais , Proliferação de Células/genética , Proteínas F-Box/metabolismo , Proteínas F-Box/genética , Linhagem Celular Tumoral , Epigênese Genética/genética , Camundongos , Metilação de DNA/genética , Ubiquitinação , Movimento Celular/genética , Apoptose/genética , Camundongos Endogâmicos BALB C , Sobrevivência Celular/genética , Feminino , Masculino
5.
Adv Sci (Weinh) ; 11(18): e2309424, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38460162

RESUMO

Secondary trastuzumab resistance represents an evolutionary adaptation of HER2-positive breast cancer during anti-HER2 treatment. Most current studies have tended to prioritize HER2 and its associated signaling pathways, often overlooking broader but seemingly less relevant cellular processes, along with their associated genetic and epigenetic mechanisms. Here, transcriptome data is not only characterized but also examined epigenomic and 3D genome architecture information in both trastuzumab-sensitive and secondary-resistant breast cancer cells. The findings reveal that the global metabolic reprogramming associated with trastuzumab resistance may stem from genome-wide alterations in both histone modifications and chromatin structure. Specifically, the transcriptional activities of key genes involved in lipid metabolism appear to be regulated by variant promoter H3K27me3 and H3K4me3 modifications, as well as promoter-enhancer interactions. These discoveries offer valuable insights into how cancer cells adapt to anti-tumor drugs and have the potential to impact future diagnostic and treatment strategies.


Assuntos
Neoplasias da Mama , Cromatina , Epigênese Genética , Metabolismo dos Lipídeos , Receptor ErbB-2 , Trastuzumab , Humanos , Neoplasias da Mama/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Trastuzumab/uso terapêutico , Trastuzumab/farmacologia , Feminino , Epigênese Genética/genética , Epigênese Genética/efeitos dos fármacos , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Cromatina/metabolismo , Cromatina/genética , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral , Antineoplásicos Imunológicos/uso terapêutico , Antineoplásicos Imunológicos/farmacologia , Reprogramação Metabólica
6.
Clin Transl Med ; 14(3): e1614, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38456209

RESUMO

Heightened lactate production in cancer cells has been linked to various cellular mechanisms such as angiogenesis, hypoxia, macrophage polarisation and T-cell dysfunction. The lactate-induced lactylation of histone lysine residues is noteworthy, as it functions as an epigenetic modification that directly augments gene transcription from chromatin. This epigenetic modification originating from lactate effectively fosters a reliance on transcription, thereby expediting tumour progression and development. Herein, this review explores the correlation between histone lactylation and cancer characteristics, revealing histone lactylation as an innovative epigenetic process that enhances the vulnerability of cells to malignancy. Moreover, it is imperative to acknowledge the paramount importance of acknowledging innovative therapeutic methodologies for proficiently managing cancer by precisely targeting lactate signalling. This comprehensive review illuminates a crucial yet inadequately investigated aspect of histone lactylation, providing valuable insights into its clinical ramifications and prospective therapeutic interventions centred on lactylation.


Assuntos
Histonas , Reprogramação Metabólica , Humanos , Histonas/genética , Carcinogênese/genética , Ácido Láctico , Epigênese Genética/genética
7.
Life Sci Alliance ; 7(6)2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38499326

RESUMO

Atypical teratoid/rhabdoid tumors (AT/RTs) are pediatric brain tumors known for their aggressiveness and aberrant but still unresolved epigenetic regulation. To better understand their malignancy, we investigated how AT/RT-specific DNA hypermethylation was associated with gene expression and altered transcription factor binding and how it is linked to upstream regulation. Medulloblastomas, choroid plexus tumors, pluripotent stem cells, and fetal brain were used as references. A part of the genomic regions, which were hypermethylated in AT/RTs similarly as in pluripotent stem cells and demethylated in the fetal brain, were targeted by neural transcriptional regulators. AT/RT-unique DNA hypermethylation was associated with polycomb repressive complex 2 and linked to suppressed genes with a role in neural development and tumorigenesis. Activity of the several NEUROG/NEUROD pioneer factors, which are unable to bind to methylated DNA, was compromised via the suppressed expression or DNA hypermethylation of their target sites, which was also experimentally validated for NEUROD1 in medulloblastomas and AT/RT samples. These results highlight and characterize the role of DNA hypermethylation in AT/RT malignancy and halted neural cell differentiation.


Assuntos
Neoplasias Cerebelares , Meduloblastoma , Tumor Rabdoide , Criança , Humanos , Meduloblastoma/genética , Metilação de DNA/genética , Tumor Rabdoide/genética , Tumor Rabdoide/metabolismo , Tumor Rabdoide/patologia , Epigênese Genética/genética , Neoplasias Cerebelares/genética , DNA/metabolismo
8.
Curr Opin Genet Dev ; 85: 102161, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38447236

RESUMO

Sustaining cell identity and function across cell division is germane to human development, healthspan, and cancer avoidance. This relies significantly on propagation of chromatin organization between cell generations, as chromatin presents a barrier to cell fate and cell state conversions. Inheritance of chromatin states across the many cell divisions required for development and tissue homeostasis represents a major challenge, especially because chromatin is disrupted to allow passage of the DNA replication fork to synthesize the two daughter strands. This process also leads to a twofold dilution of epigenetic information in histones, which needs to be accurately restored for faithful propagation of chromatin states across cell divisions. Recent research has identified distinct multilayered mechanisms acting to propagate epigenetic information to daughter strands. Here, we summarize key principles of how epigenetic information in parental histones is transferred across DNA replication and how new histones robustly acquire the same information postreplication, representing a core component of epigenetic cell memory.


Assuntos
Epigenoma , Histonas , Humanos , Histonas/genética , Histonas/metabolismo , Epigênese Genética/genética , Cromatina/genética , Ciclo Celular/genética , Divisão Celular , Replicação do DNA/genética
9.
Int J Biol Sci ; 20(5): 1833-1854, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481814

RESUMO

The Warburg Effect is one of the most well-known cancer hallmarks. This metabolic pattern centered on lactate has extremely complex effects on various aspects of tumor microenvironment, including metabolic remodeling, immune suppression, cancer cell migration, and drug resistance development. Based on accumulating evidence, metabolites are likely to participate in the regulation of biological processes in the microenvironment and to form a feedback loop. Therefore, further revealing the key mechanism of lactate-mediated oncological effects is a reasonable scientific idea. The discovery and refinement of histone lactylation in recent years has laid a firm foundation for the above idea. Histone lactylation is a post-translational modification that occurs at lysine sites on histones. Specific enzymes, known as "writers" and "erasers", catalyze the addition or removal, respectively, of lactacyl group at target lysine sites. An increasing number of investigations have reported this modification as key to multiple cellular procedures. In this review, we discuss the close connection between histone lactylation and a series of biological processes in the tumor microenvironment, including tumorigenesis, immune infiltration, and energy metabolism. Finally, this review provides insightful perspectives, identifying promising avenues for further exploration and potential clinical application in this field of research.


Assuntos
Histonas , Neoplasias , Humanos , Epigênese Genética/genética , Lisina , Neoplasias/genética , Ácido Láctico , Microambiente Tumoral/genética
10.
Biosystems ; 238: 105181, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38479653

RESUMO

The Modern Synthesis, a pillar in biological thought, united Darwin's species origin concepts with Mendel's laws of character heredity, providing a comprehensive understanding of evolution within species. Highlighting phenotypic variation and natural selection, it elucidated the environment's role as a selective force, shaping populations over time. This framework integrated additional mechanisms, including genetic drift, random mutations, and gene flow, predicting their cumulative effects on microevolution and the emergence of new species. Beyond the Modern Synthesis, the Extended Evolutionary Synthesis expands perspectives by recognizing the role of developmental plasticity, non-genetic inheritance, and epigenetics. We suggest that these aspects coexist in the plant evolutionary process; in this context, we focus on the saltational model, emphasizing how saltation events, such as dichotomous saltation, chromosomal mutations, epigenetic phenomena, and polyploidy, contribute to rapid evolutionary changes. The saltational model proposes that certain evolutionary changes, such as the rise of new species, may result suddenly from single macromutations rather than from gradual changes in DNA sequences and allele frequencies within a species over time. These events, observed in domesticated and wild higher plants, provide well-defined mechanistic bases, revealing their profound impact on plant diversity and rapid evolutionary events. Notably, next-generation sequencing exposes the likely crucial role of allopolyploidy and autopolyploidy (saltational events) in generating new plant species, each characterized by distinct chromosomal complements. In conclusion, through this review, we offer a thorough exploration of the ongoing dissertation on the saltational model, elucidating its implications for our understanding of plant evolutionary processes and paving the way for continued research in this intriguing field.


Assuntos
Evolução Biológica , Plantas , Mutação , Plantas/genética , Epigênese Genética/genética , Seleção Genética
11.
Virchows Arch ; 484(4): 687-695, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38507065

RESUMO

Research on the DNA methylation status of gastric cancer (GC) has primarily focused on identifying invasive GC to develop biomarkers for diagnostic. However, DNA methylation in noninvasive GC remains unclear. We conducted a comprehensive DNA methylation profiling study of differentiated-type intramucosal GCs (IMCs). Illumina 850K microarrays were utilized to assess the DNA methylation profiles of formalin-fixed paraffin-embedded tissues from eight patients who were Epstein-Barr virus-negative and DNA mismatch repair proficient, including IMCs and paired adjacent nontumor mucosa. Gene expression profiling microarray data from the GEO database were analyzed via bioinformatics to identify candidate methylation genes. The final validation was conducted using quantitative real-time PCR, the TCGA methylation database, and single-sample gene set enrichment analysis (GSEA). Genome-wide DNA methylation profiling revealed a global decrease in methylation in IMCs compared with nontumor tissues. Differential methylation analysis between IMCs and nontumor tissues identified 449 differentially methylated probes, with a majority of sites showing hypomethylation in IMCs compared with nontumor tissues (66.1% vs 33.9%). Integrating two RNA-seq microarray datasets, we found one hypomethylation-upregulated gene: eEF1A2, overlapped with our DNA methylation data. The mRNA expression of eEF1A2 was higher in twenty-four IMC tissues than in their paired adjacent nontumor tissues. GSEA indicated that the functions of eEF1A2 were associated with the development of IMCs. Furthermore, TCGA data indicated that eEF1A2 is hypomethylated in advanced GC. Our study illustrates the implications of DNA methylation alterations in IMCs and suggests that aberrant hypomethylation and high mRNA expression of eEF1A2 might play a role in IMCs development.


Assuntos
Biomarcadores Tumorais , Metilação de DNA , Epigênese Genética , Perfilação da Expressão Gênica , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Epigênese Genética/genética , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Biomarcadores Tumorais/genética , Regulação Neoplásica da Expressão Gênica/genética , Fator 1 de Elongação de Peptídeos/genética , Mucosa Gástrica/patologia , Mucosa Gástrica/metabolismo
12.
Adv Biol (Weinh) ; 8(5): e2300520, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38379272

RESUMO

Nowadays, prostate cancer is one of the most common forms of malignant neoplasms in men all over the world. Against the background of increasing incidence, there is a high mortality rate from prostate cancer, which is associated with an inadequate treatment strategy. Such a high prevalence of prostate cancer requires the development of methods that can ensure early detection of the disease, improve the effectiveness of treatment, and predict the therapeutic effect. Under these circumstances, it becomes crucial to focus on the development of effective diagnostic and therapeutic approaches. Due to the development of molecular genetic methods, a large number of studies have been accumulated on the role of epigenetic regulation of gene activity in cancer development, since it is epigenetic changes that can be detected at the earliest stages of cancer development. The presence of epigenetic aberrations in tumor tissue and correlations with drug resistance suggest new therapeutic approaches. Detection of epigenetic alterations such as CpG island methylation, histone modification, and microRNAs as biomarkers will improve the diagnosis of the disease, and the use of these strategies as targets for therapy will allow for greater personalization of prostate cancer treatment.


Assuntos
Metilação de DNA , Epigênese Genética , Neoplasias da Próstata , Humanos , Masculino , Neoplasias da Próstata/genética , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia , Epigênese Genética/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Ilhas de CpG/genética
13.
Am J Hum Genet ; 111(3): 456-472, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38367619

RESUMO

The impact of tobacco exposure on health varies by race and ethnicity and is closely tied to internal nicotine dose, a marker of carcinogen uptake. DNA methylation is strongly responsive to smoking status and may mediate health effects, but study of associations with internal dose is limited. We performed a blood leukocyte epigenome-wide association study (EWAS) of urinary total nicotine equivalents (TNEs; a measure of nicotine uptake) and DNA methylation measured using the MethylationEPIC v1.0 BeadChip (EPIC) in six racial and ethnic groups across three cohort studies. In the Multiethnic Cohort Study (discovery, n = 1994), TNEs were associated with differential methylation at 408 CpG sites across >250 genomic regions (p < 9 × 10-8). The top significant sites were annotated to AHRR, F2RL3, RARA, GPR15, PRSS23, and 2q37.1, all of which had decreasing methylation with increasing TNEs. We identified 45 novel CpG sites, of which 42 were unique to the EPIC array and eight annotated to genes not previously linked with smoking-related DNA methylation. The most significant signal in a novel gene was cg03748458 in MIR383;SGCZ. Fifty-one of the 408 discovery sites were validated in the Singapore Chinese Health Study (n = 340) and the Southern Community Cohort Study (n = 394) (Bonferroni corrected p < 1.23 × 10-4). Significant heterogeneity by race and ethnicity was detected for CpG sites in MYO1G and CYTH1. Furthermore, TNEs significantly mediated the association between cigarettes per day and DNA methylation at 15 sites (average 22.5%-44.3% proportion mediated). Our multiethnic study highlights the transethnic and ethnic-specific methylation associations with internal nicotine dose, a strong predictor of smoking-related morbidities.


Assuntos
MicroRNAs , Fumantes , Humanos , Nicotina , Epigênese Genética/genética , Epigenoma , Estudos de Coortes , Estudos Prospectivos , Estudo de Associação Genômica Ampla , Metilação de DNA/genética , Ilhas de CpG/genética , Receptores de Peptídeos/genética , Receptores Acoplados a Proteínas G/genética
14.
Clin Transl Med ; 14(2): e1560, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38299304

RESUMO

Paediatric and adult astrocytomas are notably different, where clinical treatments used for adults are not as effective on children with the same form of cancer and these treatments lead to adverse long-term health concerns. Integrative omics-based studies have shown the pathology and fundamental molecular characteristics differ significantly and cannot be extrapolated from the more widely studied adult disease. Recent clinical advances in our understanding of paediatric astrocytomas, with the aid of next-generation sequencing and epigenome-wide profiling, have led to the identification of key canonical mutations that vary based on the tumour location and age of onset. These driver mutations, in particular the identification of the recurrent histone H3 mutations in high-grade tumours, have confirmed the important role epigenetic dysregulations play in cancer progression. This review summarises the current updates of the classification, epidemiology, pathogenesis and clinical management of paediatric astrocytoma based on their grades and the ongoing clinical trials. It also provides novel insights on genetic and epigenetic alterations as diagnostic biomarkers, highlighting the potential of targeting these pathways as therapeutics for this devastating childhood cancer.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Adulto , Humanos , Criança , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Astrocitoma/genética , Astrocitoma/terapia , Astrocitoma/patologia , Histonas/genética , Histonas/metabolismo , Epigênese Genética/genética , Epigenômica
15.
Exp Cell Res ; 436(2): 113976, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38401687

RESUMO

Glioma is the most common brain malignancy, characterized by high morbidity, high mortality, and treatment-resistance. Inverted CCAAT box Binding Protein of 90 kDa (ICBP90) has been reported to be involved in tumor progression and the maintenance of DNA methylation. Herein, we constructed ICBP90 over-expression and knockdown glioma cell lines, and found that ICBP90 knockdown inhibited glioma cell proliferation, migration, and invasion. ICBP90 silencing potentially enhanced cellular sensitivity to cis-platinum (DDP) and exacerbated DDP-induced pyroptosis, manifested by the elevated levels of gasdermin D-N-terminal and cleaved caspase 1; whereas, ICBP90 over-expression exhibited the opposite effects. Consistently, ICBP90 knockdown inhibited tumor growth in an in vivo mouse xenograft study using U251 cells stably expressing sh-ICBP90 and oe-ICBP90. Further experiments found that ICBP90 reduced the expression of Dickkopf 3 homolog (DKK3), a negative regulator of ß-catenin, by binding its promoter and inducing DNA methylation. ICBP90 knockdown prevented the nuclear translocation of ß-catenin and suppressed the expression of c-Myc and cyclin D1. Besides, DKK3 over-expression restored the effects of ICBP90 over-expression on cell proliferation, migration, invasion, and DDP sensitivity. Our findings suggest that ICBP90 inhibits the expression of DKK3 in glioma by maintaining DKK3 promoter methylation, thereby conducing to ICBP90-mediated carcinogenesis and drug insensitivity.


Assuntos
Glioma , beta Catenina , Humanos , Animais , Camundongos , beta Catenina/metabolismo , Cisplatino/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Metilação de DNA/genética , Epigênese Genética/genética , Glioma/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo
16.
Mol Biol Rep ; 51(1): 255, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302782

RESUMO

BACKGROUND: Mounting evidence suggests that lung adenocarcinoma (LAC) and lung squamous cell carcinoma (LSC) have different biological behaviors and therapeutic regimens in clinical practice. However, limited improvements in molecular differential diagnosis of the two entities have been achieved in recent decades. We aimed to find novel markers that could define non-small cell lung cancer (NSCLC) subtypes. METHODS: We first explored publically available databases to search for DNA methylation signatures that enable a precise discrimination of LAC and LSC. Next-generation sequencing (NGS) was then used to analyze the methylation status and sites of candidate genes in LAC/LSC tissue samples, and a quantitative methylation-sensitive PCR (qMS-PCR) assay was conducted to test the performance of the selected maker in tissue samples and bronchoalveolar lavage fluid (BALF) specimens. RESULTS: We screened 19 top-ranked methylation loci that are differentially methylated between LAC and LSC. Among these hits, 6 methylation sites are enriched within the PREX1 gene promoter, thus becoming our focus. NGS analysis confirmed markedly higher PREX1 methylation levels in LAC than in LSC and revealed the right sites for detection of PREX1 methylation. Furthermore, PREX1 methylation analysis in lung cancer tissue samples defined 9 of 11 pathologically proven LACs, as well as 12 of 14 LSCs. In addition, ~ 80% LAC BALF samples showed methylated PREX1 compared to substantially lower test positivity (0-9%) of it in LSC and other lung conditions (P < 0.01). CONCLUSION: Our pilot study identified a unique epigenetic signature that could effectively distinguish LAC from LSC in various lung samples. It may enhance our in-depth understanding of the biology of lung cancer and pave the way for better accurate diagnosis and treatment stratification in the future.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/patologia , Projetos Piloto , Adenocarcinoma/patologia , Metilação de DNA/genética , Adenocarcinoma de Pulmão/genética , Carcinoma de Células Escamosas/genética , Epigênese Genética/genética , Biomarcadores Tumorais/genética
17.
Mol Biol Rep ; 51(1): 253, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302798

RESUMO

BACKGROUND: Gastric adenocarcinoma is a prevalent form of cancer that often remains undetected in its early stages due to the lack of specific symptoms. This delayed diagnosis leads to poor clinical outcomes, underscoring the need for an effective and non-invasive method for early detection. Recent advances in cancer epigenetics have led to the identification of biomarkers that have the potential to revolutionize the early detection and monitoring of this disease. One such promising biomarker is the methylation of the FGFR2 promoter. This study aims to measure the methylation levels of a specific CpG site in the FGFR2 promoter gene in DNA extracted from blood leukocytes from patients with intestinal metaplasia, gastric cancer, and healthy control. MATERIAL AND METHODS: The CpG site of the FGFR2 gene promoter was identified in its control region. Methylation alteration of the selected FGFR2 CpG site was determined through the (methylation-sensitive restriction enzyme) MSRE-qPCR. Genomic DNA was extracted from one hundred twenty-five participants. RESULTS: The normal group had mean methylation levels of 93.23 ± 4.929%, while the IM group had a level of 69.85 ± 27.15%. In GC patients, the levels varied, with 25.96 ± 18.98% in the intestinal type and 28.30 ± 16.07% in the diffuse type. The methylation levels in the IM and GC patients were significantly lower than those in the normal control group. However, no significant difference was observed between the methylation status of the intestinal type of GC and the diffuse type. The Receiver operating characteristic (ROC) curve analysis showed that FGFR2 CpG methylation levels in GC patients compared to normal controls had a high sensitivity of 100% and specificity of 100%, with a cut-off of < 74.25%; when GC patients were compared to IM patients, the sensitivity was 85%, and the specificity was 80%, with a cut-off < 44.45%. CONCLUSIONS: The potential of the FGFR2 methylation status as a non-invasive biomarker lies in its ability to be detected in blood leukocytes, which makes it a promising tool for the early detection of intestinal metaplasia and gastric cancer. This could significantly improve the detection and management of these gastric conditions.


Assuntos
Metilação de DNA , Neoplasias Gástricas , Humanos , Metilação de DNA/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Epigênese Genética/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , DNA , Metaplasia , Ilhas de CpG/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética
18.
Cell Genom ; 4(2): 100498, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38309261

RESUMO

Long interspersed element 1 (L1) retrotransposons are implicated in human disease and evolution. Their global activity is repressed by DNA methylation, but deciphering the regulation of individual copies has been challenging. Here, we combine short- and long-read sequencing to unveil L1 methylation heterogeneity across cell types, families, and individual loci and elucidate key principles involved. We find that the youngest primate L1 families are specifically hypomethylated in pluripotent stem cells and the placenta but not in most tumors. Locally, intronic L1 methylation is intimately associated with gene transcription. Conversely, the L1 methylation state can propagate to the proximal region up to 300 bp. This phenomenon is accompanied by the binding of specific transcription factors, which drive the expression of L1 and chimeric transcripts. Finally, L1 hypomethylation alone is typically insufficient to trigger L1 expression due to redundant silencing pathways. Our results illuminate the epigenetic and transcriptional interplay between retrotransposons and their host genome.


Assuntos
Metilação de DNA , Retroelementos , Animais , Humanos , Retroelementos/genética , Metilação de DNA/genética , Elementos Nucleotídeos Longos e Dispersos/genética , Fatores de Transcrição/genética , Primatas/genética , Epigênese Genética/genética
19.
Trends Genet ; 40(3): 211-212, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38171966

RESUMO

The complex relationship between chromatin accessibility, transcriptional regulation, and cancer transitions presents a daunting puzzle. Terekhanova et al. created a pan-cancer epigenetic and transcriptomic atlas at single-cell resolution, yielding important insights into the underlying chromatin architecture of cancer transitions and novel discoveries with the potential to advance precision medicine.


Assuntos
Regulação da Expressão Gênica , Neoplasias , Humanos , Neoplasias/genética , Cromatina/genética , Transcriptoma , Epigênese Genética/genética
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