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1.
Nat Commun ; 13(1): 4440, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35922445

RESUMO

Establishment of the DNA methylation landscape of mammalian oocytes, mediated by the DNMT3A-DNMT3L complex, is crucial for reproduction and development. In mouse oocytes, high levels of DNA methylation occur exclusively in the transcriptionally active regions, with moderate to low levels of methylation in other regions. Histone H3K36me3 mediates the high levels of methylation in the transcribed regions; however, it is unknown which histone mark guides the methylation in the other regions. Here, we show that, in mouse oocytes, H3K36me2 is highly enriched in the X chromosome and is broadly distributed across all autosomes. Upon H3K36me2 depletion, DNA methylation in moderately methylated regions is selectively affected, and a methylation pattern unique to the X chromosome is switched to an autosome-like pattern. Furthermore, we find that simultaneous depletion of H3K36me2 and H3K36me3 results in global hypomethylation, comparable to that of DNMT3A depletion. Therefore, the two histone marks jointly provide the chromatin platform essential for guiding DNMT3A-dependent DNA methylation in mouse oocytes.


Assuntos
Metilação de DNA , Histonas , Animais , Cromatina/genética , Cromatina/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA Metiltransferase 3A , Metilases de Modificação do DNA/metabolismo , Histonas/genética , Histonas/metabolismo , Mamíferos/genética , Camundongos , Oócitos/metabolismo , Ligação Proteica
2.
Cell Mol Biol (Noisy-le-grand) ; 68(1): 226-236, 2022 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-35809309

RESUMO

The DNA methyltransferase (DNMT) family constitutes a conserved set of DNA-modifying enzymes which have essential functions in the modulation of epigenetics. The fundamental role of epigenetic changes in carcinogenesis and metastasis is increasingly being appreciated. DNMTs (DNMT1, DNMT3A and DNMT3B) have been shown to drive metastasis. Epigenetic machinery is installed at the target sites for the regulation of a wide variety of genes. Moreover, microRNAs, long non-coding RNAs and circular RNAs also shape the epigenetic landscape during metastasis. In this review, we have provided a snapshot of the quintessential role of DNMTs in metastasis. We also summarize how lncRNAs and circRNAs play roles in the epigenetic regulation of a myriad of genes.


Assuntos
Metilases de Modificação do DNA , Metástase Neoplásica , Neoplasias , DNA , Metilação de DNA/genética , Epigênese Genética , Humanos , MicroRNAs/genética , Metástase Neoplásica/genética , Neoplasias/patologia
3.
Cell Death Dis ; 13(7): 596, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35817771

RESUMO

Exosome-mediated delivery of circular RNAs (circRNAs) is implicated in cancer progression. However, the role of exosomal circRNAs in the chemotherapy resistance of tumours remains poorly understood. Here we identified a novel circRNA, circWDR62. It was found that circWDR62 expression was upregulated in TMZ-resistant glioma cells and TMZ-resistant glioma cell-derived exosomes compared with their controls by using high-throughput microarray analysis and quantitative real-time polymerase chain reaction, and high circWDR62 expression was associated with poor prognosis of glioma. Functionally, downregulation of circWDR62 expression could significantly inhibit the TMZ resistance and malignant progression of glioma. Further mechanistic studies showed that circWDR62 plays a role by sponging miR-370-3p as a competing endogenous RNA. Rescue experiments confirmed that MGMT is the downstream target of the circWDR62/miR-370-3p axis in glioma. In addition, circWDR62 could be transported between TMZ-resistant and TMZ-sensitive glioma cells via exosomes. Exosomal circWDR62 from TMZ-resistant cells conferred TMZ resistance in recipient sensitive cells while also enhancing the proliferation, migration and invasion of these cells. A series of clinical and in vivo trials corroborated that exosomal circWDR62 could promote TMZ chemoresistance and malignant progression of glioma. Our results demonstrate for the first time that exosome-mediated delivery of circWDR62 can promote TMZ resistance and malignant progression via targeting of the miR-370-3p/MGMT axis in vitro and in vivo in glioma, providing a new therapeutic strategy. Moreover, exosomal circWDR62 in human serum may serve as a promising therapeutic target and prognostic marker for glioma therapy.


Assuntos
Neoplasias Encefálicas , Glioma , MicroRNAs , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Glioma/tratamento farmacológico , Glioma/genética , Glioma/metabolismo , Humanos , MicroRNAs/metabolismo , RNA Circular/genética , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Proteínas Supressoras de Tumor/metabolismo
4.
BMC Med ; 20(1): 222, 2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35843958

RESUMO

BACKGROUND: At present, the extent and clinical relevance of epigenetic differences between upper tract urothelial carcinoma (UTUC) and urothelial carcinoma of the bladder (UCB) remain largely unknown. Here, we conducted a study to describe the global DNA methylation landscape of UTUC and UCB and to address the prognostic value of DNA methylation subtype and responses to the DNA methyltransferase inhibitor SGI-110 in urothelial carcinoma (UC). METHODS: Using whole-genome bisulfite sequencing (n = 49 samples), we analyzed epigenomic features and profiles of UTUC (n = 36) and UCB (n = 9). Next, we characterized potential links between DNA methylation, gene expression (n = 9 samples), and clinical outcomes. Then, we integrated an independent UTUC cohort (Fujii et al., n = 86) and UCB cohort (TCGA, n = 411) to validate the prognostic significance. Furthermore, we performed an integrative analysis of genome-wide DNA methylation and gene expression in two UC cell lines following transient DNA methyltransferase inhibitor SGI-110 treatment to identify potential epigenetic driver events that contribute to drug efficacy. RESULTS: We showed that UTUC and UCB have very similar DNA methylation profiles. Unsupervised DNA methylation classification identified two epi-clusters, Methy-High and Methy-Low, associated with distinct muscle-invasive statuses and patient outcomes. Methy-High samples were hypermethylated, immune-infiltrated, and enriched for exhausted T cells, with poor clinical outcome. SGI-110 inhibited the migration and invasion of Methy-High UC cell lines (UMUC-3 and T24) by upregulating multiple antitumor immune pathways. CONCLUSIONS: DNA methylation subtypes pave the way for predicting patient prognosis in UC. Our results provide mechanistic rationale for evaluating SGI-110 in treating UC patients in the clinic.


Assuntos
Azacitidina , Carcinoma de Células de Transição , Metilação de DNA , Metilases de Modificação do DNA , Neoplasias da Bexiga Urinária , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Carcinoma de Células de Transição/tratamento farmacológico , Carcinoma de Células de Transição/genética , Carcinoma de Células de Transição/metabolismo , Metilases de Modificação do DNA/antagonistas & inibidores , Metilases de Modificação do DNA/genética , Metilases de Modificação do DNA/metabolismo , Humanos , Prognóstico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo
5.
Int J Mol Sci ; 23(13)2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35806153

RESUMO

Epigenetic changes in DNA methylation contribute to the development of many diseases, including cancer. In glioblastoma multiforme, the most prevalent primary brain cancer and an incurable tumor with a median survival time of 15 months, a single epigenetic modification, the methylation of the O6-Methylguanine-DNA Methyltransferase (MGMT) gene, is a valid biomarker for predicting response to therapy with alkylating agents and also, independently, prognosis. More recently, the progress from single gene to whole-genome analysis of DNA methylation has allowed a better subclassification of glioblastomas. Here, we review the clinically relevant information that can be obtained by studying MGMT gene and whole-genome DNA methylation changes in glioblastomas, also highlighting benefits, including those of liquid biopsy, and pitfalls of the different detection methods. Finally, we discuss how changes in DNA methylation, especially in glioblastomas bearing mutations in the Isocitrate Dehydrogenase (IDH) 1 and 2 genes, can be exploited as targets for tailoring therapy.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Glioblastoma/diagnóstico , Glioblastoma/genética , Glioblastoma/terapia , Humanos , Isocitrato Desidrogenase/genética , Mutação , O(6)-Metilguanina-DNA Metiltransferase/genética , Regiões Promotoras Genéticas , Proteínas Supressoras de Tumor/genética
6.
Oncogene ; 41(31): 3876-3885, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35780181

RESUMO

Glioblastoma is the most common malignant brain cancer with dismal survival and prognosis. Temozolomide (TMZ) is a first-line chemotherapeutic agent for glioblastoma, but the emergence of drug resistance limits its anti-tumor activity. We previously discovered that the interferon inducible guanylate binding protein 3 (GBP3) is highly elevated and promotes tumorigenicity of glioblastoma. Here, we show that TMZ treatment significantly upregulates the expression of GBP3 and stimulator of interferon genes (STING), both of which increase TMZ-induced DNA damage repair and reduce cell apoptosis of glioblastoma cells. Mechanistically, relying on its N-terminal GTPase domain, GBP3 physically interacts with STING to stabilize STING protein levels, which in turn induces expression of p62 (Sequestosome 1), nuclear factor erythroid 2 like 2 (NFE2L2, NRF2), and O6-methlyguanine-DNA-methyltransferase (MGMT), leading to the resistance to TMZ treatment. Reducing GBP3 levels by RNA interference in glioblastoma cells markedly increases the sensitivity to TMZ treatment in vitro and in murine glioblastoma models. Clinically, GBP3 expression is high and positively correlated with STING, NRF2, p62, and MGMT expression in human glioblastoma tumors, and is associated with poor outcomes. These findings provide novel insight into TMZ resistance and suggest that GBP3 may represent a novel potential target for the treatment of glioblastoma.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Animais , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Dano ao DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Interferons/genética , Camundongos , Fator 2 Relacionado a NF-E2/genética , Temozolomida/farmacologia , Temozolomida/uso terapêutico
7.
Asian Pac J Cancer Prev ; 23(7): 2185-2190, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35901322

RESUMO

OBJECTIVE: Acute myeloid leukemia (AML) is caused by abnormal gene expression following mutations. Many of the mutations in AML lead to gene instability and poor response to treatment. Among these mutations, DNMT3A mutation is exceedingly important due to its major role in methylation and its effect on the expression of other genes. Aberrant methylation due to DNMT3A mutations that mostly occur in exon 23, affects the overall survival (OS) of patients with AML and myelodysplastic syndromes (MDS) showing the importance of identification of these mutations. According to the association of these mutations with short overall survival and disease progression in AML patients, we aimed to investigate DNMT3A gene exon 23 mutations using HRM. METHODS: Fifty peripheral blood samples were taken from patients with AML. Mononuclear cells were isolated by ficoll method, and DNA was extracted. Then, mutation detection was detected using the HRM method. Efficacy of the HRM method in mutation detection was compared with direct sequencing method as gold standard. RESULTS: Mutations in codon 23 of the DNMT3A gene were detected in 5 patients (10%). All of the detected mutations were missense type. A comparison between direct sequencing and HRM analysis demonstrated full concordance of mutation detection. CONCLUSION: According to the full consistency between the HRM and direct sequencing methods, HRM is suggested to be adopted as an alternative for the common time-consuming methods in detecting the gene mutations.


Assuntos
DNA (Citosina-5-)-Metiltransferases , Leucemia Mieloide Aguda , DNA (Citosina-5-)-Metiltransferases/genética , DNA Metiltransferase 3A , Metilases de Modificação do DNA/genética , Análise Mutacional de DNA/métodos , Humanos , Mutação
8.
Medicina (Kaunas) ; 58(7)2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35888599

RESUMO

Background and Objectives: MGMT methylation is a well-described biomarker in several solid tumors and MLH1 seems to occur in the initial stages of oral carcinogenesis. The aims of this study were to evaluate MHL1 and MGMT methylation levels in oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMDs), and to integrate this information with The Cancer Genome Atlas (TCGA) database. Materials and Methods: To determine the percentage of gene methylation in MLH1 and MGMT, pyrosequencing analysis was conducted. Samples were divided as follows: (1) patients diagnosed with OSCC (N = 16); (2) patients with OPDM who developed OSCC in the same location (N = 47); and (3) patients with OPDM who developed OSCC in a different location (N = 22). As a validation cohort in this study, data from The Cancer Genomic Atlas (TCGA) database, particularly regarding Head and Neck Squamous Cell Carcinoma, was used. Results: Overall MLH1 methylation levels of 8.6 ± 11.5% and 8.1 ± 9.2% for MGMT were obtained. With regard to MHL1, the OSCC presented the highest degree of methylation with 9.3 ± 7.3% (95%CI 5.1-13.6), and with regards to MGMT, the simultaneous malignancy group presented the highest degree of methylation with 10 ± 13.5% (95%CI 6-10), although no significant differences were found between the groups (p = 0.934 and p = 0.515, respectively). The estimated survival was higher for MGMT methylated cases (19.1 months, 95%CI 19.1-19.1) than for unmethylated cases (9.4 months, 95%CI 6-12.8), but not statistically significant. Conclusions: Our results did not show a correlation between MGMT and MLH1 methylation and any clinicopathological feature or survival in our institutional cohort. MLH1 methylation was present mainly in OSCC, whilst MGMT in OPMD represented a modest contribution to field cancerization, with an overall consistency with the TCGA database.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Metilação de DNA/genética , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Proteína 1 Homóloga a MutL/genética , Regiões Promotoras Genéticas , Carcinoma de Células Escamosas de Cabeça e Pescoço , Sulfitos , Proteínas Supressoras de Tumor/genética
9.
Int J Mol Sci ; 23(15)2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35897747

RESUMO

Glioblastoma is the most frequent and lethal primary central nervous system tumor in adults, accounting for around 15% of intracranial neoplasms and 40-50% of all primary malignant brain tumors, with an annual incidence of 3-6 cases per 100,000 population. Despite maximum treatment, patients only have a median survival time of 15 months. Metformin is a biguanide drug utilized as the first-line medication in treating type 2 diabetes. Recently, researchers have noticed that metformin can contribute to antineoplastic activity. The objective of this study is to investigate the mechanism of metformin as a potential adjuvant treatment drug in glioblastoma. Glioblastoma cell lines U87MG, LNZ308, and LN229 were treated with metformin, and several cellular functions and metabolic states were evaluated. First, the proliferation capability was investigated using the MTS assay and BrdU assay, while cell apoptosis was evaluated using the annexin V assay. Next, a wound-healing assay and mesenchymal biomarkers (N-cadherin, vimentin, and Twist) were used to detect the cell migration ability and epithelial-mesenchymal transition (EMT) status of tumor cells. Gene set enrichment analysis (GSEA) was applied to the transcriptome of the metformin-treated glioblastoma cell line. Then, DCFH-DA and MitoSOX Red dyes were used to quantify reactive oxygen species (ROS) in the cytosol and mitochondria. JC-1 dye and Western blotting analysis were used to evaluate mitochondrial membrane potential and biogenesis. In addition, the combinatory effect of temozolomide (TMZ) with metformin treatment was assessed by combination index analysis. Metformin could decrease cell viability, proliferation, and migration, increase cell apoptosis, and disrupt EMT in all three glioblastoma cell lines. The GSEA study highlighted increased ROS and hypoxia in the metformin-treated glioblastoma cells. Metformin increased ROS production, impaired mitochondrial membrane potential, and reduced mitochondrial biogenesis. The combined treatment of metformin and TMZ had U87 as synergistic, LNZ308 as antagonistic, and LN229 as additive. Metformin alone or combined with TMZ could suppress mitochondrial transcription factor A, Twist, and O6-methylguanine-DNA methyltransferase (MGMT) proteins in TMZ-resistant LN229 cells. In conclusion, our study showed that metformin decreased metabolic activity, proliferation, migration, mitochondrial biogenesis, and mitochondrial membrane potential and increased apoptosis and ROS in some glioblastoma cells. The sensitivity of the TMZ-resistant glioblastoma cell line to metformin might be mediated via the suppression of mitochondrial biogenesis, EMT, and MGMT expression. Our work provides new insights into the choice of adjuvant agents in TMZ-resistant GBM therapy.


Assuntos
Neoplasias Encefálicas , Diabetes Mellitus Tipo 2 , Glioblastoma , Metformina , Antineoplásicos Alquilantes/farmacologia , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA , Diabetes Mellitus Tipo 2/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Glioblastoma/metabolismo , Humanos , Metformina/farmacologia , Metformina/uso terapêutico , O(6)-Metilguanina-DNA Metiltransferase/genética , Espécies Reativas de Oxigênio/farmacologia , Temozolomida/uso terapêutico
10.
Clin Epigenetics ; 14(1): 89, 2022 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-35842682

RESUMO

BACKGROUND: Several reports have provided crucial evidence in animal models that epigenetic modifications, such as DNA methylation, may be involved in psychostimulant-induced stable changes at the cellular level in the brain. Epigenetic editors DNA methyltransferases (DNMTs) and ten-eleven translocation enzymes (TETs) coordinate expression of gene networks, which then manifest as long-term behavioural changes. However, the extent to which aberrant DNA methylation is involved in the mechanisms of substance use disorder in humans is unclear. We previously demonstrated that cocaine modifies gene transcription, via DNA methylation, throughout the brain and in peripheral blood cells in mice. RESULTS: We treated human peripheral blood mononuclear cells (PBMCs) from healthy male donors (n = 18) in vitro with psychostimulants (amphetamine, cocaine). After treatment, we assessed mRNA levels and enzymatic activities of TETs and DNMTs, conducted genome-wide DNA methylation assays and next-generation sequencing. We found that repeated exposure to psychostimulants decreased mRNA levels and enzymatic activity of TETs and 5-hydroxymethylation levels in PBMCs. These data were in line with observed hyper- and hypomethylation and mRNA expression of marker genes (IL-10, ATP2B4). Additionally, we evaluated whether the effects of cocaine on epigenetic editors (DNMTs and TETs) and cytokines interleukin-6 (IL-6) and IL-10 could be reversed by the DNMT inhibitor decitabine. Indeed, decitabine eliminated cocaine's effect on the activity of TETs and DNMTs and decreased cytokine levels, whereas cocaine increased IL-6 and decreased IL-10. CONCLUSIONS: Our data suggest that repeated psychostimulant exposure decreases TETs' enzymatic activity in PBMCs. Co-treatment with decitabine reversed TETs' levels and modulated immune response after repeated cocaine exposure. Further investigation is needed to clarify if TET could represent a putative biomarker of psychostimulant use and if DNMT inhibition could have therapeutic potential.


Assuntos
Cocaína , Metilação de DNA , Animais , Cocaína/farmacologia , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilases de Modificação do DNA/genética , Decitabina/farmacologia , Humanos , Interleucina-10/genética , Interleucina-6/genética , Leucócitos Mononucleares/metabolismo , Masculino , Camundongos , RNA Mensageiro/genética
11.
Pharmacol Res ; 181: 106290, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35680010

RESUMO

Glioblastoma multiforme (GBM) is an aggressive brain tumor, often occurring with seizures managed with antiepileptic drugs, such as levetiracetam (LEV). This study is aimed at associating progression-free survival (PFS) and overall survival (OS) of GBM patients with LEV plasma concentration, MGMT promoter methylation, and sex. In this retrospective, non-interventional, and explorative clinical study, GBM patients underwent surgery and/or radiotherapy and received LEV during adjuvant temozolomide (TMZ) treatment. A high-performance liquid chromatography with UV-detection was used for therapeutic drug monitoring of LEV plasma concentrations. Follow-up average drug concentration was related to patients' clinical characteristics and outcomes. Forty patients (42.5 % female; mean age=54.73 ± 11.70 years) were included, and GBM MGMT methylation status was assessed. All were treated with adjuvant TMZ, and LEV for seizure control. Patients harboring methylated MGMT promoter showed a longer median PFS (460 vs. 275 days, log-rank p < 0.001). The beneficial effect of MGMT promoter methylation was more evident for females (p < 0.001) and in patients with LEV concentration ≤ 20.6 µg/mL (562 days vs. 274.5 days, p = 0.032). Female patients also showed longer OS (1220 vs. 574 days, p = 0.03). Also, higher LEV concentration (>20.6 µg/mL) synergized with MGMT promoter methylation by extending the OS (1014 vs. 406 days of patients with no methylation and low LEV average concentration, p = 0.021). Beneficial effect of higher LEV plasma levels was more evident in males (p = 0.024). Plasma concentrations of LEV may support better outcomes for chemoradiotherapy when other positive prognostic factors are lacking and may promote overall survival by synergizing with MGMT promoter methylation and male sex.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Adulto , Idoso , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Quimiorradioterapia , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/uso terapêutico , Dacarbazina/uso terapêutico , Feminino , Glioblastoma/tratamento farmacológico , Humanos , Levetiracetam/uso terapêutico , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Convulsões/tratamento farmacológico , Temozolomida/uso terapêutico , Proteínas Supressoras de Tumor/genética
12.
J Enzyme Inhib Med Chem ; 37(1): 1537-1555, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35670075

RESUMO

The DNA methyltransferases (DNMTs) were found in mammals to maintain DNA methylation. Among them, DNMT1 was the first identified, and it is an attractive target for tumour chemotherapy. DC_05 and DC_517 have been reported in our previous work, which is non-nucleoside DNMT1 inhibitor with low micromolar IC50 values and significant selectivity towards other S-adenosyl-L-methionine (SAM)-dependent protein methyltransferases. In this study, through a process of similarity-based analog searching, a series of DNMT1 inhibitors were designed, synthesized, and evaluated as anticancer agents. SAR studies were conducted based on enzymatic assays. And most of the compounds showed strong inhibitory activity on human DNMT1, especially WK-23 displayed a good inhibitory effect on human DNMT1 with an IC50 value of 5.0 µM. Importantly, the pharmacokinetic (PK) profile of WK-23 was obtained with quite satisfying oral bioavailability and elimination half-life. Taken together, WK-23 is worth developing as DNMT1-selective therapy for the treatment of malignant tumour.


Assuntos
Antineoplásicos , Neoplasias , Animais , Antineoplásicos/farmacologia , Carbazóis/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA , Metilases de Modificação do DNA/metabolismo , Humanos , Mamíferos/metabolismo
13.
J Neurooncol ; 159(1): 95-101, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35704157

RESUMO

PURPOSE: The role of obesity in glioblastoma remains unclear, as previous analyses have reported contradicting results. Here, we evaluate the prognostic impact of obesity in two trial populations; CeTeG/NOA-09 (n = 129) for MGMT methylated glioblastoma patients comparing temozolomide (TMZ) to lomustine/TMZ, and GLARIUS (n = 170) for MGMT unmethylated glioblastoma patients comparing TMZ to bevacizumab/irinotecan, both in addition to surgery and radiotherapy. METHODS: The impact of obesity (BMI ≥ 30 kg/m2) on overall survival (OS) and progression-free survival (PFS) was investigated with Kaplan-Meier analysis and log-rank tests. A multivariable Cox regression analysis was performed including known prognostic factors as covariables. RESULTS: Overall, 22.6% of patients (67 of 297) were obese. Obesity was associated with shorter survival in patients with MGMT methylated glioblastoma (median OS 22.9 (95% CI 17.7-30.8) vs. 43.2 (32.5-54.4) months for obese and non-obese patients respectively, p = 0.001), but not in MGMT unmethylated glioblastoma (median OS 17.1 (15.8-18.9) vs 17.6 (14.7-20.8) months, p = 0.26). The prognostic impact of obesity in MGMT methylated glioblastoma was confirmed in a multivariable Cox regression (adjusted odds ratio: 2.57 (95% CI 1.53-4.31), p < 0.001) adjusted for age, sex, extent of resection, baseline steroids, Karnofsky performance score, and treatment arm. CONCLUSION: Obesity was associated with shorter survival in MGMT methylated, but not in MGMT unmethylated glioblastoma patients.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/terapia , Metilação de DNA , Metilases de Modificação do DNA/genética , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Glioblastoma/complicações , Glioblastoma/diagnóstico , Glioblastoma/terapia , Humanos , Obesidade/complicações , Prognóstico , Temozolomida/uso terapêutico
14.
In Vivo ; 36(4): 1694-1702, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35738587

RESUMO

BACKGROUND/AIM: The most frequent and dangerous kind of primary brain tumor is glioblastoma multiforme (GBM). The survival rates associated with GBM are very short and molecular markers for predicting survival are needed. The aim of our study was to evaluate isocitrate dehydrogenase 1 and 2 (IDH1, IDH2), telomerase reverse transcriptase (TERT), O-6- methylguanine-DNA methyltransferase (MGMT) and alpha-thalassemia/mental retardation, X-linked (ATRX) genes with next-generation sequencing (NGS) to find potential pathological mutations and their effect on survival. MATERIALS AND METHODS: Thirty patients who had undergone craniotomy and were diagnosed with high-grade glioma were evaluated for this study. Peripheral blood samples were obtained from all participants. IDH1, IDH2, TERT, MGMT and ATRX genes were evaluated with next-generation sequencing from the samples. Survival analysis evaluated the effects of all these mutations on survival. RESULTS: The median age of the patients was 58.5 (range=11- 74) years, and 56.7% (n=17) were under 60 years of age. According to sex, male patients comprised 66.7%. Targeted NGS detected 21 chromosomal aberrations. When more than three chromosomal anomalies were accepted as a reference, anomaly in three or fewer chromosomes negatively affected overall survival (hazard ratio=2.83). CONCLUSION: Targeted NGS generates therapeutically meaningful information, providing better prognostic information than conventional histology. Our study shows that NGS provides important information on survival by helping to detect chromosomal changes that can be detected in routine blood samples. It is clear that incorporating molecular diagnostics into our standard-of-care routine will help us better understand our patients' outcomes.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Telomerase , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/patologia , Criança , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Feminino , Glioma/patologia , Humanos , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Masculino , Pessoa de Meia-Idade , Mutação , Prognóstico , Telomerase/genética , Proteínas Supressoras de Tumor/genética , Proteína Nuclear Ligada ao X/genética , Adulto Jovem
15.
J Neurooncol ; 158(2): 179-224, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35648306

RESUMO

TARGET POPULATION: These recommendations apply to adult patients with progressive or recurrent glioblastoma (GBM). QUESTION: For adult patients with progressive glioblastoma does testing for Isocitrate Dehydrogenase (IDH) 1 or 2 mutations provide new additional management or prognostic information beyond that derived from the tumor at initial presentation? RECOMMENDATION: Level III: Repeat IDH mutation testing is not necessary if the tumor is histologically similar to the primary tumor and the patient's clinical course is as expected. QUESTION: For adult patients with progressive glioblastoma does repeat testing for MGMT promoter methylation provide new or additional management or prognostic information beyond that derived from the tumor at initial presentation and what methods of detection are optimal? RECOMMENDATION: Level III: Repeat MGMT promoter methylation is not recommended. QUESTION: For adult patients with progressive glioblastoma does EGFR amplification or mutation testing provide management or prognostic information beyond that provided by histologic analysis and if performed on previous tissue samples, does it need to be repeated? RECOMMENDATION: Level III: In cases that are difficult to classify as glioblastoma on histologic features EGFR amplification testing may help in classification. If a previous EGFR amplification was detected, repeat testing is not necessary. Repeat EGFR amplification or mutational testing may be recommended in patients in which target therapy is being considered. QUESTION: For adult patients with progressive glioblastoma does large panel or whole genome sequencing provide management or prognostic information beyond that derived from histologic analysis? RECOMMENDATION: Level III: Primary or repeat large panel or whole genome sequencing may be considered in patients who are eligible or interested in molecularly guided therapy or clinical trials. QUESTION: For adult patients with progressive glioblastoma should immune checkpoint biomarker testing be performed to provide management and prognostic information beyond that obtained from histologic analysis? RECOMMENDATION: Level III: The current evidence does not support making PD-L1 or mismatch repair (MMR) enzyme activity a component of standard testing. QUESTION: For adult patients with progressive glioblastoma are there meaningful biomarkers for bevacizumab responsiveness and does their assessment provide additional information for tumor management and prognosis beyond that learned by standard histologic analysis? RECOMMENDATION: Level III: No established Bevacizumab biomarkers are currently available based upon the inclusion criteria of this guideline.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Adulto , Bevacizumab , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Receptores ErbB/genética , Glioblastoma/diagnóstico , Glioblastoma/genética , Glioblastoma/terapia , Humanos , Isocitrato Desidrogenase/genética , Mutação , Recidiva Local de Neoplasia/genética , Neurocirurgiões , Guias de Prática Clínica como Assunto , Prognóstico
16.
Artigo em Russo | MEDLINE | ID: mdl-35758076

RESUMO

Glioblastoma (GB) is one of the most aggressive primary brain tumors. Analysis of molecular genetic factors affecting prognosis in patients with GB is an important direction of fundamental and clinical researches. There are literature data on the effect of TERT gene mutations, MGMT methylation and IDH1/2 status on overall survival in patients with GB. OBJECTIVE: To evaluate the incidence of TERT gene promoter mutations in adults with primary GB and to analyze the effect of TERT mutations on relapse-free and overall survival, as well as interaction of these mutations with MGMT gene methylation and IDH1/2 mutations. MATERIAL AND METHODS: The study included 56 patients (26 women and 30 men) with histologically verified GB in which genetic and molecular investigations were performed. There were patients with life duration >3 years (n=15) and people with an extremely unfavorable course of disease (14 ones with primary multiple GB, 8 patients with GB metastases including extraaxial and 8 patients with life duration <8 months). TERT gene sequencingwas performed in all the cases, IDH1/2 status was known for 41 patients, MGMT status - for 23 patients. RESULTS: Overall survival significantly differed between patients with and without TERT mutation (56 vs 17 months, p>0.05). TERT gene promoter mutation increased the effect of IDH1/2 mutations on overall and relapse-free survival (p=0.011). No TERT and IDH1/2 gene mutations worsened prognosis. There were no significant differences between TERT status and development of primary multiple GBs, as well as extra- and intracranial metastases. CONCLUSION: Thus, the combined status of IDH1/2 and TERT mutations was a factor of better prognosis and can be proposed in clinical practice.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Telomerase , Adulto , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Feminino , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Isocitrato Desidrogenase/genética , Masculino , Mutação/genética , Prognóstico , Regiões Promotoras Genéticas/genética , Telomerase/genética , Proteínas Supressoras de Tumor/genética
17.
Molecules ; 27(9)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35566242

RESUMO

Inhibitors of epigenetic writers such as DNA methyltransferases (DNMTs) are attractive compounds for epigenetic drug and probe discovery. To advance epigenetic probes and drug discovery, chemical companies are developing focused libraries for epigenetic targets. Based on a knowledge-based approach, herein we report the identification of two quinazoline-based derivatives identified in focused libraries with sub-micromolar inhibition of DNMT1 (30 and 81 nM), more potent than S-adenosylhomocysteine. Also, both compounds had a low micromolar affinity of DNMT3A and did not inhibit DNMT3B. The enzymatic inhibitory activity of DNMT1 and DNMT3A was rationalized with molecular modeling. The quinazolines reported in this work are known to have low cell toxicity and be potent inhibitors of the epigenetic target G9a. Therefore, the quinazoline-based compounds presented are attractive not only as novel potent inhibitors of DNMTs but also as dual and selective epigenetic agents targeting two families of epigenetic writers.


Assuntos
Inibidores Enzimáticos , Quinazolinas , DNA , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA , Metilases de Modificação do DNA/química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Epigênese Genética , Quinazolinas/farmacologia
18.
Molecules ; 27(9)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35566308

RESUMO

Previous published data from our group showed the encouraging in vitro activities of six phenolic temozolomide (TMZ) ester analogues (ES8-ES12 and ES14) with up to a five-fold increase in potency compared to TMZ against glioblastoma multiform cell lines and TMZ-resistant O6-methylguanine-DNA methyl transferase (MGMT)-positive primary cells. This study investigated the stabilities of the six phenolic TMZ ester analogues in the presence of porcine liver esterase (PLE) as a hydrolytic enzyme, using high-performance liquid chromatography (HPLC), monitored by a diode-array detector (DAD). Determining the rates of hydrolysis of the esters provided a useful insight into the feasibility of progressing them to the next phase of drug development. Fifty percent of TMZ esters consisting of para nitro, chloro, phenyl and tolyl groups (ES9, ES10, ES12 and ES14) were hydrolysed within the first 4.2 min of PLE exposure, while the TMZ esters consisting of para methoxy and nitrile groups (ES8 and ES11) demonstrated increased stability, with 50% hydrolysis achieved in 7.3 and 13.7 min, respectively. In conclusion, the survival of these phenolic TMZ esters on route to the target site of a brain tumor would be a challenge, mainly due to the undesirable rapid rate of hydrolysis. These findings therefore pose a question regarding the effectiveness of these esters in an in vivo setting.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Animais , Antineoplásicos Alquilantes/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Metilases de Modificação do DNA , Enzimas Reparadoras do DNA/genética , Resistencia a Medicamentos Antineoplásicos , Esterases , Ésteres/farmacologia , Glioblastoma/tratamento farmacológico , Fígado/metabolismo , Suínos , Temozolomida/farmacologia , Proteínas Supressoras de Tumor/metabolismo
19.
Sci Rep ; 12(1): 7773, 2022 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-35545654

RESUMO

Overcoming resistance to alkylating agents has important clinical significance in glioma. Cyanidin-3-O-glucoside (C3G) has a tumor-suppressive effect on tumor cells. However, whether it plays a role in temozolomide resistance in glioma is still unclear. We constructed a TMZ-resistant LN-18/TR glioma cell line, observed the effect of C3G on TMZ resistance in this cell line, and explored the role of miR-214-5p in chemoresistance. Results showed that ß-catenin and MGMT were significantly upregulated in LN-18/TR cells. C3G upregulated miR-214-5p and enhanced the cytotoxic effect of temozolomide on LN-18/TR cells. Contrarily, C3G downregulated ß-catenin and MGMT. Moreover, the miR-214-5p mimic downregulated ß-catenin and MGMT in LN-18/TR cells, whereas the miR-214-5p inhibitor had the opposite effect; the miR-214-5p inhibitor significantly blocked the C3G-induced downregulation of ß-catenin and MGMT. C3G or the miR-214-5p mimic enhanced temozolomide-induced apoptosis in LN-18/TR cells, whereas the miR-214-5p inhibitor blocked this effect. Furthermore, C3G or miR-214-5p agomir combined with TMZ significantly inhibited the growth of LN-18/TR tumors. Collectively, our research discovered the potential signaling mechanism associated with C3G-mediated suppression of TMZ resistance in LN-18/TR cells through miR-214-5p, which can facilitate the treatment of MGMT-induced resistance in glioma cells.


Assuntos
Neoplasias Encefálicas , Glioma , MicroRNAs , Antocianinas , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Apoptose/genética , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Glioma/tratamento farmacológico , Glioma/genética , Glioma/patologia , Glucosídeos/farmacologia , Glucosídeos/uso terapêutico , Humanos , MicroRNAs/metabolismo , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Proteínas Supressoras de Tumor/genética , beta Catenina/genética , beta Catenina/metabolismo
20.
Int J Mol Sci ; 23(9)2022 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-35563629

RESUMO

Glioblastoma leads to a fatal course within two years in more than two thirds of patients. An essential cornerstone of therapy is chemotherapy with temozolomide (TMZ). The effect of TMZ is counteracted by the cellular repair enzyme O6-methylguanine-DNA methyltransferase (MGMT). The MGMT promoter methylation, the main regulator of MGMT expression, can change from primary tumor to recurrence, and TMZ may play a significant role in this process. To identify the potential mechanisms involved, three primary stem-like cell lines (one astrocytoma with the mutation of the isocitrate dehydrogenase (IDH), CNS WHO grade 4 (HGA)), and two glioblastoma (IDH-wildtype, CNS WHO grade 4) were treated with TMZ. The MGMT promoter methylation, migration, proliferation, and TMZ-response of the tumor cells were examined at different time points. The strong effects of TMZ treatment on the MGMT methylated cells were observed. Furthermore, TMZ led to a loss of the MGMT promoter hypermethylation and induced migratory rather than proliferative behavior. Cells with the unmethylated MGMT promoter showed more aggressive behavior after treatment, while HGA cells reacted heterogenously. Our study provides further evidence to consider the potential adverse effects of TMZ chemotherapy and a rationale for investigating potential relationships between TMZ treatment and change in the MGMT promoter methylation during relapse.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Glioblastoma , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Astrocitoma/tratamento farmacológico , Astrocitoma/genética , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Metilação de DNA , Metilases de Modificação do DNA/genética , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Isocitrato Desidrogenase/genética , Recidiva Local de Neoplasia/genética , Temozolomida/uso terapêutico , Organização Mundial da Saúde
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