RESUMO
Based on the impressive success of Car-T-cell therapy in the treatment of hematological malignancies, a broad application for solid tumors also appears promising. However, some important hurdles need to be overcome. One of these is certainly the identification of specific target antigens on cancer cells. Hypomethylation is a characteristic epigenetic aberration in many tumor entities. Genome-wide screenings for consistent DNA hypomethylations in tumors enable the identification of aberrantly upregulated transcripts, which might result in cell surface proteins. Thus, this approach provides a new perspective for the discovery of potential new Car-T-cell target antigens for almost every tumor entity. First, we focus on this approach as a possible treatment for prostate cancer.
RESUMO
BACKGROUND: Combining the GLP-1 receptor agonist semaglutide with the long-acting amylin analogue cagrilintide has weight-loss benefits; the impact on glycated haemoglobin (HbA1c) is unknown. This trial assessed the efficacy and safety of co-administered semaglutide with cagrilintide (CagriSema) in participants with type 2 diabetes. METHODS: This 32-week, multicentre, double-blind, phase 2 trial was conducted across 17 sites in the USA. Adults with type 2 diabetes and a BMI of 27 kg/m2 or higher on metformin with or without an SGLT2 inhibitor were randomly assigned (1:1:1) to once-weekly subcutaneous CagriSema, semaglutide, or cagrilintide (all escalated to 2·4 mg). Randomisation was done centrally using an interactive web response system and was stratified according to use of SGLT2 inhibitor treatment (yes vs no). The trial participants, investigators, and trial sponsor staff were masked to treatment assignment throughout the trial. The primary endpoint was change from baseline in HbA1c; secondary endpoints were bodyweight, fasting plasma glucose, continuous glucose monitoring (CGM) parameters, and safety. Efficacy analyses were performed in all participants who had undergone randomisation, and safety analyses in all participants who had undergone randomisation and received at least one dose of the trial medication. This trial is registered on ClinicalTrials.gov (NCT04982575) and is complete. FINDINGS: Between Aug 2 and Oct 18, 2021, 92 participants were randomly assigned to CagriSema (n=31), semaglutide (n=31), or cagrilintide (n=30). 59 (64%) participants were male; the mean age of participants was 58 years (SD 9). The mean change in HbA1c from baseline to week 32 (CagriSema: -2·2 percentage points [SE 0·15]; semaglutide: -1·8 percentage points [0·16]; cagrilintide: -0·9 percentage points [0·15]) was greater with CagriSema versus cagrilintide (estimated treatment difference -1·3 percentage points [95% CI -1·7 to -0·8]; p<0·0001), but not versus semaglutide (-0·4 percentage points [-0·8 to 0·0]; p=0·075). The mean change in bodyweight from baseline to week 32 (CagriSema: -15·6% [SE 1·26]; semaglutide: -5·1% [1·26]; cagrilintide: -8·1% [1·23]) was greater with CagriSema versus both semaglutide (p<0·0001) and cagrilintide (p<0·0001). The mean change in fasting plasma glucose from baseline to week 32 (CagriSema: -3·3 mmol/L [SE 0·3]; semaglutide: -2·5 mmol/L [0·4]; cagrilintide: -1·7 mmol/L [0·3]) was greater with CagriSema versus cagrilintide (p=0·0010) but not versus semaglutide (p=0·10). Time in range (3·9-10·0 mmol/L) was 45·9%, 32·6%, and 56·9% at baseline and 88·9%, 76·2%, and 71·7% at week 32 with CagriSema, semaglutide, and cagrilintide, respectively. Adverse events were reported by 21 (68%) participants in the CagriSema group, 22 (71%) in the semaglutide group, and 24 (80%) in the cagrilintide group. Mild or moderate gastrointestinal adverse events were most common; no level 2 or 3 hypoglycaemia was reported. No fatal adverse events were reported. INTERPRETATION: In people with type 2 diabetes, treatment with CagriSema resulted in clinically relevant improvements in glycaemic control (including CGM parameters). The mean change in HbA1c with CagriSema was greater versus cagrilintide, but not versus semaglutide. Treatment with CagriSema resulted in significantly greater weight loss versus semaglutide and cagrilintide and was well tolerated. These data support further investigation of CagriSema in this population in longer and larger phase 3 studies. FUNDING: Novo Nordisk.
Assuntos
Diabetes Mellitus Tipo 2 , Inibidores do Transportador 2 de Sódio-Glicose , Adulto , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Diabetes Mellitus Tipo 2/tratamento farmacológico , Polipeptídeo Amiloide das Ilhotas Pancreáticas/uso terapêutico , Hipoglicemiantes/efeitos adversos , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Glicemia , Automonitorização da Glicemia , Resultado do Tratamento , Peptídeos Semelhantes ao Glucagon , Método Duplo-CegoRESUMO
Acute kidney injury (AKI) is a major kidney disease with a poor clinical outcome. It is a common complication, with an incidence of 10-15% of patients admitted to hospital. This rate even increases for patients who are admitted to the intensive care unit, with an incidence of >50%. AKI is characterized by a rapid increase in serum creatinine, decrease in urine output, or both. The associated symptoms include feeling sick or being sick, diarrhoea, dehydration, decreased urine output (although occasionally the urine output remains normal), fluid retention causing swelling in the legs or ankles, shortness of breath, fatigue and nausea. However, sometimes acute kidney injury causes no signs or symptoms and is detected by lab tests. Therefore, the identification of cytokines for the early detection and diagnosis of AKI is highly desirable, as their application might enable the prevention of the progression from AKI to chronic kidney disease (CKD). In this study, we analysed the secretome of the urine of an AKI patient cohort by employing a kidney-biomarker cytokine assay. Based on these results, we suggest ADIPOQ, EGF and SERPIN3A as potential cytokines that might be able to detect AKI as early as 24 h post-surgery. For the later stages, as common cytokines for the detection of AKI in both male and female patients, we suggest VEGF, SERPIN3A, TNFSF12, ANPEP, CXCL1, REN, CLU and PLAU. These cytokines in combination might present a robust strategy for identifying the development of AKI as early as 24 h or 72 h post-surgery. Furthermore, we evaluated the effect of patient and healthy urine on human podocyte cells. We conclude that cytokines abundant in the urine of AKI patients trigger processes that are needed to repair the damaged nephron and activate TP53 and SIRT1 to maintain the balance between proliferation, angiogenesis, and cell cycle arrest.
Assuntos
Injúria Renal Aguda , Podócitos , Humanos , Masculino , Feminino , Citocinas , Sirtuína 1 , Injúria Renal Aguda/etiologia , Rim , Creatinina , Biomarcadores/urina , Proteína Supressora de Tumor p53RESUMO
Recent demographic studies predict there will be a considerable increase in the number of elderly people within the next few decades. Aging has been recognized as one of the main risk factors for the world's most prevalent diseases such as neurodegenerative disorders, cancer, cardiovascular disease, and metabolic diseases. During the process of aging, a gradual loss of tissue volume and organ function is observed, which is partially caused by replicative senescence. The capacity of cellular proliferation and replicative senescence is tightly regulated by their telomere length. When telomere length is critically shortened with progressive cell division, cells become proliferatively arrested, and DNA damage response and cellular senescence are triggered, whereupon the "Hayflick limit" is attained at this stage. Podocytes are a cell type found in the kidney glomerulus where they have major roles in blood filtration. Mature podocytes are terminal differentiated cells that are unable to undergo cell division in vivo. For this reason, the establishment of primary podocyte cell cultures has been very challenging. In our present study, we present the successful immortalization of a human podocyte progenitor cell line, of which the primary cells were isolated directly from the urine of a 51-year-old male. The immortalized cell line was cultured over the course of one year (~100 passages) with high proliferation capacity, endowed with contact inhibition and P53 expression. Furthermore, by immunofluorescence-based expression and quantitative real-time PCR for the podocyte markers CD2AP, LMX1B, NPHS1, SYNPO and WT1, we confirmed the differentiation capacity of the immortalized cells. Finally, we evaluated and confirmed the responsiveness of the immortalized cells on the main mediator angiotensin II (ANGII) of the renin-angiotensin system (RAAS). In conclusion, we have shown that it is possible to bypass cellular replicative senescence (Hayflick limit) by TERT-driven immortalization of human urine-derived pre-podocyte cells from a 51-year-old African male.
Assuntos
Angiotensina II , Sistema Renina-Angiotensina , Masculino , Humanos , Idoso , Pessoa de Meia-Idade , Angiotensina II/farmacologia , Linhagem Celular , Células Cultivadas , Senescência Celular/genéticaRESUMO
The aging process is manifested by a multitude of inter-linked biological processes. These processes contribute to genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, de-regulated nutrient-sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and altered intercellular communication. The mammalian ortholog of the yeast silent information regulator (Sir2) SIRT1 is a NAD+-dependent class III histone deacetylase and has been recognized to be involved in many of the forementioned processes. Furthermore, the physiological activity of several Sirtuin family members has been connected to the regulation of life span of lower organisms (Caenorhabditis elegans and Drosophila melanogaster) as well as mammals. In the present study, we provide evidence that SIX2-positive urine derived renal progenitor cells-UdRPCs isolated directly from human urine show typical hallmarks of aging. This includes the subsequent transcriptional downregulation of SIRT1 and its downstream targets AKT and GSK3ß with increased donor age. This transcriptional downregulation is accompanied by an increase in DNA damage and transcriptional levels of several cell cycle inhibitors such as P16. We provide evidence that the renal progenitor transcription factor SIX2 binds to the coding sequence of SIRT1. Furthermore, we show that the SIRT1 promoter region is methylation sensitive and becomes methylated during aging, dividing them into SIRT1-high and -low expressing UdRPCs. Our results highlight the importance of SIRT1 in DNA damage repair recognition in UdRPCs and the control of differentiation by regulating the activation of GSK3ß through AKT.
Assuntos
Dano ao DNA , Sirtuína 1 , Células-Tronco , Humanos , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismo , Células-Tronco/metabolismo , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Envelhecimento , Regiões Promotoras Genéticas , Metilação de DNARESUMO
BACKGROUND: Although DNA methylation in the gene promoters usually represses gene expression, the TERT hypermethylated oncological region (THOR) located 5' of the hTERT gene is hypermethylated when hTERT is expressed in diverse cancer types, including urothelial cancer (UC). METHODS: Comprehensive MeDIP and DNA methylation array analyses complemented by the technically independent method of bisulfite genomic sequencing were applied on pathologically reviewed and classified urothelial carcinoma specimens and healthy urothelial tissue samples to reveal the methylation status of THOR in detail. RESULTS: The detailed DNA methylation profiles reveal the exact positions of differentially methylated CpG dinucleotides within THOR in urothelial cancer and provide evidence ofa diverging role of methylation of these CpGs in the regulation of hTERT. In particular, our data suggest a regulating mechanism in which THOR methylation acts on hTERT expression through epigenetic silencing of the lncRNA hTERT antisense promoter-associated (hTAPAS), which represses hTERT. CONCLUSIONS: These findings precisely define the most differentially methylated CpGs of THOR in early urothelial cancer, enabling optimal design of Methylation-Specific PCR (MSPCR) primers to reliably probe these methylation differences for diagnostic and prognostic purposes. In addition, this strategy presents a prime example that is also applicable to many other malignancies. Finally, the first evidence for the underlying epigenetic mechanism regulating hTERT expression through the methylation status of THOR is provided.
RESUMO
Methyl group metabolism belongs to a relatively understudied field of research. Its importance lies in the fact that methyl group metabolic pathways are crucial for the successful conversion of dietary nutrients into the basic building blocks to carry out any cellular methylation reaction. Methyl groups play essential roles in numerous cellular functions such as DNA methylation, nucleotide- and protein biosynthesis. Especially, DNA methylation is responsible for organizing the genome into transcriptionally silent and active regions. Ultimately, it is this proper annotation that determines the quality of expression patterns required to ensure and shape the phenotypic integrity and function of a highly specialized cell type. Life is characterized by constantly changing environmental conditions, which are addressed by changes in DNA methylation. This relationship is increasingly coming into focus as it is of fundamental importance for differentiation, aging, and cancer. The stability and permanence of these metabolic processes, fueling the supplementation of methyl groups, seem to be important criteria to prevent deficiencies and erosion of the methylome. Alterations in the metabolic processes can lead to epigenetic and genetic perturbations, causative for diverse disorders, accelerated aging, and various age-related diseases. In recent decades, the intake of methyl group compounds has changed significantly due to, e.g., environmental pollution and food additives. Based on the current knowledge, this review provides a brief overview of the highly interconnected relationship between nutrition, metabolism, changes in epigenetic modifications, cancer, and aging. One goal is to provide an impetus to additionally investigate changes in DNA methylation as a possible consequence of an impaired methyl group metabolism.
Assuntos
Epigênese Genética , Neoplasias , Envelhecimento/genética , Metilação de DNA , Epigenômica , Humanos , Neoplasias/genéticaRESUMO
Nijmegen Breakage Syndrome (NBS) is a rare autosomal recessive genetic disorder caused by mutations within nibrin (NBN), a DNA damage repair protein. Hallmarks of NBS include chromosomal instability and clinical manifestations such as growth retardation, immunodeficiency, and progressive microcephaly. We employed induced pluripotent stem cell-derived cerebral organoids from two NBS patients to study the etiology of microcephaly. We show that NBS organoids carrying the homozygous 657del5 NBN mutation are significantly smaller with disrupted cyto-architecture. The organoids exhibit premature differentiation, and Neuronatin (NNAT) over-expression. Furthermore, pathways related to DNA damage response and cell cycle are differentially regulated compared to controls. After exposure to bleomycin, NBS organoids undergo delayed p53-mediated DNA damage response and aberrant trans-synaptic signaling, which ultimately leads to neuronal apoptosis. Our data provide insights into how mutations within NBN alters neurogenesis in NBS patients, thus providing a proof of concept that cerebral organoids are a valuable tool for studying DNA damage-related disorders.
Assuntos
Microcefalia , Síndrome de Quebra de Nijmegen , Dano ao DNA , Humanos , Microcefalia/genética , Síndrome de Quebra de Nijmegen/genética , Síndrome de Quebra de Nijmegen/metabolismo , Organoides/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
Epigenetic mechanisms are fundamentally important for cancer initiation and development. However, a survey of the literature reveals that, to date, they appear less comprehensively investigated in melanoma than in many other cancers, e.g., prostate, breast, and colon carcinoma. The aim of this review is to provide a short summary of epigenetic aspects of functional relevance for melanoma pathogenesis. In addition, some new perspectives from epigenetic research in other cancers with potential for melanoma diagnosis and therapy are introduced. For example, the PrimeEpiHit hypothesis in urothelial carcinoma, which, similarly to malignant melanoma, can also be triggered by a single exogenous noxa, states that one of the first steps for cancer initiation could be epigenetic changes in key genes of one-carbon metabolism. The application of such insights may contribute to further progress in the diagnosis and therapy of melanoma, a deadly type of cancer.
Assuntos
Epigênese Genética , Redes Reguladoras de Genes , Melanoma/genética , Metilação de DNA , Detecção Precoce de Câncer , Humanos , Melanoma/diagnóstico , Melanoma/terapiaRESUMO
Kidney diseases, including acute kidney injury (AKI) and chronic kidney disease (CKD), which can progress to end stage renal disease (ESRD), are a worldwide health burden. Organ transplantation or kidney dialysis are the only effective available therapeutic tools. Therefore, in vitro models of kidney diseases and the development of prospective therapeutic options are urgently needed. Within the kidney, the glomeruli are involved in blood filtration and waste excretion and are easily affected by changing cellular conditions. Puromycin aminonucleoside (PAN) is a nephrotoxin, which can be employed to induce acute glomerular damage and to model glomerular disease. For this reason, we generated kidney organoids from three iPSC lines and treated these with PAN in order to induce kidney injury. Morphological observations revealed the disruption of glomerular and tubular structures within the kidney organoids upon PAN treatment, which were confirmed by transcriptome analyses. Subsequent analyses revealed an upregulation of immune response as well as inflammatory and cell-death-related processes. We conclude that the treatment of iPSC-derived kidney organoids with PAN induces kidney injury mediated by an intertwined network of inflammation, cytoskeletal re-arrangement, DNA damage, apoptosis and cell death. Furthermore, urine-stem-cell-derived kidney organoids can be used to model kidney-associated diseases and drug discovery.
Assuntos
Injúria Renal Aguda , Células-Tronco Pluripotentes Induzidas , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/metabolismo , Humanos , Rim , Organoides/metabolismo , Puromicina Aminonucleosídeo/metabolismo , Puromicina Aminonucleosídeo/farmacologiaRESUMO
With approximately 1.4 million men annually diagnosed with prostate cancer (PCa) worldwide, PCa remains a dreaded threat to life and source of devastating morbidity. In recent decades, a significant decrease in age-specific PCa mortality has been achieved by increasing prostate-specific antigen (PSA) screening and improving treatments. Nevertheless, upcoming, augmented recommendations against PSA screening underline an escalating disproportion between the benefit and harm of current diagnosis/prognosis and application of radical treatment standards. Undoubtedly, new potent diagnostic and prognostic tools are urgently needed to alleviate this tensed situation. They should allow a more reliable early assessment of the upcoming threat, in order to enable applying timely adjusted and personalized therapy and monitoring. Here, we present a basic study on an epigenetic screening approach by Methylated DNA Immunoprecipitation (MeDIP). We identified genes associated with hypomethylated CpG islands in three PCa sample cohorts. By adjusting our computational biology analyses to focus on single CpG-enriched 60-nucleotide-long DNA probes, we revealed numerous consistently differential methylated DNA segments in PCa. They were associated among other genes with NOTCH3, CDK2AP1, KLK4, and ADAM15. These can be used for early discrimination, and might contribute to a new epigenetic tumor classification system of PCa. Our analysis shows that we can dissect short, differential methylated CpG-rich DNA fragments and combinations of them that are consistently present in all tumors. We name them tumor cell-specific differential methylated CpG dinucleotide signatures (TUMS).
Assuntos
Metilação de DNA , Neoplasias da Próstata , Humanos , Masculino , Proteínas ADAM/genética , Ilhas de CpG , DNA , Proteínas de Membrana/genética , Antígeno Prostático Específico/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologiaRESUMO
BACKGROUND: Natural amylin is a pancreatic hormone that induces satiety. Cagrilintide is a long-acting amylin analogue under investigation for weight management. We assessed the dose-response relationship of cagrilintide regarding the effects on bodyweight, safety, and tolerability. METHODS: We conducted a multicentre, randomised, double-blind, placebo-controlled and active-controlled, dose-finding phase 2 trial at 57 sites including hospitals, specialist clinics, and primary care centres in ten countries (Canada, Denmark, Finland, Ireland, Japan, Poland, Serbia, South Africa, the UK, and the USA). Eligible participants were adults aged at least 18 years without diabetes, with a body-mass index of at least 30 kg/m2 or at least 27 kg/m2 with hypertension or dyslipidaemia. Participants were randomly assigned (6:1) to subcutaneous self-injections of once-weekly cagrilintide (0·3, 0·6, 1·2, 2·4, or 4·5 mg), once-daily liraglutide 3·0 mg, or volume-matched placebo (for six placebo groups). The trial had a 26-week treatment period, including a dose-escalation period of up to 6 weeks, and a 6-week follow-up period without treatment. Participants and investigators were masked to the assigned study treatment with respect to active versus pooled placebo treatment, but not to different active treatments. The primary endpoint was the percentage change in bodyweight from baseline to week 26, assessed in all randomly assigned participants according to the trial product estimand (assuming all participants were adherent to treatment) and to the treatment policy estimand (regardless of adherence to treatment). Safety was assessed in all participants who received at least one dose of randomised treatment. This trial is registered with ClinicalTrials.gov, NCT03856047, and is closed to new participants. FINDINGS: Between March 1 and Aug 19, 2019, we randomly assigned 706 participants to cagrilintide 0·3-4·5 mg (100-102 per dose group), 99 to liraglutide 3·0 mg, and 101 to placebo. Permanent treatment discontinuation (n=73 [10%]) occurred similarly across treatment groups, mostly due to adverse events (n=30 [4%]). In total, 29 participants (4%) withdrew from the trial. According to the trial product estimand, mean percentage weight reductions from baseline were greater with all doses of cagrilintide (0·3-4·5 mg, 6·0%-10·8% [6·4-11·5 kg]) versus placebo (3·0% [3·3 kg]; estimated treatment difference range 3·0%-7·8%; p<0·001). Weight reductions were also greater with cagrilintide 4·5 mg versus liraglutide 3·0 mg (10·8% [11·5 kg] vs 9·0% [9·6 kg]; estimated treatment difference 1·8%, p=0·03). Similar weight loss reductions were observed with the treatment policy estimand. The most frequent adverse events were gastrointestinal disorders (eg, nausea, constipation, and diarrhoea) and administration-site reactions. More participants receiving cagrilintide 0·3-4·5 mg had gastrointestinal adverse events compared with placebo (41%-63% vs 32%), primarily nausea (20%-47% vs 18%). INTERPRETATION: Treatment with cagrilintide in people with overweight and obesity led to significant reductions in bodyweight and was well tolerated. The findings support the development of molecules with novel mechanisms of action for weight management. FUNDING: Novo Nordisk A/S.
Assuntos
Relação Dose-Resposta a Droga , Polipeptídeo Amiloide das Ilhotas Pancreáticas/uso terapêutico , Obesidade/tratamento farmacológico , Redução de Peso/efeitos dos fármacos , África , Índice de Massa Corporal , Método Duplo-Cego , Europa (Continente) , Feminino , Humanos , Hipoglicemiantes/uso terapêutico , Injeções Subcutâneas , Liraglutida/administração & dosagem , Masculino , Pessoa de Meia-Idade , América do NorteRESUMO
LINE-1 hypomethylation of cell-free DNA has been described as an epigenetic biomarker of human aging. However, in the past, insufficient differentiation between cellular and cell-free DNA may have confounded analyses of genome-wide methylation levels in aging cells. Here we present a new methodological strategy to properly and unambiguously extract DNA methylation patterns of repetitive, as well as single genetic loci from pure cell-free DNA from peripheral blood. Since this nucleic acid fraction originates mainly in apoptotic, senescent and cancerous cells, this approach allows efficient analysis of aged and cancerous cell-specific DNA methylation patterns for diagnostic and prognostic purposes. Using this methodology, we observe a significant age-associated erosion of LINE-1 methylation in cfDNA suggesting that the threshold of hypomethylation sufficient for relevant LINE-1 activation and consequential harmful retrotransposition might be reached at higher age. We speculate that this process might contribute to making aging the main risk factor for many cancers.
Assuntos
Envelhecimento/genética , Ácidos Nucleicos Livres , Metilação de DNA , Epigênese Genética , Epigenômica , Elementos Nucleotídeos Longos e Dispersos , Retroelementos , Adulto , Fatores Etários , Biomarcadores , Epigenômica/métodos , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Regiões Promotoras GenéticasRESUMO
Urothelial carcinoma (UC) is a common disease causing significant morbidity and mortality as well as considerable costs for health systems. Extensive aberrant methylation of DNA is broadly documented in early UC, contributing to genetic instability, altered gene expression and tumor progression. However the triggers initiating aberrant methylation are unknown. Recently we discovered that several genes encoding key enzymes of methyl group and polyamine metabolism, including Ornithine Decarboxylase 1 (ODC1), are affected by DNA methylation in early stage UC. In this study, we investigated the hypothesis that these epigenetic alterations act in a feed-forward fashion to promote aberrant DNA methylation in UC. We demonstrate that siRNA-mediated knockdown of ODC1 expression elicits genome-wide LINE-1 demethylation, induction of LINE-1 transcripts and double-strand DNA breaks and decreases viability in primary cultured uroepithelial cells. Similarly, following siRNA-mediated knockdown of ODC1, UC cells undergo double-strand DNA breaks and apoptosis. Collectively, our findings provide evidence that ODC1 gene hypermethylation could be a starting point for the onset of genome-wide epigenetic aberrations in urothelial carcinogenesis. Furthermore, LINE-1 induction enabled by ODC1 interference provides a new experimental model to study mechanisms and consequences of LINE-1 activation in the etiology and progression of UC as well as presumably other cancers.
Assuntos
Epigênese Genética , Ornitina Descarboxilase/deficiência , Ornitina Descarboxilase/genética , Interferência de RNA , Neoplasias Urológicas/patologia , Urotélio/patologia , Apoptose/genética , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/genética , Humanos , RNA Mensageiro/genética , RNA Interferente Pequeno/genéticaRESUMO
Human urine is a non-invasive source of renal stem cells with regeneration potential. Urine-derived renal progenitor cells were isolated from 10 individuals of both genders and distinct ages. These renal progenitors express pluripotency-associated proteins- TRA-1-60, TRA-1-81, SSEA4, C-KIT and CD133, as well as the renal stem cell markers -SIX2, CITED1, WT1, CD24 and CD106. The transcriptomes of all SIX2+ renal progenitors clustered together, and distinct from the human kidney biopsy-derived epithelial proximal cells (hREPCs). Stimulation of the urine-derived renal progenitor cells (UdRPCs) with the GSK3ß-inhibitor (CHIR99021) induced differentiation. Transcriptome and KEGG pathway analysis revealed upregulation of WNT-associated genes- AXIN2, JUN and NKD1. Protein interaction network identified JUN- a downstream target of the WNT pathway in association with STAT3, ATF2 and MAPK1 as a putative negative regulator of self-renewal. Furthermore, like pluripotent stem cells, self-renewal is maintained by FGF2-driven TGFß-SMAD2/3 pathway. The urine-derived renal progenitor cells and the data presented should lay the foundation for studying nephrogenesis in human.
Assuntos
Autorrenovação Celular/genética , Autorrenovação Celular/fisiologia , Fator 2 de Crescimento de Fibroblastos/fisiologia , Rim/citologia , Células-Tronco Pluripotentes/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta/fisiologia , Urina/citologia , Via de Sinalização Wnt/genética , Via de Sinalização Wnt/fisiologia , Diferenciação Celular/genética , Feminino , Fator 2 de Crescimento de Fibroblastos/metabolismo , Expressão Gênica , Humanos , Masculino , Células-Tronco Pluripotentes/metabolismo , Transcriptoma , Fator de Crescimento Transformador beta/metabolismoRESUMO
Aging associated DNA hypomethylation of LINE-1 and Alu retroelements may be a crucial determinant of loss of genomic integrity, deterioration and cancer. In peripheral blood LINE-1 hypomethylation has been reported to increase during aging, but other studies did not observe significant changes. We hypothesized that these apparently inconsistent reports might relate to differences between cellular and cell-free DNA. Using the technique of idiolocal normalization of real-time methylation-specific PCR (IDLN-MSP) for genetic imbalanced DNA specimens we obtained evidence that LINE-1 hypomethylation in cell-free DNA, but not cellular DNA from peripheral blood is an epigenetic biomarker for human aging. Furthermore, hypomethylation of cell-free DNA is more extensive in smokers, suggesting that it might be used as a surrogate marker for monitoring the improvement of smoking-induced adverse effects after cancelling smoking.
RESUMO
A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
RESUMO
Urothelial carcinoma (UC), the most common cancer of the urinary bladder causes severe morbidity and mortality, e.g. about 40.000 deaths in the EU annually, and incurs considerable costs for the health system due to the need for prolonged treatments and long-term monitoring. Extensive aberrant DNA methylation is described to prevail in urothelial carcinoma and is thought to contribute to genetic instability, altered gene expression and tumor progression. However, it is unknown how this epigenetic alteration arises during carcinogenesis. Intact methyl group metabolism is required to ensure maintenance of cell-type specific methylomes and thereby genetic integrity and proper cellular function. Here, using two independent techniques for detecting DNA methylation, we observed DNA hypermethylation of the 5'-regulatory regions of the key methyl group metabolism genes ODC1, AHCY and MTHFR in early urothelial carcinoma. These hypermethylation events are associated with genome-wide DNA hypomethylation which is commonly associated with genetic instability. We therefore infer that hypermethylation of methyl group metabolism genes acts in a feed-forward cycle to promote additional DNA methylation changes and suggest a new hypothesis on the molecular etiology of urothelial carcinoma.
Assuntos
Carcinogênese/genética , Metilação de DNA/genética , Neoplasias Urológicas/genética , Urotélio/metabolismo , Carcinoma de Células de Transição , Epigênese Genética , Feminino , Humanos , Masculino , Proteínas de Neoplasias/genética , Regiões Promotoras Genéticas , Fatores de Risco , Neoplasias Urológicas/metabolismo , Neoplasias Urológicas/patologia , Urotélio/patologiaRESUMO
BACKGROUND AND OBJECTIVES: Degarelix is a gonadotropin-releasing hormone antagonist registered for the treatment of advanced hormone-dependent prostate cancer. Treatment causing androgen deprivation is associated with QT prolongation and this study investigated whether degarelix at supratherapeutic concentrations has an intrinsic effect per se on cardiac repolarisation and the QT interval. METHODS: This was a single-centre, randomised, crossover study comparing the effect of degarelix, placebo, and the positive control moxifloxacin on the QT interval. Degarelix and placebo treatments were double-blind, whereas moxifloxacin treatment was open-label. Eighty healthy men, aged 18-45 years, received single intravenous doses of degarelix 2.8 mg, and placebo, as well as a single oral dose of moxifloxacin 400 mg. Electrocardiograms were collected up to 24 h after the start of administration, with the QT interval assessed and plasma concentrations of degarelix concomitantly analysed. RESULTS: Time-matched, one-sided 95% upper confidence boundaries for baseline-corrected average changes from placebo for the QT interval, corrected using the Fridericia method (ΔΔQTcF), did not exceed 10 ms at any timepoint, with maximum degarelix concentrations reaching approximately threefold the concentrations seen in the treatment of prostate cancer. Furthermore, concentration-exposure analysis indicated absence of any QT prolongation effects of degarelix. No significant effect on any other cardiac parameter was observed. The lower bound of the 98.3% confidence interval for moxifloxacin ΔΔQTcF exceeded 5 ms, thus verifying assay sensitivity. CONCLUSION: The results showed that the study was validated to detect a significant effect on the QT interval, and that degarelix by itself does not have any effect on the QT interval and cardiac repolarisation at supratherapeutic concentrations.
Assuntos
Síndrome do QT Longo/induzido quimicamente , Oligopeptídeos/efeitos adversos , Receptores LHRH/antagonistas & inibidores , Adolescente , Adulto , Estudos Cross-Over , Método Duplo-Cego , Eletrocardiografia , Fluoroquinolonas/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Moxifloxacina , Adulto JovemRESUMO
Epigenetic mechanisms such as DNA methylation are increasingly recognized to be critical for vaccination efficacy and outcome of different infectious diseases, but corresponding information is scarcely available for host defense against malaria. In the experimental blood-stage malaria Plasmodium chabaudi, we investigate the possible effects of a blood-stage vaccine on DNA methylation of gene promoters in the liver, known as effector against blood-stage malaria, using DNA methylation microarrays. Naturally susceptible Balb/c mice acquire, by protective vaccination, the potency to survive P. chabaudi malaria and, concomitantly, modifications of constitutive DNA methylation of promoters of numerous genes in the liver; specifically, promoters of 256 genes are hyper(=up)- and 345 genes are hypo(=down)-methylated (p < 0.05). Protective vaccination also leads to changes in promoter DNA methylation upon challenge with P. chabaudi at peak parasitemia on day 8 post infection (p.i.), when 571 and 1013 gene promoters are up- and down-methylated, respectively, in relation to constitutive DNA methylation (p < 0.05). Gene set enrichment analyses reveal that both vaccination and P. chabaudi infections mainly modify promoters of those genes which are most statistically enriched with functions relating to regulation of transcription. Genes with down-methylated promoters encompass those encoding CX3CL1, GP130, and GATA2, known to be involved in monocyte recruitment, IL-6 trans-signaling, and onset of erythropoiesis, respectively. Our data suggest that vaccination may epigenetically improve parts of several effector functions of the liver against blood-stage malaria, as, e.g., recruitment of monocyte/macrophage to the liver accelerated liver regeneration and extramedullary hepatic erythropoiesis, thus leading to self-healing of otherwise lethal P. chabaudi blood-stage malaria.