Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 605
Filtrar
1.
Mol Nutr Food Res ; : e2300831, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602198

RESUMO

SCOPE: The excretion of dietary odorants into urine and milk is evaluated and the impact of possible influencing factors determined. Furthermore, the metabolic relevance of conjugates for the excretion into milk is investigated. METHODS AND RESULTS: Lactating mothers (n = 20) are given a standardized curry dish and donated one milk and urine sample each before and 1, 2, 3, 4.5, 6, and 8 h after the intervention. The concentrations of nine target odorants in these samples are determined. A significant transition is observed for linalool into milk, as well as for linalool, cuminaldehyde, cinnamaldehyde, and eugenol into urine. Maximum concentrations are reached within 1 h after the intervention in the case of milk and within 2-3 h in the case of urine. In addition, the impact of glucuronidase treatment on odorant concentrations is evaluated in a sample subset of twelve mothers. Linalool, eugenol, and vanillin concentrations increased 3-77-fold in milk samples after treatment with ß-glucuronidase. CONCLUSION: The transfer profiles of odorants into milk and urine differ qualitatively, quantitatively, and in temporal aspects. More substances are transferred into urine and the transfer needs a longer period compared with milk. Phase II metabolites are transferred into urine and milk.

2.
Trends Cancer ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38503638

RESUMO

Pathogenic variants (PVs) in DNA repair-linked adult-onset cancer predisposition genes, including double heterozygosity, are increasingly identified in pediatric patients with cancer. Their role in childhood cancer, however, remains poorly understood. Integrating comprehensive tumor analysis is integral for understanding the contribution of such PVs in cancer development and personalized cancer care.

3.
J Agric Food Chem ; 72(1): 1-3, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38197191
4.
Mol Nutr Food Res ; 68(1): e2300396, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37953385

RESUMO

SCOPE: For most substances, there are several routes of excretion from the human body. This study focuses on urinary excretion of dietary odorants and compares the results with previously obtained results on excretion into milk. METHODS AND RESULTS: Lactating mothers (n = 18) are given a standardized curry dish and donate urine samples before and after the intervention. The odorants 1,8-cineole, linalool, cuminaldehyde, cinnamaldehyde, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, sotolone, eugenol, vanillin, and γ-nonalactone are quantitatively analyzed. A significant transition of up to 6 µg g-1 creatinine into urine is observed for linalool, 1,8-cineole, and eugenol. Maximum concentrations are reached 1.5 h after the intervention for 1,8-cineole and eugenol as well as 2.5 h after the intervention for linalool. Comparison with previous results reveals that the excretion pattern of odorants into urine is divergent from the one into milk. In a second intervention study (n = 6), excretion of phase II metabolites into urine is studied using ß-glucuronidase treatment. Linalool and eugenol concentrations are 23 and 77 times higher after treatment than before treatment with ß-glucuronidase, respectively. CONCLUSION: The study demonstrates transition of linalool, 1,8-cineole, and eugenol from the diet into urine and excretion of glucuronides in the case of linalool, eugenol, and vanillin.


Assuntos
Eugenol , Lactação , Feminino , Humanos , Eucaliptol , Glucuronidase
5.
J Agric Food Chem ; 71(50): 20243-20250, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38084639

RESUMO

Because food flavor is perceived through a combination of odor and taste, an analytical method that covers both dimensions would be very beneficial for mapping the consistent product quality over the entirety of a manufacturing process. Such a method, so-called "unified flavor quantitation", has been successfully applied to several different food products in recent years. The simultaneous detection of aroma and taste compounds by means of ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) enables the analysis and quantification of an enormously large number of compounds in a single run. To evaluate the limits of this method, chocolate, a high-fat, complex matrix, was selected. In 38 distinct commercial chocolate samples, 20 flavor-active acids, aldehydes, and sugars were analyzed after a simple, rapid extraction step followed by derivatization with 3-nitrophenylhydrazine using a single UHPLC-MS/MS method. The results obtained highlight the great potential of the "unified flavor quantitation" approach and demonstrate the possibility of high-throughput quantitation of key aroma- and taste-active molecules in a single assay.


Assuntos
Cacau , Chocolate , Chocolate/análise , Espectrometria de Massas em Tandem , Cacau/química , Odorantes/análise , Cromatografia Líquida de Alta Pressão , Paladar
6.
Pleura Peritoneum ; 8(3): 113-121, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37662605

RESUMO

Objectives: Cytoreductive surgery (CRS) and heated intraperitoneal chemotherapy (HIPEC) is associated with significant postoperative complications. Early detection of at-risk patients may lead to improved outcomes. The role of C-reactive protein (CRP) in predicting postoperative complications has only been recently investigated. Methods: Postoperative complications were categorized according to Clavien-Dindo classification and further divided into minor (Grade <3) and major complications (Grade ≥3A). Absolute CRP counts (mg/L) on postoperative days (POD) 1-7, and proportional change in CRP was compared and the area under (AUC) receiver operating characteristics (ROC) curve was calculated. Univariate and multivariate analysis was performed. Significant findings were externally validated. Results: Twenty-five percent of patients experienced one or more major complications. A CRP level of ≥106 mg/L on POD 2 and 65.5 mg/L on POD 4 were significantly associated with an increased risk of major complications with an AUC of 0.658 and 0.672, respectively. The proportional increase in CRP between POD 1 and 4 (ΔCRP POD 1/4) at a cut-off of 30 % had the best AUC of 0.744 and was the only independent risk factor for major complications (p<0.0001) on multivariate analysis. ∆CRP had an AUC of 0.716 (p=0.002) when validated in an independent database. Conclusions: CRP can be used in a variety of ways to predict major complications after CRS and HIPEC. However, the ∆CRP POD 1/4>30 % is the best indicator of major complications. Serial CRP measurements in the early postoperative period may lead to early detection of patients at risk of major complications allowing for alternative management strategies to improve outcomes.

8.
J Smooth Muscle Res ; 59: 34-57, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37407438

RESUMO

Garcinia buchananii stem bark extract (GBB), commonly used for treating diarrhea in Africa, triggers ectopic aboral contractions, causing inhibition of propulsive motility in the colon ex vivo. To determine whether or not these effects were associated with decreased inhibitory neuromuscular transmission, the responsible constituent compounds, and mechanisms of action, we studied the effects of GBB and specific fractions and flavanones isolated from GBB on intestinal motility using pellet propulsion assays in guinea pig distal colons. In addition, microelectrode recordings were used to measure the effects on the inhibitory junction potentials (IJPs) in the porcine ileum and descending colon smooth muscle. Psychoactive Drug Screening Program secondary receptor functional assays were used to determine whether or not GBB and its constituent compounds act via purinergic (P2Y) and muscarinic receptors. GBB inhibited propulsive motility, but (2R,3S,2″R,3″R)-manniflavanone (MNF), (2R,3S,2″R,3″R)-GB-2 (GB-2) and (2R,3S,2″S)-buchananiflavanone (BNF), the main ingredients of GBB, did not affect motility. We discovered that, in the porcine descending colon, IJPs contained purinergic, nitrergic, and nonpurinergic nonnitrergic components. Furthermore, ileal IJPs were purely purinergic. GBB blocked all components of IJPs, while MNF and GB-2 inhibited purinergic IJPs only. BNF inhibited the purinergic and nonpurinergic components of IJPs. MRS2365, a Y1 (P2Y) agonist, did not evoke sustained membrane hyperpolarization in the presence of GBB. However, GBB, MNF, GB-2 and BNF did not affect P2Y or muscarinic receptors. In conclusion, inhibitory neuromuscular transmission in the porcine descending colon involves all components of IJPs. GBB decreases inhibitory neuromuscular transmission, likely by the actions of MNF, GB-2 and BNF. These effects do not involve P2Y or muscarinic receptors.


Assuntos
Flavonas , Garcinia , Animais , Cobaias , Casca de Planta , Colo , Flavonas/farmacologia
9.
J Adv Res ; 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37467961

RESUMO

INTRODUCTION: Posttranslational modification of proteins by reversible acetylation regulates key biological processes. Histone deacetylases (HDACs) catalyze protein deacetylation and are frequently dysregulated in tumors. This has spurred the development of HDAC inhibitors (HDACi). Such epigenetic drugs modulate protein acetylation, eliminate tumor cells, and are approved for the treatment of blood cancers. OBJECTIVES: We aimed to identify novel, nanomolar HDACi with increased potency over existing agents and selectivity for the cancer-relevant class I HDACs (HDAC1,-2,-3,-8). Moreover, we wanted to define how such drugs control the apoptosis-autophagy interplay. As test systems, we used human leukemic cells and embryonic kidney-derived cells. METHODS: We synthesized novel pyrimidine-hydroxamic acid HDACi (KH9/KH16/KH29) and performed in vitro activity assays and molecular modeling of their direct binding to HDACs. We analyzed how these HDACi affect leukemic cell fate, acetylation, and protein expression with flow cytometry and immunoblot. The publicly available DepMap database of CRISPR-Cas9 screenings was used to determine sensitivity factors across human leukemic cells. RESULTS: Novel HDACi show nanomolar activity against class I HDACs. These agents are superior to the clinically used hydroxamic acid HDACi SAHA (vorinostat). Within the KH-series of compounds, KH16 (yanostat) is the most effective inhibitor of HDAC3 (IC50 = 6 nM) and the most potent inducer of apoptosis (IC50 = 110 nM; p < 0.0001) in leukemic cells. KH16 though spares embryonic kidney-derived cells. Global data analyses of knockout screenings verify that HDAC3 is a dependency factor in 115 human blood cancer cells of different lineages, independent of mutations in the tumor suppressor p53. KH16 alters pro- and anti-apoptotic protein expression, stalls cell cycle progression, and induces caspase-dependent processing of the autophagy proteins ULK1 and p62. CONCLUSION: These data reveal that HDACs are required to stabilize autophagy proteins through suppression of apoptosis in leukemic cells. HDAC3 appears as a valid anti-cancer target for pharmacological intervention.

10.
Neuropathol Appl Neurobiol ; 49(4): e12915, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37296499

RESUMO

AIMS: Nijmegen breakage syndrome (NBS) is a rare autosomal recessive disorder caused by hypomorphic mutations of NBS1. NBS1 is a member of the MRE11-RAD50-NBS1 (MRN) complex that binds to DNA double-strand breaks and activates the DNA damage response (DDR). Nbs1 inactivation in neural progenitor cells leads to microcephaly and premature death. Interestingly, p53 homozygous deletion rescues the NBS1-deficient phenotype allowing long-term survival. The objective of this work was to determine whether simultaneous inactivation of Nbs1 and p53 in neural progenitors triggered brain tumorigenesis and if so in which category this tumour could be classified. METHODS: We generated a mouse model with simultaneous genetic inactivation of Nbs1 and p53 in embryonic neural stem cells and analysed the arising tumours with in-depth molecular analyses including immunohistochemistry, array comparative genomic hybridisation (aCGH), whole exome-sequencing and RNA-sequencing. RESULTS: NBS1/P53-deficient mice develop high-grade gliomas (HGG) arising in the olfactory bulbs and in the cortex along the rostral migratory stream. In-depth molecular analyses using immunohistochemistry, aCGH, whole exome-sequencing and RNA-sequencing revealed striking similarities to paediatric human HGG with shared features with radiation-induced gliomas (RIGs). CONCLUSIONS: Our findings show that concomitant inactivation of Nbs1 and p53 in mice promotes HGG with RIG features. This model could be useful for preclinical studies to improve the prognosis of these deadly tumours, but it also highlights the singularity of NBS1 among the other DNA damage response proteins in the aetiology of brain tumours.


Assuntos
Glioma , Proteína Supressora de Tumor p53 , Animais , Criança , Humanos , Camundongos , Proteínas de Ciclo Celular/genética , Glioma/genética , Homozigoto , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Deleção de Sequência , Proteína Supressora de Tumor p53/genética
11.
Foods ; 12(9)2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37174415

RESUMO

Sustainability, low toxicity, and high solute potential are the fundamental reasons for focusing green chemistry on natural deep eutectic solvents (NADES). The application of NADES ranges from organic chemistry to the agricultural sector and the food industry. In the food industry, the desired food quality can be achieved by the extraction of small molecules, macromolecules, and even heavy metals. The compound yield in Maillard-type model reactions can also be increased using NADES. To extend the so-called "kitchen-type chemistry" field, an inert, food-grade NADES system based on sucrose/D-sorbitol was developed, characterized, and examined for its ability as a reaction medium by evaluating its temperature and pH stability. Reaction boundary conditions were determined at 100 °C for three hours with a pH range of 3.7-9.0. As proof of principle, two Maillard-type model reactions were implemented to generate the taste-modulating compounds N2-(1-carboxyethyl)guanosine 5'-monophosphate) (161.8 µmol/mmol) and N2-(furfuryl thiomethyl)guanosine 5'-monophosphate (95.7 µmol/g). Since the yields of both compounds are higher than their respective taste-modulating thresholds, the newly developed NADES is well-suited for these types of "kitchen-type chemistry" and, therefore, a potential solvent candidate for a wide range of applications in the food industry.

12.
J Agric Food Chem ; 71(22): 8633-8647, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37232935

RESUMO

Amino acids and acylcarnitines are important biomarkers of the body's energy state and can be used as diagnostic markers of certain inborn errors of metabolism. Few multianalyte methods for high-throughput analysis in serum exist for these compounds, but micromethods suitable for use in young children and infants are lacking. Therefore, we developed a quantitative high-throughput multianalyte hydrophilic interaction liquid chromatography-tandem mass spectrometry method preceded by a derivatization-free sample preparation using minimum amounts of serum (25 µL). Isotopically labeled standards were utilized for quantification. Forty amino acids and amino acid derivatives and 22 acylcarnitines were detected by applying a multiple reaction monitoring mode within a 20 min run. The method was comprehensively validated, comprising linearity, accuracy, (intraday/interday) precision, and quantitation limits, of which the latter ranged from 0.25 to 50 nM for acylcarnitines and from 0.005 to 1 µM for amino acids and their derivatives. Application of the method to 145 serum samples of three- to four-month-old healthy infants showed excellent reproducibility for multiday analyses and enabled simultaneous amino acid and acylcarnitine profiling in this age group.


Assuntos
Aminoácidos , Espectrometria de Massas em Tandem , Criança , Lactente , Humanos , Pré-Escolar , Aminoácidos/metabolismo , Espectrometria de Massas em Tandem/métodos , Reprodutibilidade dos Testes , Carnitina
13.
Artigo em Alemão | MEDLINE | ID: mdl-37197614

RESUMO

Background: The determination of incapacity to work is a central approach for analyses of absence due to sickness. Nevertheless, no data are yet available for incapacity to work and associated factors in the German prehospital emergency medical services (EMS) staff. Objective: The aim of this analysis was to identify the proportion of EMS staff with at least one incapacity for work (AU) in the previous 12 months and associated factors. Material and methods: This was a nationwide survey study with rescue workers. Factors associated with work disability were identified using multivariable logistic regression, calculating odds ratios (OR) and associated 95% confidence intervals (95% CI). Results: Included in this analysis were 2298 employees of the German emergency medical services (female 42.6%, male 57.2%). Overall, 60.10% of female participants and 58.98% of male participants reported an incapacity for work in the previous 12 months. Incapacity for work was significantly associated with having a high school diploma (high school diploma: OR: 0.51, 95% CI 0.30; 0.88, p = 0.016; reference: secondary school diploma), working in a rural environment (OR: 0.65, 95% CI 0.50; 0.86, p = 0.003) or urban environment (OR: 0.72, 95% CI: 0.53; 0.98, p = 0.037). Furthermore, hours worked per week (OR: 1.01, 95% CI: 1.00; 1.02, p = 0.003) and 5-< 10 years of service (OR: 1.40, 95% CI: 1.04; 1.89, p = 0.025) were associated with higher odds of work disability. Neck and back pain, depression, osteoarthritis, and asthma in the previous 12 months also showed a significant association with work disability in the same time period. Conclusion: This analysis shows that chronic diseases, educational attainment, area of assignment, years of service, and hours worked per week, among others, were associated with incapacity for work in the previous 12 months in German EMS staff.

14.
J Agric Food Chem ; 71(22): 8622-8632, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37228041

RESUMO

Recent studies show the immense capacities of the unified quantitation of aroma and taste compounds using liquid chromatography-mass spectrometry (LC-MS). The goal of this study was to highlight the broad application of this unified method. Thus, a stable isotope dilution analysis quantification method of the most important key food odorants in various food categories by LC-MS was developed. Using the well-known derivatization agent 3-nitrophenylhydrazine for carbonyl derivatization and a newly developed approach for alcohol and thiol derivatization, a method for the quantitation of 20 key food odorants was established. Intraday precision was determined to be ≤26%, and interday precision was between 24 and 31%. Limits of quantitation were determined between 0.014 and 283 µg/kg. The work shows that a wide array of aroma compounds can be analyzed accurately by LC-MS.


Assuntos
Odorantes , Compostos Orgânicos Voláteis , Odorantes/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Compostos Orgânicos Voláteis/química
15.
Surgery ; 174(2): 189-195, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37246126

RESUMO

BACKGROUND: Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy is a curative treatment for selected patients with peritoneal surface malignancy. Reaching actual outcomes benchmarks is challenging given the complex nature of peritoneal surface malignancy surgery. The aim of this study was to assess how the benchmarks for morbidity and oncologic outcome can be reached at a newly established program for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. METHODS: Building on existing institutional experience in complex abdominal surgery and interdisciplinary ovarian cancer treatment, a peritoneal surface malignancy center for cytoreductive surgery and hyperthermic intraperitoneal chemotherapy was established at the Medical University of Vienna using a structured mentoring process. This is a retrospective analysis of the first 100 consecutive patients. Morbidity and mortality were assessed using the Clavien-Dindo classification, and oncologic outcomes using overall survival. RESULTS: Major morbidity and mortality were 26% and 3%, and median overall survival was 49.0 months. In patients with colorectal peritoneal metastases, the median overall survival was 35.1 months (all colorectal peritoneal metastases patients) and 48.8 months in the subgroup with Peritoneal Surface Disease Severity Score ≤3. No median overall survival could be calculated in patients with low-grade appendiceal mucinous neoplasms, appendiceal adenocarcinoma, or peritoneal mesothelioma due to >50% of patients being alive at the end of follow-up. CONCLUSION: We show that the current morbidity and oncological outcomes benchmarks can be reached within the first 100 cases of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy at a newly established peritoneal surface malignancy center. Previous institutional experience in complex abdominal surgery and a structured mentoring process are key factors in achieving this goal.


Assuntos
Neoplasias do Apêndice , Neoplasias Colorretais , Hipertermia Induzida , Neoplasias Peritoneais , Feminino , Humanos , Neoplasias Peritoneais/cirurgia , Procedimentos Cirúrgicos de Citorredução , Estudos Retrospectivos , Benchmarking , Neoplasias do Apêndice/patologia , Terapia Combinada , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/patologia , Taxa de Sobrevida
16.
Nutrients ; 15(5)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36904259

RESUMO

BACKGROUND: Non-nutritive sweeteners (NNS) are part of personalized nutrition strategies supporting healthy glycemic control. In contrast, the consumption of non-nutritive sweeteners has been related to person-specific and microbiome-dependent glycemic impairments. Reports on the effects of NNS on our highly individual cellular immune system are sparse. The recent identification of taste receptor expression in a variety of immune cells, however, suggested their immune-modulatory relevance. METHODS: We studied the influence of a beverage-typical NNS system on the transcriptional profiling of sweetener-cognate taste receptors, selected cytokines and their receptors, and on Ca2+ signaling in isolated blood neutrophils. We determined plasma concentrations of saccharin, acesulfame-K, and cyclamate by HPLC-MS/MS, upon ingestion of a soft drink-typical sweetener surrogate. In an open-labeled, randomized intervention study, we determined pre- versus post-intervention transcript levels by RT-qPCR of sweetener-cognate taste receptors and immune factors. RESULTS: Here we show that the consumption of a food-typical sweetener system modulated the gene expression of cognate taste receptors and induced the transcriptional regulation signatures of early homeostasis- and late receptor/signaling- and inflammation-related genes in blood neutrophils, shifting their transcriptional profile from homeostasis to priming. Notably, sweeteners at postprandial plasma concentrations facilitated fMLF (N-formyl-Met-Leu-Phe)-induced Ca2+ signaling. CONCLUSIONS: Our results support the notion of sweeteners priming neutrophils to higher alertness towards their adequate stimuli.


Assuntos
Adoçantes não Calóricos , Edulcorantes , Humanos , Aditivos Alimentares , Homeostase , Neutrófilos , Espectrometria de Massas em Tandem
17.
J Chem Inf Model ; 63(7): 2014-2029, 2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-36696962

RESUMO

With approximately 400 encoding genes in humans, odorant receptors (ORs) are the largest subfamily of class A G protein-coupled receptors (GPCRs). Despite its high relevance and representation, the odorant-GPCRome is structurally poorly characterized: no experimental structures are available, and the low sequence identity of ORs to experimentally solved GPCRs is a significant challenge for their modeling. Moreover, the receptive range of most ORs is unknown. The odorant receptor OR5K1 was recently and comprehensively characterized in terms of cognate agonists. Here, we report two additional agonists and functional data of the most potent compound on two mutants, L1043.32 and L2556.51. Experimental data was used to guide the investigation of the binding modes of OR5K1 ligands into the orthosteric binding site using structural information from AI-driven modeling, as recently released in the AlphaFold Protein Structure Database, and from homology modeling. Induced-fit docking simulations were used to sample the binding site conformational space for ensemble docking. Mutagenesis data guided side chain residue sampling and model selection. We obtained models that could better rationalize the different activity of active (agonist) versus inactive molecules with respect to starting models and also capture differences in activity related to minor structural differences. Therefore, we provide a model refinement protocol that can be applied to model the orthosteric binding site of ORs as well as that of GPCRs with low sequence identity to available templates.


Assuntos
Receptores Odorantes , Humanos , Receptores Odorantes/genética , Receptores Odorantes/química , Receptores Odorantes/metabolismo , Odorantes , Receptores Acoplados a Proteínas G/química , Sítios de Ligação , Proteínas de Ligação ao GTP/metabolismo , Ligantes
18.
J Agric Food Chem ; 71(1): 1-4, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36628585
19.
Nucleic Acids Res ; 51(2): 687-711, 2023 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-36629267

RESUMO

The DNA damage response (DDR) is essential to maintain genome stability, and its deregulation predisposes to carcinogenesis while encompassing attractive targets for cancer therapy. Chromatin governs the DDR via the concerted interplay among different layers, including DNA, histone post-translational modifications (hPTMs) and chromatin-associated proteins. Here, we employ multi-layered proteomics to characterize chromatin-mediated functional interactions of repair proteins, signatures of hPTMs and the DNA-bound proteome during DNA double-strand break (DSB) repair at high temporal resolution. Our data illuminate the dynamics of known and novel DDR-associated factors both at chromatin and at DSBs. We functionally attribute novel chromatin-associated proteins to repair by non-homologous end-joining (NHEJ), homologous recombination (HR) and DSB repair pathway choice. We reveal histone reader ATAD2, microtubule organizer TPX2 and histone methyltransferase G9A as regulators of HR and involved in poly-ADP-ribose polymerase-inhibitor sensitivity. Furthermore, we distinguish hPTMs that are globally induced by DNA damage from those specifically acquired at sites flanking DSBs (γH2AX foci-specific) and profiled their dynamics during the DDR. Integration of complementary chromatin layers implicates G9A-mediated monomethylation of H3K56 in DSBs repair via HR. Our data provide a dynamic chromatin-centered view of the DDR that can be further mined to identify novel mechanistic links and cell vulnerabilities in DSB repair.


Assuntos
Cromatina , Histonas , Cromatina/genética , Histonas/metabolismo , Proteômica , Reparo do DNA , Reparo do DNA por Junção de Extremidades , DNA , Reparo de DNA por Recombinação
20.
Clin Chim Acta ; 538: 53-59, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36375525

RESUMO

BACKGROUND AND AIMS: Systemic chemotherapy followed by hepatic resection is the treatment of choice for patients with colorectal cancer liver metastasis (CRCLM) but reliable biomarkers predicting response to therapy are needed. Spontaneous apoptosis of single tumour cells is common in CRCLM. We explored the potential of circulating apoptosis markers to predict treatment response. MATERIALS AND METHODS: Fifty-eight patients with CRCLM or hepatocellular carcinoma (HCC) were included in this study. Tumour tissue and blood samples were obtained before and after initiation of chemotherapy. Immunohistochemistry and ELISA assays were utilized to quantify the apoptosis marker caspase-cleaved cytokeratin 18 (M30) in tissue and circulation. RESULTS: CRCLM tissues showed more apoptotic tumour cells than HCC, or healthy liver. This was associated with elevated levels of circulating M30 (median = 244 U/l vs. 37 U/l in healthy controls, p = 0.009) which correlated with tumour volume (r2 = 0.92). Patients with progressive disease during chemotherapy showed higher M30 levels before therapy than responders (745 U/l vs. 136 U/l, p = 0.016). The predictive potential of M30 was higher than that of the tumour markers CA19-9 or CEA (AUC: 0.93, 0.63, and 0.78, respectively). CONCLUSIONS: Apoptotic tumour cells release cellular debris into the circulation, which provides information about tumour size and vitality.


Assuntos
Carcinoma Hepatocelular , Neoplasias Colorretais , Neoplasias Hepáticas , Humanos , Apoptose , Biomarcadores Tumorais , Caspases , Neoplasias Colorretais/tratamento farmacológico , Queratina-18 , Neoplasias Hepáticas/tratamento farmacológico , Carga Tumoral
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...