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1.
Sci Rep ; 14(1): 24185, 2024 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-39406807

RESUMO

The primary role of telomerase is the lengthening of telomeres. Nonetheless, emerging evidence highlights additional functions of telomerase outside of the nucleus. Specifically, its catalytic subunit, TERT (Telomerase Reverse Transcriptase), is detected in the cytosol and mitochondria. Several studies have suggested an elevation in TERT concentration within mitochondria in response to oxidative stress. However, the origin of this mitochondrial TERT, whether transported from the nucleus or synthesized de novo, remains uncertain. In this study, we investigate the redistribution of TERT, labeled with a SNAP-tag, in response to oxidative stress using laser scanning fluorescence microscopy. Our findings reveal that, under our experimental conditions, there is no discernible transport of TERT from the nucleus to the mitochondria due to oxidative stress.


Assuntos
Mitocôndrias , Estresse Oxidativo , Telomerase , Telomerase/metabolismo , Mitocôndrias/metabolismo , Humanos , Núcleo Celular/metabolismo , Transporte Proteico
2.
Ann Surg Oncol ; 2024 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-39422848

RESUMO

BACKGROUND: Talimogene laherparapvec (T-VEC) is a modified herpes simplex virus type 1 (HSV-1) and the first oncolytic virus to be approved for the treatment of unresectable melanoma. We assessed whether there are tumor-intrinsic genetic factors that are associated with tumor control. METHODS: A single-institution, retrospective analysis of melanoma patients treated with T-VEC was performed. Demographics, histopathologic reports, treatment history, clinical outcomes, and tumor genomic analysis of approximately 100 genes were collected. RESULTS: Ninety-three patients who had received T-VEC were identified, of whom 84 (91%) were diagnosed with cutaneous melanoma. Sixty-nine (69) patients received more than one dose of T-VEC and had sufficient data available for clinical analysis. Of these patients 30.0% (n = 21) had evidence of a complete response, defined as complete regression of all lesions without the need for additional treatment or procedures. Stage III disease (p < 0.001), absence of macroscopic nodal disease (p < 0.001), and absence of visceral/central nervous system metastases (p = 0.004) were all associated with evidence of any clinical response or local control by univariate analysis. At the time of analysis, 54 patients had tumor genetic data available. Sixty genes were mutated in at least one patient, and all but one patient had at least one gene mutation identified. Presence of TERT promotor mutation was associated with evidence of any clinical response (p = 0.043) or local control (p = 0.039) by multivariate analysis. CONCLUSIONS: This work describes the experience using T-VEC in melanoma at a single institution and highlights the presence of TERT promotor mutations as a possible driver of clinical response.

3.
Lab Invest ; : 102146, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39357799

RESUMO

Solitary fibrous tumor (SFT) is a rare mesenchymal neoplasm which can arise at any anatomic site and is characterized by recurrent NAB2::STAT6 fusions and metastatic progression in 10-30%. The cell of origin has not been identified. Despite some progress in understanding the contribution of heterogeneous fusion types and secondary mutations to SFT biology, epigenetic alterations in extrameningeal SFT remain largely unexplored, and most sarcoma research to date has focused on the use of methylation profiling for tumor classification. We interrogated genome-wide DNA methylation in 79 SFTs to identify informative epigenetic changes. RNA-seq data from targeted panels and data from the Cancer Genome Atlas (TCGA) were used for orthogonal validation of selected findings. In unsupervised clustering analysis, the top 500 most variable CpGs segregated SFTs by primary anatomic site. Differentially methylated genes (DMGs) associated with primary SFT site included EGFR, TBX15, multiple HOX genes and their cofactors EBF1, EBF3, and PBX1, as well as RUNX1 and MEIS1. Of the 20 DMGs that were interrogated on the RNA-seq panel, twelve were significantly differentially expressed according to site. However, with the exception of TBX15, most of these also showed differential expression according to NAB2::STAT6 fusion type, suggesting that the fusion oncogene contributes to transcriptional regulation of these genes. Transcriptomic data confirmed an inverse correlation between gene methylation and the expression of TBX15 in both SFT and TCGA sarcomas. TBX15 also showed differential mRNA expression and 5' UTR methylation between tumors located in different anatomic sites in TCGA data. In all analyses, TBX15 methylation and mRNA expression retained the strongest association with tissue of origin in SFT and other sarcomas, suggesting a possible marker to distinguish metastatic tumors from new primaries without genomic profiling. Epigenetic signatures may further help to identify SFT progenitor cells at different anatomic sites.

4.
J Food Sci ; 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39366771

RESUMO

Harvested longan fruit is prone to pericarp browning, which restricts preservation quality and shortens fruit shelf life. The antioxidant system can defend against oxidative stress-mediated quality deterioration such as fruit browning. This study aimed to evaluate the effect of tert-butylhydroquinone (TBHQ) on anti-browning ability of longan fruit in association with redox metabolism. The results indicated that the application of 0.02% TBHQ significantly suppressed the progression of pericarp browning. In comparison with control, TBHQ treatment decreased the contents of hydrogen peroxide (H2O2), superoxide radical (O2 -⋅), and malondialdehyde, and retained high levels of ascorbic acid (AsA), glutathione (GSH), total phenolics as well as 1,1-diphenyl-2-picrylhydrazyl scavenging rate. Enhanced enzymatic activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR), monodehydroascorbate reductase, and dehydroascorbate reductase (DHAR), but decreased activities of polyphenol oxidase and peroxidase were also observed in TBHQ-treated fruit. Gene expression analysis indicated that redox metabolism-related genes, including DlSOD, DlCAT, DlGR, and DlAPX, were upregulated after TBHQ treatment. Correlation analysis suggested that antioxidants, including AsA, GSH, CAT, APX, SOD, and DHAR, were negatively correlated to reactive oxygen species production and percarp browning. These results suggest that TBHQ is effective in alleviating pericarp browning by increasing antioxidant capacity of longan fruit.

5.
Front Immunol ; 15: 1465006, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39376566

RESUMO

Immunosenescence impacts both the innate and adaptive immune systems, predominantly affecting certain immune cell types. A notable manifestation of immunosenescence is the diminished efficacy of adaptive immunity. The excessive senescence of immune cells, particularly T cells, leads to marked immune deficiency, consequently escalating the risk of infections, tumors, and age-associated disorders. Lymphocytes, especially T cells, are subject to both replicative and premature senescence. Telomerase reverse transcriptase (TERT) and telomerase have multifaceted roles in regulating cellular behavior, possessing the ability to counteract both replicative and premature senescence in lymphocytes. This review encapsulates recent advancements in understanding immunosenescence, with a focus on T cell senescence, and the regulatory mechanisms involving TERT/telomerase. Additionally, it comprehensively discusses strategies aimed at inhibiting immunosenescence by augmenting TERT/telomerase activity.


Assuntos
Senescência Celular , Imunossenescência , Linfócitos T , Telomerase , Telomerase/imunologia , Telomerase/metabolismo , Humanos , Imunossenescência/imunologia , Linfócitos T/imunologia , Senescência Celular/imunologia , Animais , Imunidade Adaptativa
6.
BMC Psychiatry ; 24(1): 661, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39379870

RESUMO

BACKGROUND: As a biological marker for cellular senescence, telomere length (TL) has been linked to a variety of psychiatric disorders and adverse childhood experiences (ACE), though only preliminarily to peripartum depression (PPD). The present study sought to examine the association between TL and PPD, assessing the moderating role of ACE and genetic polymorphic variations related with the telomere machinery. METHODS: Adversity was self-reported, likewise were depressive symptoms evaluated at pregnancy week 17 and 32, as well as six-weeks and six-months postpartum. TL was assessed by use of qPCR in blood samples collected during delivery from females with antenatal depression resolving postpartum, females with depression persisting to postpartum, and healthy controls. Twenty haplotype-tagging Single Nucleotide Polymorphisms in the Telomerase Reverse Transcriptase (TERT) and three in the Telomerase RNA Component (TERC) genes were genotyped. RESULTS: TL was negatively correlated with severity of PPD symptoms at pregnancy week 32 and postpartum week 6. PPD was associated with shorter TL. Lastly, ACE, but not the TERT/TERC genotype, moderated the TL-trajectory association; with increasing ACE, individuals with persistent PPD symptoms had shorter TL, whereas the opposite pattern (longer TL) was observed in the controls. CONCLUSIONS: The findings contribute to further understanding of PPD underpinnings, suggesting a negative relationship with TL.


Assuntos
Experiências Adversas da Infância , Período Periparto , Polimorfismo de Nucleotídeo Único , Telomerase , Humanos , Feminino , Adulto , Telomerase/genética , Período Periparto/genética , Gravidez , Polimorfismo de Nucleotídeo Único/genética , Genótipo , Telômero/genética , RNA/genética , Depressão Pós-Parto/genética , Encurtamento do Telômero/genética , Depressão/genética , Complicações na Gravidez/genética
7.
Sci Rep ; 14(1): 23719, 2024 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-39390090

RESUMO

Telomerase reverse transcriptase promoter (TERTp) mutations are associated with non-radioiodine avidity. However, the role of these mutations in the clinical outcomes of patients with radioiodine-refractory differentiated thyroid cancer (RAIR-DTC) remains unknown. Herein, we aim to analyze gene mutations and clinical manifestations to verify TERTp's role in driving disease progression to RAIR-DTC and clinical outcomes. Next-generation sequencing data and clinical data were obtained from 243 patients with DTC. Of the 25 patients with TERTp mutations, 80% (20/25) had RAIR-DTC. RAIR-DTC was significantly less prevalent in patients with BRAFV600E (9/143, 6.3%) than those with both BRAFV600E and TERTp mutations (14/17, 82.4%). Patients with RAIR-DTC harboring both BRAFV600E and TERTp mutations were more likely to have > 3 distant metastatic sites (85.7%, 12/14) than those with BRAFV600E alone (33.3%, 3/9). Only one patient with both BRAFV600E and TERTp mutations had non-RAIR-DTC. The time from initial radioactive iodine therapy to RAIR-DTC diagnosis was significantly shorter in patients with TERTp mutations than in those without. Patients with BRAFV600E and TERTp mutations progressed faster to RAIR-DTC than those with BRAFV600E alone (p < 0.01). Our findings suggest that molecular testing for TERTp and other mutations like BRAFV600E may inform early diagnosis, prognosis, and treatment strategies before progression to RAIR-DTC.


Assuntos
Mutação , Regiões Promotoras Genéticas , Telomerase , Neoplasias da Glândula Tireoide , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Progressão da Doença , Radioisótopos do Iodo/uso terapêutico , Prognóstico , Proteínas Proto-Oncogênicas B-raf/genética , Telomerase/genética , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/patologia
8.
Endocr Pathol ; 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39363120

RESUMO

De-escalation of thyroid cancer treatment is crucial to prevent overtreatment of indolent disease, but it remains important to identify clinically aggressive cases. TERT promoter mutations are molecular events frequently associated with high-risk thyroid tumors with poor outcomes and may identify cases at risk of dissemination. In various international guidelines, small minimally invasive follicular thyroid carcinoma and oncocytic thyroid carcinoma (miFTC/miOTC) are classified as low-risk lesions and are not recommended adjuvant treatment. Our study aimed to explore the association between size-based risk assessment and TERT promoter mutations. Between 2019 and May 2024, 84 miFTCs/miOTCs diagnosed at our department underwent digital droplet PCR analysis targeting TERT promoter mutational hotspots C228T and C250T in clinical routine. TERT promoter mutations were found in 10 out of 84 cases (11.9%). Mutated cases were pT1 (n = 1), pT2 (n = 3), or pT3 (n = 6). Patients with mutated tumors were older compared to patients with wild-type tumors (median age of 71 years vs. 57 years, p = 0.041). There were no significant differences regarding patient sex, tumor size, Ki-67 labeling index, or the presence of distant metastases. Notably, 30% of mutations displayed variant allele frequencies < 10%, possibly suggesting subclonal events. To conclude, TERT promoter mutations in miFTCs and miOTCs were associated with higher patient age and were often suspected to be subclonal. However, they did not affect clinical outcomes, possibly due to short follow-up. Reflex testing for this genetic alteration in miFTCs and miOTCs could be justified regardless of tumor size, though the clinical benefit remains uncertain.

9.
Physiol Genomics ; 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39374082

RESUMO

Cancer remains a leading cause of death worldwide and although prognosis and survivorship after therapy has improved significantly, current cancer treatments have long-term health consequences. For decades telomerase-mediated telomere maintenance has been an attractive anti-cancer therapeutic target due to its abundance and role in telomere maintenance, pathogenesis and growth in neoplasms. Telomere maintenance-specific cancer therapies, however, are marred by off target side-effects that must be addressed before they reach clinical practice. Regular exercise training is associated with telomerase-mediated telomere maintenance in healthy cells, which is associated with healthy ageing. A single bout of endurance exercise training dynamically, but temporarily, increases TERT mRNA and telomerase activity, as well as several molecules that control genomic stability and telomere length (i.e., shelterin and TERRA). Considering the epidemiological findings and accumulating research highlighting that exercise significantly reduces the risk of many types of cancers and the anti-carcinogenic effects of exercise on tumour growth in vitro, investigating the governing molecular mechanisms of telomerase control in context with exercise and cancer may provide important new insights to explain these findings. Specifically, the molecular mechanisms controlling telomerase in both healthy cells and tumours after exercise could reveal novel therapeutic targets for tumour-specific telomere maintenance and offer important evidence that could refine current physical activity and exercise guidelines for all stages of cancer care.

10.
Diagn Pathol ; 19(1): 133, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39363234

RESUMO

BACKGROUND: Spitz tumors are relatively uncommon melanocytic lesions, typically affecting a relatively younger population but can be encountered at any age. They are characterized by a proliferation of melanocytes with epithelioid and/or spindled cytomorphology features, and interpretation is often challenging. The majority of these tumors are driven by kinase fusions or HRAS mutations. MAP3K8 fusions, although rare, are characteristic genomic events in Spitz tumors, especially in more atypical or malignant lesions. CASE PRESENTATION: Here, we present the case of a 43-year-old woman with a clinically cystic mass in her right groin, histologically characterized as a spindle and epithelioid cell malignant tumor. Immunohistochemistry revealed diffuse expression of S100 protein, tyrosinase and SOX10, patchy weak PRAME, HMB45 and Melan-A reactivity, and negative staining for BRAF V600E. Next-generation sequencing analysis revealed the presence of a MAP3K8::ABLIM1 fusion gene, as well as GRIN2A and TERT promoter mutations. The morphology, immunohistochemistry and molecular analysis confirmed Spitz melanoma with molecular features suggesting a worse prognosis. CONCLUSION: This case introduces a novel fusion partner of MAP3K8 in the context of Spitz melanoma and expands the morphologic and molecular spectrum of Spitz melanoma.


Assuntos
Melanoma , Nevo de Células Epitelioides e Fusiformes , Neoplasias Cutâneas , Adulto , Feminino , Humanos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/análise , Rearranjo Gênico , Imuno-Histoquímica , MAP Quinase Quinase Quinases/genética , MAP Quinase Quinase Quinases/metabolismo , Melanoma/genética , Melanoma/patologia , Melanoma/diagnóstico , Nevo de Células Epitelioides e Fusiformes/genética , Nevo de Células Epitelioides e Fusiformes/patologia , Proteínas Proto-Oncogênicas/genética , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia
11.
BMC Vet Res ; 20(1): 485, 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39448973

RESUMO

BACKGROUND: Biological aging is a complex process influenced by various factors, including reproductive status and castration. This study aimed to evaluate the impact of castration on biological aging in dogs. METHOD: Fifteen male crossbred dogs were randomly divided into a sham-operation control group (n = 5) and a castrated group (n = 10). Blood samples were collected at weeks 0, 4, 8, 12, 16, and 18 post-surgery. Malondialdehyde (MDA as indicator of Lipid peroxidation), C-reactive protein (as an indicator of inflammation), telomere length, mitochondrial DNA (mtDNA) copy number, and the expression of age-related (P16, P21, TBX2) and telomerase-related (TERT) genes were assessed in blood samples. RESULTS: Plasma MDA levels were higher in the control group at weeks 16 and 18, while CRP levels were higher only at week 18. Telomere length and mtDNA copy number were lower in the control group at week 18. Gene expression analysis showed that P16 was lower in the control group at weeks 8 and 12, P21 and TERT were lower at weeks 16 and 18, and TBX2 was lower at weeks 16 and 18. The TBX2/P16 ratio was lower in the control group at weeks 16 and 18 but higher at week 12, while the TBX2/P21 ratio did not differ between groups. CONCLUSION: Castration appears to have a protective effect against biological aging in dogs, as evidenced by lower lipid peroxidation, inflammation, and age-related changes in telomere length, mtDNA copy number, and gene expression.


Assuntos
Envelhecimento , DNA Mitocondrial , Inflamação , Peroxidação de Lipídeos , Telomerase , Animais , Cães , Masculino , Telomerase/genética , Telomerase/metabolismo , Inflamação/veterinária , Inflamação/genética , Inflamação/metabolismo , DNA Mitocondrial/genética , Telômero , Orquiectomia/veterinária , Malondialdeído/sangue , Malondialdeído/metabolismo , Proteína C-Reativa/metabolismo , Proteína C-Reativa/genética , Proteína C-Reativa/análise , Variações do Número de Cópias de DNA
12.
J Fluoresc ; 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39441257

RESUMO

A novel fluorometric method is presented for accurately quantifying peroxiredoxin (Prx) enzyme activity in vitro. The rate-limiting step in the Prx-catalyzed reaction is the dissociation of peroxide. To avoid interference from catalase, we developed an assay using tert-butyl hydroperoxide (t-BOOH) as a substrate for specific Prx activity measurement. The assay involves incubating the enzyme substrates 1,4-dithio-DL-threitol (DTT) and t-BOOH in a suitable buffer at 37 °C for 10 min in a known volume of Prx enzyme. Following incubation, the reagent monobromobimane (mBB) is added to terminate the enzymatic reaction and produce a fluorescent product. Prx activity is subsequently determined by measuring thiol fluorescence, with reaction conditions optimized using a Bland-Altman plot. The efficacy of this novel protocol was rigorously validated by comparing Prx activity measurements from paired samples with those generated by a reference assay. A correlation coefficient of 0.995 was observed between the two methods, demonstrating superior precision and reliability compared to existing methods. The mBB-Prx protocol offers a significant safety advantage by using t-BOOH as a substrate for Prx activity measurement. As catalase does not catalyze t-BOOH dissociation, including sodium azide is unnecessary. Moreover, the method obviates the need for concentrated acids to terminate the Prx enzymatic reaction, as the mBB reagent efficiently inhibits Prx activity. This streamlined approach simplifies the assay and significantly improves its safety and usability, providing users with a reliable and convenient tool. The convenience of this method allows users to focus on their research without worrying about safety or complex procedures.

13.
World J Microbiol Biotechnol ; 40(11): 364, 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39446252

RESUMO

The phenolic antioxidant 2,6-Di-tert-butyl-p-cresol (BHT) has been detected in various environments and is considered a potential threat to aquatic organisms. Algal-bacterial interactions are crucial for maintaining ecosystem balance and elemental cycling, but their response to BHT remains to be investigated. This study analyzed the physiological and biochemical responses of the microalga Isochrysis galbana and the changes of associated bacterial communities under different concentrations of BHT stress. Results showed that the biomass of I. galbana exhibited a decreasing trend with increasing BHT concentrations up to 40 mg/L. The reduction in chlorophyll, carotenoid, and soluble protein content of microalgal cells was also observed under BHT stress. The production of malondialdehyde and the activities of superoxide dismutase, peroxidase, and catalase were further determined. Scanning electron microscopy analysis revealed that BHT caused surface rupture of the algal cells and loss of intracellular nutrients. Proteomic analysis demonstrated the upregulation of photosynthesis and citric acid cycle pathways as a response to BHT stress. Additionally, BHT significantly increased the relative abundance of specific bacteria in the phycosphere, including Marivita, Halomonas, Marinobacter, and Alteromonas. Further experiments confirmed that these bacteria had the ability to utilize BHT as the sole carbon resource for growth, and genes related to the degradation of phenolic compounds were detected through pangenome analysis.


Assuntos
Bactérias , Cresóis , Microalgas , Proteoma , Estresse Fisiológico , Microalgas/metabolismo , Microalgas/genética , Cresóis/metabolismo , Bactérias/genética , Bactérias/metabolismo , Bactérias/classificação , Haptófitas/metabolismo , Haptófitas/genética , Proteômica , Fotossíntese , Antioxidantes/metabolismo , Biomassa , Clorofila/metabolismo
14.
Top Curr Chem (Cham) ; 382(4): 32, 2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39394383

RESUMO

The astounding reactivity of tert-butoxides in transition metal-free coupling reactions is driving the scientific community towards a new era of environmental friendly, as well as cost-effective, transformation strategies. Transition metal-catalyzed coupling reactions generate hazardous wastes and require harsh reaction conditions, mostly at elevated temperature, which increases not only costs but also environmental concerns regarding the methodology. Tert-butoxide-catalyzed/mediated coupling reactions have several advantages and potential applications. They can form carbon-carbon, carbon-heteroatom, and heteroatom-heteroatom bonds under mild reaction conditions. Mechanistic insights into these reactions include both ionic and radical pathways, with the fate of the intermediates depending on the reaction conditions and/or additives used in the reactions. Among all of the known tert-butoxides, potassium tert-butoxide has pronounced applications in transition metal-free coupling reactions as compared to other tert-butoxides, such as sodium and lithium tert-butoxides, because of the higher electropositivity of potassium compared to sodium and lithium. Moreover, potassium tert-butoxide can act as a source of base, nucleophile and single electron donors in various important transformations. In this review, we provide an extensive overview and complete compilation of transition metal-free cross-coupling reactions catalyzed/promoted by tert-butoxides during the past 10 years.


Assuntos
Elementos de Transição , Catálise , Elementos de Transição/química , Butanóis/química , Estrutura Molecular
15.
Food Chem X ; 24: 101806, 2024 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-39296482

RESUMO

Glyphosate and glufosinate are the most widely used herbicides worldwide. We developed a simple and rapid analytical method for detecting glyphosate, glufosinate, and their metabolites (N-acetyl glyphosate: Gly-A, N-acetyl glufosinate: Glu-A, and 3-(hydroxymethylphosphinyl)propanoic acid: MPPA) in soybeans. The method involved extraction with water, trapping in a mini-column containing polymer-based resin with strong anion exchange groups, dehydration with acetonitrile, and solid-phase analytical derivatization at ambient temperature for 1 min using N-(tert-butyldimethylsilyl)-N-methyl trifluoroacetamide (MTBSTFA), followed by Liquid chromatography-tandem mass spectrometry (LC-MS/MS) determination. This method offers a straightforward and rapid analysis, using on-solid phase dehydration and rapid derivatization at an ambient temperature with MTBSTFA, yielding reliable results for glyphosate, glufosinate, and their metabolites. The method was applied to both domestic and imported soybean samples. Glyphosate, glufosinate, and Glu-A were detected in imported feed soybeans and processed soybean meal for feed use, reflecting the current conditions of GM soybean cultivation.

16.
Cureus ; 16(8): e66651, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39258061

RESUMO

Malignant melanoma is a common and aggressive skin cancer with a high incidence of metastases. Diagnosis is usually straightforward, based on a combination of histomorphology and immunohistochemistry. However, metastatic melanoma is notorious for its phenotypic diversity and loss of differentiation markers. Through recent developments in diagnostic immunohistochemistry and molecular pathology, several new markers are identified to be of use in confirming melanoma diagnosis, especially in undifferentiated and dedifferentiated cases. Here we report a challenging case of a 59-year-old male with splenic metastatic melanoma which revealed a loss of four diagnostic melanocytic markers including S100, SOX-10, HMB45, and MART-1, but a gain of SOX-11.

17.
Balkan J Med Genet ; 27(1): 59-63, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39263645

RESUMO

The pathogenic variants in the telomerase reverse transcriptase (TERT) gene have been identified in adults with idiopathic pulmonary fibrosis, while their connection to childhood diffuse lung disease has not yet been described. Within this study, we present a case of a five-month-old, previously healthy infant, with early-onset respiratory failure. The clinical suspicion of diffuse lung disease triggered by cytomegalovirus (CMV) pneumonitis was based on clinical and radiological presentation. Multiorgan involvement was not confirmed. Considering the possible connection between CMV pneumonitis and early-onset respiratory failure, clinical exome sequencing was performed and a novel variant, classified as likely pathogenic in the TERT gene (c.280A>T, p.Lys94Ter) was detected. After segregation analysis yielded negative results, the de novo status of the variant was confirmed. Respiratory support, antiviral and anti-inflammatory therapy offered modest benefits, nevertheless, eighteen months after the initial presentation of disease, an unfavourable outcome occurred. In conclusion, severe viral pneumonia has the potential to induce extremely rare early-onset diffuse lung disease accompanied by chronic respiratory insufficiency. This is linked to pathogenic variants in the TERT gene. Our comprehensive presentation of the patient contributes to valuable insights into the intricate interplay of genetic factors, clinical presentations, and therapeutic outcomes in cases of early-onset respiratory failure.

18.
Artigo em Inglês | MEDLINE | ID: mdl-39269467

RESUMO

Impaired alveolar epithelial regeneration in patients with idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD) is attributed to telomere dysfunction in type II alveolar epithelial cells (A2Cs). Genetic susceptibility, aging, and toxicant exposures, including tobacco smoke (TS), contribute to telomere dysfunction in A2Cs. Here we investigated whether improvement of telomere function plays a role in CSP7-mediated protection of A2Cs against ongoing senescence and apoptosis during bleomycin (BLM)-induced pulmonary fibrosis (PF) as well as alveolar injury caused by chronic TS exposure. We found a significant telomere shortening in A2Cs isolated from IPF and COPD lungs in line with other studies. These cells showed increased p53 in addition to its post-translational modification with induction of activated caspase-3 and ß-galactosidase, suggesting a p53-mediated loss of A2C renewal. Further, we found increased expression of SIAH-1, a p53-inducible E3 ubiquitin ligase known to down-regulate telomere repeats binding factor 2 (TRF2). Consistent with the loss of TRF2 and upregulation of TRF1, telomerase reverse transcriptase (TERT) was downregulated in A2Cs. A2Cs from fibrotic lungs of mice either repeatedly instilled with BLM or isolated from chronic TS exposure-induced lung injury model showed reduced telomere length along with induction of p53, PAI-1, SIAH1 and TRF1 as well as loss of TRF2 and TERT, which were reversed in wild-type mice after treatment with CSP7. Interestingly, PAI-1-/- mice, or those lacking microRNA-34a expression in A2Cs, resisted telomere dysfunction, while uPA-/- mice failed to respond to CSP7 treatment, suggesting p53-microRNA-34a feed-forward induction and p53-uPA pathway contributes to telomere dysfunction.

19.
J Nanobiotechnology ; 22(1): 557, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39267048

RESUMO

An increasing body of evidence suggests that acylphosphatase-2 (ACYP2) polymorphisms are correlated with an increased susceptibility to a range of malignancies. Nevertheless, its potential functions, molecular mechanisms in hepatocellular carcinoma (HCC) and whether it can be act as a therapeutic target remain uninvestigated. Herein, ACYP2 was found to be lowly expressed in HCC and was negatively correlated with tumor size, tumor differentiation, microvascular invasion and the prognosis of HCC patients. Functional investigations revealed that overexpression of ACYP2 inhibited the proliferation and metastasis of HCC cells while promoting apoptosis; knockdown of ACYP2 had the exact opposite effect. Additionally, it was observed that ACYP2 was distributed in both the cytoplasm and nucleus of HCC cells. According to the mechanistic studies, the expression of potassium calcium-activated channel subfamily N member 4 (KCNN4) was negatively regulated by cytoplasmic ACYP2, resulting in the inhibition of K+ outflow and subsequent inactivation of the ERK pathway, which impeded the growth and metastasis of HCC. Furthermore, the activity of telomerase reverse transcriptase (TERT) was inhibited by nuclear ACYP2, leading to the reduction in length of telomeres and consequent reversal of HCC cell immortalization. Additionally, a novel targeted nanotherapy strategy was developed wherein the pcDNA-ACYP2 vector was encapsulated within polyetherimide nanoparticles (PEI/NPs), which were subsequently coated with HCC cell membranes (namely pcDNA/PEI/NPs@M). Safety and targeting characteristics abound for these nanocomposites, in both subcutaneous graft tumor models and orthotopic mouse models, they inhibited the progression of HCC by impeding TERT activity and the KCNN4/ERK pathway. In conclusion, our research identifies novel molecular mechanisms involving cytoplasmic and nuclear ACYP2 that inhibit the progression of HCC. Moreover, pcDNA/PEI/NPs@M represents a targeted therapeutic strategy for HCC that holds great promising.


Assuntos
Carcinoma Hepatocelular , Proliferação de Células , Canais de Potássio Ativados por Cálcio de Condutância Intermediária , Neoplasias Hepáticas , Sistema de Sinalização das MAP Quinases , Telomerase , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Telomerase/metabolismo , Telomerase/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Camundongos , Masculino , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/antagonistas & inibidores , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos Nus , Apoptose/efeitos dos fármacos , Feminino , Progressão da Doença , Camundongos Endogâmicos BALB C , Nanopartículas/química , Pessoa de Meia-Idade
20.
Foods ; 13(18)2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39335924

RESUMO

Tert-butylhydroquinone (TBHQ) is a phenolic substance that is commonly employed to prevent food oxidation. Excessive or improper utilization of this antioxidant can not only impact food quality but may also pose potential risks to human health. In this study, an ultrasensitive, stable, and easily operable ratiometric electrochemical sensor was successfully fabricated by combining the tubular (3,4-ethylenedioxythiophene) (T-PEDOT) with single-wall carbon nanohorns (SWCNHs) for the detection of TBHQ antioxidants in food. The SWCNHs/T-PEDOT nanocomposite fabricated through ultrasound-assisted and template approaches was employed as the modified substrate for the electrode interface. The synergistic effect of SWCNHs and T-PEDOT, which possess excellent electrical conductivity and catalytic properties, enabled the modified electrode to showcase remarkable electrocatalytic performance towards TBHQ, with the redox signal of methylene blue serving as an internal reference. Under optimized conditions, the SWCNHs/T-PEDOT-modified electrode demonstrated good linearity within the TBHQ concentration range of 0.01-200.0 µg mL-1, featuring a low limit of detection (LOD) of 0.005 µg mL-1. The proposed ratiometric electrochemical sensor displayed favorable reproducibility, stability, and anti-interference capacity, thereby offering a promising strategy for monitoring the levels of TBHQ in oil-rich food products.

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