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1.
Nature ; 578(7795): 437-443, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32025032

RESUMO

LGR5 marks resident adult epithelial stem cells at the gland base in the mouse pyloric stomach1, but the identity of the equivalent human stem cell population remains unknown owing to a lack of surface markers that facilitate its prospective isolation and validation. In mouse models of intestinal cancer, LGR5+ intestinal stem cells are major sources of cancer following hyperactivation of the WNT pathway2. However, the contribution of pyloric LGR5+ stem cells to gastric cancer following dysregulation of the WNT pathway-a frequent event in gastric cancer in humans3-is unknown. Here we use comparative profiling of LGR5+ stem cell populations along the mouse gastrointestinal tract to identify, and then functionally validate, the membrane protein AQP5 as a marker that enriches for mouse and human adult pyloric stem cells. We show that stem cells within the AQP5+ compartment are a source of WNT-driven, invasive gastric cancer in vivo, using newly generated Aqp5-creERT2 mouse models. Additionally, tumour-resident AQP5+ cells can selectively initiate organoid growth in vitro, which indicates that this population contains potential cancer stem cells. In humans, AQP5 is frequently expressed in primary intestinal and diffuse subtypes of gastric cancer (and in metastases of these subtypes), and often displays altered cellular localization compared with healthy tissue. These newly identified markers and mouse models will be an invaluable resource for deciphering the early formation of gastric cancer, and for isolating and characterizing human-stomach stem cells as a prerequisite for harnessing the regenerative-medicine potential of these cells in the clinic.


Assuntos
Aquaporina 5/metabolismo , Carcinogênese/patologia , Células-Tronco Neoplásicas/patologia , Neoplasias Gástricas/patologia , Estômago/patologia , Animais , Biomarcadores/metabolismo , Humanos , Camundongos , Células-Tronco Neoplásicas/metabolismo , Piloro/patologia , Receptores Acoplados a Proteínas G/metabolismo , Via de Sinalização Wnt
2.
Hum Mol Genet ; 32(2): 177-191, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-35925868

RESUMO

Mutations in LMNA, the gene encoding A-type lamins, cause laminopathies-diseases of striated muscle and other tissues. The aetiology of laminopathies has been attributed to perturbation of chromatin organization or structural weakening of the nuclear envelope (NE) such that the nucleus becomes more prone to mechanical damage. The latter model requires a conduit for force transmission to the nucleus. NE-associated Linker of Nucleoskeleton and Cytoskeleton (LINC) complexes are one such pathway. Using clustered regularly interspaced short palindromic repeats to disrupt the Nesprin-1 KASH (Klarsicht, ANC-1, Syne Homology) domain, we identified this LINC complex protein as the predominant NE anchor for microtubule cytoskeleton components, including nucleation activities and motor complexes, in mouse cardiomyocytes. Loss of Nesprin-1 LINC complexes resulted in loss of microtubule cytoskeleton proteins at the nucleus and changes in nuclear morphology and positioning in striated muscle cells, but with no overt physiological defects. Disrupting the KASH domain of Nesprin-1 suppresses Lmna-linked cardiac pathology, likely by reducing microtubule cytoskeleton activities at the nucleus. Nesprin-1 LINC complexes thus represent a potential therapeutic target for striated muscle laminopathies.


Assuntos
Laminopatias , Músculo Estriado , Animais , Camundongos , Proteínas dos Microtúbulos/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Membrana/genética , Citoesqueleto/genética , Citoesqueleto/metabolismo , Matriz Nuclear/genética , Microtúbulos/metabolismo , Membrana Nuclear/genética , Membrana Nuclear/metabolismo , Proteínas de Filamentos Intermediários/metabolismo , Músculo Estriado/metabolismo , Laminopatias/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-38724446

RESUMO

BACKGROUND: Preemptive kidney transplantation has better outcomes when compared to transplantation after dialysis. We aimed to examine trends in preemptive kidney transplantation between 2000 and 2019 in Europe and to provide an overview of associated policies, barriers and initiatives. METHODS: Adult patients from 12 European countries who received a preemptive kidney transplant were included. The representatives of the registries providing these data were questioned on the policies, barriers and initiatives around preemptive kidney transplantation. RESULTS: Between 2000 and 2019, 20 251 adults underwent preemptive kidney transplantation (11 169 from living donors, 8937 from deceased donors). The proportion of first kidney transplantations that were preemptive more than doubled from 7% in 2000 to 18% in 2019, reflecting a similar relative increase for living donor kidney recipients (from 21% to 43%) and deceased donor kidney recipients (from 4% to 11%). Large international differences were found. The increase in preemptive kidney transplantation was observed across all age, sex and primary renal disease groups. Countries had similar criteria for preemptive waitlisting. Barriers mentioned included donor shortage, late referral to the transplant center and long donor or recipient work-up. Suggested initiatives included raising awareness on the possibility of preemptive kidney transplantation, earlier start and shorter work-up time for recipient and living donor. CONCLUSIONS: Over the last two decades the proportion of patients receiving a first kidney transplant preemptively has more than doubled, reflecting a similar relative increase for living and deceased donor kidney recipients.

4.
Diabetes Obes Metab ; 26(8): 3328-3338, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38779875

RESUMO

AIM: Patients with metabolic dysfunction-associated steatotic liver disease (MASLD) are at increased risk of incident cardiovascular disease. However, the clinical characteristics and prognostic importance of MASLD in patients presenting with acute myocardial infarction (AMI) have yet to be examined. METHODS: This study compared the characteristics and outcomes of patients with and without MASLD presenting with AMI at a tertiary centre in Singapore. MASLD was defined as hepatic steatosis, with at least one of five metabolic criteria. Hepatic steatosis was determined using the Hepatic Steatosis Index. Propensity score matching was performed to adjust for age and sex. The Kaplan-Meier curve was constructed for long-term all-cause mortality. Cox regression analysis was used to investigate independent predictors of long-term all-cause mortality. RESULTS: In this study of 4446 patients with AMI, 2223 patients with MASLD were matched with patients without MASLD using propensity scores. The mean follow-up duration was 3.4 ± 2.4 years. The MASLD group had higher rates of obesity, diabetes and chronic kidney disease than their counterparts. Patients with MASLD had early excess all-cause mortality (6.8% vs. 3.6%, p < .001) at 30 days, with unfavourable mortality rates sustained in the long-term (18.3% vs. 14.5%, p = .001) compared with those without MASLD. After adjustment, MASLD remained independently associated with higher long-term all-cause mortality (hazard ratio 1.330, 95% confidence interval 1.106-1.598, p = .002). CONCLUSION: MASLD embodies a higher burden of metabolic dysfunction and is an independent predictor of long-term mortality in the AMI population. Its early identification may be beneficial for risk stratification and provide therapeutic targets for secondary preventive strategies in AMI.


Assuntos
Infarto do Miocárdio , Pontuação de Propensão , Humanos , Masculino , Feminino , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/epidemiologia , Pessoa de Meia-Idade , Prognóstico , Idoso , Singapura/epidemiologia , Fígado Gorduroso/complicações , Fígado Gorduroso/mortalidade , Fatores de Risco , Estudos Retrospectivos
5.
Blood ; 138(6): 452-463, 2021 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-33728448

RESUMO

Current prognostic scoring systems based on clinicopathologic variables are inadequate in predicting the survival and treatment response of extranodal natural killer/T-cell lymphoma (ENKTL) patients undergoing nonanthracyline-based treatment. We aimed to construct a classifier based on single-nucleotide polymorphisms (SNPs) for improving predictive accuracy and guiding clinical decision making. Data from 722 patients with ENKTL from international centers were analyzed. A 7-SNP-based classifier was constructed using LASSO Cox regression in the training cohort (n = 336) and further validated in the internal testing cohort (n = 144) and in 2 external validation cohorts (n = 142 and n = 100). The 7-SNP-based classifier showed good prognostic predictive efficacy in the training cohort and the 3 validation cohorts. Patients with high- and low-risk scores calculated by the classifier exhibited significantly different progression-free survival (PFS) and overall survival (OS) (all P < .001). The 7-SNP-based classifier was further proved to be an independent prognostic factor by multivariate analysis, and its predictive accuracy was significantly better than clinicopathological risk variables. Application of the 7-SNP-based classifier was not affected by sample types. Notably, chemotherapy combined with radiotherapy significantly improved PFS and OS vs radiotherapy alone in high-risk Ann Arbor stage I patients, whereas there was no statistical difference between the 2 therapeutic modalities among low-risk patients. A nomogram was constructed comprising the classifier and clinicopathological variables; it showed remarkably better predictive accuracy than either variable alone. The 7-SNP-based classifier is a complement to existing risk-stratification systems in ENKTL, which could have significant implications for clinical decision making for patients with ENKTL.


Assuntos
Linfoma Extranodal de Células T-NK , Polimorfismo de Nucleotídeo Único , Intervalo Livre de Doença , Feminino , Humanos , Linfoma Extranodal de Células T-NK/genética , Linfoma Extranodal de Células T-NK/mortalidade , Linfoma Extranodal de Células T-NK/radioterapia , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida
6.
BMC Nephrol ; 24(1): 144, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37226118

RESUMO

BACKGROUND: Incidence of acute kidney injury (AKI) is known to peak in winter months. This is likely influenced by seasonality of commonly associated acute illnesses. We set out to assess seasonal mortality trends for patients who develop AKI across the English National Health Service (NHS) and to better understand associations with patient 'case-mix'. METHODS: The study cohort included all hospitalised adult patients in England who triggered a biochemical AKI alert in 2017. We modelled the impact of season on 30-day mortality using multivariable logistic regression; adjusting for age, sex, ethnicity, index of multiple deprivation (IMD), primary diagnosis, comorbidity (RCCI), elective/emergency admission, peak AKI stage and community/hospital acquired AKI. Seasonal odds ratios for AKI mortality were then calculated and compared across individual NHS hospital trusts. RESULTS: The crude 30-day mortality for hospitalised AKI patients was 33% higher in winter compared to summer. Case-mix adjustment for a wide range of clinical and demographic factors did not fully explain excess winter mortality. The adjusted odds ratio of patients dying in winter vs. summer was 1.25 (1.22-1.29), this was higher than for Autumn and Spring vs. Summer, 1.09 (1.06-1.12) and 1.07 (1.04-1.11) respectively and varied across different NHS trusts (9 out of 90 centres outliers). CONCLUSION: We have demonstrated an excess winter mortality risk for hospitalised patients with AKI across the English NHS, which could not be fully explained by seasonal variation in patient case-mix. Whilst the explanation for worse winter outcomes is not clear, unaccounted differences including 'winter-pressures' merit further investigation.


Assuntos
Injúria Renal Aguda , Medicina Estatal , Adulto , Humanos , Estações do Ano , Inglaterra/epidemiologia , Clima
7.
Development ; 146(19)2019 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-30846446

RESUMO

Global epigenetic reprogramming is vital to purge germ cell-specific epigenetic features to establish the totipotent state of the embryo. This process transpires to be carefully regulated and is not an undirected, radical erasure of parental epigenomes. The TRIM28 complex has been shown to be crucial in embryonic epigenetic reprogramming by regionally opposing DNA demethylation to preserve vital parental information to be inherited from germline to soma. Yet the DNA-binding factors guiding this complex to specific targets are largely unknown. Here, we uncover and characterize a novel, maternally expressed, TRIM28-interacting KRAB zinc-finger protein: ZFP708. It recruits the repressive TRIM28 complex to RMER19B retrotransposons to evoke regional heterochromatin formation. ZFP708 binding to these hitherto unknown TRIM28 targets is DNA methylation and H3K9me3 independent. ZFP708 mutant mice are viable and fertile, yet embryos fail to inherit and maintain DNA methylation at ZFP708 target sites. This can result in activation of RMER19B-adjacent genes, while ectopic expression of ZFP708 results in transcriptional repression. Finally, we describe the evolutionary conservation of ZFP708 in mice and rats, which is linked to the conserved presence of the targeted RMER19B retrotransposons in these species.


Assuntos
Repressão Epigenética , Proteínas Repressoras/metabolismo , Retroelementos/genética , Dedos de Zinco , Animais , Sequência de Bases , Sítios de Ligação/genética , Blastocisto/metabolismo , Metilação de DNA/genética , Embrião de Mamíferos/metabolismo , Evolução Molecular , Camundongos , Camundongos Knockout , Células-Tronco Embrionárias Murinas/metabolismo , Ligação Proteica/genética , Ratos , Transcrição Gênica , Proteína 28 com Motivo Tripartido/metabolismo
8.
Am J Hematol ; 97(9): 1159-1169, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35726449

RESUMO

With lowering costs of sequencing and genetic profiling techniques, genetic drivers can now be detected readily in tumors but current prognostic models for Natural-killer/T cell lymphoma (NKTCL) have yet to fully leverage on them for prognosticating patients. Here, we used next-generation sequencing to sequence 260 NKTCL tumors, and trained a genomic prognostic model (GPM) with the genomic mutations and survival data from this retrospective cohort of patients using LASSO Cox regression. The GPM is defined by the mutational status of 13 prognostic genes and is weakly correlated with the risk-features in International Prognostic Index (IPI), Prognostic Index for Natural-Killer cell lymphoma (PINK), and PINK-Epstein-Barr virus (PINK-E). Cox-proportional hazard multivariate regression also showed that the new GPM is independent and significant for both progression-free survival (PFS, HR: 3.73, 95% CI 2.07-6.73; p < .001) and overall survival (OS, HR: 5.23, 95% CI 2.57-10.65; p = .001) with known risk-features of these indices. When we assign an additional risk-score to samples, which are mutant for the GPM, the Harrell's C-indices of GPM-augmented IPI, PINK, and PINK-E improved significantly (p < .001, χ2 test) for both PFS and OS. Thus, we report on how genomic mutational information could steer toward better prognostication of NKTCL patients.


Assuntos
Infecções por Vírus Epstein-Barr , Linfoma Extranodal de Células T-NK , Intervalo Livre de Doença , Genômica , Herpesvirus Humano 4 , Humanos , Prognóstico , Estudos Retrospectivos
9.
Med Res Rev ; 41(6): 3118-3155, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33973253

RESUMO

Over the past decade, significant attention has been given to repurposing Food and Drug Administration approved drugs to treat age-related diseases. In contrast, less consideration has been given to natural bioactive compounds. Consequently, there have been limited attempts to translate these compounds. Autophagy is a fundamental biological pathway linked to aging, and numerous strategies to enhance autophagy have been shown to extend lifespan. Interestingly, there are a number of natural products that are reported to modulate autophagy, and here we describe a number of them that activate autophagy through diverse molecular and cellular mechanisms. Among these, Urolithin A, Spermidine, Resveratrol, Fatty Acids and Phospholipids, Trehalose and Lithium are featured in detail. Finally, we outline possible strategies to optimise and increase the translatability of natural products, with the overall aim of delaying the ageing process and improving human healthspan.


Assuntos
Produtos Biológicos , Senoterapia , Envelhecimento , Autofagia , Produtos Biológicos/farmacologia , Humanos , Longevidade
10.
Eur Radiol ; 31(7): 5050-5058, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33409777

RESUMO

OBJECTIVES: The study aimed to compare the ability of morphological and texture features derived from contrast-enhanced CT in histological subtyping of epithelial ovarian carcinoma (EOC). METHODS: Consecutive 205 patients with newly diagnosed EOC who underwent contrast-enhanced CT were included and dichotomised into high-grade serous carcinoma (HGSC) and non-HGSC. Clinical information including age and cancer antigen 125 (CA-125) was documented. The pre-treatment images were analysed using commercial software, TexRAD, by two independent radiologists. Eight qualitative CT morphological features were evaluated, and 36 CT texture features at 6 spatial scale factors (SSFs) were extracted per patient. Features' reduction was based on kappa score, intra-class correlation coefficient (ICC), univariate ROC analysis and Pearson's correlation test. Texture features with ICC ≥ 0.8 were compared by histological subtypes. Patients were randomly divided into training and testing sets by 8:2. Two random forest classifiers were determined and compared: model 1 incorporating selected morphological and clinical features and model 2 incorporating selected texture and clinical features. RESULTS: HGSC showed specifically higher texture features than non-HGSC (p < 0.05). Both models performed highly in predicting histological subtypes of EOC (model 1: AUC 0.891 and model 2: AUC 0.937), and no statistical significance was found between the two models (p = 0.464). CONCLUSION: CT texture analysis provides objective and quantitative metrics on tumour characteristics with HGSC demonstrating specifically high texture features. The model incorporating texture analysis could classify histology subtypes of EOC with high accuracy and performed as well as morphological features. KEY POINTS: • A number of CT morphological and texture features showed good inter- and intra-observer agreements. • High-grade serous ovarian carcinoma showed specifically higher CT texture features than non-high-grade serous ovarian carcinoma. • CT texture analysis could differentiate histological subtypes of epithelial ovarian carcinoma with high accuracy.


Assuntos
Neoplasias Ovarianas , Carcinoma Epitelial do Ovário/diagnóstico por imagem , Feminino , Humanos , Neoplasias Ovarianas/diagnóstico por imagem , Curva ROC , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
11.
Pharmacoepidemiol Drug Saf ; 30(12): 1687-1695, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34418198

RESUMO

PURPOSE: A laboratory-based acute kidney injury (AKI) electronic-alert (e-alert) system, with e-alerts sent to the UK Renal Registry (UKRR) and collated in a master patient index (MPI), has recently been implemented in England. The aim of this study was to determine the degree of correspondence between the UKRR-MPI and AKI International Classification Disease-10 (ICD-10) N17 coding in Hospital Episode Statistics (HES) and whether hospital N17 coding correlated with 30-day mortality and emergency re-admission after AKI. METHODS: AKI e-alerts in people aged ≥18 years, collated in the UKRR-MPI during 2017, were linked to HES data to identify a hospitalised AKI population. Multivariable logistic regression was used to analyse associations between absence/presence of N17 codes and clinicodemographic features. Correlation of the percentage coded with N17 and 30-day mortality and emergency re-admission after AKI were calculated at hospital level. RESULTS: In 2017, there were 301 540 adult episodes of hospitalised AKI in England. AKI severity was positively associated with coding in HES, with a high degree of inter-hospital variability-AKI stage 1 mean of 48.2% [SD 14.0], versus AKI stage 3 mean of 83.3% [SD 7.3]. N17 coding in HES depended on demographic features, especially age (18-29 years vs. ≥85 years OR 0.22, 95% CI 0.21-0.23), as well as sex and ethnicity. There was no evidence of association between the proportion of episodes coded for AKI with short-term AKI outcomes. CONCLUSION: Coding of AKI in HES is influenced by many factors that result in an underestimation of AKI. Using e-alerts to triangulate the true incidence of AKI could provide a better understanding of the factors that affect hospital coding, potentially leading to improved coding, patient care and pharmacoepidemiologic research.


Assuntos
Injúria Renal Aguda , Registros Eletrônicos de Saúde , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/epidemiologia , Adolescente , Adulto , Eletrônica , Hospitais , Humanos , Laboratórios , Fatores de Risco , Adulto Jovem
12.
Br J Haematol ; 189(4): 731-744, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32004387

RESUMO

Peripheral T-cell lymphomas (PTCL) and natural killer (NK)/T-cell lymphomas (NKTCL) are a heterogeneous group of aggressive malignancies with dismal outcomes and limited treatment options. While the phosphatidylinositol 3-kinase (PIK3) pathway has been shown to be highly activated in many B-cell lymphomas, its therapeutic relevance in PTCL and NKTCL remains unclear. The aim of this study is to investigate the expression of PIK3 and phosphatase and tensin homolog (PTEN) in these subtypes of lymphoma and to identify potential therapeutic targets for clinical testing. Therefore, the expression of PIK3α, PIK3ß, PIK3γ, PIK3δ and PTEN was analyzed in 88 cases of PTCL and NKTCL samples by immunohistochemistry. All PTCL and NKTCL samples demonstrated high expression of PIK3 isoforms. In particular, high PIK3α expression was significantly associated with poor survival, even after adjustment for age, International Prognostic Index (IPI) score and anthracycline-based chemotherapy in first line. Notably, copanlisib, a pan-class I inhibitor with predominant activities towards PIK3α and PIK3δ isoforms, effectively inhibited phosphorylation of AKT, 4E-BP-1 and STAT3, causing G0 /G1 cell cycle arrest and resulting in suppression of tumour cell growth in vitro and in vivo. This study provides evidence that targeting the PIK3 pathway, particularly simultaneous inhibition of PIK3α and δ, could be a promising approach for the treatment of PTCL and NKTCL.


Assuntos
Linfoma de Células T Periférico/tratamento farmacológico , Células T Matadoras Naturais/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Proliferação de Células , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Blood ; 132(11): 1146-1158, 2018 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-30054295

RESUMO

Mature T-cell lymphomas, including peripheral T-cell lymphoma (PTCL) and extranodal NK/T-cell lymphoma (NKTL), represent a heterogeneous group of non-Hodgkin lymphomas with dismal outcomes and limited treatment options. To determine the extent of involvement of the JAK/STAT pathway in this malignancy, we performed targeted capture sequencing of 188 genes in this pathway in 171 PTCL and NKTL cases. A total of 272 nonsynonymous somatic mutations in 101 genes were identified in 73% of the samples, including 258 single-nucleotide variants and 14 insertions or deletions. Recurrent mutations were most frequently located in STAT3 and TP53 (15%), followed by JAK3 and JAK1 (6%) and SOCS1 (4%). A high prevalence of STAT3 mutation (21%) was observed specifically in NKTL. Novel STAT3 mutations (p.D427H, E616G, p.E616K, and p.E696K) were shown to increase STAT3 phosphorylation and transcriptional activity of STAT3 in the absence of cytokine, in which p.E616K induced programmed cell death-ligand 1 (PD-L1) expression by robust binding of activated STAT3 to the PD-L1 gene promoter. Consistent with these findings, PD-L1 was overexpressed in NKTL cell lines harboring hotspot STAT3 mutations, and similar findings were observed by the overexpression of p.E616K and p.E616G in the STAT3 wild-type NKTL cell line. Conversely, STAT3 silencing and inhibition decreased PD-L1 expression in STAT3 mutant NKTL cell lines. In NKTL tumors, STAT3 activation correlated significantly with PD-L1 expression. We demonstrated that STAT3 activation confers high PD-L1 expression, which may promote tumor immune evasion. The combination of PD-1/PD-L1 antibodies and STAT3 inhibitors might be a promising therapeutic approach for NKTL, and possibly PTCL.


Assuntos
Antígeno B7-H1/biossíntese , Regulação Neoplásica da Expressão Gênica , Mutação de Sentido Incorreto , Proteínas de Neoplasias/biossíntese , Fator de Transcrição STAT3/biossíntese , Transdução de Sinais , Substituição de Aminoácidos , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/genética , Linhagem Celular Tumoral , Humanos , Linfoma Extranodal de Células T-NK , Proteínas de Neoplasias/genética , Fator de Transcrição STAT3/genética
14.
Exp Cell Res ; 382(1): 111433, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31100306

RESUMO

Autophagy is an evolutionary conserved, self-eating process that targets cellular constituents for lysosomal degradation. Transcription factor EB (TFEB) is a master regulator of autophagy by inducing the expression of genes involved in autophagic and lysosomal degradation. In breast cancer, ligand-activated progesterone receptor has been reported to influence cancer development by manipulating the autophagy pathway. However, understanding of the mechanism that underlies this autophagic response remains limited. Herein, we report that prolonged treatment with progestin R5020 upregulates autophagy in MCF-7 human breast cancer cells via a novel interplay between progesterone receptor B (PRB) and TFEB. R5020 upregulates TFEB gene expression and protein levels in a PRB-dependent manner. Additionally, R5020 enhances the co-recruitment of PRB and TFEB to each other to facilitate TFEB nuclear localization. Once in the nucleus, TFEB induces the expression of autophagy and lysosomal genes to potentiate autophagy. Together, our findings highlight a novel functional connection between ligand-activated PRB and TFEB to modulate autophagy in MCF-7 breast cancer cells. As breast cancer development is controlled by autophagy, the progestin-PRB-TFEB transduction pathway warrants future attention as a potential therapeutic target in cancer therapy.


Assuntos
Adenocarcinoma/genética , Autofagia/fisiologia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/fisiologia , Neoplasias da Mama/genética , Proteínas de Neoplasias/fisiologia , Receptores de Progesterona/fisiologia , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Autofagossomos/metabolismo , Autofagia/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/biossíntese , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Lisossomos/metabolismo , Células MCF-7 , Proteínas Associadas aos Microtúbulos/biossíntese , Proteínas Associadas aos Microtúbulos/genética , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Promegestona/farmacologia , Mapeamento de Interação de Proteínas , Transporte Proteico/efeitos dos fármacos , Proteínas Recombinantes/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ativação Transcricional
15.
Transfus Med ; 30(6): 456-466, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33103306

RESUMO

OBJECTIVES: To establish, in an unselected population of London haemoglobinopathy patients, transfusion requirements, blood antigens/alloantibodies, transfusion modalities, burden of transfusion reactions and donor exposure. BACKGROUND: Haemoglobinopathy patients are among the most highly transfused patient populations, and the overall population and number of patients on long-term transfusion programmes are increasing. To provide a safe and efficacious transfusion service for patients, it is important to understand current practice, morbidity associated with transfusion, efficacy of different transfusion modalities and geno-/phenotype requirements. METHODS: Data on 4451 transfusion episodes in 760 patients from 12 London hospitals were collected retrospectively over a 6-month period in 2011. RESULTS: Alloimmunisation prevalence was 17% for sickle cell disease (SCD) and 22% for thalassaemia, most commonly anti-Rh/Kell/Kpa /Cw . Rh phenotypes differed between SCD (Ro r 59.8%/R1 r 15.9%/R2 r 15.6%) and thalassaemia (R1 R1 29.6%/R1 r 28.4%/R1 R2 15.4%). Recording of pheno-/genotypes fell below recommendations. A 2-weekly manual exchange and 3-weekly automated exchange came closest to achieving presumptive targets. In adults with thalassaemia, the mean blood requirement was 36 units per year; for SCD, erythrocytapheresis was carried out every 7 weeks with 66 units; for manual exchange, it was 38 units every 4 weeks; and for simple transfusion, it was 30 units p.a. every 4 weeks. CONCLUSION: Transfusion modality choice was influenced by the resources available-children mostly received simple transfusions, and adults received erythrocytapheresis; the relationships between frequency of exchanges/transfusion modality/target HbA% were not simple, possibly reflecting the difference in recipient erythropoiesis and consequent transfusion modality selection bias; adherence to existing and current guidelines regarding geno-/phenotyping was limited; and alloimmunisation had a low incidence and high prevalence in both disorders.


Assuntos
Anemia Falciforme , Citaferese , Transfusão Total , Talassemia , Adolescente , Adulto , Anemia Falciforme/sangue , Anemia Falciforme/epidemiologia , Anemia Falciforme/terapia , Criança , Feminino , Humanos , Londres/epidemiologia , Masculino , Prevalência , Estudos Retrospectivos , Talassemia/sangue , Talassemia/epidemiologia , Talassemia/terapia
16.
BMC Cancer ; 19(1): 953, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31615473

RESUMO

BACKGROUND: Gestational trophoblastic disease (GTD) is a heterogeneous group of diseases developed from trophoblasts. ASPP (Ankyrin-repeat, SH3-domain and proline-rich region containing protein) family proteins, ASPP1 and ASPP2, have been reported to be dysregulated in GTD. They modulate p53 activities and are responsible for multiple cellular processes. Nevertheless, the functional role of the ASPP family inhibitory member, iASPP, is not well characterized in GTD. METHODS: To study the functional role of iASPP in GTD, trophoblastic tissues from normal placentas, hydatidiform mole (HM) and choriocarcinoma were used for immunohistochemistry, whereas siRNAs were used to manipulate iASPP expression in choriocarcinoma cell lines and study the subsequent molecular changes. RESULTS: We demonstrated that iASPP was overexpressed in both HM and choriocarcinoma when compared to normal placenta. Progressive increase in iASPP expression from HM to choriocarcinoma suggests that iASPP may be related to the development of trophoblastic malignancy. High iASPP expression in HM was also significantly associated with a high expression of autophagy-related protein LC3. Interestingly, iASPP silencing retarded the growth of choriocarcinoma through senescence instead of induction of apoptosis. LC3 expression decreased once iASPP was knocked down, suggesting a downregulation on autophagy. This may be due to iASPP downregulation rendered decrease in Atg5 expression and concomitantly hindered autophagy in choriocarcinoma cells. Autophagy inhibition per se had no effect on the growth of choriocarcinoma cells but increased the susceptibility of choriocarcinoma cells to oxidative stress, implying a protective role of iASPP against oxidative stress through autophagy in choriocarcinoma. CONCLUSIONS: iASPP regulates growth and the cellular responses towards oxidative stress in choriocarcinoma cells. Its overexpression is advantageous to the pathogenesis of GTD. (266 words).


Assuntos
Autofagia , Coriocarcinoma/metabolismo , Mola Hidatiforme/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Estresse Oxidativo , Proteínas Repressoras/metabolismo , Adolescente , Adulto , Proteína 5 Relacionada à Autofagia/metabolismo , Linhagem Celular Tumoral , Coriocarcinoma/patologia , Feminino , Seguimentos , Técnicas de Silenciamento de Genes , Humanos , Mola Hidatiforme/patologia , Peptídeos e Proteínas de Sinalização Intracelular/classificação , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Pessoa de Meia-Idade , Placenta/citologia , Placenta/metabolismo , Gravidez , Proteínas Repressoras/classificação , Proteínas Repressoras/genética , Transfecção , Proteína Supressora de Tumor p53/metabolismo , Adulto Jovem
17.
Int J Cancer ; 143(6): 1456-1469, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-29663364

RESUMO

Ovarian clear cell carcinoma (OCCC) is a type of epithelial ovarian cancer that is strongly associated with endometriosis, resistance against conventional chemotherapy and thus poorer prognosis. The expression of inhibitory member of the ASPP family proteins (iASPP) and Polo-like kinase (PLK)1 were significantly higher in OCCC compared to benign cystadenomas and endometriosis. Both protein expressions were found to correlate with chemoresistance in patients with OCCC while high iASPP expression alone was significantly associated with a poor patient survival. The growth of OCCC cell lines, OVTOKO and KK, were inhibited after iASPP silencing. Such effect was related to senescence triggering as evidenced by increased SA-ß-Gal staining and p21WAF1/Cip1 expression. Moreover, knockdown of iASPP induced PLK1 downregulation, whereas either genes' silencing sensitized the cells in response to cisplatin treatment. More prominent apoptosis was induced by cisplatin in OCCC cells after the knockdown of either iASPP or PLK1 as evidenced by the formation of more cleaved caspase 3. Heightened chemosensitivity to cisplatin after iASPP knockdown was further demonstrated in in vivo xenograft model. Additionally, both iASPP and PLK1 were shown to regulate autophagic flux as the induction of LC3B-II and LC3 puncta were much less in OCCC cells with either knockdown. Importantly, inhibition of autophagy also enhanced chemosensitivity to cisplatin in OCCC cells. These findings strongly imply that iASPP and PLK1 affect the chemoresistance of OCCC via the regulation of autophagy and apoptosis. Both iASPP and PLK1 can be potential therapeutic targets for treating OCCC in combination with conventional chemotherapy.


Assuntos
Adenocarcinoma de Células Claras/patologia , Autofagia , Proteínas de Ciclo Celular/metabolismo , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Ovarianas/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Repressoras/metabolismo , Adenocarcinoma de Células Claras/tratamento farmacológico , Adenocarcinoma de Células Claras/metabolismo , Animais , Antineoplásicos/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proteínas de Ciclo Celular/genética , Proliferação de Células , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Prognóstico , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , Transdução de Sinais , Taxa de Sobrevida , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Quinase 1 Polo-Like
18.
Alcohol Clin Exp Res ; 41(1): 197-206, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28029173

RESUMO

BACKGROUND: Alcohol and nicotine dependence frequently co-occur, and quitting smoking might enhance long-term alcohol abstinence. Topiramate appears to help non-alcohol-dependent individuals quit smoking, and our pilot work suggested efficacy only in men. It also prevents relapse to alcohol in recently detoxified alcoholics. We evaluated topiramate in abstinent alcohol-dependent men to assess whether this medication (i) promotes smoking cessation and (ii) prevents alcohol and other drug relapse in the context of smoking cessation treatment. METHODS: One hundred and twenty-nine alcohol-abstinent (mean ~6 months) alcohol-dependent male smokers (80% with other substance use disorders) participated in this 12-week randomized, double blind, parallel group comparison of topiramate (up to 200 mg/d) and placebo with a 24-week nontreatment follow-up period. The study was carried out sequentially at 2 academic centers in the Midwest and Southern California between March 23, 2009 and November 20, 2014. All participants received manual-guided smoking cessation counseling combined with medication-focused compliance enhancement therapy. Randomization was block designed by the research pharmacist in a 1:1 ratio. Participants, investigators, and research personnel were masked to treatment assignment. The primary smoking end point was biochemically confirmed 4-week continuous abstinence from smoking during weeks 9 to 12, while the secondary end point was relapse to any drinking or drug use during the entire 36-week evaluation period. Logistic regression was used to determine the effects of topiramate on quitting smoking and alcohol relapse, controlling for relevant covariates. The trial is registered at ClinicalTrials.gov (number NCT00802412) and is now closed. RESULTS: Only a small proportion (7.9%) of topiramate-treated participants were able to quit smoking, and this cessation rate was similar to placebo (10.6%; odds ratio = 1.60; 95% confidence interval 0.4, 6.5; p = 0.51). Roughly 30% of the sample had a documented relapse to drinking or drug use during the study, and these rates were similar in the topiramate (20/63; 31.8%) and placebo groups (18/66; 27.3%; p = 0.58). Results of a longitudinal logistic regression model examining time to any alcohol relapse revealed no medication effect. CONCLUSIONS: Topiramate at a daily dosage of up to 200 mg per day, combined with smoking cessation and medication adherence counseling, had no effects on smoking cessation or the prevention of alcohol or drug relapse in male smokers who were in early or sustained full remission from alcohol and motivated to make a quit attempt. Alternative approaches for treating this high-risk, dually dependent population are needed.


Assuntos
Abstinência de Álcool , Alcoolismo/tratamento farmacológico , Frutose/análogos & derivados , Abandono do Hábito de Fumar/métodos , Fumar/tratamento farmacológico , Tabagismo/tratamento farmacológico , Adulto , Alcoolismo/epidemiologia , Método Duplo-Cego , Frutose/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Fumar/epidemiologia , Tabagismo/epidemiologia , Topiramato
19.
Dev Biol ; 407(2): 321-30, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26417726

RESUMO

One of the more dramatic examples of cellular reorganization occurs during spermiogenesis in which a roughly spherical spermatid is transformed into a mature sperm cell. A highlight of this process involves nuclear remodeling whereby the round spermatid nucleus is sculpted into an elongated and polar structure. This transformation in nuclear architecture features chromatin condensation, changes in the composition and organization of the nuclear lamina and redistribution and elimination of nuclear pore complexes. The manchette, a cytoplasmic microtubule-based structure is thought to play a crucial role in the remodeling process. Here we show that SUN4, a spermatid nuclear membrane protein has an essential function in coupling the manchette to the nuclear periphery. In the absence of SUN4, manchette microtubules appear highly disorganized and the nucleus itself fails to elongate. Consequently, mice deficient in SUN4 display globozoospermia with associated infertility.


Assuntos
Núcleo Celular/metabolismo , Mamíferos/metabolismo , Proteínas Nucleares/metabolismo , Espermatogênese , Animais , Núcleo Celular/ultraestrutura , Feminino , Imunofluorescência , Deleção de Genes , Células HeLa , Recombinação Homóloga/genética , Humanos , Masculino , Camundongos Endogâmicos C57BL , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Membrana Nuclear/metabolismo , Membrana Nuclear/ultraestrutura , Ligação Proteica , Isoformas de Proteínas/metabolismo , Espermátides/metabolismo , Testículo/metabolismo , Testículo/ultraestrutura
20.
Am J Pathol ; 185(7): 2038-48, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26093985

RESUMO

Human placental trophoblasts can be considered pseudomalignant, with tightly controlled proliferation, apoptosis, and invasiveness. Gestational trophoblastic disease (GTD) represents a family of heterogeneous trophoblastic lesions with aberrant apoptotic and proliferative activities and dysregulation of cell signaling pathways. We characterize the oncogenic effects of factor that binds to the inducer of short transcripts of HIV-1 [FBI-1, alias POZ and Krüppel erythroid myeloid ontogenic factor (POKEMON)/ZBTB7A] in GTD and its role in promoting cell aggressiveness in vitro and tumor growth in vivo. IHC studies showed increased nuclear expression of FBI-1, including hydatidiform moles, choriocarcinoma (CCA), and placental site trophoblastic tumor, in GTD. In JAR and JEG-3 CCA cells, ectopic FBI-1 expression opposed apoptosis through repression of proapoptotic genes (eg, BAK1, FAS, and CASP8). FBI-1 overexpression also promoted Akt activation, as indicated by Akt-pS473 phosphorylation. FBI-1 overexpression promoted mobility and invasiveness of JEG-3 and JAR, but not in the presence of the phosphoinositide 3-kinase inhibitor LY294002. These findings suggest that FBI-1 could promote cell migration and invasion via phosphoinositide 3-kinase/Akt signaling. In vivo, nude mice injected with CCA cells with stable FBI-1 knockdown demonstrated reduced tumor growth compared with that in control groups. These findings suggest that FBI-1 is clinically associated with the progression of, and may be a therapeutic target in, GTD, owing to its diverse oncogenic effects on dysregulated trophoblasts.


Assuntos
Coriocarcinoma/patologia , Proteínas de Ligação a DNA/genética , Doença Trofoblástica Gestacional/patologia , Proteína Oncogênica v-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , Animais , Anticorpos , Apoptose , Testes de Carcinogenicidade , Movimento Celular , Coriocarcinoma/genética , Coriocarcinoma/metabolismo , Proteínas de Ligação a DNA/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Doença Trofoblástica Gestacional/genética , Doença Trofoblástica Gestacional/metabolismo , Humanos , Mola Hidatiforme/genética , Mola Hidatiforme/metabolismo , Mola Hidatiforme/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteína Oncogênica v-akt/genética , Fosfatidilinositol 3-Quinases/genética , Placenta/metabolismo , Gravidez , Coelhos , Fatores de Transcrição/metabolismo , Trofoblastos/metabolismo
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