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1.
J Infect Dis ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39042731

RESUMO

BACKGROUND: Sapovirus is an important cause of acute gastroenteritis in childhood. While vaccines against sapovirus may reduce gastroenteritis burden, a major challenge to their development is a lack of information about natural immunity. METHODS: We measured sapovirus-specific IgG in serum collected, between 2017 and 2020, of mothers soon after delivery and at 6 time points in Nicaraguan children until 3 years of age (n=112 dyads) using virus-like particles representing three sapovirus genotypes (GI.1, GI.2, GV.1). RESULTS: Sixteen (14.3%) of the 112 children experienced at least one sapovirus gastroenteritis episode, of which GI.1 was the most common genotype. Seroconversion to GI.1 and GI.2 was most common between 5 and 12 months of age, while seroconversion to GV.1 peaked at 18 to 24 months of age. All children who experienced sapovirus GI.1 gastroenteritis seroconverted and developed genotype-specific IgG. The impact of sapovirus exposure on population immunity was determined using antigenic cartography: newborns share their mothers' broadly binding IgG responses, which declined at 5 months of age and then increased as infants experienced natural sapovirus infections. CONCLUSION: By tracking humoral immunity to sapovirus over the first 3 years of life, this study provides important insights for the design and timing of future pediatric sapovirus vaccines.

2.
Pathobiology ; 90(6): 400-408, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37463569

RESUMO

INTRODUCTION: The clinical course of prostate cancer (PCa) is highly variable, ranging from indolent behavior to rapid metastatic progression. The Gleason score is widely accepted as the primary histologic assessment tool with significant prognostic value. However, additional biomarkers are required to better stratify patients, particularly those at intermediate risk. METHODS: In this study, we analyzed the expression of 86 cancer hallmark genes in 171 patients with PCa who underwent radical prostatectomy and focused on the outcome of the 137 patients with postoperative R0-PSA0 status. RESULTS: Low expression of the IGF1 and SRD52A, and high expression of TIMP2, PLAUR, S100A2, and CANX genes were associated with biochemical recurrence (BR), defined as an increase of prostate-specific antigen above 0.2 ng/mL. Furthermore, the analysis of the expression of 462 noncoding RNAs (ncRNA) in a sub-cohort of 39 patients with Gleason score 7 tumors revealed that high levels of expression of the ncRNAs LINC00624, LINC00593, LINC00482, and cd27-AS1 were significantly associated with BR. Our findings provide further evidence for tumor-promoting roles of ncRNAs in PCa patients at intermediate risk. The strong correlation between expression of LINC00624 and KRT8 gene, encoding a well-known cell surface protein present in PCa, further supports a potential contribution of this ncRNA to PCa progression. CONCLUSION: While larger and further studies are needed to define the role of these genes/ncRNA in PCa, our findings pave the way toward the identification of a subgroup of patients at intermediate risk who may benefit from adjuvant treatments and new therapeutic agents.


Assuntos
Neoplasias da Próstata , RNA Longo não Codificante , Masculino , Humanos , RNA Longo não Codificante/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/patologia , Próstata/patologia , Antígeno Prostático Específico , Prostatectomia , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/cirurgia , Gradação de Tumores
3.
J Infect Dis ; 225(1): 105-115, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34129046

RESUMO

BACKGROUND: The role of histo-blood group on the burden and severity of norovirus gastroenteritis in young infants has not been well documented. METHODS: Norovirus gastroenteritis was assessed in 443 Nicaraguan children followed from birth until 3 years of age. Stool samples were tested for norovirus by reverse-transcription quantitative polymerase chain reaction (RT-qPCR), and histo-blood group antigens (HBGAs) were determined by phenotyping of saliva and blood. Hazard ratios and predictors of norovirus acute gastroenteritis (AGE) outcome stratified by HBGA were estimated using Cox proportional hazards models. RESULTS: Of 1353 AGE episodes experienced by children, 229 (17%) tested positive for norovirus with an overall incidence of 21.9/100 child-years. Secretor children were infected as early as 2 months of age and had a higher incidence of norovirus GII compared to nonsecretor children (15.4 vs 4.1/100 child-years, P = .006). Furthermore, all GII.4 AGE episodes occurred in secretor children. Children infected with GI (adjusted odds ratio [aOR], 0.09 [95% confidence interval {CI}, .02-.33]) or non-GII.4 viruses (aOR, 0.2 [95% CI, .07-.6]) were less likely to have severe AGE compared to GII.4-infected children. CONCLUSIONS: Secretor status in children strongly influences the incidence of symptomatic norovirus infection in a genogroup or genotype-dependent manner and provides evidence that clinical severity in children depends on norovirus genotypes.


Assuntos
Antígenos de Grupos Sanguíneos , Infecções por Caliciviridae/epidemiologia , Fezes/virologia , Norovirus/isolamento & purificação , Saliva/virologia , Adulto , Coorte de Nascimento , Antígenos de Grupos Sanguíneos/efeitos adversos , Infecções por Caliciviridae/diagnóstico , Feminino , Gastroenterite/epidemiologia , Genótipo , Humanos , Incidência , Lactente , Masculino , Nicarágua/epidemiologia , Norovirus/genética , Vírus Norwalk , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem
4.
J Lipid Res ; 63(1): 100154, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34838542

RESUMO

Cancer cells may depend on exogenous serine, depletion of which results in slower growth and activation of adaptive metabolic changes. We previously demonstrated that serine and glycine (SG) deprivation causes loss of sphingosine kinase 1 (SK1) in cancer cells, thereby increasing the levels of its lipid substrate, sphingosine (Sph), which mediates several adaptive biological responses. However, the signaling molecules regulating SK1 and Sph levels in response to SG deprivation have yet to be defined. Here, we identify 1-deoxysphinganine (dSA), a noncanonical sphingoid base generated in the absence of serine from the alternative condensation of alanine and palmitoyl CoA by serine palmitoyl transferase, as a proximal mediator of SG deprivation in SK1 loss and Sph level elevation upon SG deprivation in cancer cells. SG starvation increased dSA levels in vitro and in vivo and in turn induced SK1 degradation through a serine palmitoyl transferase-dependent mechanism, thereby increasing Sph levels. Addition of exogenous dSA caused a moderate increase in intracellular reactive oxygen species, which in turn decreased pyruvate kinase PKM2 activity while increasing phosphoglycerate dehydrogenase levels, and thereby promoted serine synthesis. We further showed that increased dSA induces the adaptive cellular and metabolic functions in the response of cells to decreased availability of serine likely by increasing Sph levels. Thus, we conclude that dSA functions as an initial sensor of serine loss, SK1 functions as its direct target, and Sph functions as a downstream effector of cellular and metabolic adaptations. These studies define a previously unrecognized "physiological" nontoxic function for dSA.


Assuntos
Fosfotransferases (Aceptor do Grupo Álcool)
5.
Epidemiology ; 33(5): 650-653, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35700200

RESUMO

BACKGROUND: Norovirus and sapovirus cause a large burden of acute gastroenteritis (AGE) in young children. We assessed protection conferred by norovirus and sapovirus AGE episodes against future episodes. METHODS: Between June 2017 and July 2018, we recruited 444 newborns in León, Nicaragua. Weekly household surveys identified AGE episodes over 36 months, and AGE stools were tested by reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR) for norovirus genogroup (G)I/GII and sapovirus. We used recurrent-event Cox models and negative control methods to estimate protection conferred by first episodes, controlling for observed and unobserved risk factors, respectively. RESULTS: Sapovirus episodes conferred a 69% reduced hazard of subsequent episodes using the negative control method. Norovirus GI (hazard ratio [HR] = 0.67; 95% confidence interval [CI] = 0.31, 1.3) and GII (HR = 0.20; 95% CI = 0.04, 0.44) episodes also appeared highly protective. Protection against norovirus GII was enhanced following two episodes. CONCLUSIONS: Evidence of natural immunity in early childhood provides optimism for the future success of pediatric norovirus and sapovirus vaccines.


Assuntos
Infecções por Caliciviridae , Gastroenterite , Norovirus , Sapovirus , Coorte de Nascimento , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/prevenção & controle , Infecções por Caliciviridae/virologia , Pré-Escolar , Gastroenterite/epidemiologia , Gastroenterite/prevenção & controle , Gastroenterite/virologia , Genótipo , Humanos , Lactente , Recém-Nascido , Norovirus/genética , Sapovirus/genética
6.
FASEB J ; 35(2): e21284, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33484475

RESUMO

It has been well-established that cancer cells often display altered metabolic profiles, and recent work has concentrated on how cancer cells adapt to serine removal. Serine can be either taken exogenously or synthesized from glucose, and its regulation forms an important mechanism for nutrient integration. One of the several important metabolic roles for serine is in the generation of bioactive sphingolipids since it is the main substrate for serine palmitoyltransferase, the initial and rate-limiting enzyme in the synthesis of sphingolipids. Previously, serine deprivation has been connected to the action of the tumor suppressor p53, and we have previously published on a role for p53 regulating sphingosine kinase 1 (SK1), an enzyme that phosphorylates sphingosine to form sphingosine-1-phosphate (S1P). SK1 is a key enzyme in sphingolipid synthesis that functions in pro-survival and tumor-promoting pathways and whose expression is also often elevated in cancers. Here we show that SK1 was degraded during serine starvation in a time and dose-dependent manner, which led to sphingosine accumulation. This was independent of effects on p53 but required the action of the proteasome. Furthermore, we show that overexpression of SK1, to compensate for SK1 loss, was detrimental to cell growth under conditions of serine starvation, demonstrating that the suppression of SK1 under these conditions is adaptive. Mitochondrial oxygen consumption decreased in response to SK1 degradation, and this was accompanied by an increase in intracellular reactive oxygen species (ROS). Suppression of ROS with N-acteylcysteine resulted in suppression of the metabolic adaptations and in decreased cell growth under serine deprivation. The effects of SK1 suppression on ROS were mimicked by D-erythro-sphingosine, whereas S1P was ineffective, suggesting that the effects of loss of SK1 were due to the accumulation of its substrate sphingosine. This study reveals a new mechanism for regulating SK1 levels and a link of SK1 to serine starvation as well as mitochondrial function.


Assuntos
Adaptação Fisiológica , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Proteólise , Serina/deficiência , Regulação para Baixo , Células HCT116 , Humanos , Mitocôndrias/metabolismo , Oxigênio/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Serina/metabolismo , Proteína Supressora de Tumor p53/metabolismo
7.
Clin Infect Dis ; 72(5): e146-e153, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33515459

RESUMO

BACKGROUND: Neurodevelopmental outcomes of asymptomatic children exposed to Zika virus (ZIKV) in utero are not well characterized. METHODS: We prospectively followed 129 newborns without evidence of congenital Zika syndrome (CZS) up to 24 months of age. Participants were classified as ZIKV exposed or ZIKV unexposed. The Mullen Scales of Early Learning (MSEL) was administered in the participants' homes at 6, 12, 15, 18, 21, and 24 months of age by trained psychologists. Sociodemographic data, medical history, and infant anthropometry at birth were collected at each home visit. Our primary outcome was the Mullen Early Learning Composite Score (ECL) at 24 months of age between our 2 exposure groups. Secondary outcomes were differences in MSEL subscales over time and at 24 months. RESULTS: Of 129 infants in whom exposure status could be ascertained, 32 (24.8%) met criteria for in utero ZIKV exposure and 97 (75.2%) did not. There were no differences in maternal age, maternal educational attainment, birthweight, or gestational age at birth between the 2 exposure groups. The adjusted means and standard errors (SEs) for the ELC score between the ZIKV-exposed children compared to ZIKV-unexposed children were 91.4 (SE, 3.1) vs 96.8 (SE, 2.4) at 12 months and 93.3 (SE, 2.9) vs 95.9 (SE, 2.3) at 24 months. In a longitudinal mixed model, infants born to mothers with an incident ZIKV infection (P = .01) and low-birthweight infants (<2500 g) (P = .006) had lower composite ECL scores. CONCLUSIONS: In this prospective cohort of children without CZS, children with in utero ZIKV exposure had lower neurocognitive scores at 24 months.


Assuntos
Complicações Infecciosas na Gravidez , Infecção por Zika virus , Zika virus , Criança , Feminino , Humanos , Lactente , Recém-Nascido , Nicarágua/epidemiologia , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Estudos Prospectivos , Infecção por Zika virus/epidemiologia
8.
FASEB J ; 34(8): 10574-10589, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32568455

RESUMO

Cancer cells require extensive metabolic reprograming in order to provide the bioenergetics and macromolecular precursors needed to sustain a malignant phenotype. Mutant KRAS is a driver oncogene that is well-known for its ability to regulate the ERK and PI3K signaling pathways. However, it is now appreciated that KRAS can promote the tumor growth via upregulation of anabolic metabolism. We recently reported that oncogenic KRAS promotes a gene expression program of de novo lipogenesis in non-small cell lung cancer (NSCLC). To define the mechanism(s) responsible, we focused on the lipogenic transcription factor SREBP1. We observed that KRAS increases SREBP1 expression and genetic knockdown of SREBP1 significantly inhibited the cell proliferation of mutant KRAS-expressing cells. Unexpectedly, lipogenesis was not significantly altered in cells subject to SREBP1 knockdown. Carbon tracing metabolic studies showed a significant decrease in oxidative phosphorylation and RNA-seq data revealed a significant decrease in mitochondrial encoded subunits of the electron transport chain (ETC). Taken together, these data support a novel role, distinct from lipogenesis, of SREBP1 on mitochondrial function in mutant KRAS NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Mitocôndrias/metabolismo , Oncogenes/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Células A549 , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Células HEK293 , Humanos , Lipogênese/genética , Neoplasias Pulmonares/genética , Mutação/genética , Fosforilação Oxidativa , Proteínas Proto-Oncogênicas p21(ras)/genética , Transdução de Sinais/genética , Regulação para Cima/genética
9.
Epidemiol Infect ; 149: e247, 2021 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-35172912

RESUMO

In a Nicaraguan population-based cohort, SARS-CoV-2 seroprevalence reached 28% in the first 6 months of the country's epidemic and reached 35% 6 months later. Immune waning was uncommon. Individuals with a seropositive household member were over three times as likely to be seropositive themselves, suggesting the importance of household transmission.


Assuntos
COVID-19/epidemiologia , SARS-CoV-2/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nicarágua/epidemiologia , Prevalência , Estudos Soroepidemiológicos , População Urbana/estatística & dados numéricos , Adulto Jovem
10.
Prostate ; 80(13): 1108-1117, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32628318

RESUMO

BACKGROUND: Putative castration-resistant (CR) stem-like cells (CRSC) have been identified based on their ability to initiate and drive prostate cancer (PCa) recurrence following castration in vivo. Yet the relevance of these CRSC in the course of the human disease and particularly for the transition from hormone-naive (HN) to castration-resistance is unclear. In this study, we aimed at deciphering the significance of CRSC markers in PCa progression. METHODS: We constructed a tissue microarray comprising 112 matched HN and CR tissue specimens derived from 55 PCa patients. Expression of eight stemness-associated markers (ALDH1A1, ALDH1A3, ALDH3A1, BMI1, NANOG, NKX3.1, OCT4, SOX2) was assessed by immunohistochemistry and scored as a percentage of positive tumor cells. For each marker, the resulting scores were statistically analyzed and compared to pathological and clinical data associated with the samples. Unsupervised clustering analysis was performed to stratify patients according to the expression of the eight CRSC markers. Publicly-available transcriptional datasets comprising HN and CR PCa samples were interrogated to assess the expression of the factors in silico. RESULTS: Immunohistochemical assessment of paired samples revealed atypical patterns of expression and intra- and intertumor heterogeneity for a subset of CRSC markers. While the expression of particular CRSC markers was dynamic over time in some patients, none of the markers showed significant changes in expression upon the development of castration resistance (CR vs HN). Using unsupervised clustering approaches, we identified phenotypic subtypes based on the expression of specific stem-associated markers. In particular, we found (a) patterns of mutual exclusivity for ALDH1A1 and ALDH1A3 expression, which was also observed at the transcriptomic level in publicly-available PCa datasets, and (b) a phenotypic cluster associated with more aggressive features. Finally, by comparing HN and CR matched samples, we identified phenotypic cluster switches (ie, change of phenotypic cluster between the HN and CR state), that may be associated with clinical and predictive relevance. CONCLUSIONS: Our findings indicate stemness-associated patterns that are associated with the development of castration-resistance. These results pave the way toward a deeper understanding of the relevance of CRSC markers in PCa progression and resistance to androgen-deprivation therapy.


Assuntos
Biomarcadores Tumorais/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Neoplasias de Próstata Resistentes à Castração/patologia , Família Aldeído Desidrogenase 1/genética , Família Aldeído Desidrogenase 1/metabolismo , Aldeído Oxirredutases/genética , Aldeído Oxirredutases/metabolismo , Biomarcadores Tumorais/genética , Progressão da Doença , Heterogeneidade Genética , Humanos , Imuno-Histoquímica , Masculino , Neoplasias de Próstata Resistentes à Castração/genética , Retinal Desidrogenase/genética , Retinal Desidrogenase/metabolismo , Análise Serial de Tecidos
11.
J Pathol ; 247(2): 199-213, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30350422

RESUMO

Variable tumor cellularity can limit sensitivity and precision in comparative genomics because differences in tumor content can result in misclassifying truncal mutations as region-specific private mutations in stroma-rich regions, especially when studying tissue specimens of mediocre tumor cellularity such as lung adenocarcinomas (LUADs). To address this issue, we refined a nuclei flow-sorting approach by sorting nuclei based on ploidy and the LUAD lineage marker thyroid transcription factor 1 and applied this method to investigate genome-wide somatic copy number aberrations (SCNAs) and mutations of 409 cancer genes in 39 tumor populations obtained from 16 primary tumors and 21 matched metastases. This approach increased the mean tumor purity from 54% (range 7-89%) of unsorted material to 92% (range 79-99%) after sorting. Despite this rise in tumor purity, we detected limited genetic heterogeneity between primary tumors and their metastases. In fact, 88% of SCNAs and 80% of mutations were propagated from primary tumors to metastases and low allele frequency mutations accounted for much of the mutational heterogeneity. Even though the presence of SCNAs indicated a history of chromosomal instability (CIN) in all tumors, metastases did not have more SCNAs than primary tumors. Moreover, tumors with biallelic TP53 or ATM mutations had high numbers of SCNAs, yet they were associated with a low interlesional genetic heterogeneity. The results of our study thus provide evidence that most macroevolutionary events occur in primary tumors before metastatic dissemination and advocate for a limited degree of CIN over time and space in this cohort of LUADs. Sampling of primary tumors thus may suffice to detect most mutations and SCNAs. In addition, metastases but not primary tumors had seeded additional metastases in three of four patients; this provides a genomic rational for surgical treatment of such oligometastatic LUADs. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/secundário , Biomarcadores Tumorais/genética , Separação Celular/métodos , Citometria de Fluxo , Heterogeneidade Genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Adulto , Hibridização Genômica Comparativa , Variações do Número de Cópias de DNA , Feminino , Dosagem de Genes , Predisposição Genética para Doença , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Taxa de Mutação , Fenótipo , Estudos Retrospectivos , Análise Espaço-Temporal
12.
FASEB J ; : fj201800204, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29906244

RESUMO

Oncogenic Kras mutations are one of the most common alterations in non-small cell lung cancer and are associated with poor response to treatment and reduced survival. Driver oncogenes, such as Kras are now appreciated for their ability to promote tumor growth via up-regulation of anabolic pathways. Therefore, we wanted to identify metabolic vulnerabilities in Kras-mutant lung cancer. Using the Kras LSL-G12D lung cancer model, we show that mutant Kras drives a lipogenic gene-expression program. Stable-isotope analysis reveals that mutant Kras promotes de novo fatty acid synthesis in vitro and in vivo. The importance of fatty acid synthesis in Kras-induced tumorigenesis was evident by decreased tumor formation in Kras LSL-G12D mice after treatment with a fatty acid synthesis inhibitor. Importantly, with gain and loss of function models of mutant Kras, we demonstrate that mutant Kras potentiates the growth inhibitory effects of several fatty acid synthesis inhibitors. These studies highlight the potential to target mutant Kras tumors by taking advantage of the lipogenic phenotype induced by mutant Kras.-Singh, A., Ruiz, C., Bhalla, K., Haley, J. A., Li, Q. K., Acquaah-Mensah, G., Montal, E., Sudini, K. R., Skoulidis, F., Wistuba, I. I., Papadimitrakopoulou, V., Heymach, J. V., Boros, L. G., Gabrielson, E., Carretero, J., Wong, K.-k., Haley, J. D., Biswal, S., Girnun, G. D. De novo lipogenesis represents a therapeutic target in mutant Kras non-small cell lung cancer.

13.
J Pathol ; 244(3): 265-270, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29205775

RESUMO

BK polyomavirus has been linked to urothelial carcinoma in immunosuppressed patients. Here, we performed comprehensive genomic analysis of a BK polyomavirus-associated, metachronous, multifocal and metastatic micropapillary urothelial cancer in a kidney transplant recipient. Dissecting cancer heterogeneity by sorting technologies prior to array-comparative genomic hybridization followed by short tandem repeat analysis revealed that the metastatic urothelial cancer was of donor origin (4-year-old male). The top 50 cancer-associated genes showed no key driver mutations as assessed by next-generation sequencing. Whole genome sequencing and BK polyomavirus-specific amplification provided evidence for episomal and subgenomic chromosomally integrated BK polyomavirus genomes, which carried the same unique 17-bp deletion signature in the viral non-coding control region (NCCR). Whereas no role in oncogenesis could be attributed to the host gene integration in chromosome 1, the 17-bp deletion in the NCCR increased early viral gene expression, but decreased viral replication capacity. Consequently, urothelial cells were exposed to high levels of the transforming BK polyomavirus early proteins large tumour antigen and small tumour antigen from episomal and integrated gene expression. Surgery combined with discontinuation of immunosuppression resulted in complete remission, but sacrificed the renal transplant. Thus, this report links, for the first time, BK polyomavirus NCCR rearrangements with oncogenic transformation in urothelial cancer in immunosuppressed patients. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Vírus BK/genética , Biomarcadores Tumorais/genética , Transplante de Rim/efeitos adversos , Infecções por Polyomavirus/virologia , Doadores de Tecidos , Infecções Tumorais por Vírus/virologia , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/virologia , Urotélio/virologia , Adulto , Vírus BK/imunologia , Vírus BK/patogenicidade , Transformação Celular Viral , Pré-Escolar , Regulação Neoplásica da Expressão Gênica , Regulação Viral da Expressão Gênica , Interações Hospedeiro-Patógeno , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/efeitos adversos , Masculino , Metástase Neoplásica , Infecções por Polyomavirus/diagnóstico , Infecções por Polyomavirus/imunologia , Resultado do Tratamento , Infecções Tumorais por Vírus/diagnóstico , Infecções Tumorais por Vírus/imunologia , Neoplasias da Bexiga Urinária/imunologia , Neoplasias da Bexiga Urinária/patologia , Urotélio/imunologia , Urotélio/patologia
14.
J Pathol ; 245(1): 74-84, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29484655

RESUMO

Understanding the evolutionary mechanisms and genomic events leading to castration-resistant (CR) prostate cancer (PC) is key to improve the outcome of this otherwise deadly disease. Here, we delineated the tumour history of seven patients progressing to castration resistance by analysing matched prostate cancer tissues before and after castration. We performed genomic profiling of DNA content-based flow-sorted populations in order to define the different evolutionary patterns. In one patient, we discovered that a catastrophic genomic event, known as chromothripsis, resulted in multiple CRPC tumour populations with distinct, potentially advantageous copy number aberrations, including an amplification of FK506 binding protein 4 (FKBP4, also known as FKBP52), a protein enhancing the transcriptional activity of androgen receptor signalling. Analysis of FKBP4 protein expression in more than 500 prostate cancer samples revealed increased expression in CRPC in comparison to hormone-naïve (HN) PC. Moreover, elevated FKBP4 expression was associated with poor survival of patients with HNPC. We propose FKBP4 amplification and overexpression as a selective advantage in the process of tumour evolution and as a potential mechanism associated with the development of CRPC. Furthermore, FKBP4 interaction with androgen receptor may provide a potential therapeutic target in PC. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Cromotripsia , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores Androgênicos/metabolismo , Proteínas de Ligação a Tacrolimo/metabolismo , Idoso , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Pessoa de Meia-Idade , Transdução de Sinais/fisiologia
15.
J Lipid Res ; 59(11): 2126-2139, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30154231

RESUMO

The generation of most sphingolipids (SPLs) starts with condensation between serine and an activated long-chain fatty acid catalyzed by serine palmitoyltransferase (SPT). SPT can also use other amino acids to generate small quantities of noncanonical SPLs. The balance between serine-derived and noncanonical SPLs is pivotal; for example, hereditary sensory and autonomic neuropathy type I results from SPT mutations that cause an abnormal accumulation of alanine-derived SPLs. The regulatory mechanism for SPT amino acid selectivity and physiological functions of noncanonical SPLs are unknown. We investigated SPT selection of amino acid substrates by measuring condensation products of serine and alanine in yeast cultures and SPT use of serine and alanine in a TSC3 knockout model. We identified the Tsc3 subunit of SPT as a regulator of amino acid substrate selectivity by demonstrating its primary function in promoting alanine utilization by SPT and confirmed its requirement for the inhibitory effect of alanine on SPT utilization of serine. Moreover, we observed downstream metabolic consequences to Tsc3 loss: serine influx into the SPL biosynthesis pathway increased through Ypk1-depenedent activation of SPT and ceramide synthases. This Ypk1-dependent activation of serine influx after Tsc3 knockout suggests a potential function for deoxy-sphingoid bases in modulating Ypk1 signaling.


Assuntos
Alanina/metabolismo , Ceramidas/metabolismo , Saccharomyces cerevisiae/metabolismo , Serina C-Palmitoiltransferase/metabolismo , Esfingolipídeos/metabolismo , Espectrometria de Massas , Mutação/genética , Plasmídeos/genética , Serina/metabolismo , Especificidade por Substrato
16.
Lab Invest ; 98(11): 1487-1499, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30087457

RESUMO

Approximately 15% of patients with classical Hodgkin lymphoma (cHL) die after relapse or progressive disease. Comprehensive genetic characterization is required to better understand its molecular pathology and improve management. However, genetic information on cHL is hard to obtain mainly due to rare malignant Hodgkin- and Reed-Sternberg cells (HRSC), whose overall frequencies in the affected tissues ranges from 0.1 to 10%. Therefore, enrichment of neoplastic cells is necessary for the majority of genetic investigations. We have developed a new high-throughput method for marker-based enrichment of archival formalin-fixed and paraffin-embedded (FFPE) tissue-derived HRSC nuclei by fluorescence-assisted flow sorting (FACS) and successfully applied it on ten cHL cases. Genomic DNA extracted from sorted nuclei was used for targeted high-throughput sequencing (HTS) of 68 genes that are frequently affected in lymphomas. Chromosomal copy number aberrations were investigated by the Agilent SurePrint 180k microarray. Our method enabled HRSC nuclei enrichment to 40-90% in sorted populations. This level of enrichment was sufficient for reliable identification of tumor-specific mutations and copy number aberrations. Genetic analysis revealed that components of JAK-STAT signaling pathway were affected in all investigated tumors by frequent mutations of SOCS1 and STAT6 as well as copy number gains of JAK2. Involvement of nuclear factor-κB (NF-κB) pathway compounds was evident from recurrent gains of the locus containing the REL gene and mutations in TNFAIP3 and CARD11. Finally, genetic alterations of PD-L1 and B2M suggested immune evasion as mechanisms of oncogenesis in some patients. In this work, we present a new method for HRSC enrichment from FFPE tissue blocks by FACS and demonstrate the feasibility of a wide-scale genetic analysis by cutting-edge molecular methods. Our work opens the door to a large resource of archived clinical cHL samples and lays foundation to more complex studies aimed to answer important biological and clinical questions that are critical to improve cHL management.


Assuntos
Citometria de Fluxo/métodos , Doença de Hodgkin/patologia , Células de Reed-Sternberg , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
FASEB J ; 29(2): 494-507, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25381040

RESUMO

T-cadherin is an atypical glycosylphosphatidylinsoitol-anchored member of the cadherin superfamily of adhesion molecules. We found that T-cadherin overexpression in malignant (DU145) and benign (BPH-1) prostatic epithelial cell lines or silencing in the BPH-1 cell line, respectively, promoted or inhibited migration and spheroid invasion in collagen I gel and Matrigel. T-cadherin-dependent effects were associated with changes in cell phenotype: overexpression caused cell dissemination and loss of polarity evaluated by relative positioning of the Golgi/nuclei in cell groups, whereas silencing caused formation of compact polarized epithelial-like clusters. Epidermal growth factor receptor (EGFR) and IGF factor-1 receptor (IGF-1R) were identified as mediators of T-cadherin effects. These receptors per se had opposing influences on cell phenotype. EGFR activation with EGF or IGF-1R inhibition with NVP-AEW541 promoted dissemination, invasion, and polarity loss. Conversely, inhibition of EGFR with gefitinib or activation of IGF-1R with IGF-1 rescued epithelial morphology and decreased invasion. T-cadherin silencing enhanced both EGFR and IGF-1R phosphorylation, yet converted cells to the morphology typical for activated IGF-1R. T-cadherin effects were sensitive to modulation of EGFR or IGF-1R activity, suggesting direct involvement of both receptors. We conclude that T-cadherin regulates prostate cancer cell behavior by tuning the balance in EGFR/IGF-1R activity and enhancing the impact of IGF-1R.


Assuntos
Caderinas/metabolismo , Receptores ErbB/metabolismo , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Receptor IGF Tipo 1/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Núcleo Celular/metabolismo , Sobrevivência Celular , Colágeno/química , Combinação de Medicamentos , Gefitinibe , Inativação Gênica , Complexo de Golgi/metabolismo , Humanos , Laminina/química , Masculino , Invasividade Neoplásica , Fenótipo , Fosforilação , Proteoglicanas/química , Pirimidinas/química , Pirróis/química , Quinazolinas/química
18.
Nat Genet ; 39(5): 655-60, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17417639

RESUMO

Using an Affymetrix 10K SNP array to screen for gene copy number changes in breast cancer, we detected a single-gene amplification of the ESR1 gene, which encodes estrogen receptor alpha, at 6q25. A subsequent tissue microarray analysis of more than 2,000 clinical breast cancer samples showed ESR1 amplification in 20.6% of breast cancers. Ninety-nine percent of tumors with ESR1 amplification showed estrogen receptor protein overexpression, compared with 66.6% cancers without ESR1 amplification (P < 0.0001). In 175 women who had received adjuvant tamoxifen monotherapy, survival was significantly longer for women with cancer with ESR1 amplification than for women with estrogen receptor-expressing cancers without ESR1 amplification (P = 0.023). Notably, we also found ESR1 amplification in benign and precancerous breast diseases, suggesting that ESR1 amplification may be a common mechanism in proliferative breast disease and a very early genetic alteration in a large subset of breast cancers.


Assuntos
Neoplasias da Mama/genética , Receptor alfa de Estrogênio/genética , Amplificação de Genes/genética , Sequência de Bases , Feminino , Dosagem de Genes/genética , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
19.
Prostate ; 75(6): 585-92, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25585936

RESUMO

BACKGROUND: There is an urgent need for preclinical models of prostate cancer; however, clinically relevant patient-derived prostate cancer xenografts (PDXs) are demanding to establish. METHODS: Sixty-seven patients who were undergoing palliative transurethral surgery or radical prostatectomy for histologically confirmed, clinically relevant prostate cancer were included in the study. Fresh prostate cancer tissue was identified by frozen analysis in 48 patients. The cancer tissue was transplanted subcutaneously and under the renal capsule of NSG and NOG mice supplemented with human testosterone. All growing PDXs were evaluated by histology and immunohistochemistry. RESULTS: Early assessment of the animals at least three months after transplantation included 27/48 (56.3%) eligible PDX cohorts. PDX growth was detected in 10/27 (37%) mouse cohorts. Eight of the ten PDXs were identified as human donor derived lymphomas, including seven Epstein Barr virus (EBV)-positive diffuse large B-cell lymphomas and one EBV-negative peripheral T-cell lymphoma. One sample consisted of benign prostatic tissue, and one sample comprised a benign epithelial cyst. Prostate cancer was not detected in any of the samples. CONCLUSIONS: Tumors that arise within the first three months after prostate cancer xenografting may represent patient-derived EBV-positive lymphomas in up to 80% of the early growing PDXs when using triple knockout NSG immunocompromised mice. Therefore, lymphoma should be excluded in prostate cancer xenografts that do not resemble typical prostatic adenocarcinoma.


Assuntos
Linfoma/etiologia , Neoplasias da Próstata/etiologia , Animais , Herpesvirus Humano 4/isolamento & purificação , Humanos , Hospedeiro Imunocomprometido , Imuno-Histoquímica , Hibridização In Situ , Masculino , Camundongos , Camundongos Knockout , Repetições de Microssatélites , Transplante de Neoplasias , Transplante Heterólogo
20.
Hepatology ; 59(3): 911-23, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24114970

RESUMO

UNLABELLED: Hepatocellular carcinoma (HCC) is among the leading causes of cancer-related death. Despite the advances in diagnosis and management of HCC, the biology of this tumor remains poorly understood. Recent evidence highlighted long noncoding RNAs (lncRNAs) as crucial determinants of HCC development. In this study we report the lncRNA HOXA transcript at the distal tip (HOTTIP) as significantly up-regulated in HCC specimens. The HOTTIP gene is located in physical contiguity with HOXA13 and directly controls the HOXA locus gene expression by way of interaction with the WDR5/MLL complex. HOX genes encode transcription factors regulating embryonic development and cell fate. We previously described HOX genes deregulation to be involved in hepatocarcinogenesis. Indeed, we observed the marked up-regulation of HOXA13 in HCC. Here, by correlating clinicopathological and expression data, we demonstrate that the levels of HOTTIP and HOXA13 are associated with HCC patients' clinical progression and predict disease outcome. In contrast to the majority of similar studies, our data were obtained from snap-frozen needle HCC biopsies (n=52) matched with their nonneoplastic counterparts collected from patients who had not yet received any HCC-tailored therapeutic treatments at the time of biopsy. In addition, taking advantage of gain and loss of function experiments in liver cancer-derived cell lines (HuH-6 and HuH-7), we uncover a novel bidirectional regulatory loop between HOTTIP/HOXA13. CONCLUSION: Our study highlights the key role of HOTTIP and HOXA13 in HCC development by associating their expression with metastasis and survival in HCC patients, provides novel insights on the function of lncRNA-driven hepatocarcinogenesis, and paves the way for further investigation about the possible role of HOTTIP as a predictive biomarker of HCC.


Assuntos
Carcinoma Hepatocelular/genética , Proteínas de Homeodomínio/genética , Neoplasias Hepáticas/genética , RNA Longo não Codificante/genética , Idoso , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/secundário , Linhagem Celular Transformada , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Gradação de Tumores , Valor Preditivo dos Testes , RNA Interferente Pequeno/genética
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