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1.
Brain ; 147(7): 2368-2383, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38226698

RESUMEN

Loss-of-function variants in the triggering receptor expressed on myeloid cells 2 (TREM2) are responsible for a spectrum of neurodegenerative disorders. In the homozygous state, they cause severe pathologies with early onset dementia, such as Nasu-Hakola disease and behavioural variants of frontotemporal dementia (FTD), whereas heterozygous variants increase the risk of late-onset Alzheimer's disease (AD) and FTD. For over half of TREM2 variants found in families with recessive early onset dementia, the defect occurs at the transcript level via premature termination codons or aberrant splicing. The remaining variants are missense alterations thought to affect the protein; however, the underlying pathogenic mechanism is less clear. In this work, we tested whether these disease-associated TREM2 variants contribute to the pathology via altered splicing. Variants scored by SpliceAI algorithm were tested by a full-size TREM2 splicing reporter assay in different cell lines. The effect of variants was quantified by qRT-/RT-PCR and western blots. Nanostring nCounter was used to measure TREM2 RNA in the brains of NHD patients who carried spliceogenic variants. Exon skipping events were analysed from brain RNA-Seq datasets available through the Accelerating Medicines Partnership for Alzheimer's Disease Consortium. We found that for some Nasu-Hakola disease and early onset FTD-causing variants, splicing defects were the primary cause (D134G) or likely contributor to pathogenicity (V126G and K186N). Similar but milder effects on splicing of exons 2 and 3 were demonstrated for A130V, L133L and R136W enriched in patients with dementia. Moreover, the two most frequent missense variants associated with AD/FTD risk in European and African ancestries (R62H, 1% in Caucasians and T96K, 12% in Africans) had splicing defects via excessive skipping of exon 2 and overproduction of a potentially antagonistic TREM2 protein isoform. The effect of R62H on exon 2 skipping was confirmed in three independent brain RNA-Seq datasets. Our findings revealed an unanticipated complexity of pathogenic variation in TREM2, in which effects on post-transcriptional gene regulation and protein function often coexist. This necessitates the inclusion of computational and experimental analyses of splicing and mRNA processing for a better understanding of genetic variation in disease.


Asunto(s)
Enfermedad de Alzheimer , Glicoproteínas de Membrana , Empalme del ARN , Receptores Inmunológicos , Humanos , Receptores Inmunológicos/genética , Enfermedad de Alzheimer/genética , Glicoproteínas de Membrana/genética , Empalme del ARN/genética , Demencia Frontotemporal/genética , Demencia/genética , Predisposición Genética a la Enfermedad/genética
2.
Support Care Cancer ; 31(5): 292, 2023 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-37086362

RESUMEN

PURPOSE: All patients living with cancer, including those with metastatic cancer, are encouraged to be physically active. This paper examines the secondary endpoints of an aerobic exercise intervention for men with metastatic prostate cancer. METHODS: ExPeCT (Exercise, Prostate Cancer and Circulating Tumour Cells), was a multi-centre randomised control trial with a 6-month aerobic exercise intervention arm or a standard care control arm. Exercise adherence data was collected via heart rate monitors. Quality of life (FACT-P) and physical activity (self-administered questionnaire) assessments were completed at baseline, at 3 months and at 6 months. RESULTS: A total of 61 patients were included (69.4 ± 7.3 yr, body mass index 29.2 ± 5.8 kg/m2). The median time since diagnosis was 34 months (IQR 7-54). A total of 35 (55%) of participants had > 1 region affected by metastatic disease. No adverse events were reported by participants. There was no effect of exercise on quality of life (Cohen's d = - 0.082). Overall adherence to the supervised sessions was 83% (329 out of 396 possible sessions attended by participants). Overall adherence to the non-supervised home exercise sessions was 72% (months 1-3) and 67% (months 3-6). Modelling results for overall physical activity scores showed no significant main effect for the group (p-value = 0.25) or for time (p-value = 0.24). CONCLUSION: In a group of patients with a high burden of metastatic prostate cancer, a 6-month aerobic exercise intervention did not lead to change in quality of life. Further exercise studies examining the role of exercise for people living with metastatic prostate cancer are needed. TRIAL REGISTRATION: The trial was registered at clinicaltrials.gov (NCT02453139) on May 25th 2015.


Asunto(s)
Neoplasias de la Próstata , Calidad de Vida , Masculino , Humanos , Ejercicio Físico , Neoplasias de la Próstata/terapia , Terapia por Ejercicio/métodos , Encuestas y Cuestionarios
3.
Carcinogenesis ; 42(3): 395-404, 2021 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-32940666

RESUMEN

OBJECTIVES: Cancer patient outcomes and selection for novel therapies are heavily influenced by the immune contexture of the tumor microenvironment. Esophageal cancer is associated with poor outcomes. In contrast to colorectal cancer, where the immunoscore is increasingly used in prognostic staging, little is known about the immune cell populations in esophageal adenocarcinoma (EAC) and esophageal squamous cell carcinoma (SCC), and their clinical significance. METHODS: Tissue microarrays were constructed from resected tumor tissue of 72 EAC patients and 23 SCC patients. Immunohistochemical staining of CD3, CD8, CD56, CD68, CD45RO, CD69, IFN-γ, IL-10, IL-4, IL-17, TGF-ß, FOXP3 and CD107a was performed. Positivity was examined in both the stromal and epithelial compartments. Statistical analysis was performed to identify differences in immune cell infiltration and functional phenotypes between cancer subtypes and tissue compartments. RESULTS: This study identified that esophageal tumors are enriched with CD45RO+ and CD8+ cells and such positivity is significantly higher in SCC compared with EAC. Furthermore, the expression of CD45RO positively correlates with that of CD8 within the tumors of both patient cohorts, suggesting a dominance of memory cytotoxic T cells. This is supported by strong positivity of degranulation marker CD107a in the stromal compartment of EAC and SCC tumors. Cytokine staining revealed a mixed pro- and anti-inflammatory profile within EAC tumors. CONCLUSIONS: Esophageal tumors are enriched with memory cytotoxic T cells. Applying these measurements to a larger cohort will ascertain the clinical utility of assessing specific lymphocyte infiltrates in EAC and SCC tumors with regards to future immunotherapy use, patient prognosis and outcomes.


Asunto(s)
Adenocarcinoma/inmunología , Biomarcadores de Tumor/análisis , Neoplasias Esofágicas/inmunología , Carcinoma de Células Escamosas de Esófago/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo , Linfocitos T Citotóxicos/metabolismo , Adenocarcinoma/diagnóstico , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/metabolismo , Degranulación de la Célula/inmunología , Diagnóstico Diferencial , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/cirugía , Carcinoma de Células Escamosas de Esófago/diagnóstico , Carcinoma de Células Escamosas de Esófago/patología , Carcinoma de Células Escamosas de Esófago/cirugía , Esofagectomía , Esófago/inmunología , Esófago/patología , Esófago/cirugía , Femenino , Humanos , Memoria Inmunológica , Inmunofenotipificación , Antígenos Comunes de Leucocito/análisis , Antígenos Comunes de Leucocito/metabolismo , Linfocitos Infiltrantes de Tumor/inmunología , Masculino , Persona de Mediana Edad , Pronóstico , Linfocitos T Citotóxicos/inmunología , Análisis de Matrices Tisulares , Microambiente Tumoral/inmunología
4.
Am J Physiol Heart Circ Physiol ; 321(4): H716-H727, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34448635

RESUMEN

Spinal cord injury (SCI) impairs the cardiovascular responses to postural challenge, leading to the development of orthostatic hypotension (OH). Here, we apply lower body negative pressure (LBNP) to rodents with high-level SCI to demonstrate the usefulness of LBNP as a model for experimental OH studies, and to explore the effect of simulated OH on cardiovascular and cerebrovascular function following SCI. Male Wistar rats (n = 34) were subjected to a sham or T3-SCI surgery and survived into the chronic period postinjury (i.e., 8 wk). Cardiac function was tracked via ultrasound pre- to post-SCI to demonstrate the clinical utility of our model. At study termination, we conducted left-ventricular (LV) catheterization and insonated the middle cerebral artery to investigate the hemodynamic, cardiac, and cerebrovascular response to a mild dose of LBNP that is sufficient to mimic clinically defined OH in rats with T3-SCI but not sham animals. In response to mimicked OH, there was a greater decline in stroke volume, cardiac output, maximal LV pressure, and blood pressure in SCI compared with sham (P < 0.034), whereas heart rate was increased in sham but decreased in SCI (P < 0.029). SCI animals also had an exaggerated reduction in peak, minimum and mean middle cerebral artery flow, for a given change in blood pressure, in response to LBNP (P < 0.033), implying impaired dynamic cerebral autoregulation. Using a preclinical SCI model of OH, we demonstrate that complete high thoracic SCI impairs the cardiac response to OH and disrupts dynamic cerebral autoregulation.NEW & NOTEWORTHY This is the first use of LBNP to interrogate the cardiac and cerebrovascular responses to simulated OH in a preclinical study of SCI. Here, we demonstrate the utility of our simulated OH model and use it to demonstrate that SCI impairs the cardiac response to simulated OH and disrupts dynamic cerebrovascular autoregulation.


Asunto(s)
Circulación Cerebrovascular , Hemodinámica , Hipotensión Ortostática/fisiopatología , Arteria Cerebral Media/fisiopatología , Traumatismos de la Médula Espinal/fisiopatología , Médula Espinal/fisiopatología , Función Ventricular Izquierda , Adaptación Fisiológica , Animales , Modelos Animales de Enfermedad , Hipotensión Ortostática/etiología , Presión Negativa de la Región Corporal Inferior , Masculino , Ratas Wistar , Traumatismos de la Médula Espinal/complicaciones , Vértebras Torácicas , Factores de Tiempo
5.
Blood ; 134(2): 186-198, 2019 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-31010849

RESUMEN

Myeloid neoplasms, including myelodysplastic syndromes (MDS), are genetically heterogeneous disorders driven by clonal acquisition of somatic mutations in hematopoietic stem and progenitor cells (HPCs). The order of premalignant mutations and their impact on HPC self-renewal and differentiation remain poorly understood. We show that episomal reprogramming of MDS patient samples generates induced pluripotent stem cells from single premalignant cells with a partial complement of mutations, directly informing the temporal order of mutations in the individual patient. Reprogramming preferentially captured early subclones with fewer mutations, which were rare among single patient cells. To evaluate the functional impact of clonal evolution in individual patients, we differentiated isogenic MDS induced pluripotent stem cells harboring up to 4 successive clonal abnormalities recapitulating a progressive decrease in hematopoietic differentiation potential. SF3B1, in concert with epigenetic mutations, perturbed mitochondrial function leading to accumulation of damaged mitochondria during disease progression, resulting in apoptosis and ineffective erythropoiesis. Reprogramming also informed the order of premalignant mutations in patients with complex karyotype and identified 5q deletion as an early cytogenetic anomaly. The loss of chromosome 5q cooperated with TP53 mutations to perturb genome stability, promoting acquisition of structural and karyotypic abnormalities. Reprogramming thus enables molecular and functional interrogation of preleukemic clonal evolution, identifying mitochondrial function and chromosome stability as key pathways affected by acquisition of somatic mutations in MDS.


Asunto(s)
Reprogramación Celular , Evolución Clonal/genética , Células Madre Hematopoyéticas/patología , Síndromes Mielodisplásicos/genética , Células Madre Pluripotentes/patología , Humanos
6.
Am J Dermatopathol ; 41(5): 378-381, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30371512

RESUMEN

Chronic lymphoproliferative disorder of natural killer cells (CLPDNK) is a rare heterogenous indolent disorder comprising a persistent peripheral blood cell count of more than ≥2 × 10/L natural killer cells for over 6 months. We report an unusual case of cutaneous neural infiltration as a manifestation of CLPDNK. A 52-year-old woman with a background of CLPDNK was referred to dermatology with a painful rash primarily affecting her back. Skin biopsies revealed a neurotropic atypical lymphoid infiltration. Results of immunohistochemistry studies showed CD8, CD56, granzyme B, perforin positivity, and CD3 negativity in keeping with an atypical neurotropic lymphoid infiltrate consistent with cutaneous involvement by the patient's known CLPDNK. Cutaneous lesions and peripheral neuropathy in patients with CLPDNK have been reported; however, the involvement of cutaneous peripheral nerves as described in our case has not been reported before.


Asunto(s)
Células Asesinas Naturales/patología , Trastornos Linfoproliferativos/patología , Neoplasias del Sistema Nervioso Periférico/patología , Piel/patología , Femenino , Humanos , Persona de Mediana Edad
7.
Genome Res ; 25(1): 14-26, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25267526

RESUMEN

Whole-exome sequencing studies have identified common mutations affecting genes encoding components of the RNA splicing machinery in hematological malignancies. Here, we sought to determine how mutations affecting the 3' splice site recognition factor U2AF1 alter its normal role in RNA splicing. We find that U2AF1 mutations influence the similarity of splicing programs in leukemias, but do not give rise to widespread splicing failure. U2AF1 mutations cause differential splicing of hundreds of genes, affecting biological pathways such as DNA methylation (DNMT3B), X chromosome inactivation (H2AFY), the DNA damage response (ATR, FANCA), and apoptosis (CASP8). We show that U2AF1 mutations alter the preferred 3' splice site motif in patients, in cell culture, and in vitro. Mutations affecting the first and second zinc fingers give rise to different alterations in splice site preference and largely distinct downstream splicing programs. These allele-specific effects are consistent with a computationally predicted model of U2AF1 in complex with RNA. Our findings suggest that U2AF1 mutations contribute to pathogenesis by causing quantitative changes in splicing that affect diverse cellular pathways, and give insight into the normal function of U2AF1's zinc finger domains.


Asunto(s)
Neoplasias Hematológicas/genética , Proteínas Nucleares/genética , Empalme del ARN , Ribonucleoproteínas/genética , Apoptosis , Proteínas de la Ataxia Telangiectasia Mutada/genética , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Caspasa 8/genética , Caspasa 8/metabolismo , ADN (Citosina-5-)-Metiltransferasas/genética , ADN (Citosina-5-)-Metiltransferasas/metabolismo , Daño del ADN , Metilación de ADN , Proteína del Grupo de Complementación A de la Anemia de Fanconi/genética , Proteína del Grupo de Complementación A de la Anemia de Fanconi/metabolismo , Neoplasias Hematológicas/patología , Histonas/genética , Histonas/metabolismo , Humanos , Células K562 , Modelos Moleculares , Mutación , Proteínas Nucleares/metabolismo , Sitios de Empalme de ARN , Ribonucleoproteínas/metabolismo , Factor de Empalme U2AF , Dedos de Zinc , ADN Metiltransferasa 3B
8.
Prostate ; 77(12): 1288-1300, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28726241

RESUMEN

BACKGROUND: Between 20% and 35% of prostate cancer (PCa) patients who undergo treatment with curative intent (ie, surgery or radiation therapy) for localized disease will experience biochemical recurrence (BCR). Alterations in the insulin-like growth factor (IGF) axis and PTEN expression have been implicated in the development and progression of several human tumors including PCa. We examined the expression of the insulin receptor (INSR), IGF-1 receptor (IGF-1R), PTEN, and AKT in radical prostatectomy tissue of patients who developed BCR post-surgery. METHODS: Tissue microarrays (TMA) of 130 patients post-radical prostatectomy (65 = BCR, 65 = non-BCR) were stained by immunohistochemistry for INSR, IGF-1R, PTEN, and AKT using optimized antibody protocols. INSR, IGF1-R, PTEN, and AKT expression between benign and cancerous tissue, and different Gleason grades was assessed. Kaplan-Meier survival curves were used to examine the relationship between proteins expression and BCR. RESULTS: INSR (P < 0.001), IGF-1R (P < 0.001), and AKT (P < 0.05) expression was significantly increased and PTEN (P < 0.001) was significantly decreased in cancerous versus benign tissue. There was no significant difference in INSR, IGF-1R, or AKT expression in the cancerous tissue of non-BCR versus BCR patients (P = 0.149, P = 0.990, P = 0.399, respectively). There was a significant decrease in PTEN expression in the malignant tissue of BCR versus non-BCR patients (P = 0.011). Combinational analysis of the tissue proteins identified a combination of decreased PTEN and increased AKT or increased INSR was associated with worst outcome. We found that in each case, our hypothesized worst group was most likely to experience BCR and this was significant for combinations of PTEN+INSR and PTEN+AKT but not PTEN+IGF-1R (P = 0.023, P = 0.028, P = 0.078, respectively). CONCLUSIONS: Low PTEN is associated with BCR and this association is strongly modified by high INSR and high AKT expression. Measurement of these proteins could help inform appropriate patient selection for postoperative adjuvant therapy and prevent BCR.


Asunto(s)
Biomarcadores de Tumor/biosíntesis , Recurrencia Local de Neoplasia/metabolismo , Fosfohidrolasa PTEN/biosíntesis , Prostatectomía/tendencias , Neoplasias de la Próstata/metabolismo , Receptor IGF Tipo 1/biosíntesis , Adulto , Anciano , Estudios de Cohortes , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Valor Predictivo de las Pruebas , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía , Proteínas Proto-Oncogénicas c-akt/biosíntesis , Receptor de Insulina/biosíntesis
9.
Am J Physiol Cell Physiol ; 310(6): C436-45, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-26632601

RESUMEN

Chronic liver injury leads to fibrosis and cirrhosis. Cirrhosis, the end stage of chronic liver disease, is a leading cause of death worldwide and increases the risk of developing hepatocellular carcinoma. Currently, there is a lack of effective antifibrotic therapies to treat fibrosis and cirrhosis. Development of antifibrotic therapies requires an in-depth understanding of the cellular and molecular mechanisms involved in inflammation and fibrosis after hepatic injury. Two growth factor signaling pathways that regulate liver fibrosis are transforming growth factor-ß (TGFß) and platelet-derived growth factor (PDGF). However, their specific contributions to fibrogenesis are not well understood. Using a genetic model of liver fibrosis, we investigated whether the canonical TGFß signaling pathway was necessary for fibrogenesis. PDGF-C transgenic (PDGF-C Tg) mice were intercrossed with mice that lack Smad3, and molecular and histological fibrosis was analyzed. PDGF-C Tg mice that also lacked Smad3 had less fibrosis and improved liver lobule architecture. Loss of Smad3 also reduced expression of collagen genes, which were induced by PDGF-C, but not the expression of genes frequently associated with hepatic stellate cell (HSC) activation. In vitro HSCs isolated from Smad3-null mice proliferated more slowly than cells from wild-type mice. Taken together, these findings indicate that PDGF-C activates TGFß/Smad3 signaling pathways to regulate HSC proliferation, collagen production and ultimately fibrosis. In summary, these results suggest that inhibition of both PDGF and TGFß signaling pathways may be required to effectively attenuate fibrogenesis in patients with chronic liver disease.


Asunto(s)
Cirrosis Hepática/metabolismo , Linfocinas/metabolismo , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Proteína smad3/metabolismo , Animales , Carcinoma Hepatocelular/metabolismo , Proliferación Celular/fisiología , Células Cultivadas , Femenino , Células Estrelladas Hepáticas/metabolismo , Hepatocitos/metabolismo , Hígado/fisiología , Neoplasias Hepáticas/metabolismo , Masculino , Ratones , Ratones Noqueados , Ratones Transgénicos , Ratas , Transducción de Señal/fisiología , Factor de Crecimiento Transformador beta/metabolismo
10.
Biochim Biophys Acta ; 1842(2): 318-25, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24269585

RESUMEN

Platelet-derived growth factors (PDGFs) are critical for development; their over-expression is associated with fibrogenesis. Full-length PDGF-C is secreted as an inactive dimer, requiring cleavage to allow receptor binding. Previous studies indicate that tissue-type plasminogen activator (tPA) is the specific protease that performs this cleavage; in vivo confirmation is lacking. We demonstrate that primary hepatocytes from tpa KO mice produce less cleaved active PDGF-CC than do wild type hepatocytes, suggesting that tPA is critical for in vitro activation of this growth factor. We developed mice that over-express full-length human PDGF-C in the liver; these mice develop progressive liver fibrosis. To test whether tPA is important for cleavage and activation of PDGF-C in vivo, we intercrossed PDGF-C transgenic (Tg) and tpa knock-out (KO) mice, anticipating that lack of tPA would result in decreased fibrosis due to lack of hPDGF-C cleavage. To measure levels of cleaved, dimerized PDGF-CC in sera, we developed an ELISA that specifically detects cleaved PDGF-CC. We report that the absence of tpa does not affect the phenotype of `PDGF-C Tg mice. PDGF-C Tg mice lacking tPA have high serum levels of cleaved growth factor, significant liver fibrosis, and gene expression alterations similar to those of PDGF-C Tg mice with intact tPA. Furthermore, urokinase plasminogen activator and plasminogen activator inhibitor-1 expression are increased in PDGF-C Tg; tpa KO mice. Our ELISA data suggest a difference between in vitro and in vivo activation of this growth factor, and our mouse model confirms that multiple proteases cleave and activate PDGF-C in vivo.


Asunto(s)
Hepatocitos/metabolismo , Cirrosis Hepática/genética , Linfocinas/genética , Factor de Crecimiento Derivado de Plaquetas/genética , Activador de Tejido Plasminógeno/genética , Animales , Células Cultivadas , Ensayo de Inmunoadsorción Enzimática , Perfilación de la Expresión Génica , Hepatocitos/citología , Humanos , Hígado/metabolismo , Hígado/patología , Cirrosis Hepática/metabolismo , Linfocinas/sangre , Linfocinas/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Inhibidor 1 de Activador Plasminogénico/genética , Inhibidor 1 de Activador Plasminogénico/metabolismo , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Proteolisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Activador de Tejido Plasminógeno/metabolismo , Activador de Plasminógeno de Tipo Uroquinasa/genética , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo
11.
N C Med J ; 76(5): 328-31, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26946868

RESUMEN

To assist the community provider in understanding and accessing Veterans Affairs (VA) resources, this commentary describes basic information regarding care of veterans. It highlights questions that may be incorporated into routine history taking, provides military culture resources, and clarifies pharmaceutical benefits. Table 2 is a quick reference guide to locate VA-based information on the Internet.


Asunto(s)
Servicios de Salud Comunitaria/organización & administración , Relaciones Comunidad-Institución , United States Department of Veterans Affairs/organización & administración , Veteranos , Humanos , North Carolina , Estados Unidos
12.
Int J Cancer ; 134(4): 778-88, 2014 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-23929039

RESUMEN

Cirrhosis is the primary risk factor for the development of hepatocellular carcinoma (HCC), yet the mechanisms by which cirrhosis predisposes to carcinogenesis are poorly understood. Using a mouse model that recapitulates many aspects of the pathophysiology of human liver disease, we explored the mechanisms by which changes in the liver microenvironment induce dysplasia and HCC. Hepatic expression of platelet-derived growth factor C (PDGF-C) induces progressive fibrosis, chronic inflammation, neoangiogenesis and sinusoidal congestion, as well as global changes in gene expression. Using reporter mice, immunofluorescence, immunohistochemistry and liver cell isolation, we demonstrate that receptors for PDGF-CC are localized on hepatic stellate cells (HSCs), which proliferate, and transform into myofibroblast-like cells that deposit extracellular matrix and lead to production of growth factors and cytokines. We demonstrate induction of cytokine genes at 2 months, and stromal cell-derived hepatocyte growth factors that coincide with the onset of dysplasia at 4 months. Our results support a paracrine signaling model wherein hepatocyte-derived PDGF-C stimulates widespread HSC activation throughout the liver leading to chronic inflammation, liver injury and architectural changes. These complex changes to the liver microenvironment precede the development of HCC. Further, increased PDGF-CC levels were observed in livers of patients with nonalcoholic fatty steatohepatitis and correlate with the stage of disease, suggesting a role for this growth factor in chronic liver disease in humans. PDGF-C transgenic mice provide a unique model for the in vivo study of tumor-stromal interactions in the liver.


Asunto(s)
Carcinoma Hepatocelular/patología , Hígado Graso/patología , Células Estrelladas Hepáticas/patología , Neoplasias Hepáticas/patología , Linfocinas/metabolismo , Comunicación Paracrina , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Células del Estroma/patología , Animales , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Estudios de Cohortes , Citocinas/genética , Citocinas/metabolismo , Hígado Graso/genética , Hígado Graso/metabolismo , Técnica del Anticuerpo Fluorescente , Perfilación de la Expresión Génica , Células Estrelladas Hepáticas/metabolismo , Hepatocitos/metabolismo , Hepatocitos/patología , Humanos , Técnicas para Inmunoenzimas , Inflamación/genética , Inflamación/metabolismo , Inflamación/patología , Hígado/metabolismo , Hígado/patología , Cirrosis Hepática/genética , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Linfocinas/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Enfermedad del Hígado Graso no Alcohólico , Análisis de Secuencia por Matrices de Oligonucleótidos , Factor de Crecimiento Derivado de Plaquetas/genética , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células del Estroma/metabolismo
13.
FASEB J ; 27(6): 2367-81, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23463699

RESUMEN

Chronic obstructive pulmonary disease (COPD) is associated with persistent inflammation and oxidative stress in susceptible individuals. Using microarray analysis of bronchial biopsy samples from patients with COPD and controls, we identified Wnt4 as being up-regulated in COPD. Analysis of bronchial biopsy samples showed a very strong correlation between Wnt4 and IL8 gene expression, suggesting that Wnt4 plays a role in chronic lung inflammation. In vitro, Wnt4 induced proliferation and inflammation in human epithelial cells (BEAS-2B) and normal primary human bronchial epithelial cells in a concentration-dependent manner. This effect was enhanced in the presence of interleukin-1ß (IL-1ß) as a result of activation of the p38 and c-Jun NH2-terminal kinase mitogen-activated protein kinase pathways. Hydrogen peroxide, but not proinflammatory stimuli, up-regulated Wnt4 expression in epithelial cells. In monocytic THP-1 and primary airway smooth muscle cells, Wnt4 induced inflammation and enhanced the inflammatory response to lipopolysaccharide and IL-1ß but did not induce proliferation. In addition, these other cell types did not have enhanced Wnt4 expression in response to hydrogen peroxide. Our results indicate that airway epithelial activation, due to oxidative stress, may lead to Wnt4 induction. Wnt4, in turn, acts through the noncanonical pathway to activate epithelial cell remodeling and IL8 gene expression, leading to neutrophil infiltration and inflammation.


Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica/genética , Proteína Wnt4/metabolismo , Adulto , Anciano , Animales , Bronquios/metabolismo , Estudios de Casos y Controles , Línea Celular , Células Cultivadas , Modelos Animales de Enfermedad , Femenino , Humanos , Mediadores de Inflamación/metabolismo , Mediadores de Inflamación/fisiología , Interleucina-8/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/etiología , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Regulación hacia Arriba , Proteína Wnt4/antagonistas & inhibidores , Proteína Wnt4/biosíntesis
14.
Ann Diagn Pathol ; 18(3): 181-6, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24768494

RESUMEN

Gallbladder dysplasia and carcinoma (GBDC) vary greatly in incidence worldwide. We aimed to determine their prevalence in an Irish population, to assess the influence of tissue sampling protocols upon GBDC diagnosis, and to correlate various macroscopic and microscopic features with GBDC. We retrospectively reviewed histology reports of cholecystectomy specimens accessioned from 2000 to 2013. A total of 2522 cholecystectomy reports were reviewed, from 1860 female and 662 male patients. Male patients were significantly older (54.8 vs 46.8 years). There were 29 cases of dysplasia (1.15%) and 12 cases of carcinoma (0.48%), of which 10 were primary gallbladder cancers (0.4%). In 83.4% of cases, there was pathologic or radiologic evidence of cholelithiasis. Histologic findings included chronic (91.1%) or acute (15.4%) cholecystitis, cholesterosis (10.9%), adenomyomatous hyperplasia (2.1%), xanthogranulomatous inflammation (2.02%), and "porcelain" gallbladder (0.2%). Patients with GBDC were more likely to have a macroscopically identifiable lesion (29.4% vs 1.8%, positive predictive value, 18.18%, negative predictive value, 99.03%). Gallbladder dysplasia and carcinoma patients also had larger gallstones (median, 19 vs 12 mm) and were more likely to have adenomyomatous hyperplasia (8.8% vs 2.05%). When cases with a macroscopically identifiable lesion or clinical details suggestive of a gallbladder tumour were excluded (n = 2385), GBDC was significantly more frequently diagnosed if multiple tissue blocks had been sampled (2.91% vs 0.76%; relative risk (RR), 3.836). Rates of GBDC in Irish cholecystectomy specimens are low. The absence of a macroscopically identifiable lesion has a high (but not 100%) negative predictive value for GBDC. Sampling with more than 1 block significantly increases pickup rates of GBDC in these cases.


Asunto(s)
Adenomioma , Colecistectomía/estadística & datos numéricos , Colecistitis , Colelitiasis , Neoplasias de la Vesícula Biliar , Vesícula Biliar/patología , Adenomioma/epidemiología , Adenomioma/patología , Adenomioma/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Niño , Colecistitis/epidemiología , Colecistitis/patología , Colecistitis/cirugía , Colelitiasis/epidemiología , Colelitiasis/patología , Colelitiasis/cirugía , Femenino , Neoplasias de la Vesícula Biliar/epidemiología , Neoplasias de la Vesícula Biliar/patología , Neoplasias de la Vesícula Biliar/cirugía , Humanos , Incidencia , Irlanda/epidemiología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
15.
Eur Respir J ; 42(6): 1633-45, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23520313

RESUMEN

Research into the pathogenesis underlying the development of idiopathic pulmonary fibrosis is hampered by a repertoire of animal models that fail to recapitulate all the features of the human disease. Better use and understanding of what the animal models represent may improve clinical predictability. We interrogated ex vivo micro-computed tomography (CT) as a novel end-point measure in the mouse model of bleomycin-induced lung fibrosis (BILF), and to evaluate a therapeutic dosing regimen for preclinical drug evaluation. A detailed characterisation of BILF was performed using standard end-point measures (lung hydroxyproline and histology). High resolution micro-CT (∼13.7 µm voxel size) was evaluated for quantifying the extent and severity of lung fibrosis. The period from 14 to 28 days following bleomycin instillation represents progression of established fibrosis. A therapeutic dosing regimen during this period was validated using a transforming growth factor-ß receptor-1 kinase inhibitor, and micro-CT provided a highly sensitive and quantitative measure of fibrosis. Moreover, fibrotic lesions did not completely resolve, but instead persisted for ≥6 months following a single insult with bleomycin. Ex vivo micro-CT analysis of BILF allows robust evaluation of therapeutic dosing once fibrosis is already well established, requiring fewer mice than conventional biochemical end-points.


Asunto(s)
Bleomicina/efectos adversos , Evaluación Preclínica de Medicamentos , Fibrosis Pulmonar/inducido químicamente , Microtomografía por Rayos X/métodos , Animales , Cromatografía Líquida de Alta Presión , Colágeno/análisis , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Fibrosis , Humanos , Imidazoles/química , Pulmón/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Quinoxalinas/química , Receptor Tipo I de Factor de Crecimiento Transformador beta , Receptores de Factores de Crecimiento Transformadores beta/antagonistas & inhibidores , Resultado del Tratamiento
16.
Breast J ; 19(3): 319-24, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23600490

RESUMEN

Mammographic calcification is an important radiologic feature of early breast carcinoma whose index of suspicion for malignancy may be reported by a five-tier R-category system. This study aims to describe the histologic diagnoses underlying screen-detected mammographic calcifications using both digital and screen-film mammography, and to correlate these findings with radiologic R-categories. Patients attending the Merrion Breast Screening Unit in Dublin between 2000 and 2011 were identified, who underwent needle-core biopsy for assessment of mammographic calcifications without associated mass or architectural distortion. Radiologic R-category was correlated with biopsy and excision histology reports. A total of 776 cases of calcification were identified, involving 769 individual patients. The radiologic R-categories were as follows: R3 513 (66.1%), R4 192 (24.7%), R5 71 (9.1%). The positive predictive values for malignancy were R3 32.6%, R4 69.8%, R5 95.8%. Several histologic features of DCIS were associated with R5 rather than R3 radiology: high nuclear grade, solid or cribriform architecture, necrosis, periductal inflammation or fibrosis, and associated microinvasive or invasive carcinoma. Mammographic lesions and histologic whole and invasive tumors increased in size from R3 to R5. Radiologic size of calcifications correlated with whole (but not invasive) tumor size, although it tended to underestimate it by several millimeters. Digital-detected calcifications were more likely than screen-film detected to be categorized as R3 and less likely R4 or R5, and there was no significant difference in positive predictive value between the two imaging techniques in any R-category. In conclusion, histologic features of DCIS, in particular those associated with high grade, are associated with R5 radiology. There is no significant difference in positive predictive value for malignancy in any R-category between digital and screen-film mammography.


Asunto(s)
Neoplasias de la Mama/patología , Calcinosis/patología , Carcinoma Intraductal no Infiltrante/patología , Mamografía , Biopsia con Aguja Gruesa , Neoplasias de la Mama/diagnóstico por imagen , Calcinosis/diagnóstico por imagen , Carcinoma Intraductal no Infiltrante/diagnóstico por imagen , Femenino , Humanos , Persona de Mediana Edad , Clasificación del Tumor
17.
Br J Clin Pharmacol ; 74(6): 1023-32, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22469312

RESUMEN

AIMS: Lipopolysaccharide (LPS) is a TLR4 agonist which activates NFκB dependent cytokine production. We investigated LPS inhalation in healthy smokers as a model of COPD bacterial exacerbations. We studied safety, reproducibility, the translocation of the NFκB subunit p65 in sputum cells and changes in systemic biomarkers of inflammation. METHODS: Twelve smokers inhaled 5 and 30 µg LPS and safety was monitored over 24 h. IL-6, CRP, CCl-18, SP-D, CC-16 and ß-defensin 2 were measured in serum samples collected at baseline, 4, 8 and 24 h. Sputum was induced at baseline, 6 and 24 h for cell counts and p65 expression. Repeated challenges were performed after a 2 week interval in 10 smokers. RESULTS: LPS inhalation was well tolerated. Significant increases occurred in sputum neutrophil counts with both doses, with a maximum increase of 21.5% at 6 h after 30 µg which was reproducible, r(i ) (intraclass correlation coefficient) = 0.88. LPS increased sputum cell nuclear p65 translocation and phospho-p65 expression. All of the serum biomarkers increased following challenge but with different temporal patterns. DISCUSSION: Inhaled LPS challenge in smokers causes pulmonary and systemic inflammation that involves NFκB activation. This appears to be a suitable model for studying bacterial exacerbations of COPD.


Asunto(s)
Lipopolisacáridos/administración & dosificación , Pulmón/efectos de los fármacos , Enfermedad Pulmonar Obstructiva Crónica/inducido químicamente , Fumar , Esputo/inmunología , Administración por Inhalación , Biomarcadores/metabolismo , Quimiocinas CC/sangre , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Exposición por Inhalación , Pulmón/inmunología , Masculino , Persona de Mediana Edad , Neutrófilos/inmunología , Enfermedad Pulmonar Obstructiva Crónica/sangre , Proteína D Asociada a Surfactante Pulmonar/sangre , Factor de Transcripción ReIA/sangre , Uteroglobina/sangre , beta-Defensinas/sangre
18.
Dig Surg ; 29(4): 331-48, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23075625

RESUMEN

BACKGROUND: Gastric neuroendocrine tumours (NETs) are increasingly recognised, and management decisions may be difficult due to an incomplete understanding of aetiology, natural history and optimum therapy. This article presents a current understanding based on recent advances in epidemiology, classification, molecular profiling, and treatment. METHODS: Relevant medical literature was identified from searches of PubMed and references cited in appropriate articles identified. Selection of articles was based on peer review, journal and relevance. RESULTS: Gastric NETs may be divided into three clinical prognostic groups: type I is associated with autoimmune atrophic gastritis and hypergastrinaemia, type II is associated with Zollinger-Ellison syndrome, and type III lesions are gastrin-independent, have the greatest metastatic potential and poorest prognosis. There has been an increased frequency of gastric NETs reported. Management approaches have evolved in parallel with advances in endoscopic staging and surgery, as well as improved understanding of the biology and natural history of NETs. CONCLUSIONS: Gastric NETs present a spectrum of activity from indolent tumours to metastatic malignancy. Treatment decisions for patients must be individualised and are best managed by a multidisciplinary team approach. The current evidence base is limited to small series and efforts to treat patients within clinical networks of expertise are warranted.


Asunto(s)
Tumores Neuroendocrinos , Neoplasias Gástricas , Síndrome de Zollinger-Ellison , Algoritmos , Gastrectomía , Salud Global , Humanos , Incidencia , Irlanda/epidemiología , Estadificación de Neoplasias , Tumores Neuroendocrinos/clasificación , Tumores Neuroendocrinos/diagnóstico , Tumores Neuroendocrinos/epidemiología , Tumores Neuroendocrinos/terapia , Pronóstico , Factores de Riesgo , Neoplasias Gástricas/clasificación , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/epidemiología , Neoplasias Gástricas/terapia , Resultado del Tratamiento , Síndrome de Zollinger-Ellison/diagnóstico , Síndrome de Zollinger-Ellison/epidemiología , Síndrome de Zollinger-Ellison/terapia
19.
BMJ Case Rep ; 15(11)2022 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-36446475

RESUMEN

Enterobius vermicularis infection is typically observed in paediatric patients and manifests with perianal pruritus, but other manifestations or ectopic presentations have been reported in the literature. We present the case of a man in his 60ss with a large-bowel obstruction with symptoms including a 4-day history of progressive abdominal pain, distension, vomiting and absolute constipation. On examination, his abdomen was distended with tinkling bowel sounds on auscultation. Cross-sectional imaging demonstrated an obstructing mass in the distal descending colon. An emergency laparoscopic Hartmann's procedure was performed and the patient made an uneventful recovery. An intraoperative colonoscopy demonstrated numerous white threadworms in the colon. Histological analysis demonstrated a pseudotumour related to Enterobius vermicularis infection. This case represents a rare differential diagnosis for a large-bowel obstruction.


Asunto(s)
Cavidad Abdominal , Enterobiasis , Masculino , Animales , Humanos , Niño , Enterobius , Enterobiasis/complicaciones , Enterobiasis/diagnóstico , Enterobiasis/cirugía , Colostomía , Colon
20.
J Cancer Surviv ; 2022 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-36376712

RESUMEN

PURPOSE: To synthesize the barriers to primary care provider (PCP)-led cancer survivorship care (≤ 5 years after initial cancer treatment) experienced by healthcare systems around the world, and to explore potential solutions that would succeed within a developed country. METHODS: A scoping review of peer-reviewed articles and grey literature was conducted. Four electronic databases (Medline, Embase, Web of Science Core Collection, and Google Scholar) were searched for articles prior to April 2021. RESULTS: Ninety-seven articles published across the globe (USA, Canada, Australia, European Union, and UK) met the review inclusion/exclusion criteria. The four most frequently discussed barriers to PCP-led survivorship care in healthcare systems were as follows: (1) insufficient communication between PCPs and cancer specialists, (2) limited PCP knowledge, (3) time restrictions for PCPs to provide comprehensive survivorship care, and (4) a lack of resources (e.g., survivorship care guidelines). Potential solutions to combat these barriers were as follows: (1) improving interdisciplinary communication, (2) bolstering PCP education, and (3) providing survivorship resources. CONCLUSIONS: This scoping review identified and summarized key barriers and solutions to the provision of PCP-led cancer survivorship care. Importantly, the findings from this review provide insight and direction to guide optimization of cancer care practice within BC's healthcare system. IMPLICATIONS FOR CANCER SURVIVORS: Optimizing the PCP-led survivorship care model will be a valuable contribution to the field of cancer survivorship care and will hopefully lead to more widespread use of this model, ultimately lessening the growing demand for cancer-specific care by cancer specialists.

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