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1.
Growth Factors ; : 1-13, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38299881

RESUMEN

Breast cancer represents a collection of pathologies with different molecular subtypes, histopathology, risk factors, clinical behavior, and responses to treatment. "Basal-like" breast cancers predominantly lack the receptors for estrogen and progesterone (ER/PR), lack amplification of human epidermal growth factor receptor 2 (HER2) but account for 10-15% of all breast cancers, are largely insensitive to targeted treatment and represent a disproportionate number of metastatic cases and deaths. Analysis of interleukin (IL)-3 and the IL-3 receptor subunits (IL-3RA + CSF2RB) reveals elevated expression in predominantly the basal-like group. Further analysis suggests that IL-3 itself, but not the IL-3 receptor subunits, associates with poor patient outcome. Histology on patient-derived xenografts supports the notion that breast cancer cells are a significant source of IL-3 that may promote disease progression. Taken together, these observations suggest that IL-3 may be a useful marker in solid tumors, particularly triple negative breast cancer, and warrants further investigation into its contribution to disease pathogenesis.

2.
Nat Commun ; 14(1): 5546, 2023 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-37684239

RESUMEN

Chimeric antigen receptor (CAR)-T cell immunotherapy is a novel treatment that genetically modifies the patients' own T cells to target and kill malignant cells. However, identification of tumour-specific antigens expressed on multiple solid cancer types, remains a major challenge. P2X purinoceptor 7 (P2X7) is a cell surface expressed ATP gated cation channel, and a dysfunctional version of P2X7, named nfP2X7, has been identified on cancer cells from multiple tissues, while being undetectable on healthy cells. We present a prototype -human CAR-T construct targeting nfP2X7 showing potential antigen-specific cytotoxicity against twelve solid cancer types (breast, prostate, lung, colorectal, brain and skin). In xenograft mouse models of breast and prostate cancer, CAR-T cells targeting nfP2X7 exhibit robust anti-tumour efficacy. These data indicate that nfP2X7 is a suitable immunotherapy target because of its broad expression on human tumours. CAR-T cells targeting nfP2X7 have potential as a wide-spectrum cancer immunotherapy for solid tumours in humans.


Asunto(s)
Neoplasias de la Próstata , Masculino , Humanos , Animales , Ratones , Inmunoterapia , Encéfalo , Mama , Membrana Celular , Modelos Animales de Enfermedad
3.
Cell Death Dis ; 13(10): 911, 2022 10 29.
Artículo en Inglés | MEDLINE | ID: mdl-36309486

RESUMEN

Type 1 diabetes is a complex disease characterized by the lack of endogenous insulin secreted from the pancreatic ß-cells. Although ß-cell targeted autoimmune processes and ß-cell dysfunction are known to occur in type 1 diabetes, a complete understanding of the cell-to-cell interactions that support pancreatic function is still lacking. To characterize the pancreatic endocrine compartment, we studied pancreata from healthy adult donors and investigated a single cell surface adhesion molecule, desmoglein-2 (DSG2). Genetically-modified mice lacking Dsg2 were examined for islet cell mass, insulin production, responses to glucose, susceptibility to a streptozotocin-induced mouse model of hyperglycaemia, and ability to cure diabetes in a syngeneic transplantation model. Herein, we have identified DSG2 as a previously unrecognized adhesion molecule that supports ß-cells. Furthermore, we reveal that DSG2 is within the top 10 percent of all genes expressed by human pancreatic islets and is expressed by the insulin-producing ß-cells but not the somatostatin-producing δ-cells. In a Dsg2 loss-of-function mice (Dsg2lo/lo), we observed a significant reduction in the number of pancreatic islets and islet size, and consequently, there was less total insulin content per islet cluster. Dsg2lo/lo mice also exhibited a reduction in blood vessel barrier integrity, an increased incidence of streptozotocin-induced diabetes, and islets isolated from Dsg2lo/lo mice were more susceptible to cytokine-induced ß-cell apoptosis. Following transplantation into diabetic mice, islets isolated from Dsg2lo/lo mice were less effective than their wildtype counterparts at curing diabetes. In vitro assays using the Beta-TC-6 murine ß-cell line suggest that DSG2 supports the actin cytoskeleton as well as the release of cytokines and chemokines. Taken together, our study suggests that DSG2 is an under-appreciated regulator of ß-cell function in pancreatic islets and that a better understanding of this adhesion molecule may provide new opportunities to combat type 1 diabetes.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Islotes Pancreáticos , Animales , Humanos , Ratones , Supervivencia Celular , Desmogleínas/metabolismo , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Estreptozocina
4.
Int J Mol Sci ; 23(11)2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-35683026

RESUMEN

AppA, the Escherichia coli periplasmic phytase of clade 2 of the histidine phosphatase (HP2) family, has been well-characterized and successfully engineered for use as an animal feed supplement. AppA is a 1D-6-phytase and highly stereospecific but transiently accumulates 1D-myo-Ins(2,3,4,5)P4 and other lower phosphorylated intermediates. If this bottleneck in liberation of orthophosphate is to be obviated through protein engineering, an explanation of its rather rigid preference for the initial site and subsequent cleavage of phytic acid is required. To help explain this behaviour, the role of the catalytic proton donor residue in determining AppA stereospecificity was investigated. Four variants were generated by site-directed mutagenesis of the active site HDT amino acid sequence motif containing the catalytic proton donor, D304. The identity and position of the prospective proton donor residue was found to strongly influence stereospecificity. While the wild-type enzyme has a strong preference for 1D-6-phytase activity, a marked reduction in stereospecificity was observed for a D304E variant, while a proton donor-less mutant (D304A) displayed exclusive 1D-1/3-phytase activity. High-resolution X-ray crystal structures of complexes of the mutants with a non-hydrolysable substrate analogue inhibitor point to a crucial role played by D304 in stereospecificity by influencing the size and polarity of specificity pockets A and B. Taken together, these results provide the first evidence for the involvement of the proton donor residue in determining the stereospecificity of HP2 phytases and prepares the ground for structure-informed engineering studies targeting the production of animal feed enzymes capable of the efficient and complete dephosphorylation of dietary phytic acid.


Asunto(s)
6-Fitasa , Proteínas de Escherichia coli , 6-Fitasa/metabolismo , Fosfatasa Ácida/metabolismo , Animales , Fosfatos de Dinucleósidos , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Ácido Fítico/metabolismo , Estudios Prospectivos , Protones
5.
Commun Biol ; 4(1): 1111, 2021 09 22.
Artículo en Inglés | MEDLINE | ID: mdl-34552183

RESUMEN

The growth of solid tumours relies on an ever-increasing supply of oxygen and nutrients that are delivered via vascular networks. Tumour vasculature includes endothelial cell lined angiogenesis and the less common cancer cell lined vasculogenic mimicry (VM). To study and compare the development of vascular networks formed during angiogenesis and VM (represented here by breast cancer and pancreatic cancer cell lines) a number of in vitro assays were utilised. From live cell imaging, we performed a large-scale automated extraction of network parameters and identified properties not previously reported. We show that for both angiogenesis and VM, the characteristic network path length reduces over time; however, only endothelial cells increase network clustering coefficients thus maintaining small-world network properties as they develop. When compared to angiogenesis, the VM network efficiency is improved by decreasing the number of edges and vertices, and also by increasing edge length. Furthermore, our results demonstrate that angiogenic and VM networks appear to display similar properties to road traffic networks and are also subject to the well-known Braess paradox. This quantitative measurement framework opens up new avenues to potentially evaluate the impact of anti-cancer drugs and anti-vascular therapies.


Asunto(s)
Células Endoteliales/patología , Neovascularización Patológica/fisiopatología , Antineoplásicos , Línea Celular Tumoral , Humanos
6.
Sci Rep ; 10(1): 5869, 2020 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-32246008

RESUMEN

Tumour vasculature supports the growth and progression of solid cancers with both angiogenesis (endothelial cell proliferation) and vasculogenic mimicry (VM, the formation of vascular structures by cancer cells themselves) predictors of poor patient outcomes. Increased circulating platelet counts also predict poor outcome for cancer patients but the influence of platelets on tumour vasculature is incompletely understood. Herein, we show with in vitro assays that platelets did not influence angiogenesis but did actively inhibit VM formation by cancer cell lines. Both platelet sized beads and the releasates from platelets were partially effective at inhibiting VM formation suggesting that direct contact maximises the effect. Platelets also promoted cancer cell invasion in vitro. B16F10 melanomas in Bcl-xPlt20/Plt20 thrombocytopenic mice showed a higher content of VM than their wildtype counterparts while angiogenesis did not differ. In a xenograft mouse model of breast cancer with low-dose aspirin to inactivate the platelets, the burden of MDA-MB-231-LM2 breast cancer cells was reduced and the gene expression profile of the cancer cells was altered; but no effect on tumour vasculature was observed. Taken together, this study provides new insights into the action of platelets on VM formation and their involvement in cancer progression.


Asunto(s)
Plaquetas/patología , Neoplasias/irrigación sanguínea , Neovascularización Patológica/patología , Animales , Apoptosis/efectos de los fármacos , Aspirina/uso terapéutico , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Masculino , Melanoma/patología , Ratones , Ratones Endogámicos BALB C , Metástasis de la Neoplasia , Trasplante de Neoplasias , Neoplasias/patología
7.
BMJ Open ; 8(2): e016633, 2018 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-29439065

RESUMEN

BACKGROUND: Humans are by nature a social species, with much of human experience spent in social interaction. Unsurprisingly, social functioning is crucial to well-being and quality of life across the lifespan. While early intervention for social problems appears promising, our ability to identify the specific impairments underlying their social problems (eg, social communication) is restricted by a dearth of accurate, ecologically valid and comprehensive child-direct assessment tools. Current tools are largely limited to parent and teacher ratings scales, which may identify social dysfunction, but not its underlying cause, or adult-based experimental tools, which lack age-appropriate norms. The present study describes the development and standardisation of Paediatric Evaluation of Emotions, Relationships, and Socialisation (PEERS®), an iPad-based social skills assessment tool. METHODS: The PEERS project is a cross-sectional study involving two groups: (1) a normative group, recruited from early childhood, primary and secondary schools across metropolitan and regional Victoria, Australia; and (2) a clinical group, ascertained from outpatient services at The Royal Children's Hospital Melbourne (RCH). The project aims to establish normative data for PEERS®, a novel and comprehensive app-delivered child-direct measure of social skills for children and youth. The project involves recruiting and assessing 1000 children aged 4.0-17.11 years. Assessments consist of an intellectual screen, PEERS® subtests, and PEERS-Q, a self-report questionnaire of social skills. Parents and teachers also complete questionnaires relating to participants' social skills. Main analyses will comprise regression-based continuous norming, factor analysis and psychometric analysis of PEERS® and PEERS-Q. ETHICS AND DISSEMINATION: Ethics approval has been obtained through the RCH Human Research Ethics Committee (34046), the Victorian Government Department of Education and Early Childhood Development (002318), and Catholic Education Melbourne (2166). Findings will be disseminated through international conferences and peer-reviewed journals. Following standardisation of PEERS®, the tool will be made commercially available.


Asunto(s)
Emociones , Psicometría/métodos , Habilidades Sociales , Socialización , Encuestas y Cuestionarios , Adolescente , Niño , Desarrollo Infantil , Preescolar , Computadoras de Mano , Estudios Transversales , Intervención Educativa Precoz , Femenino , Humanos , Masculino , Aplicaciones Móviles , Estudios Prospectivos , Calidad de Vida , Proyectos de Investigación , Instituciones Académicas , Victoria
8.
Artículo en Inglés | MEDLINE | ID: mdl-28716883

RESUMEN

The ß common ([ßc]/CD131) family of cytokines comprises granulocyte macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-3, and IL-5, all of which use ßc as their key signaling receptor subunit. This is a prototypic signaling subunit-sharing cytokine family that has unveiled many biological paradigms and structural principles applicable to the IL-2, IL-4, and IL-6 receptor families, all of which also share one or more signaling subunits. Originally identified for their functions in the hematopoietic system, the ßc cytokines are now known to be truly pleiotropic, impacting on multiple cell types, organs, and biological systems, and thereby controlling the balance between health and disease. This review will focus on the emerging biological roles for the ßc cytokines, our progress toward understanding the mechanisms of receptor assembly and signaling, and the application of this knowledge to develop exciting new therapeutic approaches against human disease.


Asunto(s)
Citocinas/clasificación , Citocinas/metabolismo , Citocinas/genética , Regulación de la Expresión Génica/fisiología , Humanos , Inflamación/metabolismo , Sepsis/metabolismo , Transducción de Señal
9.
Pediatrics ; 140(2)2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28771406

RESUMEN

BACKGROUND: The Sport Concussion Assessment Tool version 3 (SCAT3) and its child version (ChildSCAT3) are composite physical and neuropsychological scoring systems used to assess athletes after sport-related concussion. Based on limited validation data, we aimed to evaluate the ability of SCAT3 and ChildSCAT3 to differentiate children aged 5 to 16 years with concussion from controls. METHODS: Prospective observational study of children in the emergency department with concussion (CONC group) and 2 control groups ([1] upper-limb injury [ULI] and [2] Well children) with equal-sized subgroups in 3 age bands of 5 to 8, 9 to 12, and 13 to 16 years. ChildSCAT3 was used for participants aged 5 to 12 years, and SCAT3 was used for participants aged 13 to 16 years. Differences between study groups were analyzed by using analysis of variance models, adjusting for age and sex. RESULTS: We enrolled 264 children (90 CONC, 90 ULI, and 84 Well) in equal-sized age bands. The number and severity of child- and parent-reported symptom scores were significantly higher in the CONC group than either control group (P < .001). Mean double (ChildSCAT3 P < .001) and tandem stance errors (both P ≤ .01) were also significantly higher, and immediate memory was significantly lower for the CONC group (P < .01). No statistically significant group differences were found for orientation and digit backward tasks. There were no significant differences between ULI and Well control groups. CONCLUSIONS: Overall, SCAT3 and ChildSCAT3 can differentiate concussed from nonconcussed patients, particularly in symptom number and severity.


Asunto(s)
Traumatismos en Atletas/diagnóstico , Conmoción Encefálica/diagnóstico , Examen Neurológico/estadística & datos numéricos , Pruebas Neuropsicológicas/estadística & datos numéricos , Psicometría/estadística & datos numéricos , Adolescente , Estudios de Casos y Controles , Niño , Preescolar , Servicio de Urgencia en Hospital , Femenino , Humanos , Masculino , Estudios Prospectivos , Curva ROC , Reproducibilidad de los Resultados , Autoinforme , Victoria
10.
J Trauma Stress ; 30(3): 237-244, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28644537

RESUMEN

This study investigated factors associated with acute stress symptoms in parents of seriously ill children across a range of illnesses and treatment settings within a pediatric hospital setting. It was hypothesized that psychosocial variables would be more strongly associated with acute stress responses than demographic and child illness variables. Participants were 115 mothers and 56 fathers of children treated within the oncology, cardiology, and intensive care departments of a pediatric hospital. Acute stress, psychosocial, demographic, and medical data were collected within the first 4 weeks of the child's hospital admission. A robust hierarchical regression model revealed that psychosocial factors significantly explained 36.8% of the variance in parent acute stress responses (p < .001); demographic variables significantly added a further 4.5% (p = .022), but illness-related factors did not contribute to the model. Findings support the implementation of a general psychosocial screening approach for parents across the wider hospital system, and that psychosocial risk factors may be targeted in interventions across different illnesses and treatment settings to improve parent outcomes.


Asunto(s)
Padres/psicología , Trastornos de Estrés Traumático Agudo/epidemiología , Adolescente , Adulto , Ansiedad/epidemiología , Niño , Preescolar , Enfermedad Crítica/psicología , Estudios Transversales , Depresión/epidemiología , Femenino , Humanos , Lactante , Unidades de Cuidado Intensivo Pediátrico/estadística & datos numéricos , Estudios Longitudinales , Masculino , Factores de Riesgo , Trastornos de Estrés Traumático Agudo/prevención & control
11.
Health Psychol ; 36(8): 779-786, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28530432

RESUMEN

OBJECTIVE: Posttraumatic stress disorder (PTSD) and posttraumatic stress symptoms (PTSSs) are common for parents of children with life-threatening illnesses or injuries. The impact of these psychological sequelae on parents' personal use of health services is unknown. The present study aimed to investigate whether PTSS severity prospectively predicts increased health service utilization (HSU), and to examine the relative importance of other predisposing and enabling factors in predicting HSU. METHOD: The sample comprised 106 parents of children with various life threatening illnesses, who completed a resource use questionnaire at 19 months following their child's diagnosis or admission. HSU was assessed as reported general practitioner and psychologist visits. RESULTS: Parent PTSS severity at 7 months following their child's diagnosis or hospital admission predicted being in higher service utilization categories in the following 12 months; as PTSS score increased, the odds of being in higher categories increased. Hierarchical ordinal logistic regression procedures indicated predisposing and enabling factors failed to further explain HSU. CONCLUSIONS: These findings highlight the importance of PTSSs to HSU and are consistent with studies of samples experiencing other forms of trauma, such as war or natural disaster. Our results also suggest that an individuals' need, in terms of the severity of their PTSSs, appears most important in predicting their health service engagement. Although this is positive, the effectiveness of this service use, in terms of cost and outcomes, remains unclear. Further, despite the levels of PTSSs observed in the present sample, a minority of individuals sought psychosocial care. (PsycINFO Database Record


Asunto(s)
Servicios de Salud Mental/estadística & datos numéricos , Padres/psicología , Trastornos por Estrés Postraumático/diagnóstico , Adulto , Niño , Femenino , Humanos , Modelos Logísticos , Masculino , Relaciones Padres-Hijo , Índice de Severidad de la Enfermedad , Trastornos por Estrés Postraumático/psicología , Trastornos por Estrés Postraumático/terapia , Encuestas y Cuestionarios , Resultado del Tratamiento
12.
PLoS One ; 7(11): e46996, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23144795

RESUMEN

Circulating vascular progenitor cells contribute to the pathological vasculogenesis of cancer whilst on the other hand offer much promise in therapeutic revascularization in post-occlusion intervention in cardiovascular disease. However, their characterization has been hampered by the many variables to produce them as well as their described phenotypic and functional heterogeneity. Herein we have isolated, enriched for and then characterized a human umbilical cord blood derived CD133(+) population of non-adherent endothelial forming cells (naEFCs) which expressed the hematopoietic progenitor cell markers (CD133, CD34, CD117, CD90 and CD38) together with mature endothelial cell markers (VEGFR2, CD144 and CD31). These cells also expressed low levels of CD45 but did not express the lymphoid markers (CD3, CD4, CD8) or myeloid markers (CD11b and CD14) which distinguishes them from 'early' endothelial progenitor cells (EPCs). Functional studies demonstrated that these naEFCs (i) bound Ulex europaeus lectin, (ii) demonstrated acetylated-low density lipoprotein uptake, (iii) increased vascular cell adhesion molecule (VCAM-1) surface expression in response to tumor necrosis factor and (iv) in co-culture with mature endothelial cells increased the number of tubes, tubule branching and loops in a 3-dimensional in vitro matrix. More importantly, naEFCs placed in vivo generated new lumen containing vasculature lined by CD144 expressing human endothelial cells (ECs). Extensive genomic and proteomic analyses of the naEFCs showed that intercellular adhesion molecule (ICAM)-3 is expressed on their cell surface but not on mature endothelial cells. Furthermore, functional analysis demonstrated that ICAM-3 mediated the rolling and adhesive events of the naEFCs under shear stress. We suggest that the distinct population of naEFCs identified and characterized here represents a new valuable therapeutic target to control aberrant vasculogenesis.


Asunto(s)
Antígenos CD/análisis , Antígenos CD/metabolismo , Moléculas de Adhesión Celular/análisis , Moléculas de Adhesión Celular/metabolismo , Células Endoteliales/citología , Sangre Fetal/citología , Células Madre/citología , Antígeno AC133 , Antígenos CD/genética , Adhesión Celular , Moléculas de Adhesión Celular/genética , Diferenciación Celular , Separación Celular , Células Cultivadas , Células Endoteliales/metabolismo , Femenino , Glicoproteínas/análisis , Células Endoteliales de la Vena Umbilical Humana/citología , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Péptidos/análisis , Embarazo , ARN Mensajero/genética , Células Madre/metabolismo , Estrés Mecánico , Regulación hacia Arriba
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