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1.
Transfusion ; 63(12): 2328-2340, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37942518

RESUMEN

BACKGROUND: Red blood cell wastage occurs when blood is discarded rather than transfused, and ineffective ordering results in unnecessary crossmatch procedures. We describe how a multimodal approach to redesigning electronic ordering tools improved blood utilization in a pediatric inpatient setting and how using innovative application of time series data analysis provides insights into intervention effectiveness, which can guide future process improvement cycles. METHODS: A multidisciplinary team used best practices and Toyota Production System methodology to redesign electronic blood ordering and improve administration processes. We analyzed crossmatch to transfusion ratio and red blood cell wastage time series data extracted from our laboratory information system and electronic health record. We used changepoint analysis to identify statistically discernible breaks in each time series, compatible with known interventions. We performed causal impact analysis on red blood cell wastage time series data to estimate blood wastage avoided due to the interventions. RESULTS: Changepoint analysis estimated an 11% decrease in crossmatch to transfusion ratio and a 77% decrease in red blood cell monthly wastage rate during the intervention period. Causal impact analysis estimated a 61% reduction in expected wastage compared to the scenario if the interventions had not occurred. DISCUSSION: Our results show that electronic health record design is an important factor in reducing waste and preventing unnecessary crossmatching, and that time series analysis can be a useful tool for evaluating the long-term impact of each stage of intervention in a longitudinal process redesign effort for the purpose of effectively targeting future improvement efforts.


Asunto(s)
Transfusión Sanguínea , Hospitales Pediátricos , Humanos , Niño , Flujo de Trabajo , Transfusión Sanguínea/métodos , Tipificación y Pruebas Cruzadas Sanguíneas , Eritrocitos
3.
Br J Anaesth ; 120(4): 629-644, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29576105

RESUMEN

QT prolongation can be attributable to various causes that can be categorised as acquired or congenital. Arrhythmias related to QT prolongation can result in clinical presentations, such as syncope and sudden cardiac death. The perioperative period presents a number of issues that may affect a patient's risk of developing polymorphic ventricular tachycardia or torsades de pointes. Although most patients may have an unremarkable perioperative course, some may have complications; this review article aims to help clinicians avoid potential complications, and to help them address treatment for perioperative issues that may occur.


Asunto(s)
Síndrome de QT Prolongado/cirugía , Atención Perioperativa/métodos , Humanos , Síndrome de QT Prolongado/congénito
4.
Oncogene ; 28(46): 4041-52, 2009 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-19802002

RESUMEN

Neuregulin-1 (NRG1) is both a candidate oncogene and a candidate tumour suppressor gene. It not only encodes the heregulins and other mitogenic ligands for the ERBB family, but also causes apoptosis in NRG1-expressing cells. We found that most breast cancer cell lines had reduced or undetectable expression of NRG1. This included cell lines that had translocation breaks in the gene. Similarly, expression in cancers was generally comparable to or less than that in various normal breast samples. Many non-expressing cell lines had extensive methylation of the CpG island at the principal transcription start site at exon 2 of NRG1. Expression was reactivated by demethylation. Many tumours also showed methylation, whereas normal mammary epithelial fragments had none. Lower NRG1 expression correlated with higher methylation. Small interfering RNA (siRNA)-mediated depletion of NRG1 increased net proliferation in a normal breast cell line and a breast cancer cell line that expressed NRG1. The short arm of chromosome 8 is frequently lost in epithelial cancers, and NRG1 is the most centromeric gene that is always affected. NRG1 may therefore be the major tumour suppressor gene postulated to be on 8p: it is in the correct location, is antiproliferative and is silenced in many breast cancers.


Asunto(s)
Neoplasias de la Mama/genética , Aberraciones Cromosómicas , Cromosomas Humanos Par 8 , Metilación de ADN , Silenciador del Gen , Genes Supresores de Tumor , Neurregulina-1/genética , Secuencia de Bases , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular , Mapeo Cromosómico , Cromosomas Humanos Par 8/química , Cromosomas Humanos Par 8/genética , Islas de CpG/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Predisposición Genética a la Enfermedad/genética , Humanos , Neurregulina-1/fisiología , Sitio de Iniciación de la Transcripción
5.
Kidney Int ; 72(2): 157-65, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17396115

RESUMEN

Autosomal dominant polycystic kidney disease (ADPKD) largely results from mutations in the PKD1 gene leading to hyperproliferation of renal tubular epithelial cells and consequent cyst formation. Rodent models of PKD suggest that the multifunctional hormone insulin-like growth factor-1 (IGF-1) could play a pathogenic role in renal cyst formation. In order to test this possibility, conditionally immortalized renal epithelial cells were prepared from normal individuals and from ADPKD patients with known germline mutations in PKD1. All patient cell lines had a decreased or absence of polycystin-1 but not polycystin-2. These cells had an increased sensitivity to IGF-1 and to cyclic AMP, which required phosphatidylinositol-3 (PI3)-kinase and the mitogen-activated protein kinase, extracellular signal-regulated protein kinase (ERK) for enhanced growth. Inhibition of Ras or Raf abolished the stimulated cell proliferation. Our results suggest that haploinsufficiency of polycystin-1 lowers the activation threshold of the Ras/Raf signalling system leading to growth factor-induced hyperproliferation. Inhibition of Ras or Raf activity may be a therapeutic option for decreasing tubular cell proliferation in ADPKD.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Factor I del Crecimiento Similar a la Insulina/farmacología , Riñón Poliquístico Autosómico Dominante/patología , Canales Catiónicos TRPP , Quinasas raf/efectos de los fármacos , Proteínas Activadoras de ras GTPasa/efectos de los fármacos , Línea Celular , Quistes/patología , Mutación de Línea Germinal , Humanos , Factor I del Crecimiento Similar a la Insulina/fisiología , Túbulos Renales/patología , Riñón Poliquístico Autosómico Dominante/tratamiento farmacológico , Riñón Poliquístico Autosómico Dominante/metabolismo , Transducción de Señal/efectos de los fármacos , Quinasas raf/metabolismo , Proteínas Activadoras de ras GTPasa/metabolismo
6.
J Pathol ; 210(4): 420-30, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17054309

RESUMEN

This study demonstrates, through a combination of stringent screening methods and thorough validation, that it is possible to identify transmembrane proteins preferentially expressed in primary breast tumour cells. mRNA was extracted from tumour cells isolated from invasive breast cancers and it was then subtracted against normal breast tissue mRNA prior to the generation of a signal sequence-trap library. Screening of the library identified 31 positive clones encoding 12 cell-surface and 12 secreted proteins. The expression of a subset of transmembrane genes was then interrogated using a high-throughput method (tissue microarray) coupled with cutting-edge in situ techniques in a large cohort of patients who had undergone uniform adjuvant chemotherapy. Expression of CD98 heavy chain (CD98HC) and low-level expression of the insulin-like growth factor 2 receptor/mannose-6-phosphate receptor (IGF2R/M6PR) correlated with poor patient prognosis in the whole cohort. Expression of bradykinin receptor B1 (BDKRB1) and testis enhanced gene transcript (TEGT) correlated with good prognosis in woman with oestrogen receptor (ER)-negative breast tumours. These results indicate that this combined approach of isolating primary tumour cells, generating a library to specifically isolate signal-sequence-containing transcripts, and in situ hybridization on tissue microarrays successfully identified novel prognostic markers (BDKRB1, CD98hc, and TEGT) and potential transmembrane therapeutic targets (CD98hc) in breast cancer.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias de la Mama/genética , Proteínas de Neoplasias/genética , Transcripción Genética/genética , Proteínas Reguladoras de la Apoptosis , Neoplasias de la Mama/patología , Femenino , Cadena Pesada de la Proteína-1 Reguladora de Fusión/genética , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Hibridación in Situ/métodos , Molécula 1 de Adhesión Intercelular/genética , Proteínas de la Membrana/genética , Invasividad Neoplásica , Pronóstico , Proteínas/genética , ARN Mensajero/genética , ARN Neoplásico/genética , Receptor de Bradiquinina B1/genética , Receptor IGF Tipo 2/genética , Receptores de Estrógenos/genética , Análisis de Matrices Tisulares/métodos
7.
Kidney Int ; 69(9): 1633-40, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16557232

RESUMEN

Glomerular endothelial cells (GEnC) are specialized cells with important roles in physiological filtration and glomerular disease. Despite their unique features, GEnC have been little studied because of difficulty in maintaining them in cell culture. We have addressed this problem by generation of conditionally immortalized (ci) human GEnC using technology with which we have previously produced ci podocytes. Primary culture GEnC were transduced with temperature-sensitive simian virus 40 large tumour antigen and telomerase using retroviral vectors. Cells were selected, cloned, and then characterized by light and electron microscopy (EM), response to vascular endothelial growth factor (VEGF), and tumour necrosis factor (TNF)alpha, expression of endothelial markers by focused gene array, immunofluorescence and Western blotting, and formation and behaviour of monolayers. CiGEnC proliferated at the permissive temperature (33 degrees C) and became growth arrested at the non-permissive temperature (37 degrees C). CiGEnC retained morphological features of early-passage primary culture GEnC up to at least p41, confirming successful immortalization. EM demonstrated fenestrations, increased in number by VEGF. mRNA analysis confirmed expression of the endothelial markers platelet endothelial cell adhesion molecule 1, intercellular adhesion molecule 2, VEGF receptor 2, and von Willebrand factor, validated by immunofluorescence and Western blotting. CiGEnC also expressed Tie2, and TNFalpha upregulated E-selectin. CiGEnC formed monolayers with barrier properties responsive to cyclic adenosine 3',5' monophosphate (cAMP) and thrombin. CiGEnC retain the markers and behaviour of primary culture GEnC. They express fenestrations which are upregulated in response to VEGF. These cells are a unique resource for further study of GEnC and their roles in glomerular filtration, glomerular disease, and response to glomerular injury.


Asunto(s)
Línea Celular Transformada , Células Endoteliales/ultraestructura , Glomérulos Renales/citología , Factor A de Crecimiento Endotelial Vascular/farmacología , Biomarcadores , Moléculas de Adhesión Celular/genética , AMP Cíclico/farmacología , Impedancia Eléctrica , Células Endoteliales/efectos de los fármacos , Células Endoteliales/fisiología , Expresión Génica , Humanos , Glomérulos Renales/efectos de los fármacos , Glomérulos Renales/fisiología , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Mensajero/análisis , ARN Mensajero/metabolismo , Virus 40 de los Simios/genética , Trombina/farmacología , Receptor 2 de Factores de Crecimiento Endotelial Vascular/genética , Factor de von Willebrand/genética
8.
Mol Biol Cell ; 16(2): 943-53, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15574883

RESUMEN

Senescence, the molecular program that limits the finite proliferative potential of a cell, acts as an important barrier to protect the body from cancer. Techniques for measuring transcriptome changes and for modulating their expression suggest that it may be possible to dissect the transcriptional networks underlying complex cellular processes. HMF3A cells are conditionally immortalized human mammary fibroblasts that can be induced to undergo coordinated senescence. Here, we used these cells in conjunction with microarrays, RNA interference, and in silico promoter analysis to promote the dissection of the transcriptional networks responsible for regulating cellular senescence. We first identified changes in the transcriptome when HMF3A cells undergo senescence and then compared them with those observed upon replicative senescence in primary human mammary fibroblasts. In addition to DUSP1 and known p53 and E2F targets, a number of genes such as PHLDA1, NR4A3, and a novel splice variant of STAC were implicated in senescence. Their role in senescence was then analyzed by RNA silencing followed by microarray analysis. In silico promoter analysis of all differential genes predicted that nuclear factor-kappaB and C/EBP transcription factors are activated upon senescence, and we confirmed this by electrophoretic mobility shift assay. The results suggest a putative signaling network for cellular senescence.


Asunto(s)
Senescencia Celular , Senescencia Celular/genética , Fibroblastos/metabolismo , Transcripción Genética , Proteínas de Ciclo Celular/genética , Línea Celular Transformada , Células Cultivadas , Senescencia Celular/fisiología , Medio de Cultivo Libre de Suero , Proteínas de Unión al ADN/genética , Fosfatasa 1 de Especificidad Dual , Ensayo de Cambio de Movilidad Electroforética , Femenino , Regulación de la Expresión Génica , Silenciador del Gen , Humanos , Proteínas Inmediatas-Precoces/genética , Glándulas Mamarias Humanas/citología , Análisis por Micromatrices , Modelos Biológicos , FN-kappa B/metabolismo , Proteínas del Tejido Nervioso/genética , Fosfoproteínas Fosfatasas/genética , Regiones Promotoras Genéticas , Proteína Fosfatasa 1 , Proteínas Tirosina Fosfatasas/genética , Interferencia de ARN , Empalme del ARN , Receptores de Esteroides , Receptores de Hormona Tiroidea , Retroviridae/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteína p53 Supresora de Tumor/genética
9.
J Mol Endocrinol ; 33(1): 35-50, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15291741

RESUMEN

Whilst oestrogen receptor (ER)-alpha and ERbeta have been shown to be important in the development of the mammary gland, the cell-specific expression pattern of these two receptors within the human breast is not clear. Although it is well established that in the developing rodent mammary gland stromal ERalpha mediates the secretion of growth factors which stimulate the proliferation of the ductal epithelium, the expression of ERalpha in human adult breast stromal fibroblasts is controversial, and the expression of ERbeta has not been properly defined. In the present study, we have evaluated the expression of ERalpha and ERbeta by immunohistochemistry in normal tissue samples, and in purified human breast fibroblasts by Western blotting, RT-PCR analysis and ligand-binding sucrose gradient assay. Our data clearly demonstrated that ERbeta variants, including ERbeta1, ERbeta2, ERbeta5, ERbetadelta and ERbetains, but not ERalpha, are expressed in human adult mammary fibroblasts. These results are supported by the findings that an ERbeta-selective ligand, BAG, but not the ERalpha high-affinity ligand oestradiol, can induce fibroblast growth factor-7 release and activate transcription from an oestrogen-responsive element promoter in these adult human mammary fibroblasts. Together, these observations revealed that, in the adult breast and in breast cancer, the proliferative signals derived from the stroma of adult mammary glands in response to oestrogen are not mediated by ERalpha and provide new insights into the nature of stromal-epithelial interactions in the adult mammary gland. In addition, the expression of these ERbeta variants in cells where there is no ERalpha suggested that these ERbeta splice forms may have functions other than that of modulating ERalpha activity.


Asunto(s)
Receptor alfa de Estrógeno/metabolismo , Receptor beta de Estrógeno/metabolismo , Glándulas Mamarias Animales/metabolismo , Animales , Secuencia de Bases , Cartilla de ADN , Receptor alfa de Estrógeno/genética , Receptor beta de Estrógeno/genética , Fibroblastos/metabolismo , Humanos , Inmunohistoquímica , Glándulas Mamarias Animales/citología , Reacción en Cadena de la Polimerasa , ARN Mensajero/genética , ARN Mensajero/metabolismo
10.
Acta Paediatr ; 93(1): 10-6, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14989432

RESUMEN

UNLABELLED: Bile salt-stimulated lipase (BSSL) in human milk exists in multiple molecular forms and it has been shown that approximately one-third of lactating mothers secrete two forms. AIM: to determine the structural features of BSSL that may give rise to this heterogeneity. METHODS: Oligosaccharides present in the proline-rich region in the C-terminus of BSSL were investigated using deglycosylating enzymes and lectin affinity probing to determine the origin of the multiple molecular forms. RESULTS: It was found that the variability in the molecular mass of BSSL is due predominantly to glycosylation. The molecular forms contain similar sugar chains; all forms possess the core disaccharide Galbeta1-3GalNAc and beta-D-galactose, fucose linked at alpha1-6 and sialic acid linkage alpha2-3 to galactose. CONCLUSION: The molecular mass difference in the BSSL molecular forms cannot be attributed to the type of carbohydrate moiety in the sugar chains of the N- and O-linked sites suggesting that the differences arise from the extent or quantity of glycosylation. The oligosaccharides in the C-terminal region contain Lewis x and b and, less prominently, Lewis a antigenic structures. Owing to the presence of these blood-group-related antigenic determinants, the C-terminal region of BSSL may have an adhesive function in cell-cell interactions.


Asunto(s)
Lectinas/metabolismo , Leche Humana/química , Esterol Esterasa/aislamiento & purificación , Electroforesis en Gel de Poliacrilamida , Femenino , Glicosilación , Humanos , Esterol Esterasa/química , Esterol Esterasa/metabolismo
11.
J Endocrinol ; 177(1): 65-81, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12697038

RESUMEN

Keratinocyte growth factor/fibroblast growth factor 7 (KGF/FGF7) is known to be a potent growth factor for mammary cells but its origin, cellular targets and mode of action in the breast are unclear. In this study, we carried out studies to determine the localisation of FGF7 and its receptor, and the related growth factor FGF10. We also determined the factors that regulate FGF7 release from stromal cells and the effects of FGF7 on normal and neoplastic breast cells. Using an FGF7-specific antibody which does not react with the FGF7 heparan sulphate proteoglycan (HSPG)-binding site, we showed epithelial and myoepithelial immunohistochemical staining in normal breast sections, and epithelial staining in breast carcinomas. Stromal staining was also detected in some lobular carcinomas as well as a subset of invasive ductal carcinomas. FGF10 and FGF receptor (FGFR)2 immunostaining showed a similar epithelial expression pattern, whereas no stromal staining was observed. We purified normal breast stromal, epithelial and myoepithelial cells and showed that FGF7 stimulated proliferation of both epithelial cell types, but not stromal fibroblasts. We also examined the effects of FGF7 on Matrigel-embedded organoids, containing both epithelial and myoepithelial cells, and showed FGF7 induced an increase in cellular proliferation. Furthermore, conditioned medium derived from stromal cells was shown to increase the proliferation of normal and neoplastic breast epithelial cells, which could be abolished by a neutralising antibody to FGF7. Finally, we showed that interleukin-1beta, but not oestradiol or other oestrogen receptor ligands, caused a dose-related FGF7 release. Further results also indicate that the epithelial localisation of FGF7 and FGF10 in breast tissue sections is likely to be due to their binding to their cognate receptor. In summary, our findings suggest that FGF7 is a paracrine growth factor in the breast. FGF7 is produced by the breast stromal fibroblasts and has profound proliferative and morphogenic roles on both epithelial and myoepithelial cells.


Asunto(s)
Neoplasias de la Mama/metabolismo , Mama/metabolismo , Factores de Crecimiento de Fibroblastos/análisis , Interleucina-1/farmacología , Comunicación Paracrina/fisiología , Western Blotting/métodos , Neoplasias de la Mama/química , Carcinoma Ductal de Mama/química , Carcinoma Lobular/química , División Celular/efectos de los fármacos , Células Cultivadas , Ensayo de Inmunoadsorción Enzimática/métodos , Células Epiteliales/química , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Femenino , Factor 10 de Crecimiento de Fibroblastos , Factor 7 de Crecimiento de Fibroblastos , Factores de Crecimiento de Fibroblastos/metabolismo , Factores de Crecimiento de Fibroblastos/farmacología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Humanos , Proteínas Tirosina Quinasas Receptoras/análisis , Proteínas Tirosina Quinasas Receptoras/metabolismo , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos , Receptores de Factores de Crecimiento de Fibroblastos/análisis , Receptores de Factores de Crecimiento de Fibroblastos/metabolismo , Células Tumorales Cultivadas
12.
Nat Cell Biol ; 3(9): 823-30, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11533662

RESUMEN

Desmosomes are intercellular junctions of epithelia and are of widespread importance in the maintenance of tissue architecture. We provide evidence that desmosomal adhesion has a function in epithelial morphogenesis and cell-type-specific positioning. Blocking peptides corresponding to the cell adhesion recognition (CAR) sites of desmosomal cadherins block alveolar morphogenesis by epithelial cells from mammary lumen. Desmosomal CAR-site peptides also disrupt positional sorting of luminal and myoepithelial cells in aggregates formed by the reassociation of isolated cells. We demonstrate that desmosomal cadherins and E-cadherin are comparably involved in epithelial morphoregulation. The results indicate a wider role for desmosomal adhesion in morphogenesis than has previously been considered.


Asunto(s)
Cadherinas/fisiología , Adhesión Celular/fisiología , Proteínas del Citoesqueleto/fisiología , Desmosomas/fisiología , Células Epiteliales/citología , Células Epiteliales/fisiología , Animales , Sitios de Unión , Mama/citología , Cadherinas/química , Cadherinas/genética , Bovinos , Agregación Celular , Técnicas de Cultivo de Célula/métodos , Línea Celular , Tamaño de la Célula , Células Cultivadas , Proteínas del Citoesqueleto/química , Desmoplaquinas , Femenino , Regulación de la Expresión Génica , Humanos , Integrinas/análisis , Integrinas/fisiología , Glándulas Mamarias Animales/citología , Ratones , Morfogénesis , Alveolos Pulmonares/citología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transcripción Genética
13.
Cell Tissue Res ; 304(3): 371-6, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11456413

RESUMEN

We have transduced adult human alveolar bone (AB) cells with a gene construct encoding a temperature-sensitive mutation of the SV40 large T antigen (tsT). Such cells divided rapidly, for more than 50 passages thus far, at a permissive low temperature (34.5 degrees C), comparable to the non-transduced parental cells at 37 degrees C. However, the tsT-transduced AB cells failed to grow at a non-permissive high temperature (39 degrees C) at which the T antigen is inactivated. Nevertheless, the cells formed mineralised nodules in vitro at both the low and high temperatures. Flow cytometry analysis showed that the transduced cells cultured at 34.5 degrees C, like the parental cells at 37 degrees C, were smaller and less granular than the transduced cells incubated at 39 degrees C. Moreover, the transduced cells grown at 34.5 degrees C were also found to express bone sialoprotein, osteopontin and type I collagen at levels similar to those of the parental cells at 37 degrees C, although osteonectin and fibronectin were down-regulated. When the transduced cells were incubated at 39 degrees C, the expression of all antigens was up-regulated, particularly osteonectin. Thus, we have obtained long-term cultures of tsT-transduced AB cells whose growth is temperature-dependent and which express certain features characteristic of bone-derived cells.


Asunto(s)
Antígenos Transformadores de Poliomavirus/genética , Transformación Celular Viral , Osteoblastos/citología , Retroviridae/genética , Alveolo Dental/citología , Antígenos Transformadores de Poliomavirus/metabolismo , Biomarcadores/análisis , División Celular , Línea Celular , Tamaño de la Célula , Gránulos Citoplasmáticos/metabolismo , Proteínas de la Matriz Extracelular/inmunología , Proteínas de la Matriz Extracelular/metabolismo , Citometría de Flujo , Calor , Humanos , Cinética , Mutación , Osteoblastos/metabolismo , Sialoglicoproteínas/inmunología , Sialoglicoproteínas/metabolismo , Coloración y Etiquetado , Transducción Genética
16.
Breast Cancer Res ; 3(1): 1-4, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11250738

RESUMEN

The breast myoepithelial cell is the Cinderella of mammary biology. Although its contribution to benign and some malignant pathologies is recognised, it has been largely neglected in molecular and biological studies. The reason for this has been the perception that its role in normal physiology is confined to lactation and the belief that most breast cancers arise from luminal epithelial cells. This review presents our perspective on its broader biological significance and its potential use as a model system for understanding breast carcinogenesis.


Asunto(s)
Neoplasias de la Mama/patología , Mioepitelioma/patología , Neoplasias de la Mama/clasificación , Neoplasias de la Mama/diagnóstico , Femenino , Humanos
17.
Proc Natl Acad Sci U S A ; 98(2): 646-51, 2001 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-11209060

RESUMEN

Reports differ as to whether reconstitution of telomerase activity alone is sufficient for immortalization of different types of human somatic cells or whether additional activities encoded by other "immortalizing" genes are also required. Here we show that ectopic expression of either the catalytic subunit of human telomerase (hTERT) or a temperature-sensitive mutant (U19tsA58) of simian virus 40 large-tumor antigen alone was not sufficient for immortalization of freshly isolated normal adult human mammary fibroblasts and endothelial cells. However, a combination of both genes resulted in the efficient generation of immortal cell lines irrespective of the order in which they were introduced or whether they were introduced early or late in the normal proliferative lifespan of the cultures. The order and timing of transduction, however, did influence genomic stability. Karyotype analysis indicated that introduction of both transgenes at early passage, with hTERT first, yielded diploid cell lines. Temperature-shift experiments revealed that maintenance of the immortalized state depended on continued expression of functional U19tsA58 large-tumor antigen, with hTERT alone unable to maintain growth at nonpermissive temperatures for U19tsA58 large-tumor antigen. Such conditional diploid lines may provide a useful resource for both cell engineering and for studies on immortalization and in vitro transformation.


Asunto(s)
Antígenos Transformadores de Poliomavirus/fisiología , Mama/citología , Endotelio/citología , Fibroblastos/citología , ARN , Telomerasa/fisiología , Adulto , Antígenos Transformadores de Poliomavirus/genética , Dominio Catalítico , División Celular , Línea Celular Transformada , Senescencia Celular , Replicación del ADN , Proteínas de Unión al ADN , Femenino , Vectores Genéticos/genética , Humanos , Cariotipificación , Retroviridae/genética , Virus 40 de los Simios/genética , Telomerasa/genética , Temperatura , Factores de Tiempo , Transfección , Transgenes
18.
J Histochem Cytochem ; 49(2): 271-8, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11156695

RESUMEN

The prostate grows slowly throughout adult life, leading to benign prostatic hyperplasia (BPH), which often results in urethral obstruction in later years. The symptoms of BPH are the second most common reason for surgery in men over 65. The aim of this study was to determine the relationship between cell proliferation and cell differentiation in BPH tissue. Using multiple antibodies, simultaneously detected with different fluorophore-conjugated secondary antibodies, several subpopulations of epithelial cells were detected. In addition to K14, basal cells also expressed keratins 15, 17, and 19 in various combinations, and some of the luminal cells also expressed K19 together with K8 and K18. Co-staining for cytokeratins and Ki-67 indicated that 44% of proliferative cells expressed K14 and 36% K19, although the difference was not statistically significant. This report provides a detailed description of the relationship between keratin expression and cell proliferation in the prostate and indicates that K19-positive cells form the link between the basal and luminal layers of the epithelium. (J Histochem Cytochem 49:271-278, 2001)


Asunto(s)
Células Epiteliales/patología , Queratinas/metabolismo , Próstata/patología , Anciano , Anticuerpos , Compartimento Celular , Diferenciación Celular , División Celular , Células Epiteliales/metabolismo , Humanos , Inmunohistoquímica , Queratinas/inmunología , Masculino , Persona de Mediana Edad , Fenotipo , Hiperplasia Prostática/patología
19.
Cancer Immun ; 1: 4, 2001 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-12747765

RESUMEN

The ability of the immune system to recognize structurally altered, amplified or aberrantly expressed proteins can be used to identify molecules of etiologic relevance to cancer and to define targets for cancer immunotherapy. In the current study, ninety-four distinct antigens reactive with serum IgG from breast cancer patients were identified by immunoscreening breast cancer-derived cDNA expression libraries (SEREX). A serological profile was generated for each antigen on the basis of reactivity with allogeneic sera from normal individuals and cancer patients, and mRNA expression profiles for coding sequences were assembled based upon the tissue distribution of expressed sequence tags, Northern blots and real-time RT-PCR. Forty antigens reacted exclusively with sera from cancer patients. These included well-characterized tumor antigens, e.g. MAGE-3, MAGE-6, NY-ESO-1, Her2neu and p53, as well as newly-defined breast cancer antigens, e.g. kinesin 2, TATA element modulatory factor 1, tumor protein D52 and MAGE D, and novel gene products, e.g. NY-BR-62, NY-BR-75, NY-BR-85, and NY-BR-96. With regard to expression profiles, two of the novel gene products, NY-BR-62 and NY-BR-85, were characterized by a high level of testicular mRNA expression, and were overexpressed in 60% and 90% of breast cancers, respectively. In addition, mRNA encoding tumor protein D52 was overexpressed in 60% of breast cancer specimens, while transcripts encoding SNT-1 signal adaptor protein were downregulated in 70% of these cases. This study adds to the growing list of breast cancer antigens defined by SEREX and to the ultimate objective of identifying the complete repertoire of immunogenic gene products in human cancer (the cancer immunome).


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/inmunología , Formación de Anticuerpos/genética , Formación de Anticuerpos/inmunología , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/inmunología , Neoplasias de la Mama/sangre , ADN Complementario/genética , ADN Complementario/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica/inmunología , Biblioteca de Genes , Humanos , Masculino , ARN Mensajero/genética , ARN Mensajero/metabolismo
20.
Differentiation ; 66(2-3): 106-15, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11100901

RESUMEN

Using multiple immunofluorescence labelling on human breast tissues obtained and freshly frozen at the 12th, 15th, and 18th weeks of pregnancy, we have shown that markers of mammary functional differentiation, milk proteins (beta-casein and kappa-casein), are synthesised by actively cycling (Ki67 positive) as well as non-cycling (Ki67 negative) cells. These results demonstrate that functional differentiation/maturation does not coincide with loss of proliferative potential in human mammary luminal epithelial cells. In addition, we have examined expression patterns of integrin subunits (alpha1, alpha2, alpha3, alpha6, beta1, and beta4) and extracellular matrix components (laminin, fibronectin, collagen I, and collagen IV), since they have been shown to exert influences on mammary differentiation and morphogenesis in vitro. Compared to human breast tissues obtained from non-pregnant women, a decrease in alpha2 labelling on luminal epithelial cells was observed, particularly in expanding acini that showed abundant Ki67 positivity. The expression patterns of other integrin subunits, however, did not change, indicating that the expression patterns of most integrins existing prior to pregnancy are sufficient to support the morphological and functional development associated with milk protein synthesis.


Asunto(s)
Mama/citología , Células Epiteliales/citología , Embarazo/fisiología , Adulto , Mama/fisiología , Caseínas/análisis , Diferenciación Celular , División Celular , Colágeno/análisis , Células Epiteliales/fisiología , Femenino , Fibronectinas/análisis , Técnica del Anticuerpo Fluorescente , Humanos , Integrinas/análisis , Queratinas/análisis , Antígeno Ki-67/análisis , Laminina/análisis , Primer Trimestre del Embarazo , Segundo Trimestre del Embarazo , Vimentina/análisis
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