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1.
Mol Psychiatry ; 26(7): 3572-3585, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33867523

RESUMEN

Among the genetic factors playing a key role in the etiology of intellectual disabilities (IDs) and autism spectrum disorders (ASDs), several encode RNA-binding proteins (RBPs). In this study, we deciphered the molecular and cellular bases of ID-ASD in a patient followed from birth to the age of 21, in whom we identified a de novo CSDE1 (Cold Shock Domain-containing E1) nonsense variation. CSDE1 encodes an RBP that regulates multiple cellular pathways by monitoring the translation and abundance of target transcripts. Analyses performed on the patient's primary fibroblasts showed that the identified CSDE1 variation leads to haploinsufficiency. We identified through RNA-seq assays the Wnt/ß-catenin signaling and cellular adhesion as two major deregulated pathways. These results were further confirmed by functional studies involving Wnt-specific luciferase and substrate adhesion assays. Additional data support a disease model involving APC Down-Regulated-1 (APCDD1) and cadherin-2 (CDH2), two components of the Wnt/ß-catenin pathway, CDH2 being also pivotal for cellular adhesion. Our study, which relies on both the deep phenotyping and long-term follow-up of a patient with CSDE1 haploinsufficiency and on ex vivo studies, sheds new light on the CSDE1-dependent deregulated pathways in ID-ASD.


Asunto(s)
Trastorno del Espectro Autista , Proteínas de Unión al ADN , Discapacidad Intelectual , Proteínas de Unión al ARN , Vía de Señalización Wnt , Adolescente , Trastorno del Espectro Autista/genética , Adhesión Celular/genética , Niño , Preescolar , Proteínas de Unión al ADN/genética , Humanos , Lactante , Recién Nacido , Discapacidad Intelectual/genética , Proteínas de Unión al ARN/genética , Adulto Joven , beta Catenina/genética
2.
J Eur Acad Dermatol Venereol ; 36(12): 2343-2351, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35881110

RESUMEN

BACKGROUND: Kaposi sarcoma (KS) is a rare skin tumour caused by herpesvirus 8 infection and characterized by either indolence or an aggressive course necessitating systemic therapies. The genetic basis of this difference remains unknown. OBJECTIVES: To explore the tumour mutational burden in indolent and aggressive KS. METHODS: We performed whole-exome sequencing on a cohort of 21 KS patients. We compared genetic landscape including tumor mutational burden between the two forms of indolent and agressive KS. RESULTS: Aggressive KS tumours had a significantly higher TMB and a larger cumulative number of deleterious mutations than indolent KS tumours. In addition, all aggressive tumours had at least three deleterious mutations, whereas most indolent tumours harboured only one or no predicted deleterious mutations. Deleterious mutations listed in the Cancer Gene Census were detected exclusively in patients with aggressive disease. An analysis of somatic copy-number alterations (SCNA) revealed a tendency towards higher number of alterations in aggressive KS. CONCLUSIONS: These data suggest that SCNA alterations and an increase in mutational burden promote aggressive KS and that it might be more appropriate to consider indolent KS as an opportunistic skin disease rather than a cancer.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Herpesvirus Humano 8 , Sarcoma de Kaposi , Neoplasias Cutáneas , Humanos , Sarcoma de Kaposi/patología , Herpesvirus Humano 8/genética , Neoplasias Cutáneas/genética , Mutación
3.
Biochem Biophys Res Commun ; 569: 23-28, 2021 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-34216994

RESUMEN

Intravenous injections of human hematopoietic stem cells (hHSCs) is routinely used in clinic and for modeling hematopoiesis in mice. However, unspecific dilution in vascular system and non-hematopoietic organs challenges engraftment efficiency. Although spleen is capable of extra medullar hematopoiesis, its ability to support human HSC transplantation has never been evaluated. We demonstrate that intra-splenic injection results in high and sustained engraftment of hHSCs into immune-deficient mice, with higher chimerisms than with intravenous or intra-femoral injections. Our results support that spleen microenvironment provides a niche for HSCs amplification and offers a new route for efficient HSC transplantation.


Asunto(s)
Supervivencia de Injerto/fisiología , Trasplante de Células Madre Hematopoyéticas/métodos , Células Madre Hematopoyéticas/citología , Bazo/citología , Animales , Antígenos CD34/metabolismo , Femenino , Citometría de Flujo/métodos , Hematopoyesis/fisiología , Células Madre Hematopoyéticas/metabolismo , Humanos , Inyecciones , Luciferasas/genética , Luciferasas/metabolismo , Mediciones Luminiscentes/métodos , Ratones Endogámicos NOD , Ratones Noqueados , Ratones SCID , Bazo/metabolismo , Quimera por Trasplante , Trasplante Heterólogo
4.
J Clin Microbiol ; 59(2)2021 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-33177120

RESUMEN

We evaluated the utility of the commercial Allplex genital ulcer real-time PCR multiplex assay for detecting Treponema pallidum, herpes simplex virus 1 (HSV-1) and 2 (HSV-2), and Chlamydia trachomatis serovar L (lymphogranuloma venereum [LGV]) DNA in mucosal and genital ulcers in the context of suspected syphilis. In total, 374 documented genital and mucosal ulcers from patients with and without syphilis presenting at several sexually transmitted infection (STI) centers in France from October 2010 to December 2016 were analyzed at the National Reference Center (CNR) for Bacterial STIs at Cochin Hospital in Paris. T. pallidum subsp. pallidum detection results were compared with the final diagnosis based on a combination of clinical examination, serological results, and in-house nested PCR (nPCR). Detections of HSV and LGV were validated against reference methods. We found that 44.6% of the 374 samples tested were positive for T. pallidum subsp. pallidum, 21% for HSV, and 0.8% for LGV. No positive results were obtained for 30.7% of samples, and 4.8% presented coinfections. For T. pallidum subsp. pallidum detection, the overall sensitivity was 80% (95% confidence interval [CI], 76.1 to 84.1%), specificity was 98.8% (95% CI, 97.7 to 99.9%), positive predictive value was 98.8% (95% CI, 97.7 to 99.9%) and negative predictive value was 80.2% (95% CI, 76.2 to 84.2%), with a rate of concordance with the reference method of 92.5% (k = 0.85). This PCR multiplex assay is suitable for T. pallidum subsp. pallidum detection in routine use and facilitates the simultaneous rapid detection of a broad panel of pathogens relevant in a context of suspected syphilis lesions.


Asunto(s)
Sífilis , Treponema pallidum , Francia , Humanos , Reacción en Cadena de la Polimerasa Multiplex , Paris , Sífilis/diagnóstico , Treponema pallidum/genética , Úlcera
5.
Ann Dermatol Venereol ; 148(3): 165-167, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33608114

RESUMEN

OBJECTIVE: Since the beginning of the 21st century, Reunion Island has experienced a syphilis epidemic. Infected patients are mostly heterosexual, with a high proportion of women, suggesting that congenital syphilis is present on the island. To determine whether azithromycin can be used for mass treatment of syphilis on Reunion Island, we assessed the prevalence of macrolide resistance in Treponema pallidum (TP). METHODS: This monocentric cross-sectional study was conducted at the Reunion Island University Hospital. Samples were collected from lesions suggestive of primary or secondary syphilis. Samples positive for TP by multiplex polymerase chain reaction (PCR) were sent to the French National Reference Centre (NRC) for further analysis. Nested PCR-tpp47 was performed on these samples for detection of TP-DNA; 23s rRNA was amplified by PCR in confirmed positive samples. The Restriction Fragment Length Polymorphism (RFLP) technique was performed on samples with amplified 23s rRNA for detection of the A2058G mutation. RESULTS: A total of 129 samples were collected from 119 patients. Of these, 18 tested positive for TP using multiplex PCR and were sent to the NRC. Fifteen (83.3%) of the 18 samples were confirmed positive by nested PCR-tpp47, and 23s rRNA was amplified in only 7 (38.9%) samples. Azithromycin resistance was detected in all TP strains with amplified 23s rRNA. CONCLUSION: Amplification of 23s rRNA was successful in only 7 TP strains, all of which displayed resistance to macrolides. Keeping in mind the small sample size of our study, this suggests that azithromycin should not be used for mass treatment of syphilis in Reunion Island.


Asunto(s)
Sífilis , Treponema pallidum , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Azitromicina/uso terapéutico , Estudios Transversales , Farmacorresistencia Bacteriana/genética , Femenino , Humanos , Macrólidos , Reunión/epidemiología , Sífilis/tratamiento farmacológico , Sífilis/epidemiología , Treponema pallidum/genética
6.
Ann Dermatol Venereol ; 147(2): 127-130, 2020 Feb.
Artículo en Francés | MEDLINE | ID: mdl-31955971

RESUMEN

INTRODUCTION: Syphilis mainly affects men who have sex with men (MSM) between the ages of 20 and 49. Herein we report a case in a teenager illustrating extension of the epidemic to other populations. PATIENTS AND METHODS: A 15-year-old boy consulted in May 2018 for an anal fissure and painful oral erosions. He reported having had unprotected anal sex with another male teenager of the same age three months earlier. Syphilis serology was positive, with a positive treponemal test (TT) and non-treponemal test (VDRL) at 1/128. A treponemal bacterial DNA PCR assay was also positive for swabs obtained from the oral erosions and anal fissure. Due to a history of allergy to penicillin the patient was treated with doxycycline 200mg daily for 14 days. One month later, the mucosal lesions had subsided, and 3 months later the VDRL titer had decreased by 2 dilutions. CONCLUSION: This case of "early" syphilis illustrates a change in the French epidemiology of sexually transmitted diseases (STIs). STIs currently affect very young and previously unexposed metropolitan French populations. These infections are increasing in teenagers due to an increase in high-risk sexual behavior associated with a lack of knowledge of STIs. This case is a reminder of the current decline in the level of knowledge about STIs among teenagers as compared to young people of the same age in the 1990s.


Asunto(s)
Minorías Sexuales y de Género , Sífilis/transmisión , Adolescente , Factores de Edad , Antibacterianos/uso terapéutico , Doxiciclina/uso terapéutico , Fisura Anal/diagnóstico , Fisura Anal/tratamiento farmacológico , Humanos , Masculino , Enfermedades de la Boca/diagnóstico , Enfermedades de la Boca/tratamiento farmacológico , Conducta Sexual , Sífilis/diagnóstico , Sífilis/tratamiento farmacológico , Serodiagnóstico de la Sífilis
8.
Ann Dermatol Venereol ; 146(11): 696-703, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31558291

RESUMEN

Congenital syphilis (CS) is caused by Treponema pallidum infection in utero. There is a need to develop new tools to diagnose CS: the diagnostic value of PCR is difficult to assess. The aim of this study was to describe the clinical and laboratory characteristics of mothers and infants with CS as diagnosed by PCR tests on various maternal and neonatal samples. PATIENTS AND METHODS: We included all infants epidemiologically linked to a mother diagnosed with syphilis whose samples were referred to the Syphilis Reference Center, and for whom at least one positive PCR result was obtained. RESULTS: Twenty-two mother-infant pairs (8.3%) with assay performed on samples from one to four different anatomic sites were included between February 2011 and April 2018. Seven mothers (31.8%) were born abroad, fifteen (68.2%) presented psychological and/or social problems, eight (36.4%) had not been screened for syphilis prior to delivery, and eleven (50%) were referred from French overseas departments or territories, or from the Paris region. Six infants (27.3%) were stillborn and six were born preterm, while fifteen infants (68.2%) presented clinical features of CS. All infants born preterm were symptomatic. Infant VDRL/RPR titer was no greater than four times that in the mother's serum, except in two cases. DISCUSSION: Lack of antenatal care, social disadvantage and psychological issues were common. There is a need for enhanced surveillance both in the French overseas departments/territories and in the Paris region. A larger study is required to assess the sensitivity and specificity of PCR. The best site for sampling has yet to be established. We recommend the collection of as many samples as possible to avoid underdiagnosis of CS.


Asunto(s)
ADN Bacteriano , Reacción en Cadena de la Polimerasa , Sífilis Congénita/diagnóstico , Treponema pallidum/genética , Adolescente , Adulto , Femenino , Francia , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Embarazo , Estudios Prospectivos , Mortinato , Adulto Joven
9.
World J Urol ; 34(7): 917-23, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26498138

RESUMEN

PURPOSE: We evaluated the current indications and surgical and survival outcomes for cryoablation (CA) using either a percutaneous (PCA) or a laparoscopic approach (LCA). We also investigated the ability of the PADUA score to predict the risk of complications and local recurrence. METHODS: A retrospective analysis was performed at two European tertiary referral centers. Parameters analyzed included size, location, approach, operative time, hospital stay, complications, and functional and oncologic outcomes. Univariate and multivariate analyses were performed. An ROC analysis was conducted to evaluate the accuracy of the PADUA score. RESULTS: Eighty patients were included. Mean tumor size was 2.6 cm. PCA was more often performed in posterior (95 vs. 60 %), inferior (72 vs. 32 %), and lateral (87 vs. 55 %) tumors. The global complication rate was 8.75 %, although proximity to the renal sinus resulted in a higher rate (30 vs. 4 %). Mean follow-up was 34 and 23 months for LCA and PCA, respectively. The 5-year recurrence-free survival was 76 and 90 % for LCA and PCA, respectively. Multivariate analysis showed that tumor involvement of the collecting system was predictive of recurrence. Under ROC analysis, PADUA score was a mild predictor for complications (AUC = 0.601) and a good predictor for recurrence (AUC = 0.723); PADUA ≥8 was identified as a cutoff for patients to a higher risk of recurrence. CONCLUSIONS: The percutaneous approach is confirmed to be the preferred CA technique for posterior and lateral tumors. CA in deeper renal lesions and tumors with PADUA score ≥8 might entail a higher risk of recurrence, and closer follow-up should be considered in these patients.


Asunto(s)
Carcinoma de Células Renales/cirugía , Criocirugía/métodos , Criocirugía/tendencias , Neoplasias Renales/cirugía , Anciano , Carcinoma de Células Renales/epidemiología , Femenino , Humanos , Neoplasias Renales/epidemiología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Estudios Retrospectivos , Medición de Riesgo
11.
J Clin Microbiol ; 50(3): 546-52, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22219306

RESUMEN

Syphilis diagnosis is based on clinical observation, serological analysis, and dark-field microscopy (DFM) detection of Treponema pallidum subsp. pallidum, the etiological agent of syphilis, in skin ulcers. We performed a nested PCR (nPCR) assay specifically amplifying the tpp47 gene of T. pallidum from swab and blood specimens. We studied a cohort of 294 patients with suspected syphilis and 35 healthy volunteers. Eighty-seven of the 294 patients had primary syphilis, 103 had secondary syphilis, 40 had latent syphilis, and 64 were found not to have syphilis. The T. pallidum nPCR results for swab specimens were highly concordant with syphilis diagnosis, with a sensitivity of 82% and a specificity of 95%. Reasonable agreement was observed between the results obtained with the nPCR and DFM methods (kappa = 0.53). No agreement was found between the nPCR detection of T. pallidum in blood and the diagnosis of syphilis, with sensitivities of 29, 18, 14.7, and 24% and specificities of 96, 92, 93, and 97% for peripheral blood mononuclear cell (PBMC), plasma, serum, and whole-blood fractions, respectively. HIV status did not affect the frequency of T. pallidum detection in any of the specimens tested. Swab specimens from mucosal or skin lesions seemed to be more useful than blood for the efficient detection of the T. pallidum genome and, thus, for the diagnosis of syphilis.


Asunto(s)
Técnicas Bacteriológicas/métodos , Técnicas de Laboratorio Clínico/métodos , Técnicas de Diagnóstico Molecular/métodos , Reacción en Cadena de la Polimerasa/métodos , Sífilis/diagnóstico , Treponema pallidum/aislamiento & purificación , Adulto , Sangre/microbiología , Proteínas Portadoras/genética , Estudios de Cohortes , Femenino , Humanos , Lipoproteínas/genética , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad , Úlcera Cutánea/microbiología , Treponema pallidum/genética
13.
J Adv Res ; 28: 77-85, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33364047

RESUMEN

INTRODUCTION: Inflammatory Breast Cancer (IBC) is the most aggressive form of breast carcinoma characterized by rapid onset of inflammatory signs and its molecular fingerprint has not yet been elucidated. OBJECTIVES: The objective of this study was to detect both gene expression levels and alternate RNA splice variants specific for IBC. METHODS: W e performed splice-sensitive array profiling using Affymetrix Exon Array and quantitative RT-PCR analyses in 177 IBC compared to 183 non-IBC. We also assessed the prognostic value of the identified candidate genes and splice variants. RESULTS: A 5-splice signature (HSPA8, RPL10, RPL4, DIDO1 and EVL) was able to distinguish IBC from non-IBC tumors (p<10-7). This splice signature was associated with poor metastasis-free survival in hormone receptor-negative non-IBC (p=0.02), but had no prognostic value in IBC. PAM analysis of dysregulated genes in IBC compared to non-IBC identified a 10-gene signature highly predictive of IBC phenotype and conferring a poor prognosis in non-IBC. The genes most commonly upregulated in IBC were 3 hemoglobin genes able to reliably discriminate IBC from non-IBC (p<10-4). Hb protein expression in epithelial breast tumor cells was confirmed by immunohistochemistry. CONCLUSION: IBC has a specific spliced transcript profile and is characterized by hemoglobin gene overexpression that should be investigated in further functional studies.

14.
Dermatology ; 221(3): 201-5, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20720390

RESUMEN

BACKGROUND: Anti-tumor necrosis factor (TNF) agents are increasingly being used for a rapidly expanding number of rheumatic and systemic diseases. As a result of this use, and of the longer follow-up periods of treatment, there are a growing number of reports of the development of autoimmune processes related to anti-TNF agents. The use of anti-TNF agents has been associated with more and more cases of autoimmune diseases, principally cutaneous vasculitis, lupus-like syndrome, systemic lupus erythematosus and interstitial lung disease. OBSERVATIONS: We report 2 cases of autoimmune bullous skin disease occurring in patients undergoing TNF-targeted therapy: a bullous pemphigoid and a pemphigus foliaceus. Both patients were treated by anti-TNF agents for rheumatoid arthritis and showed improvement following interruption of that treatment. Here, we discuss the relationship between anti-TNF therapy and the occurrence of autoimmune bullous disease. CONCLUSION: Anti-TNF agents should be considered as a potential cause of drug-induced autoimmune bullous skin disease.


Asunto(s)
Anticuerpos Monoclonales/efectos adversos , Antirreumáticos/efectos adversos , Penfigoide Ampolloso/inducido químicamente , Pénfigo/inducido químicamente , Inhibidores del Factor de Necrosis Tumoral , Adalimumab , Anciano , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Autoanticuerpos/sangre , Erupciones por Medicamentos/etiología , Femenino , Humanos , Infliximab , Masculino , Persona de Mediana Edad , Penfigoide Ampolloso/diagnóstico , Pénfigo/diagnóstico
15.
Ann R Coll Surg Engl ; 101(6): e136-e138, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31155895

RESUMEN

Completely endophytic renal tumours pose challenges in laparoscopic nephron-sparing tumour excisions, with the use of intraoperative imaging techniques (e.g. ultrasound) being crucial when managing such tumours. The use of a percutaneous hookwire for tumour localisations are in use in several other surgical fields, such as breast surgery. An asymptomatic 52-year-old man presented with an incidental small right sided solid 33-mm interpolar renal mass identified on computed tomography. A guided insertion of a percutaneous localisation wire was carried out prior to a laparoscopic partial nephrectomy to assist in intraoperative tumour landmark/margins identification. Operative time was 210 minutes with zero ischaemia time, with an estimated blood loss of 200 ml. No perioperative complications were observed and the patient was discharged two days postoperatively. Histology revealed the mass to be a Fuhrman grade 2 clear-cell carcinoma with a 2-mm clear surgical margin. The patient remained free of recurrence at 16 months of follow-up. We have reported our first experience of wire localisation prior to laparoscopic partial nephrectomy for an intrarenal mass, which to our knowledge could be the first of its kind in renal surgery. Percutaneous wire localisation of endophytic renal tumours is potentially safe and effective and can allow nephron-sparing surgery where laparoscopic ultrasound is not available. Longer-term and further evidence should be encouraged.


Asunto(s)
Carcinoma de Células Renales/cirugía , Neoplasias Renales/cirugía , Laparoscopía/métodos , Instrumentos Quirúrgicos , Carcinoma de Células Renales/diagnóstico por imagen , Humanos , Neoplasias Renales/diagnóstico por imagen , Laparoscopía/instrumentación , Masculino , Persona de Mediana Edad , Nefrectomía/instrumentación , Nefrectomía/métodos , Radiografía Intervencional/instrumentación , Radiografía Intervencional/métodos , Tomografía Computarizada por Rayos X
16.
Transfus Clin Biol ; 26(4): 316-323, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30391125

RESUMEN

OBJECTIVES: The first-passage adherent human bone marrow fibroblast-like cell population corresponds, in terms of phenotype and three-lineage differentiation capacity (assayed in bulk culture), to commonly termed "mesenchymal stem cells". Here we determine the proportion of high proliferative capacity multipotent cells present in this population in order to estimate the proportion of cells that can or cannot be considered as stem and progenitor cells. MATERIAL AND METHODS: The single-cell cultures were established starting from human bone marrow-derived first-passage fibroblast-like cells and the proliferating clones were either transferred to secondary cultures to evaluate their further clonogenicity, or split into three wells to assess differentiation into each of the three different lineages. RESULTS: The analysis of 197 single-cell cultures from three different bone marrow donors shows that only∼40% of so-called "mesenchymal stem cells" exhibit multipotency and are capable of sustained clonogenicity in secondary cultures. CONCLUSION: Even in the first ex vivo passage under favorable conditions the majority (∼60%) of so-called "mesenchymal stem cells" are not multipotent and thus do not represent a stem cell entity.


Asunto(s)
Células Madre Mesenquimatosas/citología , Antígenos CD/análisis , Células de la Médula Ósea/clasificación , Adhesión Celular , División Celular , Linaje de la Célula , Autorrenovación de las Células , Separación Celular , Células Cultivadas , Células Clonales/citología , Ensayo de Unidades Formadoras de Colonias , Factor 2 de Crecimiento de Fibroblastos/farmacología , Humanos , Análisis de la Célula Individual , Células del Estroma/citología
17.
Oncogene ; 36(17): 2355-2365, 2017 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-27775073

RESUMEN

Triple-negative breast cancer is a heterogeneous disease characterized by the expression of basal cell markers, no estrogen or progesterone receptor expression and a lack of HER2 overexpression. Triple-negative tumors often display activated Wnt/ß-catenin signaling and most have impaired p53 function. We studied the interplay between p53 loss and Wnt/ß-catenin signaling in stem cell function and tumorigenesis, by deleting p53 from the mammary epithelium of K5ΔNßcat mice displaying a constitutive activation of Wnt/ß-catenin signaling in basal cells. K5ΔNßcat transgenic mice present amplification of the basal stem cell pool and develop triple-negative mammary carcinomas. The loss of p53 in K5ΔNßcat mice led to an early expansion of mammary stem/progenitor cells and accelerated the formation of triple-negative tumors. In particular, p53-deficient tumors expressed high levels of integrins and extracellular matrix components and were enriched in cancer stem cells. They also overexpressed the tyrosine kinase receptor Met, a feature characteristic of human triple-negative breast tumors. The inhibition of Met kinase activity impaired tumorsphere formation, demonstrating the requirement of Met signaling for cancer stem cell growth in this model. Human basal-like breast cancers with predicted mutated p53 status had higher levels of MET expression than tumors with wild-type p53. These results connect p53 loss and ß-catenin activation to stem cell regulation and tumorigenesis in triple-negative cancer and highlight the role of Met signaling in maintaining cancer stem cell properties, revealing new cues for targeted therapies.


Asunto(s)
Células Madre Neoplásicas/patología , Neoplasias de la Mama Triple Negativas/patología , Proteína p53 Supresora de Tumor/deficiencia , Animales , Modelos Animales de Enfermedad , Matriz Extracelular/metabolismo , Femenino , Eliminación de Gen , Ratones , Proteínas Proto-Oncogénicas c-met/metabolismo , Transducción de Señal , Neoplasias de la Mama Triple Negativas/genética , Proteína p53 Supresora de Tumor/genética , beta Catenina/metabolismo
18.
Vet Res Commun ; 30(1): 57-71, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16362611

RESUMEN

Many strains of enterotoxigenic Escherichia coli (ETEC) that cause diarrhoea in young piglets secrete a heat-labile enterotoxin (LTp) that binds to specific glycoconjugates on porcine intestinal epithelial cells. Binding of LTp to an appropriate glycoconjugate facilitates the uptake and trafficking of the toxin into the cell, where it stimulates intracellular changes that promote fluid secretion and diarrhoea. The objective of the current study was to identify the LTp-binding glycoconjugates on porcine intestinal epithelial cells, the natural target cells for LTp. We found that LTp binds, in an age-correlated manner, to an acidic glycosphingolipid (GSL) that co-migrated with GM1 on thin-layer chromatography (TLC), a small acidic GSL that appears to be a sulphatide, a neutral GSL that co-migrated with neolactotetraglycosylceramide (nLc4) on TLC, and two glycoproteins (36 and 205 kDa). Of these potential LTp receptors, the GM1-co-migrating GSL was detected most intensely in young animals, while the other four LTp-binding glycoconjugates were detected most intensely in older pigs (> or= 4 weeks). Since ETEC primarily cause disease in young piglets, the GM1-co-migrating GSL is the most likely candidate for a functional LTp receptor.


Asunto(s)
Toxinas Bacterianas/metabolismo , Enterotoxinas/metabolismo , Infecciones por Escherichia coli/veterinaria , Proteínas de Escherichia coli/metabolismo , Escherichia coli/fisiología , Enfermedades Intestinales/veterinaria , Enfermedades de los Porcinos/microbiología , Factores de Edad , Animales , Animales Recién Nacidos , Electroforesis en Gel de Poliacrilamida/veterinaria , Escherichia coli/crecimiento & desarrollo , Escherichia coli/metabolismo , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/patología , Glicoconjugados/metabolismo , Enfermedades Intestinales/microbiología , Enfermedades Intestinales/patología , Microvellosidades/microbiología , Ácido Peryódico/farmacología , Porcinos , Enfermedades de los Porcinos/patología
19.
Adv Exp Med Biol ; 412: 357-61, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9192041

RESUMEN

Enteropathogenic K88 fimbricated E. coli colonize the piglet small intestine. In swine, it has been previously established that some pigs lack intestinal receptors for K88 lectins and that these animals are resistant to infections by K88-positive E. coli. The receptor is inherited as a simple mendelian character. The interactions established between the glycoconjugate receptors of pig brush borders and K88 lectins are mediated by O- and N-linked glycoproteins which differ between adhesive and non-adhesive piglets. In this study the adhesion of E. coli K88+ in crossbred F2 (LW x MS) x (LW x MS) populations. By using in vitro brush border test, we observed modulation of the adhesion of K88 fimbriae and distinguished high and low affinity receptors. Furthermore, we correlated the attachment with glycoprotein pattern of epithelial cells and mucus. Epithelial cells and mucus contained several glycopeptides (from 42 to 74 kDa) recognized by K88ab fimbriae. The 74 kDa glycoprotein was characteristic of adhesive phenotype and was a mucosal transferrin (iTf). It appeared that iTf was more abundant in adhesive intestines than in non-adhesive ones, suggesting that susceptibility/resistance phenotype could be related to iron metabolism in the intestinal tract. Furthermore, we visualized the intestinal transferrin receptors on the brush border membrane of epithelial cells, probably implicated in iron absorption.


Asunto(s)
Antígenos Bacterianos , Antígenos de Superficie/genética , Proteínas de Escherichia coli , Escherichia coli/genética , Proteínas Fimbrias , Intestino Delgado/microbiología , Hierro/metabolismo , Animales , Transporte Biológico , Membrana Celular/metabolismo , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/patología , Infecciones por Escherichia coli/veterinaria , Glicoproteínas/metabolismo , Intestino Delgado/metabolismo , Mucinas/metabolismo , Receptores de Transferrina/metabolismo , Porcinos , Transferrina/metabolismo
20.
Adv Exp Med Biol ; 473: 147-54, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10659352

RESUMEN

The three antigenic variants of the K88 fimbrial adhesin (K88ab, K88ac, and K88ad) of enterotoxigenic Escherichia coli (ETEC) each exhibit unique specificity with regard to their hemagglutination characteristics. The variants are also unique in the specificity of their binding to the brush borders of enterocytes isolated from pigs with different genetic backgrounds. Diversity in enterocyte binding specificity suggests the existence of several K88 receptors, expressed individually or in various combinations on porcine enterocytes. Three candidate receptors have been identified that may explain the adhesion of K88 fimbrial variants to various porcine enterocytes. These receptors are an intestinal mucin-type sialoglycoprotein (IMTGP), an intestinal transferrin (GP74), and an intestinal neutral glycosphingolipid (IGLad). The IMTGP binds K88ab and K88ac, but not K88ad. The GP74 binds K88ab, but not K88ac or K88ad, and the IGLad binds K88ad, but not K88ab or K88ac. Each of the candidate receptors has been found in brush borders that are adhesive for the fimbriae that bind the respective receptor. They have not been found in brush borders that are not adhesive for those same fimbriae. The presence of IMTGP was highly correlated with susceptibility of neonatal gnotobiotic pigs to ETEC expressing K88ab or K88ac.


Asunto(s)
Adhesinas de Escherichia coli/metabolismo , Antígenos Bacterianos , Antígenos de Superficie/metabolismo , Proteínas de Escherichia coli , Escherichia coli/metabolismo , Proteínas Fimbrias , Mucosa Intestinal/metabolismo , Receptores de Antígenos/metabolismo , Adhesinas de Escherichia coli/clasificación , Animales , Antígenos de Superficie/clasificación , Escherichia coli/inmunología , Intestinos/microbiología , Fenotipo , Porcinos
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