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1.
Chest ; 159(6): e385-e388, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34099155

RESUMEN

CASE PRESENTATION: A 57-year-old man with a history of polysubstance use presented with shortness of breath, wheezing, productive cough, subjective fever, and chills of 3-day duration. Additionally, he reported worsening shortness of breath for the last 3 months. Of note, the patient was reported to have had, in the previous 6 months, two episodes of pneumonia that was treated with antibiotics and steroids. He was also diagnosed several years prior with adult-onset asthma due to intermittent wheezing and was prescribed an albuterol inhaler. The albuterol did not help relieve his wheezing, and he stopped refilling it.


Asunto(s)
Coagulación con Plasma de Argón/métodos , Biopsia/métodos , Broncoscopía/métodos , Papiloma , Enfermedades de la Tráquea , Estenosis Traqueal , Anciano , Diagnóstico Diferencial , Disnea/diagnóstico , Disnea/etiología , Humanos , Inmunohistoquímica , Masculino , Papiloma/patología , Papiloma/fisiopatología , Ruidos Respiratorios/diagnóstico , Ruidos Respiratorios/etiología , Tomografía Computarizada por Rayos X/métodos , Enfermedades de la Tráquea/patología , Enfermedades de la Tráquea/fisiopatología , Estenosis Traqueal/diagnóstico , Estenosis Traqueal/fisiopatología , Resultado del Tratamiento
2.
Bol. méd. postgrado ; 35(2): 51-56, Jul.-Dec. 2019.
Artículo en Español | LILACS, LIVECS | ID: biblio-1120210

RESUMEN

La papilomatosis respiratoria recurrente (PRR) es la segunda causa más frecuente de disfonía durante la infancia, cuyo agente causal más frecuente es el virus del papiloma humano serotipos 6 y 11. Con el objetivo de analizar las características clínicas y epidemiológicas de la PPR en pacientes pediátricos admitidos en el Servicio Desconcentrado Hospital Pediátrico Dr. Agustín Zubillaga, se realizó un estudio descriptivo transversal de recolección retrospectiva de datos durante el lapso 2011-2016. Entre las características sociodemográficas se encontró una edad promedio para el momento del diagnóstico de 4,4 ± 2,41 años, siendo los más afectados los preescolares (70%) sin predilección por sexo. Como antecedente prenatal, 90% fue producto de parto vaginal y 30% reportaron asma e infección respiratoria baja. Las características clínicas presentes fueron disfonía (90%), disnea (70%) y estridor (60%) y la localización de las lesiones fueron comisura anterior (100%), repliegues vocales (80% derecho y 90% izquierdo) y vestíbulo (40%). Se reportaron 40% de casos de VPH-6 y 10% de VPH-11. El tratamiento fue quirúrgico en el 100% de los casos, de los cuales 50% requirió una segunda poda y 30% tres podas; 10% de los pacientes ameritaron traqueotomía. Este estudio aporta información sobre la importancia de reconocer tempranamente la disfonía persistente, lo que permite disminuir la demora en el diagnóstico de PRR y facilitar un manejo oportuno con menores tasas de recidiva a largo plazo(AU)


Recurrent respiratory papillomatosis (RRP) is the second most frequent cause of dysphonia during childhood; the most frequent causative agent is human papillomavirus serotypes 6 and 11. In order to describe the clinical and epidemiological characteristics of RRP In pediatric admitted to the Servicio Desconcentrado Hospital Pediátrico Dr. Agustín Zubillaga, a cross-sectional descriptive study was conducted during the 2011-2016 period. The average age of diagnosis was 4.4 ± 2.41 years, with the highest prevalence in preschool children (70%) and with no sex predilection. 90% of patients were product of vaginal delivery and 30% reported asthma and low respiratory infection. The clinical features present were dysphonia (90%), dyspnea (70%) and stridor (60%); location of the lesions were anterior commissure (100%), vocal folds (80% right and 90% left) and vestibule (40%). 40% of patients reported HPV-6 and 10% HPV-11. Treatment was surgical in 100% of cases of which 50% required a second pruning and 30% three pruning; 10% needed a tracheotomy. This study provides information on the importance of early recognition of persistent dysphonia allowing to reduce diagnosis delay of RRP and facilitate timely management with lower rates of long-term recurrence(AU)


Asunto(s)
Humanos , Masculino , Femenino , Preescolar , Papiloma/fisiopatología , Papillomaviridae , Enfermedades Respiratorias/complicaciones , Verrugas , Neoplasias Laríngeas , Disfonía/etiología , Otolaringología , Pediatría , Calidad de Vida/psicología , Enfermedades Respiratorias
4.
Arch Pathol Lab Med ; 142(6): 706-710, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29848037

RESUMEN

CONTEXT: - Human papillomavirus (HPV) has a well-known role in the pathogenesis of squamous cell carcinoma and precursor lesions of the cervix, anogenital region, and head and neck, but its role in the development of squamous neoplasms of the eye, particularly the conjunctiva, remains unclear. OBJECTIVE: - To review recent evidence implicating HPV in the pathophysiology of ocular lesions. DATA SOURCES: - Published articles obtained from a PubMed search of the English literature were the primary sources for this review. CONCLUSIONS: - The low-risk HPV types 6 and 11 appear to play a role in the development of at least a subset of conjunctival squamous papillomas. The role of HPV in the pathogenesis of pterygium and ocular surface squamous neoplasia is less well defined. There is evidence to suggest that HPV may be a cofactor in the development of these lesions, acting in concert with ultraviolet radiation and/or human immunodeficiency virus infection in a subgroup of cases.


Asunto(s)
Carcinoma de Células Escamosas/virología , Neoplasias del Ojo/virología , Papillomaviridae/fisiología , Infecciones por Papillomavirus/virología , Pterigion/virología , Carcinoma de Células Escamosas/fisiopatología , Neoplasias de la Conjuntiva/fisiopatología , Neoplasias de la Conjuntiva/virología , Neoplasias del Ojo/fisiopatología , Papillomavirus Humano 11/fisiología , Papillomavirus Humano 16/fisiología , Humanos , Papiloma/fisiopatología , Papiloma/virología , Infecciones por Papillomavirus/fisiopatología , Pterigion/fisiopatología , Rayos Ultravioleta
5.
Arch. argent. pediatr ; 116(3): 471-475, jun. 2018. ilus
Artículo en Español | LILACS, BINACIS | ID: biblio-950030

RESUMEN

La papilomatosis laríngea juvenil es una enfermedad infrecuente causada por el virus del papiloma humano, principalmente, los tipos 6 y 11. Es el tumor laríngeo benigno más común en los niños. Debe pensarse, en esta patología, en todo niño con disfonía persistente y progresiva, acompañada o no de estridor y dificultad respiratoria. La laringoscopía flexible con anestesia local permite visualizar las típicas lesiones de características verrugosas. El diagnóstico se confirma mediante la anatomía patológica. El tratamiento existente es paliativo y consiste, principalmente, en la escisión quirúrgica de los papilomas para mantener la vía aérea sin obstrucción y mejorar la calidad de la voz, pero tiene una alta tasa de recidiva. Se presentan 20 pacientes con papilomatosis laríngea juvenil. Se describen las manifestaciones clínicas, el diagnóstico y el tratamiento de esta patología.


Juvenile laryngeal papillomatosis is an uncommon disease caused by human papilloma virus, mainly types 6 and 11. It is the most common benign laryngeal tumor in children. This condition should be suspected in any children with persistent and progressive dysphonia with or without stridor and respiratory distress. Flexible laryngoscopy under local anesthesia allows to visualize the typical wart-like lesions. The diagnosis is confirmed by pathological anatomy. Existing treatment is palliative and consists mainly of the surgical excision of the papillomas to maintain the airway without obstruction and to improve the quality of the voice, but it has a high rate of relapse. We present 20 patients with juvenile laryngeal papillomatosis. We describe the clinical manifestations, the diagnostic methods and the treatment of this pathology.


Asunto(s)
Humanos , Masculino , Femenino , Recién Nacido , Lactante , Preescolar , Niño , Papiloma/diagnóstico , Neoplasias Laríngeas/diagnóstico , Disfonía/etiología , Laringoscopía/métodos , Papiloma/fisiopatología , Papiloma/terapia , Neoplasias Laríngeas/fisiopatología , Neoplasias Laríngeas/terapia , Anestésicos Locales/administración & dosificación
6.
Arch Argent Pediatr ; 116(3): e471-e475, 2018 06 01.
Artículo en Español | MEDLINE | ID: mdl-29756727

RESUMEN

Juvenile laryngeal papillomatosis is an uncommon disease caused by human papilloma virus, mainly types 6 and 11. It is the most common benign laryngeal tumor in children. This condition should be suspected in any children with persistent and progressive dysphonia with or without stridor and respiratory distress. Flexible laryngoscopy under local anesthesia allows to visualize the typical wart-like lesions. The diagnosis is confirmed by pathological anatomy. Existing treatment is palliative and consists mainly of the surgical excision of the papillomas to maintain the airway without obstruction and to improve the quality of the voice, but it has a high rate of relapse. We present 20 patients with juvenile laryngeal papillomatosis. We describe the clinical manifestations, the diagnostic methods and the treatment of this pathology.


La papilomatosis laríngea juvenil es una enfermedad infrecuente causada por el virus del papiloma humano, principalmente, los tipos 6 y 11. Es el tumor laríngeo benigno más común en los niños. Debe pensarse, en esta patología, en todo niño con disfonía persistente y progresiva, acompañada o no de estridor y dificultad respiratoria. La laringoscopía flexible con anestesia local permite visualizar las típicas lesiones de características verrugosas. El diagnóstico se confirma mediante la anatomía patológica. El tratamiento existente es paliativo y consiste, principalmente, en la escisión quirúrgica de los papilomas para mantener la vía aérea sin obstrucción y mejorar la calidad de la voz, pero tiene una alta tasa de recidiva. Se presentan 20 pacientes con papilomatosis laríngea juvenil. Se describen las manifestaciones clínicas, el diagnóstico y el tratamiento de esta patología.


Asunto(s)
Disfonía/etiología , Neoplasias Laríngeas/diagnóstico , Laringoscopía/métodos , Papiloma/diagnóstico , Anestésicos Locales/administración & dosificación , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Neoplasias Laríngeas/fisiopatología , Neoplasias Laríngeas/terapia , Masculino , Papiloma/fisiopatología , Papiloma/terapia
8.
J BUON ; 21(5): 1274-1278, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27837633

RESUMEN

PURPOSE: Laryngeal papillomatosis can be an aggressive and potentially life-threatening disease, affecting both children and adults. Local excision is the gold standard of treatment, but recurrences are frequently inevitable. The purpose of this study was to present the experience of three institutions with different therapeutic modalities and discuss them in relation with the relevant literature. METHODS: Sixty patients underwent papilloma resection during the last decade in three institutions (Homburg/Saar and Marburg, Germany and Athens,Greece). Patient data were retrospectively analyzed for therapeutic modalities applied, rate of complications and synechia formation, necessary operations and need for tracheostomy. RESULTS: Carbon dioxide laser therapy was the most common modality applied alone or combined with other treatment modalities. No major complication was observed, while glottic synechia was the most common minor complication in 5 (8.3%) patients. Of the patient cohort 55.6% required reoperation, while no patient required tracheostomy. CONCLUSIONS: Surgical debulking with or without adjuvant treatment remains the mainstay of treatment, which mainly aims to reduce the number and frequency of recurrences since no definitive curative therapy is known so far.


Asunto(s)
Neoplasias Laríngeas/cirugía , Terapia por Láser , Papiloma/cirugía , Adolescente , Adulto , Anciano , Antiinfecciosos/uso terapéutico , Niño , Preescolar , Supervivencia sin Enfermedad , Femenino , Humanos , Neoplasias Laríngeas/diagnóstico , Neoplasias Laríngeas/fisiopatología , Laringoscopía , Terapia por Láser/efectos adversos , Terapia por Láser/instrumentación , Láseres de Gas , Masculino , Persona de Mediana Edad , Papiloma/diagnóstico , Papiloma/fisiopatología , Vacunas contra Papillomavirus/uso terapéutico , Fotoquimioterapia , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Recurrencia , Reoperación , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
11.
Pathol Res Pract ; 210(2): 105-10, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24268498

RESUMEN

The expression profiles of 14-3-3ß and θ isoforms, known to exert both oncogenic and antiapoptotic effects, were assessed in different entities of nasal pathophysiology. Flow cytometry and immunohistochemistry were used on paraffin-embedded sections of 51 inverted papillomas (IP), 26 nasal polyps (NP), 9 polyps with IP (NPIP) and 10 specimens of normal epithelium (NE). 14-3-3ß expression was significantly upregulated in IP as compared with both NP (p=0.015) and NE (p=0.002). 14-3-3ß was also increased in NPIP as compared with NE (p=0.008). 14-3-3ß cytoplasmic staining was more pronounced in basal cells of the respiratory epithelium although serous glands and the vascular system were often positive as well. High 14-3-3ß immunopositivity in IP patients concurred with increased proliferative activity shown by PCNA immunostaining (p=0.04). Expression of 14-3-3θ was also found increased in IP and NPIP patients, compared to NP (p=0.005, p=0.002 respectively) and NE (p=0.004 and p=0.001 respectively). 14-3-3θ cytoplasmic immunopositivity was detected in columnar epithelium, particularly in basal and subluminal cells, whereas no immunoreactivity was observed in NP and NE. Our results demonstrate differential expression of 14-3-3ß and θ isoforms in sinonasal pathophysiology, supporting their implication, respectively, in the proliferative and inflammatory process engaged in the formation of IP.


Asunto(s)
Proteínas 14-3-3/metabolismo , Regulación Neoplásica de la Expresión Génica , Pólipos Nasales/metabolismo , Neoplasias Nasales/metabolismo , Papiloma Invertido/metabolismo , Papiloma/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis , Proliferación Celular , Estudios de Cohortes , Células Epiteliales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mucosa Nasal/metabolismo , Pólipos Nasales/fisiopatología , Neoplasias Nasales/fisiopatología , Papiloma/fisiopatología , Papiloma Invertido/fisiopatología , Isoformas de Proteínas , Adulto Joven
12.
Tohoku J Exp Med ; 231(4): 315-9, 2013 12.
Artículo en Inglés | MEDLINE | ID: mdl-24366355

RESUMEN

Sinonasal papilloma is a common benign epithelial tumor of the sinonasal tract and accounts for 0.5% to 4% of all nasal tumors. The etiology of sinonasal papilloma remains unclear, although human papilloma virus has been proposed as a major risk factor. Other etiological factors, such as anatomical variations of the nasal cavity, may be related to the pathogenesis of sinonasal papilloma, because deviated nasal septum is seen in patients with chronic rhinosinusitis. We, therefore, investigated the involvement of deviated nasal septum in the development of sinonasal papilloma. Preoperative computed tomography or magnetic resonance imaging findings of 83 patients with sinonasal papilloma were evaluated retrospectively. The side of papilloma and the direction of septal deviation showed a significant correlation. Septum deviated to the intact side in 51 of 83 patients (61.4%) and to the affected side in 18 of 83 patients (21.7%). Straight or S-shaped septum was observed in 14 of 83 patients (16.9%). Even after excluding 27 patients who underwent revision surgery and 15 patients in whom the papilloma touched the concave portion of the nasal septum, the concave side of septal deviation was associated with the development of sinonasal papilloma (p = 0.040). The high incidence of sinonasal papilloma in the concave side may reflect the consequences of the traumatic effects caused by wall shear stress of the high-velocity airflow and the increased chance of inhaling viruses and pollutants. The present study supports the causative role of human papilloma virus and toxic chemicals in the occurrence of sinonasal papilloma.


Asunto(s)
Tabique Nasal/anomalías , Tabique Nasal/patología , Papiloma/fisiopatología , Sinusitis/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Papillomavirus Humano 11/metabolismo , Papillomavirus Humano 6/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Papiloma/complicaciones , Estudios Retrospectivos , Factores de Riesgo , Sinusitis/complicaciones
14.
Cancer Res ; 73(6): 1742-51, 2013 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-23319805

RESUMEN

Nonresolving inflammation is a hallmark of many types of tumors and the molecular mechanisms maintaining this inflammation are still largely unknown. In a two-stage carcinogenesis model, we observed here that the lack of IFN-γ receptor or neutralization of IFN-γ accelerated spontaneous papilloma regression in mice. The impaired maintenance of local inflammation was associated with reduced IFN-γ and enhanced biosynthesis of proresolution lipid mediator lipoxin A4 (LXA4). Interestingly, blocking LXA4 eliminated the effect of anti-IFN-γ, whereas treatment of mice with a therapeutic dose of LXA4 accelerated papilloma regression in an IFN-γ-independent manner. These results link for the first time a cytokine-dependent maintenance of inflammation with a downregulated production of proresolution lipid mediators. Strategies promoting spontaneous resolution of chronic inflammation by blocking IFN-γ and/or increasing LXA4 may be useful for the treatment of inflammation-associated tumors.


Asunto(s)
Regulación hacia Abajo/fisiología , Interferón gamma/fisiología , Lipoxinas/fisiología , Papiloma/metabolismo , Animales , Apoptosis , Secuencia de Bases , Proliferación Celular , Cartilla de ADN , Citometría de Flujo , Ratones , Ratones Noqueados , Papiloma/patología , Papiloma/fisiopatología , Reacción en Cadena en Tiempo Real de la Polimerasa
15.
J Eur Acad Dermatol Venereol ; 27(1): e119-23, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22050084

RESUMEN

BACKGROUND: Confluent and reticulate papillomatosis (CRP) is a rare disorder that has mostly been described in case reports and limited case series. Studies on this condition from our region are lacking. OBJECTIVE/METHODS: To describe the clinical and histopathological findings, as well as response to treatment of all patients diagnosed with CRP at the American University of Beirut Medical Center (AUB-MC) between 1999 and 2009, and to compare our findings with those published in the literature. RESULTS: Confluent and reticulate papillomatosis was diagnosed in 10 patients (five men, five women). Mean age at diagnosis was 19 years. Duration of lesions ranged from few months to several years. Skin lesions mainly consisted of reticulated, pigmented macules, patches and plaques. The most common area of involvement was the chest in five cases. The rash was asymptomatic in eight patients. Skin biopsy specimens from all patients revealed hyperkeratosis, papillomatosis and variable acanthosis. Whereas follicular plugging was observed in nine cases, anastomosis of the rete ridges was noted in three. Periodic acid Schiff stains highlighted yeast forms in six cases. CONCLUSION: The clinical and histopathological features of the CRP patients in our study are generally comparable to those published in the literature, with minor differences. Clinically, one case had an atypical clinical presentation, and microscopically follicular plugging was seen in the majority of cases. Yeast-like spores were seen in six cases further supporting a role of Malassezia furfur in the pathogenesis of CRP.


Asunto(s)
Papiloma/tratamiento farmacológico , Papiloma/patología , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/patología , Administración Oral , Administración Tópica , Adolescente , Adulto , Biopsia con Aguja , Estudios de Cohortes , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Inmunohistoquímica , Líbano , Masculino , Minociclina/uso terapéutico , Papiloma/fisiopatología , Enfermedades Raras , Estudios Retrospectivos , Neoplasias Cutáneas/fisiopatología , Esteroides/uso terapéutico , Resultado del Tratamiento , Tretinoina/uso terapéutico
16.
EMBO J ; 31(24): 4563-75, 2012 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-23188079

RESUMEN

Cancer stem cells have been described in various cancers including squamous tumours of the skin by their ability to reform secondary tumours upon transplantation into immunodeficient mice. Here, we used transplantation of limiting dilution of different populations of FACS-isolated tumour cells from four distinct mouse models of squamous skin tumours to investigate the frequency of tumour propagating cells (TPCs) at different stages of tumour progression. We found that benign papillomas, despite growing rapidly in vivo and being clonogenic in vitro, reformed secondary tumours upon transplantation at very low frequency and only when tumour cells were co-transplanted together with tumour-associated fibroblasts or endothelial cells. In two models of skin squamous cell carcinoma (SCC), TPCs increased with tumour invasiveness. Interestingly, the frequency of TPCs increased in CD34(HI) but not in CD34(LO) SCC cells with serial transplantations, while the two populations initially gave rise to secondary tumours with the same frequency. Our results illustrate the progressive increase of squamous skin TPCs with tumour progression and invasiveness and reveal that serial transplantation may be required to define the long-term renewal potential of TPCs.


Asunto(s)
Carcinoma de Células Escamosas/fisiopatología , Modelos Biológicos , Invasividad Neoplásica/fisiopatología , Células Madre Neoplásicas/fisiología , Neoplasias Cutáneas/fisiopatología , Animales , Antígenos CD34/metabolismo , Proliferación Celular , Cartilla de ADN/genética , Progresión de la Enfermedad , Citometría de Flujo , Técnicas Histológicas , Ratones , Ratones SCID , Células Madre Neoplásicas/citología , Papiloma/fisiopatología , Reacción en Cadena en Tiempo Real de la Polimerasa , Trasplante de Células Madre , Tamoxifeno
17.
Ann Otol Rhinol Laryngol ; 120(1): 17-20, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21370676

RESUMEN

We performed a retrospective chart review with a 6-month follow-up to examine the initial use of propranolol as an adjunctive treatment in children with severe recurrent respiratory papillomatosis. This is the first such report. Two of 3 children with severe recurrent respiratory papillomatosis demonstrated a response to oral propranolol therapy, as evidenced by an improved voice and by an increased time between surgical interventions. One child demonstrated no response to propranolol, and medication was halted. Both children who demonstrated a response had undergone more than 10 surgical interventions in the previous year, along with prior treatment including surgical excision and adjuvant therapy. Both children more than doubled the interval between treatments after propranolol administration, and the parents of both children noted marked improvement of the child's voice as measured by their Pediatric Voice-Related Quality of Life score (from 40 to 67.5 in one child and from 27 to 60 in the other child). No child experienced hypoglycemia or blood pressure abnormalities. We conclude that initial use of propranolol as an adjunctive measure in severe recurrent respiratory papillomatosis shows it to have some efficacy in delaying surgical intervention and improving voice. Previous reports have demonstrated relatively safe use of propranolol in children with hemangiomas. Further studies are needed to determine the long-term effectiveness, dosing strategies, and side-effect profile of propranolol for treatment of recurrent respiratory papillomatosis.


Asunto(s)
Neoplasias Laríngeas/tratamiento farmacológico , Papiloma/tratamiento farmacológico , Propranolol/administración & dosificación , Administración Oral , Adolescente , Niño , Preescolar , Disfonía/tratamiento farmacológico , Disfonía/fisiopatología , Femenino , Humanos , Neoplasias Laríngeas/fisiopatología , Neoplasias Laríngeas/cirugía , Masculino , Papiloma/fisiopatología , Papiloma/cirugía , Propranolol/efectos adversos , Recurrencia , Estudios Retrospectivos , Voz
18.
Carcinogenesis ; 31(6): 1116-23, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20172950

RESUMEN

Transforming growth factor beta1 (TGFbeta1) expression is elevated by tumor promoters in the mouse skin, but its role in tumor promotion has not been well defined. To investigate this, we have compared TGFbeta1+/+ and +/- mice in a two-stage skin chemical carcinogenesis protocol. Surprisingly, TGFbeta1+/- mice had fewer number and incidence of benign papillomas, reduced epidermal and tumor cell proliferation and reduced epidermal TGFbeta1 and nuclear p-Smad2 localization in response to the tumor promoter 12-O-tetradecanoylphorbol 13-acetate (TPA) compared with TGFbeta1+/+ mice. Maximal TPA activation of protein kinase C (PKCalpha) as measured by activity assays and activation of target genes and induction of cornified envelopes correlated with TGFbeta1 gene dosage in keratinocytes and addition of exogenous TGFbeta1 restored the cornification defect in TGFbeta1+/- keratinocytes. Similarly, inhibition of ALK5-suppressed TPA-mediated PKCalpha activation suggesting that physiological levels of TGFbeta1 are required for maximal activation of PKC-dependent mitogenic responses. Paradoxically, the TPA-induced inflammatory response was greater in TGFbeta1+/- skin, but TGFbeta1+/+ papillomas had more tumor infiltrating myeloperoxidase-positive cells and pro-inflammatory gene expression was elevated in v-ras(Ha)-transduced TGFbeta1+/+ but not TGFbeta1+/- keratinocytes. Thus, ras activation switches TGFbeta1 to a pro-inflammatory cytokine. Despite this differential proliferative and inflammatory response to TPA and enhanced papilloma formation in the TGFbeta1+/+ mice, the frequency of malignant conversion was reduced compared with TGFbeta1+/- mice. Therefore, TGFbeta1 promotes benign tumors by modifying tumor promoter-induced cell proliferation and inflammation but retains a suppressive function for malignant conversion.


Asunto(s)
Papiloma/fisiopatología , Neoplasias Cutáneas/fisiopatología , Factor de Crecimiento Transformador beta1/fisiología , Animales , Carcinógenos/toxicidad , Proliferación Celular , Transformación Celular Neoplásica , Ratones , Ratones Endogámicos BALB C , Papiloma/inducido químicamente , Papiloma/patología , Neoplasias Cutáneas/inducido químicamente , Neoplasias Cutáneas/patología , Acetato de Tetradecanoilforbol/toxicidad
19.
Hum Mol Genet ; 19(8): 1387-98, 2010 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-20080939

RESUMEN

PRKAR1A inactivation leads to dysregulated cAMP signaling and Carney complex (CNC) in humans, a syndrome associated with skin, endocrine and other tumors. The CNC phenotype is not easily explained by the ubiquitous cAMP signaling defect; furthermore, Prkar1a(+/-) mice did not develop skin and other CNC tumors. To identify whether a Prkar1a defect is truly a generic but weak tumorigenic signal that depends on tissue-specific or other factors, we investigated Prkar1a(+/-) mice when bred within the Rb1(+/-) or Trp53(+/-) backgrounds, or treated with a two-step skin carcinogenesis protocol. Prkar1a(+/-) Trp53(+/-) mice developed more sarcomas than Trp53(+/-) mice (P < 0.05) and Prkar1a(+/-) Rb1(+/-) mice grew more (and larger) pituitary and thyroid tumors than Rb1(+/-) mice. All mice with double heterozygosity had significantly reduced life-spans compared with their single-heterozygous counterparts. Prkar1a(+/-) mice also developed more papillomas than wild-type animals. A whole-genome transcriptome profiling of tumors produced by all three models identified Wnt signaling as the main pathway activated by abnormal cAMP signaling, along with cell cycle abnormalities; all changes were confirmed by qRT-PCR array and immunohistochemistry. siRNA down-regulation of Ctnnb1, E2f1 or Cdk4 inhibited proliferation of human adrenal cells bearing a PRKAR1A-inactivating mutation and Prkar1a(+/-) mouse embryonic fibroblasts and arrested both cell lines at the G0/G1 phase of the cell cycle. In conclusion, Prkar1a haploinsufficiency is a relatively weak tumorigenic signal that can act synergistically with other tumor suppressor gene defects or chemicals to induce tumors, mostly through Wnt-signaling activation and cell cycle dysregulation, consistent with studies in human neoplasms carrying PRKAR1A defects.


Asunto(s)
Ciclo Celular , Subunidad RIalfa de la Proteína Quinasa Dependiente de AMP Cíclico/genética , Neoplasias/genética , Neoplasias/patología , Proteína de Retinoblastoma/genética , Transducción de Señal , Proteína p53 Supresora de Tumor/genética , Proteínas Wnt/metabolismo , Animales , Subunidad RIalfa de la Proteína Quinasa Dependiente de AMP Cíclico/metabolismo , Modelos Animales de Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Haploidia , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Neoplasias/metabolismo , Neoplasias/fisiopatología , Procesos Neoplásicos , Papiloma/inducido químicamente , Papiloma/genética , Papiloma/metabolismo , Papiloma/fisiopatología , Proteína de Retinoblastoma/metabolismo , Neoplasias Cutáneas/inducido químicamente , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/fisiopatología , Proteína p53 Supresora de Tumor/metabolismo , Proteínas Wnt/genética
20.
Braz J Biol ; 69(3): 899-905, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19802451

RESUMEN

Chelonia mydas is a sea turtle that feeds and nests on the Brazilian coast and a disease called fibropapillomatosis is a threat to this species. Because of this, it is extremely necessary to determine a methodology that would enable the analysis of blood leukocyte function in these sea turtles. In order to achieve this aim, blood samples were collected from C. mydas with or without fibropapillomas captured on the São Paulo north coast. Blood samples were placed in tubes containing sodium heparin and were transported under refrigeration to the laboratory in sterile RPMI 1640 cell culture medium. Leukocytes were separated by density gradient using Ficoll-PaqueTM Plus, Amershan Biociences. The following stimuli were applied in the assessment of leukocyte function: Phorbol Miristate-Acetate (PMA) for oxidative burst activity evaluation and Zymosan A (Saccharomyces cerevisiae) Bio Particles, Alexa Fluor 594 conjugate for phagocytosis evaluation. Three cell populations were identified: heterophils, monocytes and lymphocytes. Monocytes were the cells responsible for phagocytosis and oxidative burst.


Asunto(s)
Citometría de Flujo/veterinaria , Leucocitos/fisiología , Papiloma/veterinaria , Fagocitosis/fisiología , Estallido Respiratorio/fisiología , Tortugas/sangre , Animales , Citometría de Flujo/métodos , Papiloma/sangre , Papiloma/fisiopatología
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