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1.
Chest ; 159(6): e385-e388, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34099155

RESUMO

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.


Assuntos
Coagulação com Plasma de Argônio/métodos , Biópsia/métodos , Broncoscopia/métodos , Papiloma , Doenças da Traqueia , Estenose Traqueal , Idoso , Diagnóstico Diferencial , Dispneia/diagnóstico , Dispneia/etiologia , Humanos , Imuno-Histoquímica , Masculino , Papiloma/patologia , Papiloma/fisiopatologia , Sons Respiratórios/diagnóstico , Sons Respiratórios/etiologia , Tomografia Computadorizada por Raios X/métodos , Doenças da Traqueia/patologia , Doenças da Traqueia/fisiopatologia , Estenose Traqueal/diagnóstico , Estenose Traqueal/fisiopatologia , Resultado do Tratamento
2.
Bol. méd. postgrado ; 35(2): 51-56, Jul.-Dec. 2019.
Artigo em Espanhol | LILACS, LIVECS | ID: biblio-1120210

RESUMO

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)


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Papiloma/fisiopatologia , Papillomaviridae , Doenças Respiratórias/complicações , Verrugas , Neoplasias Laríngeas , Disfonia/etiologia , Otolaringologia , Pediatria , Qualidade de Vida/psicologia , Doenças Respiratórias
4.
Arch Pathol Lab Med ; 142(6): 706-710, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29848037

RESUMO

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.


Assuntos
Carcinoma de Células Escamosas/virologia , Neoplasias Oculares/virologia , Papillomaviridae/fisiologia , Infecções por Papillomavirus/virologia , Pterígio/virologia , Carcinoma de Células Escamosas/fisiopatologia , Neoplasias da Túnica Conjuntiva/fisiopatologia , Neoplasias da Túnica Conjuntiva/virologia , Neoplasias Oculares/fisiopatologia , Papillomavirus Humano 11/fisiologia , Papillomavirus Humano 16/fisiologia , Humanos , Papiloma/fisiopatologia , Papiloma/virologia , Infecções por Papillomavirus/fisiopatologia , Pterígio/fisiopatologia , Raios Ultravioleta
5.
Arch. argent. pediatr ; 116(3): 471-475, jun. 2018. ilus
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-950030

RESUMO

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.


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Pré-Escolar , Criança , Papiloma/diagnóstico , Neoplasias Laríngeas/diagnóstico , Disfonia/etiologia , Laringoscopia/métodos , Papiloma/fisiopatologia , Papiloma/terapia , Neoplasias Laríngeas/fisiopatologia , Neoplasias Laríngeas/terapia , Anestésicos Locais/administração & dosagem
6.
Arch Argent Pediatr ; 116(3): e471-e475, 2018 06 01.
Artigo em Espanhol | MEDLINE | ID: mdl-29756727

RESUMO

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.


Assuntos
Disfonia/etiologia , Neoplasias Laríngeas/diagnóstico , Laringoscopia/métodos , Papiloma/diagnóstico , Anestésicos Locais/administração & dosagem , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Neoplasias Laríngeas/fisiopatologia , Neoplasias Laríngeas/terapia , Masculino , Papiloma/fisiopatologia , Papiloma/terapia
8.
J BUON ; 21(5): 1274-1278, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27837633

RESUMO

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.


Assuntos
Neoplasias Laríngeas/cirurgia , Terapia a Laser , Papiloma/cirurgia , Adolescente , Adulto , Idoso , Anti-Infecciosos/uso terapêutico , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Laríngeas/diagnóstico , Neoplasias Laríngeas/fisiopatologia , Laringoscopia , Terapia a Laser/efeitos adversos , Terapia a Laser/instrumentação , Lasers de Gás , Masculino , Pessoa de Meia-Idade , Papiloma/diagnóstico , Papiloma/fisiopatologia , Vacinas contra Papillomavirus/uso terapêutico , Fotoquimioterapia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Recidiva , Reoperação , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
11.
Pathol Res Pract ; 210(2): 105-10, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24268498

RESUMO

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.


Assuntos
Proteínas 14-3-3/metabolismo , Regulação Neoplásica da Expressão Gênica , Pólipos Nasais/metabolismo , Neoplasias Nasais/metabolismo , Papiloma Invertido/metabolismo , Papiloma/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Proliferação de Células , Estudos de Coortes , Células Epiteliais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/metabolismo , Pólipos Nasais/fisiopatologia , Neoplasias Nasais/fisiopatologia , Papiloma/fisiopatologia , Papiloma Invertido/fisiopatologia , Isoformas de Proteínas , Adulto Jovem
12.
Tohoku J Exp Med ; 231(4): 315-9, 2013 12.
Artigo em Inglês | MEDLINE | ID: mdl-24366355

RESUMO

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.


Assuntos
Septo Nasal/anormalidades , Septo Nasal/patologia , Papiloma/fisiopatologia , Sinusite/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Papillomavirus Humano 11/metabolismo , Papillomavirus Humano 6/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Papiloma/complicações , Estudos Retrospectivos , Fatores de Risco , Sinusite/complicações
14.
Cancer Res ; 73(6): 1742-51, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23319805

RESUMO

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.


Assuntos
Regulação para Baixo/fisiologia , Interferon gama/fisiologia , Lipoxinas/fisiologia , Papiloma/metabolismo , Animais , Apoptose , Sequência de Bases , Proliferação de Células , Primers do DNA , Citometria de Fluxo , Camundongos , Camundongos Knockout , Papiloma/patologia , Papiloma/fisiopatologia , Reação em Cadeia da Polimerase em Tempo Real
15.
J Eur Acad Dermatol Venereol ; 27(1): e119-23, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22050084

RESUMO

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.


Assuntos
Papiloma/tratamento farmacológico , Papiloma/patologia , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/patologia , Administração Oral , Administração Tópica , Adolescente , Adulto , Biópsia por Agulha , Estudos de Coortes , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Líbano , Masculino , Minociclina/uso terapêutico , Papiloma/fisiopatologia , Doenças Raras , Estudos Retrospectivos , Neoplasias Cutâneas/fisiopatologia , Esteroides/uso terapêutico , Resultado do Tratamento , Tretinoína/uso terapêutico
17.
EMBO J ; 31(24): 4563-75, 2012 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-23188079

RESUMO

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.


Assuntos
Carcinoma de Células Escamosas/fisiopatologia , Modelos Biológicos , Invasividade Neoplásica/fisiopatologia , Células-Tronco Neoplásicas/fisiologia , Neoplasias Cutâneas/fisiopatologia , Animais , Antígenos CD34/metabolismo , Proliferação de Células , Primers do DNA/genética , Progressão da Doença , Citometria de Fluxo , Técnicas Histológicas , Camundongos , Camundongos SCID , Células-Tronco Neoplásicas/citologia , Papiloma/fisiopatologia , Reação em Cadeia da Polimerase em Tempo Real , Transplante de Células-Tronco , Tamoxifeno
18.
Ann Otol Rhinol Laryngol ; 120(1): 17-20, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21370676

RESUMO

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.


Assuntos
Neoplasias Laríngeas/tratamento farmacológico , Papiloma/tratamento farmacológico , Propranolol/administração & dosagem , Administração Oral , Adolescente , Criança , Pré-Escolar , Disfonia/tratamento farmacológico , Disfonia/fisiopatologia , Feminino , Humanos , Neoplasias Laríngeas/fisiopatologia , Neoplasias Laríngeas/cirurgia , Masculino , Papiloma/fisiopatologia , Papiloma/cirurgia , Propranolol/efeitos adversos , Recidiva , Estudos Retrospectivos , Voz
19.
Carcinogenesis ; 31(6): 1116-23, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20172950

RESUMO

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.


Assuntos
Papiloma/fisiopatologia , Neoplasias Cutâneas/fisiopatologia , Fator de Crescimento Transformador beta1/fisiologia , Animais , Carcinógenos/toxicidade , Proliferação de Células , Transformação Celular Neoplásica , Camundongos , Camundongos Endogâmicos BALB C , Papiloma/induzido quimicamente , Papiloma/patologia , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/patologia , Acetato de Tetradecanoilforbol/toxicidade
20.
Hum Mol Genet ; 19(8): 1387-98, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20080939

RESUMO

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.


Assuntos
Ciclo Celular , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/genética , Neoplasias/genética , Neoplasias/patologia , Proteína do Retinoblastoma/genética , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Proteínas Wnt/metabolismo , Animais , Subunidade RIalfa da Proteína Quinase Dependente de AMP Cíclico/metabolismo , Modelos Animais de Doenças , Feminino , Regulação Neoplásica da Expressão Gênica , Haploidia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/metabolismo , Neoplasias/fisiopatologia , Processos Neoplásicos , Papiloma/induzido quimicamente , Papiloma/genética , Papiloma/metabolismo , Papiloma/fisiopatologia , Proteína do Retinoblastoma/metabolismo , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/fisiopatologia , Proteína Supressora de Tumor p53/metabolismo , Proteínas Wnt/genética
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