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1.
Eur Rev Med Pharmacol Sci ; 21(19): 4411-4418, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29077152

RESUMO

OBJECTIVE: The aim of this study was to evaluate the reparative role of hyaluronic acid in acute rhinosinusitis (ARS). PATIENTS AND METHODS: 48 patients affected by ARS were submitted to nasal endoscopy, nasal cytology, mucociliary transport evaluation (MCTt) and visual analogue scale questionnaire (VAS) at T0, after 14-18 days (T1) and after 30-35 days (T2). The patients were randomized into two groups, A and B, and received Levofloxacin and Prednisone. Moreover, using a nebulizer ampoule for nasal douche, Group A received high molecular weight Sodium Hyaluronate (3%) plus saline solution (NaCl 0.9%) twice a day for 30 days; Group B received saline solution twice a day for 30 days. RESULTS: At T0 only the VAS score showed differences regarding nasal discharge and post-nasal drip. At T1, in Group A MCTt and the number of bacteria were significantly lower than in Group B. The VAS score showed improvement in Group A. At T2 in Group A, MCTt and number of neutrophils were significantly lower than in Group B. The VAS score showed statistically significant differences between the two groups regarding nasal discharge. CONCLUSIONS: In ARS patients sodium hyaluronate plus saline solution significantly improved symptoms, MCT time and reduced neutrophil count on nasal cytology.


Assuntos
Ácido Hialurônico/uso terapêutico , Mucosa Nasal/patologia , Rinite/tratamento farmacológico , Rinite/patologia , Sinusite/tratamento farmacológico , Sinusite/patologia , Adulto , Antibacterianos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Depuração Mucociliar/efeitos dos fármacos , Mucosa Nasal/microbiologia , Rinite/microbiologia , Sinusite/microbiologia , Esteroides/uso terapêutico , Resultado do Tratamento
2.
J Biol Regul Homeost Agents ; 30(1): 255-62, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27049100

RESUMO

Allergic rhinitis (AR) is caused by an IgE-mediated inflammatory reaction. Non-allergic rhinitis (NAR) is characterized by a non-IgE-mediated pathogenesis. Frequently, patients have the two disorders associated: such as mixed rhinitis (MR). Hyaluronic acid (HA) is a fundamental component of the human connective tissue. HA may exert anti-inflammatory and immune-modulating activities. Recently, an intranasal HA formulation was proposed: a supramolecular system containing lysine hyaluronate, thymine and sodium chloride (T-LysYal®). This randomized study investigated whether intranasal T-LysYal® (rinoLysYal®, Farmigea, Italy) was able to reduce symptom severity, endoscopic features, and nasal cytology in 89 patients (48 males and 41 females, mean age 36.3±7.1 years) with AR, NAR, and MR. Patients were treated with intranasal T-LysYal® or isotonic saline solution as adjunctive therapy to nasal corticosteroid and oral antihistamine for 4 weeks. Patients were visited at baseline, after treatment and after 4-week follow-up. Intranasal T-LysYal® treatment significantly reduced the quote of patients with symptoms, endoscopic features, and inflammatory cells. In conclusion, the present study demonstrates that intranasal T-LysYal® is able, as ancillary therapy, to significantly improve patients with AR, NAR, and MR, and its effect is long lasting.


Assuntos
Lisina/administração & dosagem , Lisina/uso terapêutico , Rinite Alérgica/tratamento farmacológico , Rinite/tratamento farmacológico , Cloreto de Sódio/administração & dosagem , Cloreto de Sódio/uso terapêutico , Timina/administração & dosagem , Timina/uso terapêutico , Administração Intranasal , Adulto , Feminino , Humanos , Hipertrofia , Masculino , Neutrófilos/patologia , Conchas Nasais/patologia
3.
J Biol Regul Homeost Agents ; 30(1): 277-84, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27049103

RESUMO

Functional Endoscopic Sinus Surgery (FESS) is a common day surgery technique for upper airway disorders. Hyaluronic acid (HA) is a fundamental component of the human connective tissue. HA may exert reparative, anti-inflammatory and immune-modulating activities. Recently, a new intranasal HA formulation has been proposed: a supramolecular system containing lysine hyaluronate, thymine and sodium chloride (T-LysYal®). This randomized study investigated whether intranasal T-LysYal® (RinoLysYal®, Farmigea, Italy) was able to reduce symptom severity, endoscopic features, and nasal cytology in 83 patients (49 males and 34 females mean age 45.4±6.2 years) treated with FESS. All patients were treated with isotonic saline solution for 4 weeks, and a sub-group (active group) was also treated with intranasal T-LysYal®. Patients were visited at baseline, after treatment, and after 4-week follow-up. Intranasal T-LysYal® treatment significantly reduced the quote of patients with symptoms, endoscopic features, and inflammatory cells in comparison to isotonic solution. In conclusion, the present study demonstrates that intranasal T-LysYal® is able to significantly improve patients after FESS and its effect is long lasting.


Assuntos
Adjuvantes Farmacêuticos/administração & dosagem , Adjuvantes Farmacêuticos/farmacologia , Endoscopia , Lisina/administração & dosagem , Lisina/farmacologia , Seios Paranasais/cirurgia , Cloreto de Sódio/administração & dosagem , Cloreto de Sódio/farmacologia , Timina/administração & dosagem , Timina/farmacologia , Administração Intranasal , Contagem de Células , Eosinófilos/efeitos dos fármacos , Eosinófilos/patologia , Feminino , Humanos , Hipertrofia , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/efeitos dos fármacos , Mucosa Nasal/patologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/patologia , Seios Paranasais/patologia , Conchas Nasais/efeitos dos fármacos , Conchas Nasais/patologia
4.
Int J Immunopathol Pharmacol ; 29(2): 151-9, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26684637

RESUMO

Granulomatosis with polyangiitis (GPA), formerly Wegener's granulomatosis (WG), is an uncommon immunologically mediated systemic small-vessel vasculitis that is pathologically characterised by an inflammatory reaction pattern (necrosis, granulomatous inflammation and vasculitis) that occurs in the upper and lower respiratory tracts and kidneys. Although the aetiology of GPA remains largely unknown, it is believed to be autoimmune in origin and triggered by environmental events on a background of genetic susceptibility.In Europe, the prevalence of GPA is five cases per 100,000 population, with greater incidence in Northern Europe. GPA can occur in all racial groups but predominantly affects Caucasians. Both sexes are affected equally. GPA affects a wide age range (age range, 8-99 years).Granulomatosis with polyangiitis is characterised by necrotising granulomatous lesions of the respiratory tract, vasculitis and glomerulonephritis. Classically, the acronym ELK is used to describe the clinical involvement of the ear, nose and throat (ENT); lungs; and kidneys. Because the upper respiratory tract is involved in 70-100% of cases of GPA, classic otorhinolaryngologic symptoms may be the first clinical manifestation of disease. The nasal cavity and the paranasal sinuses are the most common sites of involvement in the head and neck area (85-100%), whereas otological disease is found in approximately 35% (range, 19-61%) of cases.Diagnosis of GPA is achieved through clinical assessment, serological tests for anti-neutrophil cytoplasmic antibodies (ANCA) and histological analysis. The 10-year survival rate is estimated to be 40% when the kidneys are involved and 60-70% when there is no kidney involvement.The standard therapy for GPA is a combination of glucocorticoids and cyclophosphamide. In young patients, cyclophosphamide should be switched to azathioprine in the maintenance phase.A multidisciplinary approach, involving otorhinolaryngologists, oral and maxillofacial surgeons, oral physicians, rheumatologists, renal and respiratory physicians, and ophthalmologists, is necessary for the diagnosis and therapeutic treatment of GPA. ENT physicians have a determining role in recognising the early onset of the disease and starting an appropriate therapy.


Assuntos
Granulomatose com Poliangiite/etiologia , Granulomatose com Poliangiite/patologia , Azatioprina/uso terapêutico , Ciclofosfamida/uso terapêutico , Glucocorticoides/uso terapêutico , Granulomatose com Poliangiite/tratamento farmacológico , Humanos , Incidência , Inflamação/tratamento farmacológico , Inflamação/etiologia , Inflamação/patologia , Rim/patologia , Sistema Respiratório/patologia
6.
Cell Death Differ ; 19(4): 642-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22015606

RESUMO

Using genetically modified mouse models, we report here that p53 upregulated modulator of apoptosis (Puma) and Bcl-2 interacting mediator of cell death (Bim), two pro-apoptotic members of the B-cell lymphoma protein-2 (Bcl-2) family of proteins, cooperate in causing bone marrow and gastrointestinal tract toxicity in response to chemo and radiation therapy. Deletion of both Puma and Bim provides long-term survival without evidence of increased tumor susceptibility following a lethal challenge of carboplatin and ionizing radiation. Consistent with these in vivo findings, studies of primary mast cells demonstrated that the loss of Puma and Bim confers complete protection from cytokine starvation and DNA damage, similar to that observed for Bax/Bak double knockout cells. Biochemical analyses demonstrated an essential role for either Puma or Bim to activate Bax, thereby leading to mitochondrial outer membrane permeability, cytochrome c release and apoptosis. Treatment of cytokine-deprived cells with ABT-737, a BH3 mimetic, demonstrated that Puma is sufficient to activate Bax even in the absence of all other known direct activators, including Bim, Bid and p53. Collectively, our results identify Puma and Bim as key mediators of DNA damage-induced bone marrow failure and provide mechanistic insight into how BH3-only proteins trigger cell death.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Apoptose , Dano ao DNA , Hemoglobinúria Paroxística/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Proteína X Associada a bcl-2/metabolismo , Anemia Aplástica , Animais , Proteínas Reguladoras de Apoptose/genética , Proteína 11 Semelhante a Bcl-2 , Compostos de Bifenilo/farmacologia , Doenças da Medula Óssea , Transtornos da Insuficiência da Medula Óssea , Sobrevivência Celular/genética , Citocromos c/genética , Citocromos c/metabolismo , Deleção de Genes , Hemoglobinúria Paroxística/genética , Hemoglobinúria Paroxística/patologia , Mastócitos/metabolismo , Mastócitos/patologia , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Membranas Mitocondriais/metabolismo , Membranas Mitocondriais/patologia , Nitrofenóis/farmacologia , Permeabilidade , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas/genética , Sulfonamidas/farmacologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/genética , Proteína X Associada a bcl-2/genética
7.
Oncogenesis ; 1: e1, 2012 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-23552518

RESUMO

Most inherited TP53 mutations have been identified in individuals with a family cancer predisposition syndrome, in which the activity of p53 mutants is severely reduced. However, germline p53 mutants in children with 'sporadic' adrenocortical or choroid plexus tumors exhibit a wide range of functional activity. Here, we demonstrate the occurrence of a complex germline TP53 mutation in two unrelated families with different cancer phenotypes, neither fulfilling the classic criteria for Li-Fraumeni syndrome. The TP53 mutation consists of a duplication of 7 bp in exon 4, resulting in a frame shift and premature stop signal. Haplotype analysis indicated that the mutation arose independently in the two families. Analysis of the DNA secondary structure predicts the TP53 mutation occurred within a hairpin loop. Additional germline complex mutations occurring within the same region of exon 4 have been identified in the IARC database. Our findings suggest that certain TP53 regions are prone to intrinsic genetic alterations, possibly through defects in DNA replication or repair. Further, carriers of the same TP53 mutation can have diverse cancer profiles, illustrating the complexity of genetic counseling and risk prediction.

8.
Int J Immunopathol Pharmacol ; 23(2): 641-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20646361

RESUMO

An eosinophilic inflammatory process is generally observed in patients suffering from nasal polyposis (NP), however its onset has not yet been defined. It has been suggested that immune activation of inflammatory cells may be the cause. The aim of this study is to verify whether autoantibodies and/or histamine-releasing factors are present in the serum of patients suffering from NP. In fact, we assume that autoantibodies and/or histamine-releasing factors, as already demonstrated in chronic idiopathic urticaria and asthma, may be involved in the pathogenesis of NP. In this case-control analytical study 40 patients with NP and 27 control subjects underwent the in vivo autologous serum skin test (ASST). The sera from 6 patients suffering from NP and 9 control group subjects, who had all been previously studied and randomly selected, underwent basophil histamine release assay from normal donor as a pilot study. The ASST showed positive results in 55% of patients suffering from NP versus 8% of the control group (p= .00006), the basophil histamine release test (BHRT) turned out positive in all patients tested and in 11% of the control group. We found a weak positive correlation between the percentage of histamine release and the wheal diameter. ASST reactivity is very frequent in patients suffering from NP, thus suggesting the presence of histamine-releasing factors in the blood stream. The BHRT was positive in the serum of all patients, thus suggesting the presence of anti-FcepsilonRI, anti-IgE autoantibodies and/or other histamine-releasing factors, the presence of which can play a role in triggering and maintaining the eosinophilic inflammatory process in NP.


Assuntos
Basófilos/metabolismo , Liberação de Histamina , Pólipos Nasais/imunologia , Soro/imunologia , Testes Cutâneos , Adulto , Idoso , Autoanticorpos/sangue , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pólipos Nasais/metabolismo
9.
Acta Otorhinolaryngol Ital ; 30(1): 58-63, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20559475

RESUMO

Lipoma is a benign tumour of mesenchymal origin with a very rare occurrence in the upper aero-digestive tract. To date, approximately 100 cases have been described in the literature. This lesion has a slow growth and, therefore, can present with various symptoms due to the mass effect with obstruction and compression on neighbouring structures, including dysphagia for liquid and solid food, dyspnoea and hoarseness. For a precise pre-operative diagnosis, indirect or direct laryngoscopy (flexible fibre-optic laryngoscopy) can be employed or, if necessary, also imaging techniques such as computed tomography scan and magnetic resonance imaging scan. These offer more useful information for better treatment planning. Surgery is the treatment of choice and includes endoscopic techniques and an external surgical approach (cervicotomy). It is very important to completely remove these benign neoplasms in order to avoid local recurrence. The present report referring to a case of laryngeal lipoma removed through an external surgical approach, aims to demonstrate that the choice of an external surgical approach is required for complete surgical removal of a large lipoma in order to prevent any possible recurrence. Furthermore, it is useful to keep in mind the possibility of recurrence of lipomas after long free intervals; therefore, it is mandatory to observe these patients at long-term follow-up.


Assuntos
Neoplasias Laríngeas , Lipoma , Humanos , Neoplasias Laríngeas/diagnóstico , Lipoma/diagnóstico , Masculino , Pessoa de Meia-Idade
10.
Cell Death Differ ; 16(9): 1192-202, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19444283

RESUMO

Tumor necrosis factor-alpha (TNF-alpha) is a cytokine that has an important role in immunity and inflammation by inducing cellular responses such as apoptosis. The transcription factor nuclear factor-kappaB (NF-kappaB) can paradoxically suppress and promote apoptosis in response to TNF-alpha. In this study, we found that p53 upregulated modulator of apoptosis (PUMA), a p53 downstream target and a BH3-only Bcl-2 family member, is directly regulated by NF-kappaB in response to TNF-alpha. TNF-alpha treatment led to increases in PUMA mRNA and protein levels in human colon cancer cells. The induction of PUMA was p53 independent, and mediated by the p65 component of NF-kappaB through a kappaB site in the PUMA promoter. The apoptotic effect of PUMA induction by TNF-alpha was unmasked by depleting the antiapoptotic protein Bcl-X(L). In mice, PUMA was also induced by TNF-alpha in an NF-kappaB-dependent manner. TNF-alpha-induced apoptosis in a variety of tissues and cell types, including small intestinal epithelial cells, hepatocytes, and thymocytes, was markedly reduced in PUMA-deficient mice. Collectively, these results demonstrated that PUMA is a direct target of NF-kappaB and mediates TNF-alpha-induced apoptosis in vitro and in vivo.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Animais , Apoptose , Proteínas Reguladoras de Apoptose/genética , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Linhagem Celular Tumoral , Humanos , Camundongos , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas/genética , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Proteína bcl-X/metabolismo
11.
J Med Genet ; 45(9): 603-6, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18762572

RESUMO

Paediatric choroid plexus carcinomas (CPC) and adrenocortical carcinomas (ACC) are exceedingly rare tumours, each occurring at an annual rate of 0.3 cases per million children or less. Although both tumour types are associated with Li-Fraumeni syndrome (LFS), the penetrance of germline TP53 mutations in CPC remains to be established. We report here a young boy without a family history of cancer who presented with CPC and subsequently ACC. Genetic testing revealed a novel de novo germline TP53 mutation (E285V). Neither tumour underwent loss of heterozygosity. Consistent with this observation, functional analyses demonstrated that E285V acts as a dominant negative mutant that is defective in regulating target gene expression, growth suppression and apoptosis. These results further strengthen the association between germline TP53 mutations and childhood CPC, even when occurring in the absence of familial tumour susceptibility.


Assuntos
Neoplasias do Córtex Suprarrenal/genética , Carcinoma Adrenocortical/genética , Carcinoma/genética , Neoplasias do Plexo Corióideo/genética , Genes p53 , Mutação em Linhagem Germinativa , Segunda Neoplasia Primária/genética , Neoplasias do Córtex Suprarrenal/diagnóstico , Neoplasias do Córtex Suprarrenal/metabolismo , Carcinoma Adrenocortical/diagnóstico , Carcinoma Adrenocortical/metabolismo , Carcinoma/diagnóstico , Carcinoma/metabolismo , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Neoplasias do Plexo Corióideo/diagnóstico , Neoplasias do Plexo Corióideo/metabolismo , Humanos , Lactente , Masculino , Segunda Neoplasia Primária/diagnóstico , Segunda Neoplasia Primária/metabolismo , Ativação Transcricional , Proteína Supressora de Tumor p53/metabolismo
13.
J Med Genet ; 43(1): 91-6, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16033918

RESUMO

BACKGROUND: An inherited germline P53 mutation has been identified in cases of childhood adrenocortical carcinoma (ACT), a neoplasm with a high incidence in southern Brazil. The penetrance of ACT in carriers of the point mutation, which encodes an arginine-to-histidine substitution at codon 337 of TP53 (R337H), has not been determined. OBJECTIVE: To investigate the penetrance of childhood ACT in carriers of the R337H TP53 mutation. METHODS: The family histories of 30 kindreds of 41 southern Brazilian children with ACT were obtained. A PCR based assay was used to detect this P53 mutation in a large number of relatives of children with ACT. In all, 927 individuals were tested for the mutation, 232 from the non-carrier and 695 (including the 40 probands) from the carrier parental lines. RESULTS: 40 children with ACT carried the TP53 R337H mutation; the remaining child with ACT was not tested. There was no evidence of Li-Fraumeni syndrome in any of the kindreds; however, seven met the criteria for Li-Fraumeni-like syndrome. The carrier parental line was identified in each kindred. Of the 695 individuals tested in the carrier parental line, 240 (34.5%) were positive for the mutation, while none of the 232 individuals in the other parental line carried the mutation. The penetrance of ACT was 9.9% (95% confidence interval, 8.7% to 11.1%). CONCLUSIONS: The TP53 R337H mutation dramatically increases predisposition to childhood ACT but not to other cancers, and explains the increased frequency of ACT observed in this geographic region.


Assuntos
Neoplasias do Córtex Suprarrenal/genética , Predisposição Genética para Doença , Mutação em Linhagem Germinativa/genética , Penetrância , Proteína Supressora de Tumor p53/genética , Distribuição por Idade , Criança , Pré-Escolar , Feminino , Genótipo , Humanos , Lactente , Masculino , Linhagem , Fatores de Risco
14.
Clin Otolaryngol ; 30(2): 128-34, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15839864

RESUMO

OBJECTIVES: Each nasal area, as defined by Cottle, has a different influence on the nasal airflow. The longitudinal distribution of resistances in nasal cavities was calculated by the anterior rhinomanometry and acoustic rhinometry data. DESIGN: Dynamic study of Cottle's areas in normal subjects was carried out by rhinomanometry and acoustic rhinometry. SETTING: Study by the Department of Otolaryngology of the University of Rome-La Sapienza. PARTICIPANTS: Twenty-seven Caucasian adults in local and general healthy conditions took part and completed this study, with a total of 54 nasal cavities included because of negativity at ENT-examination and clinical history, with normal respiratory parameters at the rhinomanometry and acoustic rhinometry. MAIN OUTCOME MEASURES: We determined nasal and acoustic resistances, nasal volumes and cross-sectional surface areas, as defined by Cottle, using nasal endoscopy. The longitudinal distribution of nasal resistances was obtained by integrating experimental surface areas using a novel mathematical model. The estimation of the longitudinal nasal resistance variations as a result of a theoretical reduction of the surface areas. RESULTS: The reduction of the 2-3-1 areas (in this order of importance) showed the greatest influence on the nasal resistances with coefficients of determinations greater than 0.98, this being quite different from that of the areas 4 and 5 for quite smaller area reduction percentages. CONCLUSIONS: The areas 2-3-1 control the overall nasal resistance so the surgical procedures on these areas greatly influence the dynamics of nasal airflow. The mathematical model developed here gives useful information to nasal functional surgery and may be applied to other schemes of nasal cavity.


Assuntos
Acústica/instrumentação , Modelos Teóricos , Rinomanometria/métodos , Rinomanometria/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Cavidade Nasal/fisiologia
16.
Oncogene ; 20(48): 6983-93, 2001 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-11704823

RESUMO

Malignant transformation occurs in cells that overexpress c-Myc or that inappropriately activate E2F-1. Transformation occurs after the selection of cells that have acquired resistance to apoptosis that is triggered by these oncogenes, and a key mediator of this cell death process is the p53 tumor suppressor. In IL-3-dependent immortal 32D.3 myeloid cells the ARF/p53 apoptotic pathway is inactivated, as these cells fail to express ARF. Nonetheless, both c-Myc and E2F-1 overexpression accelerated apoptosis when these cells were deprived of IL-3. Here we report that c-Myc or E2F-1 overexpression suppresses Bcl-2 protein and RNA levels, and that restoration of Bcl-2 protein effectively blocks the accelerated apoptosis that occurs when c-Myc- or E2F-1-overexpressing cells are deprived of IL-3. Blocking p53 activity with mutant p53 did not abrogate E2F-1-induced suppression of Bcl-2. Analysis of immortal myeloid cells engineered to overexpress c-Myc and E2F-1 DNA binding mutants revealed that DNA binding activity of these oncoproteins is required to suppress Bcl-2 expression. These results suggest that the targeting of Bcl-2 family members is an important mechanism of oncogene-induced apoptosis, and that this occurs independent of the ARF/p53 pathway.


Assuntos
Apoptose/fisiologia , Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Genes bcl-2 , Células Mieloides/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Proteínas Proto-Oncogênicas c-myc/fisiologia , Fatores de Transcrição/fisiologia , Animais , Apoptose/genética , Linhagem Celular Transformada , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , DNA/genética , DNA/metabolismo , Fatores de Transcrição E2F , Fator de Transcrição E2F1 , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Genes myc , Genes p53 , Interleucina-3/farmacologia , Camundongos , Mutação , Células Mieloides/efeitos dos fármacos , Células Mieloides/patologia , Ligação Proteica , Conformação Proteica , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Recombinantes de Fusão/fisiologia , Temperatura , Fatores de Transcrição/genética , Transfecção , Proteína Supressora de Tumor p14ARF/deficiência , Proteína Supressora de Tumor p14ARF/genética , Proteína Supressora de Tumor p14ARF/fisiologia , Proteína Supressora de Tumor p53/fisiologia , Proteína bcl-X
17.
Gene ; 277(1-2): 15-30, 2001 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-11602342

RESUMO

The tumor suppressor p53 plays a central role in the protection against DNA damage and other forms of physiological stress primarily by inducing cell cycle arrest or apoptosis. Mutation of p53, which is the most frequent genetic alteration detected in human cancers, inactivates these growth regulatory functions and causes a loss of tumor suppressor activity. In some cases, mutation also confers tumor-promoting functions, such as the transcriptional activation of genes involved in cell proliferation, cell survival and angiogenesis. Consequently, cells expressing some forms of mutant p53 show enhanced tumorigenic potential with increased resistance to chemotherapy and radiation. Our current understanding of these activities is summarized in this review. By dissecting out mechanistic differences between wild-type and mutant p53 activities, it may be possible to develop therapeutics that restore tumor suppressor function to mutant p53 or that selectively inactivate mutant p53 tumor-promoting functions.


Assuntos
Divisão Celular/fisiologia , Proteína Supressora de Tumor p53/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Sequência de Aminoácidos , Animais , Divisão Celular/genética , Regulação da Expressão Gênica , Humanos , Modelos Biológicos , Dados de Sequência Molecular , Mutação , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genética
18.
Proc Natl Acad Sci U S A ; 98(20): 11318-23, 2001 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-11572983

RESUMO

BH3-only proteins function at a proximal point in a conserved cell death pathway by binding, through their BH3 domains, to other Bcl-2 family members and triggering mitochondrial events associated with apoptosis. Here, we describe a strongly pro-apoptotic BH3-only protein, designated Bbc3, whose expression increases in response to diverse apoptotic stimuli. bbc3 mRNA levels were induced by exposure to DNA-damaging agents and by wild-type p53, which mediates DNA damage-induced apoptosis. p53 transactivated bbc3 through consensus p53 binding sites within the bbc3 promoter region, indicating that bbc3 is a direct target of p53. Additionally, bbc3 mRNA was induced by p53-independent apoptotic stimuli, including dexamethasone treatment of thymocytes, and serum deprivation of tumor cells. Insulin-like growth factor-1 and epidermal growth factor, growth factors with broad anti-apoptotic activity, were each sufficient to suppress Bbc3 expression in serum-starved tumor cells. These results suggest that the transcriptional regulation of bbc3 contributes to the transduction of diverse cell death and survival signals.


Assuntos
Apoptose/genética , Regulação da Expressão Gênica/fisiologia , Proteínas/genética , Proteínas Proto-Oncogênicas , Transdução de Sinais/fisiologia , Proteína Supressora de Tumor p53/metabolismo , Sequência de Aminoácidos , Animais , Proteínas Reguladoras de Apoptose , Sequência de Bases , Sítios de Ligação , Morte Celular , Sobrevivência Celular , Células Cultivadas , Sequência Consenso , Fibroblastos/citologia , Fibroblastos/fisiologia , Genes p53 , Humanos , Leucemia Mieloide , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Fases de Leitura Aberta , Reação em Cadeia da Polimerase , Proteínas/química , Proteínas/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Transfecção , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética
19.
Clin Otolaryngol Allied Sci ; 26(4): 286-93, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11559339

RESUMO

Nasal resistance (NR) depends on the geometrical features and tortuosity of the nasal airway and on the air flow. Knowing the longitudinal distribution of cross-sectional areas (CSAs) in the nasal cavity (which can be obtained using acoustic rhinometry) and the laminar nasal resistance (obtainable by processing the rhinomanometric results), it is possible to calculate, utilizing a mathematical model elaborated on the basis of fluid dynamics, the differential nasal resistance (NRdiff) and the cumulative nasal resistance (NRcum), thus localizing the position at which the highest resistance is concentrated and the related longitudinal distribution. Using a mathematical model, we integrated the sigmoid curves DeltaP/Q of rhinomanometry with the cross-sectional areas obtained using acoustic rhinometry, thus obtaining the normal distribution of differential and cumulative nasal resistances. Afterwards, we empirically reduced the cross-sectional areas corresponding to the head, body, tail and the whole inferior turbinate, recalculating the differential and cumulative nasal resistance distribution curves. The results show that reduction of up to 50% of cross-sectional areas does not substantially affect the resistivity role of the nasal valve, while greater reductions move the highest resistivity point to an area at the junction of the body and the head of the inferior turbinate. The study of the differential nasal resistance trend curves as a function of the reduction of cross-sectional areas shows that the resistance variation of the body and the whole inferior turbinate prevail with reductions of up to 40%, while the variation of cross-sectional areas of the body bordering the inferior turbinate head is predominant with higher reductions. The cross-sectional areas of the nasal airway cavity with highest resistivity are mainly located in an anterior position, where the differential nasal resistances are higher, but there are substantial variations produced by reducing the cross-sectional area of the posterior nasal airway. A similar model can produce provisional values for the results obtainable with functional nasal surgery.


Assuntos
Resistência das Vias Respiratórias/fisiologia , Manometria/métodos , Modelos Biológicos , Cavidade Nasal/fisiologia , Acústica , Limiar Diferencial , Humanos , Nasofaringe/fisiologia , Pressão , Avaliação da Tecnologia Biomédica
20.
Blood ; 98(7): 2084-90, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11567994

RESUMO

A single dose of Mpl ligand (Mpl-L) given immediately after lethal DNA-damaging regimens prevents the death of mice. However, the mechanism of this myeloprotection is unknown. The induction of p53-dependent apoptosis in response to DNA damage signals suggests that immediate administration of Mpl-L may inhibit p53-dependent apoptosis. This hypothesis was tested by administering a single injection of pegylated murine Megakaryocyte Growth and Development Factor (PEG-rmMGDF, a truncated recombinant Mpl-L) to p53(-/-) and wild-type mice immediately after carboplatin (80 mg/kg) and 7.5 Gy total body gamma-irradiation. PEG-rmMGDF was required to prevent the death of wild-type mice, whereas p53(-/-) mice survived with or without the exogenous cytokine. The degree of platelet depression and subsequent recovery was comparable in p53(-/-) mice to wild-type animals given PEG-rmMGDF. Hence, either Mpl-L administration or p53-deficiency protected multipotent hematopoietic progenitors and committed megakaryocyte precursors. The myelosuppressive regimen induced expression of p53 and the p53 target, p21(Cipl) in wild-type bone marrow, indicating that Mpl-L acts downstream of p53 to prevent apoptosis. Constitutive expression of the proapoptotic protein Bax, was not further increased. Bax(-/-) mice survived the lethal regimen only when given PEG-rmMGDF; however, these Bax(-/-) mice showed more rapid hematopoietic recovery than did identically-treated wild-type mice. Therefore, administration of Mpl-L immediately after myelosuppressive chemotherapy or preparatory regimens for autologous bone marrow transplantation should prevent p53-dependent apoptosis, decrease myelosuppression, and reduce the need for platelet transfusions.


Assuntos
Apoptose/efeitos dos fármacos , Medula Óssea/efeitos dos fármacos , Medula Óssea/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2 , Trombopoetina/farmacologia , Proteína Supressora de Tumor p53/farmacologia , Animais , Proteínas Mutadas de Ataxia Telangiectasia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/patologia , Células da Medula Óssea/efeitos da radiação , Carboplatina/administração & dosagem , Carboplatina/intoxicação , Proteínas de Ciclo Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Proteínas de Ligação a DNA , Morte , Hematopoese/efeitos dos fármacos , Camundongos , Camundongos Knockout , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/farmacologia , Proteínas Serina-Treonina Quinases/farmacologia , Proteínas Proto-Oncogênicas/farmacologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/farmacologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/patologia , Células-Tronco/efeitos da radiação , Trombopoetina/administração & dosagem , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor , Irradiação Corporal Total/efeitos adversos , Proteína X Associada a bcl-2
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