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1.
Pneumologie ; 74(10): 678-683, 2020 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-32643764

RESUMO

Chronic granulomatous disease (CGD) should be considered as a differential diagnosis in children and adolescents with frequent infections, especially when caused by certain specific pathogens.This case report describes a 64-year-old female with multiple recurrent and complicated bronchopulmonary infections, caused by common, but also rare pathogens, autoimmune phenomena, malignancies and recurrent organizing pneumonia (OP) with granulomas. Finally, the patient was diagnosed with p47phox-deficient chronic granulomatous disease (CGD).Individuals with a primary immunodeficiency may survive multiple complications and may be diagnosed at an advanced age especially if the affected structure shows residual activity. When confronted with patients with recurrent bronchopulmonary infections, especially with certain specific rare pathogens, in combination with organizing pulmonary granulomas as well as autoimmune phenomena, CGD should be considered even in elderly patients. Delayed diagnosis significantly increases mortality and morbidity in such cases.


Assuntos
Doença Granulomatosa Crônica/diagnóstico , Pneumonia/diagnóstico , Diagnóstico Diferencial , Feminino , Doença Granulomatosa Crônica/complicações , Humanos , Infecções , Pessoa de Meia-Idade , Pneumonia/etiologia
2.
Colorectal Dis ; 19(5): O108-O114, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27992095

RESUMO

AIM: Biennial faecal occult blood testing (FOBT) is used to screen for colorectal cancer throughout the UK. Interval cancers are tumours that develop in patients between screening rounds who have had a negative FOBT. Through a multicentre study, we compared the demographics of patients with interval cancers, FOBT screen detected cancers and cancers that developed in patients who chose not to participate in the screening programme. METHOD: Five hundred and sixteen colorectal cancers were detected in the screening age group (60-74 years) population in three UK National Health Service hospitals over 2 years. One hundred and twenty seven (25%) were interval cancers, 161 (31%) were screen detected and 228 (44%) were cancers that developed in patients who had declined FOBT. The interval cancer group had a higher incidence of right-sided cancers (38% vs 29% and 24%), a higher proportion of high tumour stages (Dukes C and D) (70% vs 53% and 33%) and a shorter time from diagnosis to death (10 months vs 13 months and 24 months) compared to patients who had declined the FOBT and the FOBT screen detected cancers. Of all the patients studied, those with right-sided interval cancers had the worst outcome. CONCLUSION: A quarter of the colorectal cancers diagnosed in our study were interval cancers. Patients with right-sided interval cancers had the highest proportion of Dukes C and D tumours coupled with the shortest survival time after diagnosis compared with the other groups.


Assuntos
Neoplasias Colorretais/diagnóstico , Diagnóstico Tardio , Detecção Precoce de Câncer/efeitos adversos , Programas de Rastreamento/efeitos adversos , Sangue Oculto , Idoso , Neoplasias Colorretais/mortalidade , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Programas Nacionais de Saúde , Fatores de Tempo , Reino Unido
3.
Artigo em Alemão | MEDLINE | ID: mdl-25446311

RESUMO

BACKGROUND: Genetic aortic syndromes are autosomal-dominantly heritable aneurysms of the thoracic aorta, which carry a high risk of aortic rupture or acute thoracic aortic dissection at young age. OBJECTIVES: We introduce the reader to the principles of genetic diagnostics and the medical and surgical prevention of thoracic aortic dissection in patients with genetic aortic syndromes. METHODS: A cardiologist, a health economist, a patient representative, a heart surgeon, and a molecular geneticist teamed up to elucidate their perspective on major aspects of genetics and prevention of genetic aortic syndromes. RESULTS: Genetic aortic syndromes reflect a broad spectrum of diverse disease entities comprising the Marfan syndrome, the Loeys-Dietz syndrome or the vascular Ehlers-Danlos syndrome. The diagnosis of each respective disease entity requires combined assessment of phenotype and genotype information. A medical prevention of aortic complications such as dissection is mandatory although a curative therapy currently appears unlikely in humans. The single most important measure against acute aortic dissection is the preventive replacement of the aortic root, where valve preserving techniques appear preferable. Comprehensive prophylaxis including molecular diagnostics seem reasonable also from an economic point of view. DISCUSSION: Optimal prevention requires individualization of concepts, which entail a detailed diagnostic characterization of each specific genetic aortic syndrome including characterization of the genotype.


Assuntos
Aneurisma da Aorta Torácica/genética , Aneurisma da Aorta Torácica/prevenção & controle , Testes Genéticos/métodos , Síndrome de Marfan/genética , Síndrome de Marfan/prevenção & controle , Predisposição Genética para Doença/genética , Predisposição Genética para Doença/prevenção & controle , Humanos , Medicina de Precisão/métodos
4.
Virchows Arch ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980338

RESUMO

Fluorescence confocal microscopy (FCM) is an optical technique that uses laser light sources of different wavelengths to generate real-time images of fresh, unfixed tissue specimens. FCM allows histological evaluation of fresh tissue samples without the associated cryo artifacts after frozen sectioning. The aim of this study was to prospectively evaluate pediatric tumor specimens and assess their suitability for fresh tumor sampling. In addition, we aimed to determine whether tumor cell isolation for stable cell culture is still feasible after FCM imaging. Pediatric tumor specimens were imaged using FCM. Tumor viability and suitability for tissue sampling were evaluated and compared with H&E staining after paraffin embedding. In addition, FCM-processed and non-FCM-processed tissue samples were sent for tumor cell isolation to evaluate possible effects after FCM processing. When comparing estimated tumor cell viability using FCM and H&E, we found good to excellent correlating estimates (intraclass correlation coefficient = 0.891, p < 0.001), as well as substantial agreement in whether the tissue appeared adequate for fresh tissue collection (κ = 0.762, p < 0.001). After FCM, seven out of eight samples yielded passable cell cultures, compared to eight out of eight for non-FCM processed samples. Our study suggests that the use of FCM in tumor sampling can increase the yield of suitable fresh tumor samples by identifying viable tumor areas and ensuring that sufficient tissue remains for diagnosis. Our study also provides first evidence that the isolation and growth of tumor cells in culture are not compromised by the FCM technique.

5.
Nanotechnology ; 23(1): 015305, 2012 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-22155980

RESUMO

A novel strategy for fabricating nanoimprint templates with sub-10 nm patterns is demonstrated by combining electron beam lithography and atomic layer deposition. Nanostructures are replicated by step-and-repeat nanoimprint lithography and successfully transferred into functional material with high fidelity. The process extends the capacity of step-and-repeat nanoimprint lithography as a single digit nanofabrication method. Using the ALD process for feature shrinkage, we identify a size dependent deposition rate.

6.
Cell Death Differ ; 15(5): 820-30, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18309326

RESUMO

Primary chronic lymphocytic leukemia (CLL) cells are exquisitely sensitive to ABT-737, a small molecule BCL2-antagonist, which induces many of the classical biochemical and ultrastructural features of apoptosis, including BAX/BAK oligomerization, cytochrome c release, caspase activation and chromatin condensation. Surprisingly, ABT-737 also induces mitochondrial inner membrane permeabilization (MIMP) resulting in mitochondrial matrix swelling and rupture of the outer mitochondrial membrane (OMM), so permitting the rapid efflux of cytochrome c from mitochondrial cristae and facilitating rapid caspase activation and apoptosis. BAX and BAK appear to be involved in the OMM discontinuities as they localize to the OMM break points. Notably, ABT-737 induced mitochondrial matrix swelling and OMM discontinuities in other primary B-cell malignancies, including mantle cell, follicular and marginal zone lymphoma cells but not in several cell lines studied. Thus, we describe a new paradigm of apoptosis in primary B-cell malignancies, whereby targeting of BCL2 results in all the classical features of apoptosis together with OMM rupture independent of caspase activation. This mechanism may be far more prevalent than hitherto recognized due to the failure of most methods, used to measure apoptosis, to recognize such a mechanism.


Assuntos
Apoptose/efeitos dos fármacos , Compostos de Bifenilo/farmacologia , Leucemia Linfocítica Crônica de Células B/metabolismo , Membranas Mitocondriais/efeitos dos fármacos , Nitrofenóis/farmacologia , Sulfonamidas/farmacologia , Adulto , Clorometilcetonas de Aminoácidos/metabolismo , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Linfócitos B/patologia , Linhagem Celular Tumoral , Inibidores de Cisteína Proteinase/metabolismo , Relação Dose-Resposta a Droga , Humanos , Leucemia Linfocítica Crônica de Células B/patologia , Membranas Mitocondriais/ultraestrutura , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo
7.
Oncogene ; 26(2): 248-57, 2007 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-16832350

RESUMO

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a promising candidate for cancer therapy because of its relative tumor selectivity. However, many cancers including pancreatic cancer remain resistant towards TRAIL. To develop TRAIL for cancer therapy of pancreatic carcinoma, it will therefore be pivotal to elucidate the molecular mechanisms of TRAIL resistance. Here, we identify X-linked inhibitor of apoptosis (XIAP) as a regulator of TRAIL sensitivity in pancreatic carcinoma cells. Full activation of effector caspases, loss of mitochondrial membrane potential and cytochrome c release following TRAIL treatment were markedly impaired in pancreatic carcinoma cell lines, which poorly responded to TRAIL (PaTuII, PancTu1, ASPC1, DanG), compared to TRAIL-sensitive Colo357 pancreatic carcinoma cells. Stable downregulation of XIAP by RNA interference significantly reduced survival and enhanced TRAIL-induced apoptosis in pancreatic carcinoma cells. Also, downregulation of XIAP significantly increased CD95-induced cell death. Importantly, knockdown of XIAP strongly inhibited clonogenicity of pancreatic cancer cells treated with TRAIL indicating that XIAP promotes clonogenic survival of pancreatic carcinoma cells. Thus, our findings for the first time indicate that targeting XIAP represents a promising strategy to enhance the antitumor activity of TRAIL in pancreatic cancer, which has important clinical implications.


Assuntos
Apoptose , Neoplasias Pancreáticas/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Caspases Efetoras/metabolismo , Citocromos c/metabolismo , Humanos , Ligantes , Potencial da Membrana Mitocondrial , Neoplasias Pancreáticas/patologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Retroviridae/genética , Transfecção , Células Tumorais Cultivadas , Ensaio Tumoral de Célula-Tronco , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/antagonistas & inibidores , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética
8.
AIDS ; 7(9): 1247-54, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8216983

RESUMO

OBJECTIVE: Since heterosexual transmission of HIV in the United States is occurring at an increasing rate, especially among black and Hispanic couples and those in which one member has a history of intravenous drug use, we sought to study the heterosexual transmission of HIV in couples. DESIGN: Multiple logistic regression analysis of risks for HIV infection in female partners. METHODS: We enrolled 158 non-intravenous drug user (IVDU) steady heterosexual partners of HIV-infected individuals (indexes) in this study. Of these, 93% were women, 54% were Hispanic whites, 23% were black and 65.6% were partners of IVDU. RESULTS: In a multiple logistic regression analysis of risks for HIV infection in female partners, the strongest predictors of transmission were AIDS or AIDS-related complex (ARC) in the index [adjusted odds ratios (OR), 16.81; P < 0.001 and 12.53; P = 0.003, respectively], a history of anal intercourse (adjusted OR, 10.81; P < 0.001) and bleeding as a result of intercourse (adjusted OR, 4.90; P < 0.05). Female-to-male transmission was detected in seven out of 11 couples at risk. Ethnicity, number of episodes of vaginal intercourse, number of other sexual partners and history of sexually transmitted infections were not significantly associated with transmission to women. CONCLUSION: Our study demonstrates that health of the index, anal intercourse and bleeding as a result of intercourse are the major determinants of sexual transmission of HIV to women in couples.


Assuntos
Infecções por HIV/transmissão , Parceiros Sexuais , Adolescente , Adulto , Fatores Etários , Idoso , Estudos de Coortes , Dispositivos Anticoncepcionais Masculinos/estatística & dados numéricos , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/etnologia , Humanos , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque/epidemiologia , Grupos Raciais , Análise de Regressão , Comportamento Sexual , Infecções Sexualmente Transmissíveis/epidemiologia , Transtornos Relacionados ao Uso de Substâncias
9.
AIDS Res Hum Retroviruses ; 8(8): 1355-9, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1466956

RESUMO

A comparison of the proliferative responses of lymphocytes to human immunodeficiency virus (HIV) antigens from long-term, seronegative heterosexual partners of HIV-infected subjects, from normal unexposed controls and from healthy seropositive heterosexual partners or seropositive, asymptomatic men, reveals that lymphocytes from healthy seropositive individuals with strong proliferative responses to recall, microbial antigens respond only minimally to HIV proteins or envelope peptides, and that even these low responses do not occur in all individuals. If the frequency of responses to several HIV antigens are analyzed, lymphocytes from both HIV-exposed seropositive and seronegative partners of infected individuals proliferate to HIV antigens to a greater degree than lymphocytes from unexposed, normal control individuals. Although lymphocytes from seropositive partners proliferate to a greater degree than those from seronegative partners, the latter are more similar to seropositive partners than they are to normal controls. This observation suggests that these seronegative partners may have become sensitized to HIV antigens through sexual exposure but without infection, and/or that the presence or development of these small immune responses in some individuals might be associated with a failure to become infected.


Assuntos
Antígenos HIV/imunologia , Infecções por HIV , Soropositividade para HIV/imunologia , Ativação Linfocitária , Parceiros Sexuais , Feminino , Produtos do Gene gag/imunologia , Proteína gp120 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , Infecções por HIV/transmissão , Humanos , Imunidade Inata/imunologia , Memória Imunológica , Masculino , Fragmentos de Peptídeos/imunologia , Comportamento Sexual
10.
J Infect ; 20(2): 129-33, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2319145

RESUMO

A case of infection involving a prosthetic joint in a patient with adult Still's Disease is described. The causative organism was a strain of Bacteroides fragilis which was resistant to metronidazole. The rarity of this occurrence is emphasised. Diagnostic difficulties which arose are described and the problems encountered with therapy discussed.


Assuntos
Infecções por Bacteroides/tratamento farmacológico , Bacteroides fragilis/efeitos dos fármacos , Prótese de Quadril , Metronidazol/uso terapêutico , Administração Oral , Adulto , Animais , Resistência Microbiana a Medicamentos , Humanos , Injeções Intravenosas , Masculino , Metronidazol/administração & dosagem , Metronidazol/efeitos adversos
11.
Laryngoscope ; 92(1): 76-9, 1982 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7162302

RESUMO

Careful presurgical otologic assessment of the contralateral ear in acoustic tumor patients is essential, not only to establish baseline data but more importantly to resolve the intense patient anxiety that arises almost immediately when the diagnosis is presented. Any subsequent reduction in hearing acuity in the contralateral ear after the tumor ear has been deafened, poses serious psychological, socio-economic and medical problems. Three detailed case reports of sudden hearing loss in the contralateral ear of postoperative acoustic tumor patients are presented. The lesion sites include: the middle ear, cochlear, and retrocochlear. In each case, hearing returned to its previous or near-previous levels. Allergic factors were implicated in two cases.


Assuntos
Neoplasias dos Nervos Cranianos/cirurgia , Perda Auditiva Condutiva/etiologia , Perda Auditiva Neurossensorial/etiologia , Perda Auditiva/etiologia , Doenças do Nervo Vestibulococlear/cirurgia , Adulto , Neoplasias dos Nervos Cranianos/complicações , Hipersensibilidade a Drogas/complicações , Feminino , Hipersensibilidade Alimentar/complicações , Humanos , Masculino , Complicações Pós-Operatórias , Doenças do Nervo Vestibulococlear/complicações
12.
Laryngoscope ; 91(11): 1792-800, 1981 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7300530

RESUMO

Hearing conservation in acoustic tumor surgery is an admirable goal and a logical extension of micro neurotologic surgery, but ideal candidates for conservation are few, and attempts to preserve hearing in those few fail in about half of all cases. Conserved hearing most often falls far beyond a range that will provide binaural function and is, therefore, of questionable use. The problem of hearing conservation in acoustic tumor surgery is rationally approached based upon the implications of the total presurgical overview, particularly with reference to age, general health, tumor size, and especially hearing in the tumor ear, the contralateral ear, and interaural relationships. Technical considerations, the morbidity and mortality, and, finally, probability factors are reviewed from the literature, The patient's consideration regarding potentials for hearing conservation, his need for conservation, and alternative options are discussed. Rehabilitative options for unilateral hearing impairment are discussed. A review of the amplification requirements of 45 acoustic tumor patients - 5 or more years postoperative - indicated that three-quarters had normal hearing in the contralateral ear, 24% of whom required CROS amplification; 67% of the remaining quarter had mild to moderate hearing losses and were effectively wearing BiCROS aids. None were rehabilitated with monaural aids; 20% of the entire group studied had demonstrated some degree of additional hearing loss in the non-tumor ear since surgery.


Assuntos
Auxiliares de Audição , Perda Auditiva/reabilitação , Neuroma Acústico/complicações , Amplificadores Eletrônicos , Perda Auditiva/etiologia , Testes Auditivos , Humanos , Métodos , Neuroma Acústico/cirurgia , Risco , Revelação da Verdade
13.
Int J Gynaecol Obstet ; 71(2): 135-9, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11064010

RESUMO

OBJECTIVES: To evaluate the safety and effectiveness of hysterectomy vs. cone biopsy in HIV seropositive patients with carcinoma in situ of the cervix (CIS). METHODS: We performed a retrospective case-control study of all HIV seropositive patients diagnosed with carcinoma in situ of the cervix from 1989 to 1995. A control group of HIV(-) women with CIS was also ascertained matched for date of diagnosis of CIS, race and age. RESULTS: There were 439 patients with CIS, of which 45 were HIV seropositive (10.3%). Nine were treated by hysterectomy, 30 by cone biopsy, and six remained untreated. Overall, 63% of HIV(+) patients did not receive any follow-up Pap smear (44% of hysterectomy patients, 50% of cone biopsy patients, and 83% of untreated patients; chi(2) P=0.41). According to Pap smear results, 67% (10/15) cone biopsy patients and 60% (3/5) hysterectomy patients had an abnormal Pap smear after treatment (P=0.9). Median time to recurrence was 12 months in hysterectomy patients vs. 14 months in cone biopsy patients. Deaths occurred in 22% of hysterectomy patients, 17% of cone biopsy patients, and 50% of untreated patients, none due to cervical cancer. Median time to death from presentation was 27.5 months for hysterectomy patients, 11 months for cone biopsy patients, and 7 months for untreated patients (P<0.05). There were no complications in the hysterectomy group, however, two patients were readmitted after cone biopsy for bleeding. When compared to HIV(-) women with CIS, HIV(+) patients were more likely to be treated by hysterectomy (chi(2) P=0.01). CONCLUSION: All patients diagnosed with CIS should be counseled regarding HIV prevention and testing because of a significant seropositive rate. Compliance with gynecologic follow-up is very poor in this patient population. Special efforts should be made to enhance compliance. Cone biopsy and hysterectomy appear to be equally safe and effective in the treatment of CIS. CIS in HIV patients is a poor prognostic indicator for death from any cause.


Assuntos
Carcinoma in Situ/cirurgia , Colo do Útero/patologia , Conização , Infecções por HIV/complicações , Histerectomia , Neoplasias do Colo do Útero/cirurgia , Adolescente , Adulto , Carcinoma in Situ/complicações , Carcinoma in Situ/mortalidade , Carcinoma in Situ/patologia , Estudos de Casos e Controles , Colo do Útero/cirurgia , Intervalo Livre de Doença , Eletrocirurgia , Feminino , Humanos , Prontuários Médicos , New York/epidemiologia , Teste de Papanicolaou , Cooperação do Paciente , Estudos Retrospectivos , Análise de Sobrevida , Neoplasias do Colo do Útero/complicações , Neoplasias do Colo do Útero/mortalidade , Neoplasias do Colo do Útero/patologia , Esfregaço Vaginal
14.
Res Vet Sci ; 44(3): 335-7, 1988 May.
Artigo em Inglês | MEDLINE | ID: mdl-3406529

RESUMO

Oxytetracycline, administered at 40 mg kg-1 by intravenous injection, was used as part of the treatment of three female red-necked wallabies, Macropus rufogriseus, with suspected Fusobacterium necrophorum infections. The plasma concentrations of this drug in blood samples collected at intervals up to 24 hours after administration were measured using a biological assay. The pattern of decline in plasma oxytetracycline concentration with time was consistent with a two-compartment model. The half-life of the elimination phase was calculated to be 11.4 hours and the apparent volume of distribution was found to be 2.041 litres kg-1. These results provide a basis for devising appropriate oxytetracycline dosage regimes for the species.


Assuntos
Infecções por Fusobacterium/veterinária , Macropodidae/microbiologia , Marsupiais/microbiologia , Oxitetraciclina/farmacocinética , Animais , Feminino , Infecções por Fusobacterium/tratamento farmacológico , Fusobacterium necrophorum , Oxitetraciclina/administração & dosagem , Oxitetraciclina/sangue , Oxitetraciclina/uso terapêutico
15.
Cell Death Differ ; 20(11): 1475-84, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23832116

RESUMO

High levels of BCL-2 family proteins are implicated in a failed/ineffective apoptotic programme, often resulting in diseases, including cancer. Owing to their potential as drug targets in cancer therapy, several inhibitors of BCL-2 family proteins have been developed. These primarily target specific members of the BCL-2 family, particularly BCL-2 and BCL-XL but are ineffective against MCL-1. Major efforts have been invested in developing inhibitors of MCL-1, which is commonly amplified in human tumours and associated with tumour relapse and chemoresistance. In this report, the specificity of several BCL-2 family inhibitors (ABT-263, UCB-1350883, apogossypol and BH3I-1) was investigated and compared with putative MCL-1 inhibitors designed to exhibit improved or selective binding affinities for MCL-1 (TW-37, BI97C1, BI97C10, BI112D1, compounds 6 and 7, and MCL-1 inhibitor molecule (MIM-1)). ABT-263, BI97C1, BI112D1, MIM-1 and TW-37 exhibited specificity in inducing apoptosis in a Bax/Bak- and caspase-9-dependent manner, whereas the other agents showed no killing activity, or little or no specificity. Of these inhibitors, only ABT-263 and UCB-1350883 induced apoptosis in a BCL-2- or BCL-XL-dependent system. In cells that depend on MCL-1 for survival, ABT-263 and TW-37 induced extensive apoptosis, suggesting that at high concentrations these inhibitors have the propensity to inhibit MCL-1 in a cellular context. TW-37 induced apoptosis, assessed by chromatin condensation, caspase processing and phosphatidylserine externalisation, in a BAK-dependent manner and in cells that require MCL-1 for survival. TW-37-mediated apoptosis was also partly dependent on NOXA, suggesting that derivatives of TW-37, if engineered to exhibit better selectivity and efficacy at low nanomolar concentrations, may provide useful lead compounds for further synthetic programmes. Expanded medicinal chemistry iteration, as performed for the ABT series, may likewise improve the potency and specificity of the evaluated MCL-1 inhibitors.


Assuntos
Compostos de Anilina/farmacologia , Benzamidas/farmacologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Sulfonamidas/farmacologia , Sulfonas/farmacologia , Apoptose/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Humanos , Células Jurkat , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteína X Associada a bcl-2/metabolismo
16.
Cell Death Differ ; 19(1): 67-74, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22075983

RESUMO

B-cell lymphoma 2 (BCL2) proteins are important cell death regulators, whose main function is to control the release of cytochrome c from mitochondria in the intrinsic apoptotic pathway. They comprise both pro- and anti-apoptotic proteins, which interact in various ways to induce or prevent pore formation in the outer mitochondrial membrane. Due to their central function in the apoptotic machinery, BCL2 proteins are often deregulated in cancer. To this end, many anti-apoptotic BCL2 proteins have been identified as important cellular oncogenes and attractive targets for anti-cancer therapy. In this review, the existing knowledge on B-cell lymphoma 2-related protein A1 (BCL2A1)/Bcl-2-related gene expressed in fetal liver (Bfl-1), one of the less extensively studied anti-apoptotic BCL2 proteins, is summarized. BCL2A1 is a highly regulated nuclear factor κB (NF-κB) target gene that exerts important pro-survival functions. In a physiological context, BCL2A1 is mainly expressed in the hematopoietic system, where it facilitates survival of selected leukocytes subsets and inflammation. However, BCL2A1 is overexpressed in a variety of cancer cells, including hematological malignancies and solid tumors, and may contribute to tumor progression. Therefore, the development of small molecule inhibitors of BCL2A1 may be a promising approach mainly to sensitize tumor cells for apoptosis and thus improve the efficiency of anti-cancer therapy.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Apoptose , Neoplasias/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sequência de Aminoácidos , Animais , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Proteínas Reguladoras de Apoptose/genética , Regulação da Expressão Gênica , Humanos , Camundongos , Antígenos de Histocompatibilidade Menor , Dados de Sequência Molecular , NF-kappa B/metabolismo , Neoplasias/tratamento farmacológico , Ligação Proteica , Conformação Proteica , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/genética
19.
Cell Death Differ ; 16(3): 360-7, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18806758

RESUMO

Despite tremendous advances over the last 15 years in understanding fundamental mechanisms of apoptosis, this has failed to translate into improved cancer therapy for patients. However, there may now be light at the end of this long tunnel. Antiapoptotic Bcl-2 family members may be divided into two subclasses, one comprising Bcl-2, Bcl-X(L) and Bcl-w and the other Mcl-1 and Bcl2A1. Neutralization of both subclasses is required for apoptosis induction. Solution of the structure of antiapoptotic Bcl-2 family proteins has led to the design of novel small molecule inhibitors. Although many such molecules have been synthesized, rigorous verification of their specificity has often been lacking. Further studies have revealed that many putative Bcl-2 inhibitors are not specific and have other cellular targets, resulting in non-mechanism based toxicity. Two notable exceptions are ABT-737 and a related orally active derivative, ABT-263, which bind with high affinity to Bcl-2, Bcl-X(L) and Bcl-w and may prove to be useful tools for mechanistic studies. ABT-263 is in early clinical trials in lymphoid malignancies, small-cell lung cancer and chronic lymphocytic leukemia, and some patients have shown promising results. In in vitro studies, primary cells from patients with various B-cell malignancies are exquisitely sensitive to ABT-737, exhibiting novel morphological features of apoptosis including marked outer mitochondrial membrane rupture.


Assuntos
Compostos de Anilina , Apoptose/fisiologia , Compostos de Bifenilo , Neoplasias/tratamento farmacológico , Nitrofenóis , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Sulfonamidas , Compostos de Anilina/química , Compostos de Anilina/uso terapêutico , Compostos de Bifenilo/química , Compostos de Bifenilo/uso terapêutico , Células Cultivadas , Humanos , Linfoma de Célula do Manto/metabolismo , Linfoma de Célula do Manto/patologia , Estrutura Molecular , Neoplasias/metabolismo , Nitrofenóis/química , Nitrofenóis/uso terapêutico , Piperazinas/química , Piperazinas/uso terapêutico , Proteínas Proto-Oncogênicas c-bcl-2/química , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sulfonamidas/química , Sulfonamidas/uso terapêutico
20.
Cell Death Differ ; 16(7): 1030-9, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19390557

RESUMO

Several inhibitors of BCL2 proteins have been identified that induce apoptosis in a variety of tumor cells, indicating their potential in cancer therapy. We investigated the specificity of six putative BCL2 inhibitors (obatoclax, gossypol, apogossypol, EM20-25, chelerythrine and ABT-737). Using cells deficient either for Bax/Bak or caspase-9, we found that only ABT-737 specifically targeted BCL2 proteins and induced apoptosis by activation of caspase-9, as only ABT-737 induced apoptosis was completely inhibited in cells deficient for Bax/Bak or caspase-9. Our data show that only ABT-737 is a specific BCL2 inhibitor and all other compounds investigated were not specific for BCL2 proteins. Furthermore, investigations of the effects of these compounds in primary chronic lymphocytic leukemic cells showed that all compounds induced certain biochemical hallmarks of apoptosis, such as release of cytochrome c and caspase cleavage. However, they all caused strikingly different ultrastructural changes. ABT-737 induced all the characteristic ultrastructural changes of apoptosis together with early rupture of the outer mitochondrial membrane, whereas obatoclax, chlelerythrine and gossypol induced pronounced mitochondrial swelling with formation of phospholipid inclusions. Therefore, we conclude that biochemical measurements used earlier to define apoptosis like mitochondrial release of cytochrome c and caspase cleavage, are insufficient to distinguish between classic apoptosis and other forms of cell death.


Assuntos
Antineoplásicos/farmacologia , Apoptose , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Animais , Compostos de Bifenilo/farmacologia , Caspase 9/genética , Caspase 9/metabolismo , Morte Celular , Linhagem Celular , Linhagem Celular Tumoral , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/ultraestrutura , Técnicas de Silenciamento de Genes , Humanos , Células Jurkat , Camundongos , Microscopia Eletrônica de Transmissão , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Nitrofenóis/farmacologia , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sulfonamidas/farmacologia , Proteína Killer-Antagonista Homóloga a bcl-2/genética , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
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