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1.
N Engl J Med ; 374(4): 311-22, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26639348

RESUMO

BACKGROUND: New treatments have improved outcomes for patients with relapsed chronic lymphocytic leukemia (CLL), but complete remissions remain uncommon. Venetoclax has a distinct mechanism of action; it targets BCL2, a protein central to the survival of CLL cells. METHODS: We conducted a phase 1 dose-escalation study of daily oral venetoclax in patients with relapsed or refractory CLL or small lymphocytic lymphoma (SLL) to assess safety, pharmacokinetic profile, and efficacy. In the dose-escalation phase, 56 patients received active treatment in one of eight dose groups that ranged from 150 to 1200 mg per day. In an expansion cohort, 60 additional patients were treated with a weekly stepwise ramp-up in doses as high as 400 mg per day. RESULTS: The majority of the study patients had received multiple previous treatments, and 89% had poor prognostic clinical or genetic features. Venetoclax was active at all dose levels. Clinical tumor lysis syndrome occurred in 3 of 56 patients in the dose-escalation cohort, with one death. After adjustments to the dose-escalation schedule, clinical tumor lysis syndrome did not occur in any of the 60 patients in the expansion cohort. Other toxic effects included mild diarrhea (in 52% of the patients), upper respiratory tract infection (in 48%), nausea (in 47%), and grade 3 or 4 neutropenia (in 41%). A maximum tolerated dose was not identified. Among the 116 patients who received venetoclax, 92 (79%) had a response. Response rates ranged from 71 to 79% among patients in subgroups with an adverse prognosis, including those with resistance to fludarabine, those with chromosome 17p deletions (deletion 17p CLL), and those with unmutated IGHV. Complete remissions occurred in 20% of the patients, including 5% who had no minimal residual disease on flow cytometry. The 15-month progression-free survival estimate for the 400-mg dose groups was 69%. CONCLUSIONS: Selective targeting of BCL2 with venetoclax had a manageable safety profile and induced substantial responses in patients with relapsed CLL or SLL, including those with poor prognostic features. (Funded by AbbVie and Genentech; ClinicalTrials.gov number, NCT01328626.).


Assuntos
Antineoplásicos/administração & dosagem , Compostos Bicíclicos Heterocíclicos com Pontes/administração & dosagem , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Sulfonamidas/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Compostos Bicíclicos Heterocíclicos com Pontes/efeitos adversos , Compostos Bicíclicos Heterocíclicos com Pontes/farmacocinética , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Indução de Remissão , Sulfonamidas/efeitos adversos , Sulfonamidas/farmacocinética , Síndrome de Lise Tumoral/etiologia
2.
FASEB J ; 31(1): 192-202, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27682206

RESUMO

Although α6-contaning (α6*) nicotinic acetylcholine receptors (nAChRs) are densely expressed in the visual system, their role is not well known. We have characterized a family of toxins that are antagonists for α6ß2* receptors and used one of these [RDP-MII(E11R)] to localize α6* nAChRs and investigate their impact on retinal function in adult Long-Evans rats. The α6*nAChRs in retinal tissue were localized using either a fluorescently tagged [RDP-MII(E11R)] or anti-α6-specific antibodies and found to be predominantly at the level of the ganglion cell layer. After intraocular injection of RDP-MII(E11R) in one eye and vehicle or inactive MII in contralateral eyes as controls, we recorded flash electroretinograms (F-ERGs), pattern ERGs (P-ERGs), and cortical visual-evoked potential (VEPs). There was no significant difference in F-ERG between the RDP-MII(E11R)-treated and control eyes. In contrast, P-ERG response amplitude was significantly reduced in the RDP-MII(E11R)-injected eye. Blocking α6* nAChRs at retinal level also decreased the VEP amplitude recorded in the visual cortex contralateral to the injected eye. Because both the cortical and inner retina output were affected by RDP-MII(E11R), whereas photoreceptor output was preserved, we conclude that the reduced visual response was due to an alteration in the function of α6* nAChRs present in the ganglion cell layer.-Barloscio, D., Cerri, E., Domenici, L., Longhi, R., Dallanoce, C., Moretti, M., Vilella, A., Zoli, M., Gotti, C., and Origlia, N. In vivo study of the role of α6-containing nicotinic acetylcholine receptor in retinal function using subtype-specific RDP-MII(E11R) toxin.


Assuntos
Conotoxinas/toxicidade , Antagonistas Nicotínicos/toxicidade , Receptores Nicotínicos/metabolismo , Retina/fisiologia , Animais , Córtex Cerebral/fisiologia , Conotoxinas/administração & dosagem , Potenciais Evocados Visuais/efeitos dos fármacos , Potenciais Evocados Visuais/fisiologia , Masculino , Antagonistas Nicotínicos/administração & dosagem , Ratos , Ratos Long-Evans
3.
Lancet Oncol ; 18(2): 230-240, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28089635

RESUMO

BACKGROUND: Selective BCL2 inhibition with venetoclax has substantial activity in patients with relapsed or refractory chronic lymphocytic leukaemia. Combination therapy with rituximab enhanced activity in preclinical models. The aim of this study was to assess the safety, pharmacokinetics, and activity of venetoclax in combination with rituximab. METHODS: Adult patients with relapsed or refractory chronic lymphocytic leukaemia (according to the 2008 Modified International Workshop on CLL guidelines) or small lymphocytic lymphoma were eligible for this phase 1b, dose-escalation trial. The primary outcomes were to assess the safety profile, to determine the maximum tolerated dose, and to establish the recommended phase 2 dose of venetoclax when given in combination with rituximab. Secondary outcomes were to assess the pharmacokinetic profile and analyse efficacy, including overall response, duration of response, and time to tumour progression. Minimal residual disease was a protocol-specified exploratory objective. Central review of the endpoints was not done. Venetoclax was dosed daily using a stepwise escalation to target doses (200-600 mg) and then monthly rituximab commenced (375 mg/m2 in month 1 and 500 mg/m2 in months 2-6). Adverse events were graded according to the National Cancer Institute Common Terminology Criteria for adverse events version 4.0. Protocol-guided drug cessation was allowed for patients who achieved complete response (including complete response with incomplete marrow recovery) or negative bone marrow minimal residual disease. Analyses were done per protocol for all patients who commenced drug and included all patients who received at least one dose of venetoclax. Data were pooled across dose cohorts. Patients are still receiving therapy and follow-up is ongoing. The trial is registered at ClinicalTrials.gov, number NCT01682616. FINDINGS: Between Aug 6, 2012, and May 28, 2014, we enrolled 49 patients. Common grade 1-2 toxicities included upper respiratory tract infections (in 28 [57%] of 49 patients), diarrhoea (27 [55%]), and nausea (25 [51%]). Grade 3-4 adverse events occurred in 37 (76%) of 49 patients; most common were neutropenia (26 [53%]), thrombocytopenia (eight [16%]), anaemia (seven [14%]), febrile neutropenia (six [12%]), and leucopenia (six [12%]). The most common serious adverse events were pyrexia (six [12%]), febrile neutropenia (five [10%]), lower respiratory tract infection, and pneumonia (each three [6%]). Clinical tumour lysis syndrome occurred in two patients (resulting in one death) who initiated venetoclax at 50 mg. After enhancing tumour lysis syndrome prophylaxis measures and commencing venetoclax at 20 mg, clinical tumour lysis syndrome did not occur. The maximum tolerated dose was not identified; the recommended phase 2 dose of venetoclax in combination with rituximab was 400 mg. Overall, 42 (86%) of 49 patients achieved a response, including a complete response in 25 (51%) of 49 patients. 2 year estimates for progression-free survival and ongoing response were 82% (95% CI 66-91) and 89% (95% CI 72-96), respectively. Negative marrow minimal residual disease was attained in 20 (80%) of 25 complete responders and 28 (57%) of 49 patients overall. 13 responders ceased all therapy; among these all 11 minimal residual disease-negative responders remain progression-free off therapy. Two with minimal residual disease-positive complete response progressed after 24 months off therapy and re-attained response after re-initiation of venetoclax. INTERPRETATION: A substantial proportion of patients achieved an overall response with the combination of venetoclax and rituximab including 25 (51%) of 49 patients who achieved a complete response and 28 (57%) of 49 patients who achieved negative marrow minimal residual disease with acceptable safety. The depth and durability of responses observed with the combination offers an attractive potential treatment option for patients with relapsed or refractory chronic lymphocytic leukaemia and could allow some patients to maintain response after discontinuing therapy, a strategy that warrants further investigation in randomised studies. FUNDING: AbbVie Inc and Genentech Inc.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Terapia de Salvação , Adulto , Idoso , Idoso de 80 Anos ou mais , Compostos Bicíclicos Heterocíclicos com Pontes/administração & dosagem , Estudos de Coortes , Feminino , Seguimentos , Humanos , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia/patologia , Prognóstico , Indução de Remissão , Rituximab/administração & dosagem , Sulfonamidas/administração & dosagem , Taxa de Sobrevida
4.
Oncologist ; 22(11): 1283-1291, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28851760

RESUMO

Tumor lysis syndrome (TLS) is an uncommon but potentially life-threatening complication associated with the treatment of some cancers. If left untreated, TLS may result in acute renal failure, cardiac dysrhythmia, neurologic complications, seizures, or death. Tumor lysis syndrome is most commonly observed in patients with hematologic malignancies with a high proliferation rate undergoing treatment with very effective therapies. In chronic lymphocytic leukemia (CLL), historically, TLS has been observed less often, owing to a low proliferation rate and slow response to chemotherapy. New targeted therapies have recently been approved in the treatment of CLL, including the oral kinase inhibitors, idelalisib and ibrutinib, and the B-cell lymphoma-2 protein inhibitor, venetoclax. Several others are also under development, and combination strategies of these agents are being explored. This review examines the diagnosis, prevention, and management of TLS and summarizes the TLS experience in CLL clinical trials with newer targeted agents. Overall, the risk of TLS is small, but the consequences may be fatal; therefore, patients should be monitored carefully. Therapies capable of eliciting rapid response and combination regimens are increasingly being evaluated for treatment of CLL, which may pose a higher risk of TLS. For optimal management, patients at risk for TLS require prophylaxis and close monitoring with appropriate tests and appropriate management to correct laboratory abnormalities, which allows for safe and effective disease control. IMPLICATIONS FOR PRACTICE: Tumor lysis syndrome (TLS) is a potentially fatal condition observed with hematologic malignancies, caused by release of cellular components in the bloodstream from rapidly dying tumor cells. The frequency and severity of TLS is partly dependent upon the biology of the disease and type of therapy administered. Novel targeted agents highly effective at inducing rapid cell death in chronic lymphocytic leukemia (CLL) may pose a risk for TLS in patients with tumors characterized by rapid growth, high tumor burden, and/or high sensitivity to treatment. In this review, prevention strategies and management of patients with CLL who develop TLS are described.


Assuntos
Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Síndrome de Lise Tumoral/tratamento farmacológico , Antineoplásicos/uso terapêutico , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Gerenciamento Clínico , Humanos , Leucemia Linfocítica Crônica de Células B/complicações , Leucemia Linfocítica Crônica de Células B/prevenção & controle , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Purinas/uso terapêutico , Quinazolinonas/uso terapêutico , Fatores de Risco , Sulfonamidas/uso terapêutico , Carga Tumoral , Síndrome de Lise Tumoral/complicações , Síndrome de Lise Tumoral/diagnóstico , Síndrome de Lise Tumoral/prevenção & controle
5.
Lancet Oncol ; 17(6): 768-778, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27178240

RESUMO

BACKGROUND: Deletion of chromosome 17p (del[17p]) in patients with chronic lymphocytic leukaemia confers very poor prognosis when treated with standard chemo-immunotherapy. Venetoclax is an oral small-molecule BCL2 inhibitor that induces chronic lymphocytic leukaemia cell apoptosis. In a previous first-in-human study of venetoclax, 77% of patients with relapsed or refractory chronic lymphocytic leukaemia achieved an overall response. Here we aimed to assess the activity and safety of venetoclax monotherapy in patients with relapsed or refractory del(17p) chronic lymphocytic leukaemia. METHODS: In this phase 2, single-arm, multicentre study, we recruited patients aged 18 years and older with del(17p) relapsed or refractory chronic lymphocytic leukaemia (as defined by 2008 Modified International Workshop on Chronic Lymphocytic Leukemia guidelines) from 31 centres in the USA, Canada, UK, Germany, Poland, and Australia. Patients started once daily venetoclax with a weekly dose ramp-up schedule (20, 50, 100, 200, 400 mg) over 4-5 weeks. Patients were then given daily 400 mg continuous dosing until disease progression or discontinuation for another reason. The primary endpoint was the proportion of patients achieving an overall response, assessed by an independent review committee. Activity and safety analyses included all patients who received at least one dose of study drug (per protocol). This study is registered with ClinicalTrials.gov, number NCT01889186. Follow-up is ongoing, and patients are still receiving treatment. FINDINGS: Between May 27, 2013, and June 27, 2014, 107 patients were enrolled into the study. At a median follow-up of 12·1 months (IQR 10·1-14·2), an overall response by independent review was achieved in 85 (79·4%; 95% CI 70·5-86·6) of 107 patients. The most common grade 3-4 adverse events were neutropenia (43 [40%]), infection (21 [20%]), anaemia (19 [18%]), and thrombocytopenia (16 [15%]). Serious adverse events occurred in 59 (55%) patients, irrespective of their relationship to treatment, with the most common (≥5% of patients) being pyrexia and autoimmune haemolytic anaemia (seven [7%] each), pneumonia (six [6%]), and febrile neutropenia (five [5%]). 11 patients died in the study within 30 days of the last dose of venetoclax; seven due to disease progression and four from an adverse event (none assessed as treatment related). INTERPRETATION: Results of this trial show that venetoclax monotherapy is active and well tolerated in patients with relapsed or refractory del(17p) chronic lymphocytic leukaemia, providing a new therapeutic option for this very poor prognosis population. Additionally, in view of the distinct mechanism-of-action of venetoclax, combinations or sequencing with other novel targeted agents should be investigated to further advance treatment of del(17p) chronic lymphocytic leukaemia. FUNDING: AbbVie and Genentech.


Assuntos
Antineoplásicos/uso terapêutico , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Deleção Cromossômica , Cromossomos Humanos Par 17/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Terapia de Salvação , Sulfonamidas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida
6.
Sci Rep ; 10(1): 18361, 2020 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-33110151

RESUMO

Creatine Transporter Deficiency (CTD) is an inborn error of metabolism presenting with intellectual disability, behavioral disturbances and epilepsy. There is currently no cure for this disorder. Here, we employed novel biomarkers for monitoring brain function, together with well-established behavioral readouts for CTD mice, to longitudinally study the therapeutic efficacy of cyclocreatine (cCr) at the preclinical level. Our results show that cCr treatment is able to partially correct hemodynamic responses and EEG abnormalities, improve cognitive deficits, revert autistic-like behaviors and protect against seizures. This study provides encouraging data to support the potential therapeutic benefit of cyclocreatine or other chemically modified lipophilic analogs of Cr.


Assuntos
Transtorno Autístico/etiologia , Encefalopatias Metabólicas Congênitas/tratamento farmacológico , Transtornos Cognitivos/etiologia , Creatina/deficiência , Creatinina/análogos & derivados , Epilepsia/etiologia , Deficiência Intelectual Ligada ao Cromossomo X/tratamento farmacológico , Proteínas da Membrana Plasmática de Transporte de Neurotransmissores/deficiência , Animais , Transtorno Autístico/tratamento farmacológico , Barreira Hematoencefálica , Encefalopatias Metabólicas Congênitas/complicações , Circulação Cerebrovascular/efeitos dos fármacos , Transtornos Cognitivos/tratamento farmacológico , Creatinina/uso terapêutico , Modelos Animais de Doenças , Eletroencefalografia , Epilepsia/tratamento farmacológico , Hemodinâmica/efeitos dos fármacos , Masculino , Deficiência Intelectual Ligada ao Cromossomo X/complicações , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Convulsões/tratamento farmacológico , Convulsões/etiologia , Comportamento Estereotipado/efeitos dos fármacos
7.
Methods Mol Biol ; 1695: 69-80, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29190019

RESUMO

Visual responses to gratings alternating in contrast have been studied in humans and several mammalian species. Previous evidence from human patients and animal models of neurodegeneration has highlighted the importance to record simultaneously the pattern electroretinogram (P-ERG) and visual evoked cortical potentials (VEPs) to investigate retinal and post-retinal sites of neurodegeneration.In view of the increasing importance of research on experimental models of neurodegenerative diseases, we present here the parametric properties of visual evoked responses in animal models of glaucoma and Alzheimer's disease. Glaucoma and Alzheimer's disease (AD) are two distinct multifactorial neurodegenerative and progressive diseases, primarily affecting the elderly.


Assuntos
Doença de Alzheimer/fisiopatologia , Glaucoma/fisiopatologia , Retina/fisiopatologia , Animais , Modelos Animais de Doenças , Eletrorretinografia , Potenciais Evocados Visuais , Humanos , Camundongos
8.
Neurobiol Aging ; 67: 181-188, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29735432

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disease leading to neuronal dysfunctions with cognitive impairment. AD can affect visual pathways and visual cortex and result in various visual changes and problems. However, how early the visual dysfunctions occur in AD is still a matter of discussion. Here, we used electrophysiological techniques to show the presence of early anomalies in AD visual system. To this aim, we used a familial AD (FAD) model, the 5xFAD transgenic mouse, characterized by severe progressive amyloid pathology and cognitive deficits. We investigated the retina and primary visual cortex responsivity together with behavioral assessment of the visual acuity. Visual tests and recordings were conducted at different ages in 5xFAD mice, corresponding to different phases of neurodegeneration and beta amyloid accumulation. We showed that the visual system is impaired in 5xFAD mice. In particular, we found that the inner retina impairment precedes neuronal disorders in other brain areas and cognitive deficits. Thus, noninvasive retinal electrophysiology can provide a support for assessing early visual dysfunctions in AD.


Assuntos
Doença de Alzheimer/fisiopatologia , Retina/fisiopatologia , Transtornos da Visão/etiologia , Acuidade Visual , Córtex Visual/fisiopatologia , Vias Visuais/fisiopatologia , Doença de Alzheimer/complicações , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Disfunção Cognitiva/etiologia , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Transgênicos , Transtornos da Visão/diagnóstico , Transtornos da Visão/fisiopatologia
9.
Clin Cancer Res ; 24(18): 4371-4379, 2018 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-29895707

RESUMO

Purpose: The oral BCL-2 inhibitor venetoclax is an effective therapy for patients with relapsed/refractory (R/R) chronic lymphocytic leukemia (CLL), including disease with high-risk genomic features such as chromosome 17p deletion [del(17p)] or progressive disease following B-cell receptor pathway inhibitors.Patients and Methods: We conducted a comprehensive analysis of the safety of 400 mg daily venetoclax monotherapy in 350 patients with CLL using an integrated dataset from three phase I/II studies.Results: Median age was 66 years and 60% had del(17p). Patients had received a median of three prior therapies (range: 0-15); 42% previously received ibrutinib or idelalisib. Median duration of exposure to venetoclax was 16 months (0-56). In the pooled analysis, the most common adverse events (AE) of any grade were diarrhea (41%), neutropenia (40%), nausea (39%), anemia (31%), fatigue (28%), and upper respiratory tract infection (25%). The most common grade 3/4 AEs were neutropenia (37%), anemia (17%), and thrombocytopenia (14%). With the current 5-week ramp-up dosing, the incidence of laboratory TLS was 1.4% (2/166), none had clinical sequelae, and all of these patients were able to ramp-up to a daily dose of 400 mg. Grade 3/4 neutropenia was manageable with growth factor support and dose adjustments; the incidence of serious infections in these patients was 15%. Ten percent of patients discontinued venetoclax due to AEs and 8% died while on study, with the majority of deaths in the setting of disease progression.Conclusions: Venetoclax as a long-term continuous therapy is generally well tolerated in patients with R/R CLL when initiated with the current treatment algorithm. Clin Cancer Res; 24(18); 4371-9. ©2018 AACR.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/classificação , Trato Gastrointestinal/efeitos dos fármacos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Sulfonamidas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Compostos Bicíclicos Heterocíclicos com Pontes/administração & dosagem , Compostos Bicíclicos Heterocíclicos com Pontes/efeitos adversos , Deleção Cromossômica , Cromossomos Humanos Par 17/genética , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Trato Gastrointestinal/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/genética , Síndrome de Smith-Magenis/tratamento farmacológico , Síndrome de Smith-Magenis/genética , Síndrome de Smith-Magenis/patologia , Sulfonamidas/administração & dosagem , Sulfonamidas/efeitos adversos , Resultado do Tratamento , Proteína Supressora de Tumor p53/genética
10.
Front Cell Neurosci ; 11: 53, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28289378

RESUMO

Alzheimer's disease (AD) and glaucoma are two distinct multifactorial neurodegenerative diseases, primarily affecting the elderly. Common pathophysiological mechanisms have been elucidated in the past decades. First of all both diseases are progressive, with AD leading to dementia and glaucoma inducing blindness. Pathologically, they all feature synaptic dysfunction with changes of neuronal circuitry, progressive accumulation of protein aggregates such as the beta amyloid (Aß) and intracellular microtubule inclusions containing hyperphosphorylated tau, which belongs to microtubule associated protein family. During an early phase of degeneration, both diseases are characterized by synaptic dysfunction and changes of mitogen-activated protein kinases (MAPK). Common degenerative mechanisms underlying both diseases are discussed here, along with recent results on the potential use of the visual system as a biomarker for diagnosis and progression of AD. Common neuropathological changes and mechanisms in AD and glaucoma have facilitated the transfer of therapeutic strategies between diseases. In particular, we discuss past and present evidence for neuroprotective effects of brain-derived neurotrophic factor (BDNF).

11.
Sci Rep ; 7(1): 11140, 2017 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-28894266

RESUMO

We generated 6 transgenic lines with insertion of an expression plasmid for the R883/M xanthine dehydrogenase (XDH) mutant protein. Approximately 20% of the animals deriving from one of the transgenic lines show ocular abnormalities and an increase in intra-ocular pressure which are consistent with glaucoma. The observed pathologic phenotype is not due to expression of the transgene, but rather the consequence of the transgene insertion site, which has been defined by genome sequencing. The insertion site maps to chromosome 1qA3 in close proximity to the loci encoding AP-2ß and AP-2δ, two proteins expressed in the eye. The insertion leads to a reduction in AP-2ß and AP-2δ levels. Down-regulation of AP-2ß expression is likely to be responsible for the pathologic phenotype, as conditional deletion of the Tfap2b gene in the neural crest has recently been shown to cause defective development of the eye anterior segment and early-onset glaucoma. In these conditional knock-out and our transgenic mice, the morphological/histological features of the glaucomatous pathology are surprisingly similar. Our transgenic mouse represents a model of angle-closure glaucoma and a useful tool for the study of the pathogenesis and the development of innovative therapeutic strategies.


Assuntos
Suscetibilidade a Doenças , Expressão Gênica , Glaucoma/genética , Fator de Transcrição AP-2/genética , Animais , Cromossomos , Modelos Animais de Doenças , Dosagem de Genes , Ordem dos Genes , Vetores Genéticos , Glaucoma/metabolismo , Glaucoma/fisiopatologia , Imuno-Histoquímica , Camundongos , Camundongos Transgênicos , Mutagênese Insercional , Fenótipo , Fator de Transcrição AP-2/metabolismo , Xantina Desidrogenase/genética , Xantina Desidrogenase/metabolismo
12.
Cancer Chemother Pharmacol ; 58(5): 585-93, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16680463

RESUMO

PURPOSE: Recent clinical studies have demonstrated a reduction of irinotecan (CPT-11) gastrointestinal toxicities when the CPT-11 is administered in combination with thalidomide in patients with diagnosis of colorectal cancer. The main purpose of this study was to investigate possible interactions between CPT-11 pharmacokinetics and thalidomide to explain the previously described gastrointestinal toxicity reduction. METHODS: In our clinical trial, advanced cancer patients were treated with CPT-11 on a dose of 350 mg/m2 at day 1 every 3 weeks. Only at the first cycle, CPT-11 was administered in association with thalidomide on a dose of 400 mg/day given from day 1 to day 14. From the second cycle, the treatment was continued with irinotecan alone at the same dose. Pharmacokinetics analysis of irinotecan and its metabolites, SN-38 and SN-38-glucuronide, were performed at the first and second cycle. RESULTS: A total of 19 patients entered the study. The pharmacokinetic analysis were performed on 16 patients. Pharmacokinetic data suggested a decreased metabolism of irinotecan into SN-38 and SN-38-glucuronide when it was administered with thalidomide. Indeed, area under the time-concentration curve (AUC) of SN-38 was significantly lower at the first cycle than the second cycle (0.99+/-0.45 hxmicrog/ml vs 1.34+/-0.65, respectively, P=0.027) whereas AUC of irinotecan and SN-38-glucuronide were higher at first cycle than second cycle (34.53+/-11.38 hxmicrog/ml vs. 28.42+/-12.23 hxmicrog/ml, P=0.064 and 2.39+/-1.21 h(microg/ml vs. 1.86+/-1.11 hxmicrog/ml, P=0.018, respectively). CONCLUSIONS: Our study demonstrates a significant decreased metabolism of CPT-11 into the active metabolite SN-38 when CPT-11 is administered in association with thalidomide. These observations strongly suggest an interaction of thalidomide with CPT-11 metabolism and, at least in part, it might explain the previously described improvement in tolerability.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Administração Oral , Idoso , Antineoplásicos Fitogênicos/metabolismo , Antineoplásicos Fitogênicos/farmacocinética , Antineoplásicos Fitogênicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Área Sob a Curva , Neoplasias Encefálicas/patologia , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Camptotecina/sangue , Camptotecina/farmacocinética , Diarreia/induzido quimicamente , Distúrbios do Sono por Sonolência Excessiva/induzido quimicamente , Esquema de Medicação , Feminino , Meia-Vida , Humanos , Infusões Intravenosas , Irinotecano , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Talidomida/administração & dosagem , Talidomida/efeitos adversos , Resultado do Tratamento
13.
Transl Vis Sci Technol ; 4(6): 1, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27190697

RESUMO

PURPOSE: To test whether the topical eye treatment with BDNF prevents the effects of continuous light exposure (LE) in the albino rat retina. METHODS: Two groups of albino rats were used. The first group of rats received an intraocular injection of BDNF (2 µL, 1 µg/µL) before LE, while the second group was treated with one single drop of BDNF (10 µL, 12 µg/µL) dissolved in different types of solutions (physiological solution, the polysaccharide fraction of Tamarind gum, TSP, and sodium carboxy methyl cellulose), at the level of conjunctival fornix before LE. The level of BDNF in the retina and optic nerve was determined by enzyme-linked immunosorbent assay. We recorded the flash electroretinogram (fERG) in dark adapted rats 1 week after LE. At the end of the recording session, the retinas were removed and labeled so that the number of photoreceptors nuclear rows and thickness of the outer nuclear layer was analyzed. RESULTS: Intravitreal injection of BDNF before LE prevented fERG impairment. Different ophthalmic preparations were used for topical eye application; the TSP resulted the most suitable vehicle to increase BDNF level in the retina and optic nerve. Topical eye application with BDNF/TSP before LE partially preserved both fERG response and photoreceptors. CONCLUSIONS: Topical eye treatment with BDNF represents a suitable, noninvasive tool to increase the retinal content of BDNF up to a level capable of exerting neuroprotection toward photoreceptors injured by prolonged LE. TRANSLATIONAL RELEVANCE: A collyrium containing BDNF may serve as an effective, clinically translational treatment against retinal degeneration.

14.
PLoS One ; 9(12): e115579, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25536045

RESUMO

Vision loss in glaucoma is caused by progressive dysfunction of retinal ganglion cells (RGCs) and optic nerve atrophy. Here, we investigated the effectiveness of BDNF treatment to preserve vision in a glaucoma experimental model. As an established experimental model, we used the DBA/2J mouse, which develops chronic intraocular pressure (IOP) elevation that mimics primary open-angle glaucoma (POAG). IOP was measured at different ages in DBA/2J mice. Visual function was monitored using the steady-state Pattern Electroretinogram (P-ERG) and visual cortical evoked potentials (VEP). RGC alterations were assessed using Brn3 immunolabeling, and confocal microscope analysis. Human recombinant BDNF was dissolved in physiological solution (0.9% NaCl); the effects of repeated intravitreal injections and topical eye BDNF applications were independently evaluated in DBA/2J mice with ocular hypertension. BDNF level was measured in retinal homogenate by ELISA and western blot. We found a progressive decline of P-ERG and VEP responses in DBA/2J mice between 4 and 7 months of age, in relationship with the development of ocular hypertension and the reduction of Brn3 immunopositive RGCs. Conversely, repeated intravitreal injections (BDNF concentration = 2 µg/µl, volume = 1 µl, for each injection; 1 injection every four days, three injections over two weeks) and topical eye application of BDNF eye-drops (12 µg/µl, 5 µl eye-drop every 48 h for two weeks) were able to rescue visual responses in 7 month DBA/2J mice. In particular, BDNF topical eye treatment recovered P-ERG and VEP impairment increasing the number of Brn3 immunopositive RGCs. We showed that BDNF effects were independent of IOP reduction. Thus, topical eye treatment with BDNF represents a promisingly safe and feasible strategy to preserve visual function and diminish RGC vulnerability to ocular hypertension.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/uso terapêutico , Glaucoma/tratamento farmacológico , Glaucoma/fisiopatologia , Retina/fisiopatologia , Administração Oftálmica , Animais , Fator Neurotrófico Derivado do Encéfalo/administração & dosagem , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Modelos Animais de Doenças , Eletrorretinografia , Potenciais Evocados Visuais/efeitos dos fármacos , Humanos , Pressão Intraocular/efeitos dos fármacos , Injeções Intravítreas , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Ratos Wistar , Retina/efeitos dos fármacos , Retina/patologia , Células Ganglionares da Retina/efeitos dos fármacos , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/patologia , Fator de Transcrição Brn-3A/metabolismo
15.
Clin Cancer Res ; 17(16): 5257-67, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21712447

RESUMO

PURPOSE: VEGF receptor 2 (VEGFR-2) plays a crucial role in mediating angiogenic endothelial cell responses via the VEGF pathway, and angiogenesis inhibitors targeting VEGFR-2 are in clinical use. As angiogenesis is a host-driven process, functional heritable variation in KDR, the gene encoding VEGFR-2, may affect VEGFR-2 function and, ultimately, the extent of tumor angiogenesis. EXPERIMENTAL DESIGN: We resequenced KDR using 24 DNAs each from healthy Caucasian, African American, and Asian groups. Nonsynonymous genetic variants were assessed for function by phosphorylation assays. Luciferase reporter gene assays were used to examine effects of variants on gene expression. KDR mRNA and protein expression and microvessel density (MVD) were measured in non-small cell lung cancer (NSCLC) tumor samples, and matching patient DNA samples were genotyped to test for associations with variants of interest. RESULTS: KDR resequencing led to the discovery of 120 genetic variants, of which 25 had not been previously reported. Q472H had increased VEGFR-2 protein phosphorylation and associated with increased MVD in NSCLC tumor samples. -2854C and -2455A increased luciferase expression and associated with higher KDR mRNA levels in NSCLC samples. -271A reduced luciferase expression and associated with lower VEGFR-2 levels in NSCLC samples. -906C and 23408G associated with higher KDR mRNA levels in NSCLC samples. CONCLUSIONS: This study has defined KDR genetic variation in 3 populations and identified common variants that impact on tumoral KDR expression and vascularization. These findings may have important implications for understanding the molecular basis of genetic associations between KDR variation and clinical phenotypes related to VEGFR-2 function.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Mutação em Linhagem Germinativa , Neoplasias Pulmonares/genética , Microvasos/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Análise de Variância , Sequência de Bases , Carcinoma Pulmonar de Células não Pequenas/irrigação sanguínea , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular , Feminino , Regulação Neoplásica da Expressão Gênica , Frequência do Gene , Genótipo , Células HEK293 , Humanos , Imuno-Histoquímica , Modelos Lineares , Pulmão/irrigação sanguínea , Pulmão/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/metabolismo , Masculino , Microvasos/patologia , Pessoa de Meia-Idade , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Fosforilação , Polimorfismo de Nucleotídeo Único , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
16.
J Craniofac Surg ; 17(5): 876-9, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17003614

RESUMO

Bisphosphonates (BPs) are used to inhibit bone resorption. Recently, they have been used in cancer patients to prevent bone loss due to bone metastasis. Fourteen consecutive patients, undergoing BPs monthly IV infusion due to neoplastic bone diseases, were diagnosed with osteonecrosis of the jaws. None of the patients had been previously undergoing radiotherapy of the head and neck region. Eight patients showed maxillary involvement, and nine patients had had a recent tooth extraction in the osteonecrosis areas. Biopsies and surgical debridment were performed. Histologically, none of the patients showed signs of bone metastasis. As high-dosage long-term BP therapy appears to be associated with osteonecrosis of the jaws, dental practitioners should exercise caution in the treatment of such patients.


Assuntos
Conservadores da Densidade Óssea/efeitos adversos , Difosfonatos/efeitos adversos , Doenças Maxilomandibulares/induzido quimicamente , Osteonecrose/induzido quimicamente , Idoso , Idoso de 80 Anos ou mais , Conservadores da Densidade Óssea/uso terapêutico , Difosfonatos/uso terapêutico , Feminino , Humanos , Doenças Maxilomandibulares/terapia , Masculino , Pessoa de Meia-Idade , Osteonecrose/terapia
17.
Ann Surg Oncol ; 13(1): 58-65, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16372158

RESUMO

BACKGROUND: The prognosis of unresectable metastatic colorectal cancer might be improved if a radical surgical resection of metastases could be performed after a response to chemotherapy. METHODS: We treated 74 patients with unresectable metastatic colorectal cancer (not selected for a neoadjuvant approach) with irinotecan, oxaliplatin, and 5-fluorouracil/leucovorin (FOLFOXIRI and simplified FOLFOXIRI). Because of the high activity of these regimens (response rate, 72%), a secondary curative operation could be performed in 19 patients (26%). RESULTS: Four patients underwent an extended hepatectomy, nine patients underwent a right hepatectomy, three patients underwent a left hepatectomy, and three patients had a segmental resection. In five patients, surgical removal of extrahepatic disease was also performed. In seven patients, surgical resection was combined with intraoperative radiofrequency ablation. The median overall survival of the 19 patients who underwent operation is 36.8 months, and the 4-year survival rate is 37%. The median overall survival of the 34 patients who were responsive to chemotherapy, but who did not undergo operation, is 22.2 months (P = .0114). CONCLUSIONS: The FOLFOXIRI regimens we studied have significant antitumor activity and allow a radical surgical resection of metastases in patients with initially unresectable metastatic colorectal cancer not selected for a neoadjuvant approach and also those with extrahepatic disease. The median survival of patients with resected disease is promising.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/patologia , Hepatectomia/métodos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Idoso , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Terapia Combinada , Progressão da Doença , Feminino , Fluoruracila/administração & dosagem , Humanos , Irinotecano , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Prognóstico , Análise de Sobrevida , Resultado do Tratamento
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