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1.
Cell Rep ; 38(3): 110262, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35045281

RESUMO

Disruption of retromer-dependent endosomal trafficking is considered pathogenic in late-onset Alzheimer's disease (AD). Here, to investigate this disruption in the intact brain, we turn to a genetic mouse model where the retromer core protein VPS35 is depleted in hippocampal neurons, and then we replete VPS35 using an optimized viral vector protocol. The VPS35 depletion-repletion studies strengthen the causal link between the neuronal retromer and AD-associated neuronal phenotypes, including the acceleration of amyloid precursor protein cleavage and the loss of synaptic glutamate receptors. Moreover, the studies show that the neuronal retromer can regulate a distinct, dystrophic, microglia morphology, phenotypic of hippocampal microglia in AD. Finally, the neuronal and, in part, the microglia responses to VPS35 depletion were found to occur independent of tau. Showing that the neuronal retromer can regulate AD-associated pathologies in two of AD's principal cell types strengthens the link, and clarifies the mechanism, between endosomal trafficking and late-onset sporadic AD.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Microglia/patologia , Neurônios/patologia , Proteínas de Transporte Vesicular/metabolismo , Animais , Endossomos/metabolismo , Camundongos , Microglia/metabolismo , Neurônios/metabolismo , Fenótipo , Transporte Proteico/fisiologia
2.
Cell Rep ; 37(13): 110182, 2021 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-34965419

RESUMO

Whether and how the pathogenic disruptions in endosomal trafficking observed in Alzheimer's disease (AD) are linked to its anatomical vulnerability remain unknown. Here, we began addressing these questions by showing that neurons are enriched with a second retromer core, organized around VPS26b, differentially dedicated to endosomal recycling. Next, by imaging mouse models, we show that the trans-entorhinal cortex, a region most vulnerable to AD, is most susceptible to VPS26b depletion-a finding validated by electrophysiology, immunocytochemistry, and behavior. VPS26b was then found enriched in the trans-entorhinal cortex of human brains, where both VPS26b and the retromer-related receptor SORL1 were found deficient in AD. Finally, by regulating glutamate receptor and SORL1 recycling, we show that VPS26b can mediate regionally selective synaptic dysfunction and SORL1 deficiency. Together with the trans-entorhinal's unique network properties, hypothesized to impose a heavy demand on endosomal recycling, these results suggest a general mechanism that can explain AD's regional vulnerability.


Assuntos
Doença de Alzheimer/patologia , Encéfalo/patologia , Endossomos/patologia , Proteínas Relacionadas a Receptor de LDL/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Proteínas de Transporte Vesicular/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Animais , Encéfalo/metabolismo , Estudos de Casos e Controles , Endossomos/metabolismo , Feminino , Humanos , Proteínas Relacionadas a Receptor de LDL/genética , Masculino , Proteínas de Membrana Transportadoras/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Neuroimagem , Transporte Proteico , Proteínas de Transporte Vesicular/química , Proteínas de Transporte Vesicular/genética
3.
Sci Transl Med ; 12(571)2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33239387

RESUMO

Endosomal trafficking has emerged as a defective biological pathway in Alzheimer's disease (AD), and the pathway is a source of cerebrospinal fluid (CSF) protein accumulation. Nevertheless, the identity of the CSF proteins that accumulate in the setting of defects in AD's endosomal trafficking pathway remains unknown. Here, we performed a CSF proteomic screen in mice with a neuronal-selective knockout of the core of the retromer complex VPS35, a master conductor of endosomal traffic that has been implicated in AD. We then validated three of the most relevant proteomic findings: the amino terminus of the transmembrane proteins APLP1 and CHL1, and the mid-domain of tau, which is known to be unconventionally secreted and elevated in AD. In patients with AD dementia, the concentration of amino-terminal APLP1 and CHL1 in the CSF correlated with tau and phosphorylated tau. Similar results were observed in healthy controls, where both proteins correlated with tau and phosphorylated tau and were elevated in about 70% of patients in the prodromal stages of AD. Collectively, the mouse-to-human studies suggest that retromer-dependent endosomal trafficking can regulate tau, APLP1, and CHL1 CSF concentration, informing on how AD's trafficking pathway might contribute to disease spread and how to identify its trafficking impairments in vivo.


Assuntos
Doença de Alzheimer , Precursor de Proteína beta-Amiloide/líquido cefalorraquidiano , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Biomarcadores , Moléculas de Adesão Celular , Humanos , Camundongos , Sintomas Prodrômicos , Proteômica , Proteínas de Transporte Vesicular , Proteínas tau
4.
Mol Cell Biol ; 40(19)2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32690545

RESUMO

Neuronal ceroid lipofuscinosis (NCL) is one of the most prevalent neurodegenerative disorders of early life, Parkinson's disease (PD) is the most common neurodegenerative disorder of midlife, while Alzheimer's disease (AD) is the most common neurodegenerative disorder of late life. While they are phenotypically distinct, recent studies suggest that they share a biological pathway, retromer-dependent endosomal trafficking. A retromer is a multimodular protein assembly critical for sorting and trafficking cargo out of the endosome. As a lysosomal storage disease, all 13 of NCL's causative genes affect endolysosomal function, and at least four have been directly linked to retromer. PD has several known causative genes, with one directly linked to retromer and others causing endolysosomal dysfunction. AD has over 25 causative genes/risk factors, with several of them linked to retromer or endosomal trafficking dysfunction. In this article, we summarize the emerging evidence on the association of genes causing NCL with retromer function and endosomal trafficking, review the recent evidence linking NCL genes to AD, and discuss how NCL, AD, and PD converge on a shared molecular pathway. We also discuss this pathway's role in microglia and neurons, cell populations which are critical to proper brain homeostasis and whose dysfunction plays a key role in neurodegeneration.


Assuntos
Doença de Alzheimer/metabolismo , Endossomos/metabolismo , Lipofuscinoses Ceroides Neuronais/genética , Lipofuscinoses Ceroides Neuronais/metabolismo , Doença de Parkinson/metabolismo , Doença de Alzheimer/genética , Animais , Transporte Biológico , Humanos , Doença de Parkinson/genética , Presenilina-1/genética , Presenilina-1/metabolismo
5.
Mol Cell Biol ; 38(20)2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30037983

RESUMO

In a whole-exome sequencing study of multiplex Alzheimer's disease (AD) families, we investigated three neuronal ceroid lipofuscinosis genes that have been linked to retromer, an intracellular trafficking pathway associated with AD: ceroid lipofuscinosis 3 (CLN3), ceroid lipofuscinosis 5 (CLN5), and cathepsin D (CTSD). We identified a missense variant in CLN5 c.A959G (p.Asn320Ser) that segregated with AD. We find that this variant causes glycosylation defects in the expressed protein, which causes it to be retained in the endoplasmic reticulum with reduced delivery to the endolysosomal compartment, CLN5's normal cellular location. The AD-associated CLN5 variant is shown here to reduce the normal processing of cathepsin D and to decrease levels of full-length amyloid precursor protein (APP), suggestive of a defect in retromer-dependent trafficking.


Assuntos
Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Catepsina D/metabolismo , Mutação com Perda de Função , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Lipofuscinoses Ceroides Neuronais/genética , Lipofuscinoses Ceroides Neuronais/metabolismo , Sequência de Aminoácidos , Precursor de Proteína beta-Amiloide/metabolismo , Retículo Endoplasmático/metabolismo , Endossomos/metabolismo , Glicosilação , Células HeLa , Humanos , Proteínas de Membrana Lisossomal , Lisossomos/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Mutação de Sentido Incorreto , Processamento de Proteína Pós-Traducional , Transporte Proteico , Homologia de Sequência de Aminoácidos , Sequenciamento do Exoma
6.
J Neurooncol ; 136(2): 281-287, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29170908

RESUMO

Prior studies of post-operative stereotactic radiosurgery (SRS) have not distinguished between Adjuvant SRS (ARS) versus Adjuvant SRS to residual/recurrent disease (ARD). In this study, we defined ARS and ARD and investigated local control (LC), overall survival (OS), distant development of brain metastases (DBF), and leptomeningeal disease (LMD). We retrospectively identified BM patients who received surgical resection and SRS for BM from an IRB approved database between Jan 2009-Aug 2015. Patients were stratified into two groups: ARS and ARD. LC was determined by follow-up MRI studies and OS was measured from the date of surgery. LC and OS were assessed using the Kaplan-Meier method. 70 cavities underwent surgical resection of BM and received SRS to the post-operative bed. 41 cavities were classified as ARS and 29 as ARD. There was no significant difference in 12-month LC between the ARS and ARD group (71.4 vs. 80.8%, respectively; p = 0.135) from the time point of SRS. The overall 1-year survival for ARS and ARD was 79.9 and 86.1%, respectively (p = 0.339). Mean time to progression was 6.45 and 8.0 months and median follow-up was 10 and 15 months for ARS and ARD, respectively. 11.8% of ARS patients and 15.4% of ARD patients developed LMD, p = 0.72. 29.4% of ARS and 48.0% of ARD patients developed DBF, p = 0.145. Our findings suggest that observation after surgical resection, with subsequent treatment with SRS after the development of local failure, may not compromise treatment efficacy. If validated, this would spare patients who do not recur post-surgically from additional treatment.


Assuntos
Neoplasias Encefálicas/radioterapia , Recidiva Local de Neoplasia/radioterapia , Radiocirurgia , Neoplasias Encefálicas/secundário , Progressão da Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Radioterapia Adjuvante , Estudos Retrospectivos , Resultado do Tratamento
7.
EuroIntervention ; 11(14): e1627-38, 2016 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-27056123

RESUMO

AIMS: Bivalirudin use as a procedural anticoagulant in patients undergoing percutaneous coronary intervention (PCI) is associated with a lower incidence of thrombocytopaenia compared to other antithrombotic agents. We aimed to evaluate the prognostic impact of baseline thrombocytopaenia and early changes in platelet counts among patients undergoing PCI with exclusive use of bivalirudin. METHODS AND RESULTS: We evaluated 7,505 patients who underwent PCI over a period of eight years. Patients who received unfractionated heparin and glycoprotein IIb/IIIa receptor inhibitors were specifically excluded. Eight hundred and fifty-eight (11.4%) patients had baseline thrombocytopaenia and 451 (6.0%) developed acquired thrombocytopaenia. After adjustment for potential covariates, moderate to severe acquired thrombocytopaenia was the strongest independent predictor (HR 4.34, 95% CI: 2.13-8.84; p<0.001) of in-hospital net adverse clinical events, which included major adverse cardiac events and major bleeding complications. Age, male gender, baseline platelet count and intra-aortic balloon pump (IABP) insertion were independent predictors of in-hospital acquired thrombocytopaenia. After a mean follow-up of 2.6±1.7 years, moderate to severe baseline thrombocytopaenia (HR 2.42, 95% CI: 1.79-3.29; p<0.001), moderate to severe acquired thrombocytopaenia (HR 2.37, 95% CI: 1.13-4.97; p=0.02) and severe changes in platelet count (>67 k) were significant predictors of mortality. CONCLUSIONS: In patients undergoing PCI with bivalirudin, moderate to severe baseline and acquired thrombocytopaenia along with severe changes in platelet count are associated with higher long-term mortality.


Assuntos
Antitrombinas/uso terapêutico , Fragmentos de Peptídeos/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Trombocitopenia/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Angioplastia Coronária com Balão/métodos , Anticoagulantes/uso terapêutico , Feminino , Heparina/uso terapêutico , Hirudinas , Humanos , Masculino , Pessoa de Meia-Idade , Intervenção Coronária Percutânea/métodos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Proteínas Recombinantes/uso terapêutico , Trombocitopenia/mortalidade , Resultado do Tratamento
8.
Pract Radiat Oncol ; 6(5): 306-314, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26952813

RESUMO

PURPOSE: Adjuvant hypofractionated radiation therapy (HRT) for elderly patients with newly diagnosed glioblastoma (GBM) is a reasonable option compared with standard fractionation radiation therapy (SFRT). Outcomes in patients receiving HRT in the presence of temozolomide (TMZ) compared with SFRT with TMZ are unclear. We examined HRT for GBM with TMZ in comparison to SFRT with TMZ. METHODS AND MATERIALS: We conducted a retrospective analysis of patients ≥60 years of age with newly diagnosed GBM who received SFRT or HRT from 1994 to 2014 in the postoperative setting. Inclusion criteria included SFRT (60 Gy/30 fractions or 59.4 Gy/33 fractions) versus HRT (40 Gy/15 fractions). RESULTS: In this cohort, 158 patients were treated with SFRT versus 26 with HRT. Median survival in patients receiving SFRT compared with HRT was 430 and 475 days (P = .550), respectively. Ninety-five percent of the SFRT patients received TMZ versus 100% of those treated with HRT. Patients receiving HRT were older (median, 72 vs 66 years). All HRT patients were treated with the intensity modulated radiation therapy (IMRT) technique versus SFRT, in which 57% had IMRT. Multivariate Cox regression showed decreased overall survival (OS) associated with patient age >70 (hazard ratio [HR], 1.84), lower Karnofsky performance status (HR, 5.25), biopsy versus surgical resection (HR, 4.18), radiation therapy planning technique 3- or 2-dimensional planning versus IMRT (HR, 1.91; HR, 3.40, respectively). Analysis restricted to patients receiving IMRT-based planning showed no difference in OS between HRT and SFRT. For patients receiving TMZ, there was no survival difference between those treated with HRT and those treated with SFRT. CONCLUSIONS: Elderly GBM patients receiving HRT and those receiving SFRT had similar OS. Subset analysis patients receiving concurrent TMZ showed no difference in OS between the HRT and SFRT groups.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Dacarbazina/análogos & derivados , Idoso , Antineoplásicos Alquilantes/administração & dosagem , Quimiorradioterapia , Dacarbazina/administração & dosagem , Dacarbazina/uso terapêutico , Fracionamento da Dose de Radiação , Feminino , Glioblastoma , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Temozolomida
9.
World Neurosurg ; 88: 260-269, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26746331

RESUMO

BACKGROUND: Studies have shown racial differences in cancer outcomes. We investigate whether survival differences existed in Hispanic patients with glioblastoma (GBM) compared with other ethnicities from our modern radiotherapy series, because no study to date has focused on outcomes in this group after radiation therapy. METHODS: We retrospectively evaluated 428 patients diagnosed with GBM from 1996 to 2014 at our institution, divided into 4 groups based on self-report: white, black, Hispanic, and Asian/Indian. The primary outcome was overall survival. We analyzed differences in prognostic factors among the whole cohort compared with the Hispanic cohort alone. RESULTS: Baseline characteristics of the 4 racial groups were comparable. With a median follow-up of 387 days, no survival differences were seen by Kaplan-Meier analysis. Median overall survival for Hispanic patients was 355 days versus 450 days for the entire cohort. Factors significant for patient outcomes in the entire cohort differed slightly from those specific to Hispanic patients. Low Karnofsky Performance Status was significant on multivariate analysis in the whole population, but not in Hispanic patients. Extent of resection, recursive partitioning analysis class, and radiation therapy total dose were significant on multivariate analysis in both the whole population and Hispanic patients. CONCLUSIONS: We found that Hispanic patients with GBM had no difference in survival compared with other ethnicities in our cohort. Differences exist in factors associated with outcomes on single and multivariate analysis for Hispanic patients with GBM compared with the entire cohort. Additional studies focusing on Hispanic patients will aid in more personalized treatment approaches in this group.


Assuntos
Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/radioterapia , Irradiação Craniana/mortalidade , Glioblastoma/mortalidade , Glioblastoma/radioterapia , Hispânico ou Latino/estatística & dados numéricos , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , New York/etnologia , Prevalência , Dosagem Radioterapêutica , Fatores de Risco , Distribuição por Sexo , Taxa de Sobrevida
10.
J Neurooncol ; 127(1): 103-10, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26615564

RESUMO

We investigated effects of breast cancer subtype on overall survival (OS), local and distant control, and time from initial diagnosis to brain metastases (BM). We also investigated advances in graded prognostic assessment (GPA) scores. A cohort of 72 patients treated for BM from breast cancer with Gamma Knife stereotactic radiosurgery at our institution from 2000 to 2014 had subtyping available and were used for this study. Median follow up for OS was 12 months and for control was 6 months. OS for luminal, HER2, and triple negative subtypes were 26, 20, and 22 months. OS when stratified by Sperduto et al. (J Clin Oncol 30(4):419-425, 2012) and Subbiah et al. (J Clin Oncol 33(20):2239-2245, 2015) GPAs were similar (p = 0.087 and p = 0.063). KPS and treatment modality were significant for OS (p = 0.002; p = 0.034). On univariate analysis, triple negative subtype and >3 BM were trending and significant for decreased OS (p = 0.084; p = 0.047). On multivariable analysis HER2, triple negative, and >3 BM were significant for OS (p = 0.022; p = 0.040; p = 0.009). Subtype was significant for response on a per lesion basis (p = 0.007). Subtype was trending towards significance when analyzing time from initial diagnosis to BM treatment (p = 0.064). Breast cancer subtype is an important prognostic factor when stratifying breast cancer patients with BM. The addition of number of BM to the GPA is a useful addition and should be further investigated. Subtype has an effect on lesion response, and also on rate of development BM after initial diagnosis.


Assuntos
Neoplasias Encefálicas/secundário , Neoplasias da Mama/patologia , Radiocirurgia , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/cirurgia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/cirurgia , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/cirurgia
11.
Neurosurgery ; 78(5): 676-82, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26440447

RESUMO

BACKGROUND: The standard of care for patients with newly diagnosed glioblastoma (GBM) is maximal safe resection followed by adjuvant radiation therapy (RT) and temozolomide (TMZ). OBJECTIVE: To investigate whether the timing of adjuvant RT after surgery affected outcome in patients with GBM. METHODS: We retrospectively reviewed all patients with a diagnosis of GBM at our institution. A total of 447 patients were included in our analysis. Patients were divided into 3 equal groups based on the interval between surgery and RT. The primary outcome was overall survival (OS). RESULTS: Patients who began RT less than 21 days after surgery tended to be older, have a lower a Karnofsky Performance Status score, and higher recursive partitioning analysis class. These patients were more likely to have undergone biopsy only and received 3-dimensional conformal RT or 2-dimensional RT. The median OS for patients who started RT less than 21 days after surgery, between 21 and 32 days after surgery, and more than 32 days after surgery was 374, 465, and 478 days, respectively (P = .004). On multivariate Cox regression analysis, Karnofsky Performance Status score lower than 70, undergoing biopsy only, recursive partitioning analysis classes IV and V/VI, use of less than 36 Gy RT, and lack of TMZ chemotherapy were predictors of worse OS. The interval between surgery and RT was not significantly associated with OS on multivariate analysis. CONCLUSION: Patients who begin RT less than 21 days after surgery tend to have worse prognostic factors than those who begin RT later. When accounting for significant covariates, the effect of timing between surgery and RT is not significant.


Assuntos
Neoplasias Encefálicas/terapia , Glioblastoma/terapia , Radioterapia Adjuvante/métodos , Adulto , Idoso , Antineoplásicos Alquilantes/uso terapêutico , Biomarcadores , Biópsia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Terapia Combinada , Dacarbazina/análogos & derivados , Dacarbazina/uso terapêutico , Feminino , Glioblastoma/tratamento farmacológico , Glioblastoma/radioterapia , Humanos , Avaliação de Estado de Karnofsky , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Estudos Retrospectivos , Análise de Sobrevida , Temozolomida , Resultado do Tratamento
12.
Neurosurgery ; 77(1): 119-25; discussion 125, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25830600

RESUMO

BACKGROUND: The energy index (EI) is a measure of dose homogeneity within a target volume calculated by the integral dose divided by the product of prescription dose and tumor volume. OBJECTIVE: To assess whether a higher EI is associated with greater local control for brain metastases (BMs) treated by Gamma Knife radiosurgery (GKRS). METHODS: We reviewed all patients treated with GKRS for BM at our institution between January 2009 and February 2014. Data on the prescription dose, prescription isodose line, minimum dose, mean dose, integral dose, tumor volume, and EI were collected. Tumor response was assessed by reviewing follow-up brain imaging studies and classified according to the Response Evaluation Criteria in Solid Tumors. Local control per lesion and dosimetric prognostic factors for local control were assessed by univariate and multivariate Cox proportional hazards regression analyses. RESULTS: Of 213 patients treated, 126 had follow-up imaging available with a median follow-up of 6 months. Three hundred seventy-three individual tumors were analyzed. Of these, 133 showed a complete response, 157 showed a partial response, 46 remained stable, and 37 developed local failure. Tumors with EI ≥1.6 mJ·mL(-1)·Gy(-1) showed a higher rate of complete response. Local control rates at 6, 11, and 17 months were 95.4%, 86.5%, and 81.5%, respectively. On univariate analysis, the following factors were associated with higher rates of local failure: prescription doses of 16 and 18 Gy compared with a prescription dose of 20 Gy. The following factors were associated with a greater rate of local control: maximum dose and mean dose. On multivariate analysis, the only statistically significant factor associated with a greater rate of local failure was prescription dose of 16 Gy compared with 20 Gy. CONCLUSION: GKRS for BM results in a high rate of local control with an 11-month rate of 86.5%. A higher EI was not significantly associated with a higher rate of local control on multivariate analysis. Prescription dose was found to be the only significant predictor of local control on multivariate analysis.


Assuntos
Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Radiocirurgia/métodos , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Dosagem Radioterapêutica
13.
Neuro Oncol ; 17(7): 1022-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25910841

RESUMO

BACKGROUND: We investigated effects of genetic alterations in epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), and Kirsten rat sarcoma viral oncogene homolog (KRAS) on overall survival (OS) and local control after stereotactic radiosurgery for brain metastases in non-small cell lung cancer (NSCLC). METHODS: A cohort of 89 out of 262 NSCLC patients (2003-2013) treated with gamma knife radiosurgery for brain metastases had genotyping available and were selected as our study population. RESULTS: Median follow-up was 12 months. Median OS rates for the EGFR, KRAS, echinoderm microtubule-associated protein-like 4 (EML4)-ALK mutated, and wild-type cohorts were 17, 7, 27, and 12 months, respectively (P = .019), and for targeted versus nontargeted therapy 21 and 11 months, respectively (P = .071). Targeted therapy was a strong predictor of increased OS on univariate (P = .037) and multivariate (P = .022) analysis. Gender, primary tumor controlled status, recursive partitioning analysis class, and graded prognostic assessment score were associated with OS (P < .05). On multivariate analysis, positive EGFR mutational status was a highly significant predictor for decreased survival (hazard ratio: 8.2; 95% CI: 2.0-33.7; P = .003). However, when we recategorized EGFR-mutant cases based on whether they received tyrosine kinase inhibitor, OS was no longer significantly shorter (hazard ratio: 1.5; P = .471). Median OS for patients with and without local failure was 17 and 12 months, respectively (P = .577). Local failure rates for EGFR, KRAS, EML4-ALK mutated, and wild-type cohorts by lesion were 8.7%, 5.4%, 4.3%, and 5.1%, respectively. CONCLUSIONS: This study suggests that EGFR tyrosine kinase mutation and ALK translocation results in improved survival to targeted therapies and that mutation status itself does not predict survival and local control in patients with brain metastases from NSCLC.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Quinase do Linfoma Anaplásico , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/secundário , Carcinoma Pulmonar de Células não Pequenas/patologia , Proteínas de Ciclo Celular/genética , Fator de Crescimento Epidérmico/genética , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Proteínas Associadas aos Microtúbulos/genética , Pessoa de Meia-Idade , Mutação , Modelos de Riscos Proporcionais , Proteínas Proto-Oncogênicas p21(ras)/genética , Radiocirurgia , Receptores Proteína Tirosina Quinases/genética , Serina Endopeptidases/genética
14.
PLoS One ; 10(3): e0120352, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25781952

RESUMO

Alzheimer's disease (AD) is a complex multifactorial disorder with poorly characterized pathogenesis. Our understanding of this disease would thus benefit from an approach that addresses this complexity by elucidating the regulatory networks that are dysregulated in the neural compartment of AD patients, across distinct brain regions. Here, we use a Systems Biology (SB) approach, which has been highly successful in the dissection of cancer related phenotypes, to reverse engineer the transcriptional regulation layer of human neuronal cells and interrogate it to infer candidate Master Regulators (MRs) responsible for disease progression. Analysis of gene expression profiles from laser-captured neurons from AD and controls subjects, using the Algorithm for the Reconstruction of Accurate Cellular Networks (ARACNe), yielded an interactome consisting of 488,353 transcription-factor/target interactions. Interrogation of this interactome, using the Master Regulator INference algorithm (MARINa), identified an unbiased set of candidate MRs causally responsible for regulating the transcriptional signature of AD progression. Experimental assays in autopsy-derived human brain tissue showed that three of the top candidate MRs (YY1, p300 and ZMYM3) are indeed biochemically and histopathologically dysregulated in AD brains compared to controls. Our results additionally implicate p53 and loss of acetylation homeostasis in the neurodegenerative process. This study suggests that an integrative, SB approach can be applied to AD and other neurodegenerative diseases, and provide significant novel insight on the disease progression.


Assuntos
Doença de Alzheimer/metabolismo , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Proteínas do Tecido Nervoso/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Animais , Humanos , Proteínas do Tecido Nervoso/genética , Ratos
15.
J Neurooncol ; 122(2): 399-408, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25687652

RESUMO

Optimal treatment of brain metastases (BMs) is debatable. However, surgery or gamma knife radiosurgery (GKRS) improves survival when combined with whole brain radiotherapy (WBRT) versus WBRT alone. We retrospectively reviewed an institutional database of patients treated with GKRS for BMs from 1998 to 2013 to explore effects of single or multi-modality therapies on survival. There were 528 patients with median age 62 years. Histologies included 257 lung, 102 breast, 62 melanoma, 40 renal cell, 29 gastrointestinal, and 38 other primary cancers. Treatments included: 206 GKRS alone, 111 GKRS plus WBRT, 109 GKRS plus neurosurgical resection (NSG), and 102 all three modalities. Median overall survival (mOS) was 16.6 months. mOS among patients with one versus multiple metastasis was 17.2 versus 16.0 months respectively (p = 0.825). For patients with one BM, mOS following GKRS alone, GKRS plus WBRT, GKRS plus NSG, and all three modalities was 9.0, 19.1, 25.5, and 25.0 months, respectively, and for patients with multiple BMs, mOS was 8.6, 20.4, 20.7, 24.5 months for the respective groups. Among all patients, multivariate analysis confirmed that tri-modality group had the longest survival (HR 0.467; 95 % CI 0.350-0.623; p < 0.001) compared to GKRS alone; however, this was not significantly different than bi-modality approaches. Uncontrolled primary extra-CNS disease, age and KPS were also independent predictors of survival. Patients treated with GKRS plus NSG, GKRS plus WBRT, or all three modalities had improved OS versus GKRS alone. In our analysis, resection and GKRS allowed avoidance of WBRT without shortening survival.


Assuntos
Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/secundário , Neoplasias da Mama/patologia , Carcinoma de Células Renais/patologia , Terapia Combinada , Irradiação Craniana , Feminino , Neoplasias Gastrointestinais/patologia , Humanos , Estimativa de Kaplan-Meier , Avaliação de Estado de Karnofsky , Neoplasias Pulmonares/patologia , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Análise Multivariada , Radiocirurgia , Estudos Retrospectivos , Adulto Jovem
16.
Neurotherapeutics ; 12(1): 94-108, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25421002

RESUMO

Many neurodegenerative disorders are characterized by the aberrant accumulation of aggregate-prone proteins. Alzheimer's disease (AD) is associated with the buildup of ß-amyloid peptides and tau, which aggregate into extracellular plaques and neurofibrillary tangles, respectively. Multiple studies have linked dysfunctional intracellular degradation mechanisms with AD pathogenesis. One such pathway is the autophagy-lysosomal system, which involves the delivery of large protein aggregates/inclusions and organelles to lysosomes through the formation, trafficking, and degradation of double-membrane structures known as autophagosomes. Converging data suggest that promoting autophagic degradation, either by inducing autophagosome formation or enhancing lysosomal digestion, provides viable therapeutic strategies. In this review, we discuss compounds that can augment autophagic clearance and may ameliorate disease-related pathology in cell and mouse models of AD. Canonical autophagy induction is associated with multiple signaling cascades; on the one hand, the best characterized is mammalian target of rapamycin (mTOR). Accordingly, multiple mTOR-dependent and mTOR-independent drugs that stimulate autophagy have been tested in preclinical models. On the other hand, there is a growing list of drugs that can enhance the later stages of autophagic flux by stabilizing microtubule-mediated trafficking, promoting lysosomal fusion, or bolstering lysosomal enzyme function. Although altering the different stages of autophagy provides many potential targets for AD therapeutic interventions, it is important to consider how autophagy drugs might also disturb the delicate balance between autophagosome formation and lysosomal degradation.


Assuntos
Doença de Alzheimer/patologia , Autofagia/fisiologia , Animais , Humanos , Lisossomos/patologia , Lisossomos/fisiologia
18.
Am J Cardiol ; 113(9): 1481-6, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24630790

RESUMO

Bleeding complications after percutaneous coronary intervention (PCI) have been associated with higher short and long-term mortality. Bivalirudin has been shown to reduce bleeding complications in patients who underwent PCI; however, the impact of anemia on bleeding complications and long-term mortality has not been studied. A total of 11,991 patients who underwent PCI over a period of 8 years with bivalirudin as the primary antithrombotic agent were included. Anemia was defined according to the World Health Organization definition. Bleeding complications were prospectively collected. Survival analysis was performed using multivariable Cox proportional hazards models. Of the 11,991 patients, 4,815 patients (40%) had baseline anemia. Major bleeding occurred in 3.3% of patients with anemia compared with 0.7% of patients without anemia (p <0.001) driven largely by transfusion events. In the overall study population, major bleeding was a significant predictor of mortality (hazard ratio [HR] 1.4, 95% confidence interval [CI] 1.04 to 1.8, p = 0.027) at a mean follow-up of 2.6 years (interquartile range 1.4 to 3.5). In patients with anemia, major bleeding remained an independent predictor of mortality (HR 1.5, 95% CI 1.1 to 2.0, p = 0.008); however, in patients without anemia, it did not (HR 1.25, 95% CI 0.52 to 3.03, p = 0.62). In patients who underwent PCI with bivalirudin therapy, major bleeding is associated with early and long-term mortality, which is more pronounced in patients with baseline anemia.


Assuntos
Anemia Hipocrômica/complicações , Antitrombinas/uso terapêutico , Hemorragia/complicações , Fragmentos de Peptídeos/uso terapêutico , Intervenção Coronária Percutânea/mortalidade , Idoso , Feminino , Hirudinas , Humanos , Masculino , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/prevenção & controle , Proteínas Recombinantes/uso terapêutico
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