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1.
Cancer ; 123(23): 4653-4662, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28786105

RESUMO

BACKGROUND: 13-Cis retinoic acid (13-CRA) is a synthetic vitamin A derivative. High-dose 13-CRA in patients with squamous cell cancers of the head and neck (SCCHNs) reduces the incidence of second primary tumors (SPTs). The authors report long-term results from a phase 3 randomized trial that compared treatment with low-dose 13-CRA versus placebo for patients who had early stage SCCHN, with a focus on the development of SPTs and overall survival (OS). METHODS: In total, 176 patients who received treatment for stage I/II SCCHN were randomized to receive either low-dose 13-CRA (weight-based dose of 7.5 mg or 10 mg) or placebo for 2 years. A competing-risk approach and the log-rank test were used to compare the time to SPT and OS, respectively, between groups. RESULTS: 13-CRA neither significantly reduced the cumulative incidence of SPT (P = .61) nor improved the time to SPT (hazard ratio [HR] for 13-CRA/placebo; 0.86; P = .61). Despite limited power, there was a trend toward improved OS for the 13-CRA arm (HR, 0.75; P = .14), particularly among patients whose index tumor was surgically excised (N = 26; HR, 0.50; P = .057) and among women (N = 39; HR, 0.44; P = .065) and never/former smokers (N = 129; HR, 0.61; P = .055), with a median follow-up of 16 years. The main 13-CRA related toxicities were dry skin and cheilitis. CONCLUSIONS: Treatment with low-dose 13-CRA for 2 years did not decrease the incidence of SPT; subset analysis indicates a potential survival advantage among patients who are women and never/former smokers. More targeted interventions based on clinical risk factors and molecular characterization of tumors may yield greater success in future prevention trials. Cancer 2017;123:4653-4662. © 2017 American Cancer Society.


Assuntos
Carcinoma de Células Escamosas/prevenção & controle , Fármacos Dermatológicos/uso terapêutico , Neoplasias de Cabeça e Pescoço/patologia , Isotretinoína/uso terapêutico , Segunda Neoplasia Primária/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/secundário , Método Duplo-Cego , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Segunda Neoplasia Primária/epidemiologia , Prognóstico , Estados Unidos/epidemiologia
3.
J Biol Chem ; 289(52): 36140-9, 2014 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-25326379

RESUMO

Ubiquitin C-terminal hydrolase L1 (UCH-L1) is a deubiquitinating enzyme that is highly expressed in neurons. A possible role for UCH-L1 in neurodegeneration has been highlighted because of its presence in Lewy bodies associated with Parkinson disease and neurofibrillary tangles observed in Alzheimer disease. UCH-L1 exists in two forms in neurons, a soluble cytoplasmic form (UCH-L1(C)) and a membrane-associated form (UCH-L1(M)). Alzheimer brains show reduced levels of soluble UCH-L1(C) correlating with the formation of UCH-L1-immunoreactive tau tangles, whereas UCH-L1(M) has been implicated in α-synuclein dysfunction. Given these reports of divergent roles, we investigated the properties of UCH-L1 membrane association. Surprisingly, our results indicate that UCH-L1 does not partition to the membrane in the cultured cell lines we tested. Furthermore, in primary cultured neurons, a proportion of UCH-L1(M) does partition to the membrane, but, contrary to a previous report, this does not require farnesylation. Deletion of the four C-terminal residues caused the loss of protein solubility, abrogation of substrate binding, increased cell death, and an abnormal intracellular distribution, consistent with protein dysfunction and aggregation. These data indicate that UCH-L1 is differently processed in neurons compared with clonal cell lines and that farnesylation does not account for the membrane association in neurons.


Assuntos
Neurônios/metabolismo , Prenilação de Proteína , Ubiquitina Tiolesterase/metabolismo , Animais , Apoptose , Células COS , Membrana Celular/metabolismo , Chlorocebus aethiops , Células HEK293 , Humanos , Cultura Primária de Células , Estabilidade Proteica , Estrutura Terciária de Proteína , Transporte Proteico , Ratos , Ubiquitinação
4.
Proc Natl Acad Sci U S A ; 108(49): 19772-7, 2011 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-22089239

RESUMO

The surface expression and regulated endocytosis of kainate (KA) receptors (KARs) plays a critical role in neuronal function. PKC can modulate KAR trafficking, but the sites of action and molecular consequences have not been fully characterized. Small ubiquitin-like modifier (SUMO) modification of the KAR subunit GluK2 mediates agonist-evoked internalization, but how KAR activation leads to GluK2 SUMOylation is unclear. Here we show that KA stimulation causes rapid phosphorylation of GluK2 by PKC, and that PKC activation increases GluK2 SUMOylation both in vitro and in neurons. The intracellular C-terminal domain of GluK2 contains two predicted PKC phosphorylation sites, S846 and S868, both of which are phosphorylated in response to KA. Phosphomimetic mutagenesis of S868 increased GluK2 SUMOylation, and mutation of S868 to a nonphosphorylatable alanine prevented KA-induced SUMOylation and endocytosis in neurons. Infusion of SUMO-1 dramatically reduced KAR-mediated currents in HEK293 cells expressing WT GluK2 or nonphosphorylatable S846A mutant, but had no effect on currents mediated by the S868A mutant. These data demonstrate that agonist activation of GluK2 promotes PKC-dependent phosphorylation of S846 and S868, but that only S868 phosphorylation is required to enhance GluK2 SUMOylation and promote endocytosis. Thus, direct phosphorylation by PKC and GluK2 SUMOylation are intimately linked in regulating the surface expression and function of GluK2-containing KARs.


Assuntos
Endocitose , Neurônios/metabolismo , Proteína Quinase C/metabolismo , Receptores de Ácido Caínico/metabolismo , Alanina/genética , Alanina/metabolismo , Substituição de Aminoácidos , Animais , Western Blotting , Células COS , Células Cultivadas , Chlorocebus aethiops , Células HEK293 , Humanos , Ácido Caínico/farmacologia , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Microscopia Confocal , Mutação , Neurônios/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Ratos , Ratos Wistar , Receptores de Ácido Caínico/agonistas , Receptores de Ácido Caínico/genética , Proteína SUMO-1/metabolismo , Serina/genética , Serina/metabolismo , Sumoilação/efeitos dos fármacos , Receptor de GluK2 Cainato
5.
Sci Rep ; 14(1): 10939, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740871

RESUMO

Long non-coding RNAs (lncRNAs) represent an emerging class of genes which play significant and diverse roles in human cancers. Nevertheless, the functional repertoires of lncRNAs in cancer cell subtypes remains unknown since most studies are focused on protein coding genes. Here, we explored the contribution of lncRNAs in Colorectal Cancer (CRC) heterogeneity. We analyzed 49'436 single-cells from 29 CRC patients and showed that lncRNAs are significantly more cell type specific compared to protein-coding genes. We identified 996 lncRNAs strongly enriched in epithelial cells. Among these, 98 were found to be differentially expressed in tumor samples compared to normal controls, when integrating 270 bulk CRC profiles. We validated the upregulation of two of them (CASC19 and LINC00460) in CRC cell lines and showed their involvement in CRC proliferation by CRISPR-Cas9 knock down experiments. This study highlights a list of novel RNA targets for potential CRC therapeutics, substantiated through experimental validation.


Assuntos
Neoplasias Colorretais , Regulação Neoplásica da Expressão Gênica , RNA Longo não Codificante , Transcriptoma , Humanos , RNA Longo não Codificante/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Análise de Célula Única/métodos , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Proliferação de Células/genética
6.
J Biol Chem ; 287(27): 22781-8, 2012 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-22582390

RESUMO

Homeostatic scaling allows neurons to alter synaptic transmission to compensate for changes in network activity. Here, we show that suppression of network activity with tetrodotoxin, which increases surface expression of AMPA receptors (AMPARs), dramatically reduces levels of the deSUMOylating (where SUMO is small ubiquitin-like modifier) enzyme SENP1, leading to a consequent increase in protein SUMOylation. Overexpression of the catalytic domain of SENP1 prevents this scaling effect, and we identify Arc as a SUMO substrate involved in the tetrodotoxin-induced increase in AMPAR surface expression. Thus, protein SUMOylation plays an important and previously unsuspected role in synaptic trafficking of AMPARs that underlies homeostatic scaling.


Assuntos
Endopeptidases/metabolismo , Hipocampo/fisiologia , Homeostase/fisiologia , Neurônios/fisiologia , Sumoilação/fisiologia , Sinapses/metabolismo , Animais , Cisteína Endopeptidases , Proteínas do Citoesqueleto/metabolismo , Endopeptidases/genética , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Células HEK293 , Hipocampo/citologia , Humanos , Proteínas do Tecido Nervoso/metabolismo , Plasticidade Neuronal/fisiologia , Técnicas de Cultura de Órgãos , Transporte Proteico/fisiologia , Ratos , Receptores de AMPA/metabolismo , Bloqueadores dos Canais de Sódio/farmacologia , Sumoilação/efeitos dos fármacos , Tetrodotoxina/farmacologia
7.
Phonetica ; 75(3): 187-189, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29852505
8.
Oncologist ; 17(1): 125-34, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22240540

RESUMO

BACKGROUND: The immune response of patients who have cancer, who may be receiving immunosuppressive therapy, is generally considered to be decreased. This study aimed to evaluate the immune response of cancer patients to the 2009 influenza A (H1N1) vaccine. PATIENTS AND METHODS: We conducted a prospective single site study comparing the immune response after H1N1 vaccination of healthy controls (group A), patients who had solid tumors and were taking myelosuppressive chemotherapy (group B), patients who had solid tumors and were taking nonmyelosuppressive or no treatment (group C), and patients who had hematologic malignancies (group D). RESULTS: At 2-6 weeks after vaccination, seroconversion was observed in 80.0% of group A (95% confidence interval [CI], 65.0%-89.7%), 72.2% of group B (95% CI, 55.9%-84.3%), 87.0% of group C (95% CI, 72.2%-94.7%), and 75.0% of group D (95% CI, 52.8%-89.2%) (p = NS). The geometric mean titer ratio, that is, geometric mean factor increase in antibody titer after vaccination, was 12.6 (95% CI, 7.9-19.9), 12.7 (95% CI, 7.3-22.1), 23.0 (95% CI, 13.9-38.2), and 12.1 (95% CI, 5.3-27.9) (p = NS), and the seroprotection rates were 95.5% (95% CI, 84.0%-99.6%), 79.0% (95% CI, 63.4%-89.2%), 90.5% (95% CI, 77.4%-96.8%), and 90.0% (95% CI, 71%-98.7%) in the corresponding groups (p = NS). Immune responses were robust regardless of malignancy, or time intervals between the use of myelosuppressive or immunosuppressive medications and vaccination. No participants developed clinical H1N1 infection. CONCLUSION: Cancer patients, whether taking myelosuppressive chemotherapy or not, are able to generate an immune response to the H1N1 vaccine similar to that of healthy controls.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Neoplasias/imunologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Vacinas contra Influenza/administração & dosagem , Masculino , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Estudos Prospectivos
9.
Biochem Biophys Res Commun ; 409(4): 657-62, 2011 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-21616059

RESUMO

G-protein coupled receptor interacting scaffold protein (GISP) is a multi-domain, brain-specific protein derived from the A-kinase anchoring protein (AKAP)-9 gene. Using yeast two-hybrid screens to identify GISP interacting proteins we isolated the SUMO conjugating enzyme Ubc9. GISP interacts with Ubc9 in vitro, in heterologous cells and in neurons. SUMOylation is a post-translational modification in which the small protein SUMO is covalently conjugated to target proteins, modulating their function. Consistent with its interaction with Ubc9, we show that GISP is SUMOylated by both SUMO-1 and SUMO-2 in both in vitro SUMOylation assays and in mammalian cells. Intriguingly, SUMOylation of GISP in neurons occurs in an activity-dependent manner in response to chemical LTP. These data suggest that GISP is a novel neuronal SUMO substrate whose SUMOylation status is modulated by neuronal activity.


Assuntos
Encéfalo/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Sumoilação , Proteínas de Ancoragem à Quinase A , Animais , Encéfalo/citologia , Células COS , Chlorocebus aethiops , Proteínas do Citoesqueleto , Proteínas do Tecido Nervoso/genética , Neurônios/metabolismo , Ratos , Proteína SUMO-1/metabolismo , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Técnicas do Sistema de Duplo-Híbrido , Enzimas de Conjugação de Ubiquitina/metabolismo
10.
Am J Bioeth ; 11(5): 24-30, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21534146

RESUMO

This article argues that we could improve the design of research protocols by developing an awareness of and a responsiveness to the social contexts of all the actors in the research enterprise, including subjects, investigators, sponsors, and members of the community in which the research will be conducted. "Social context" refers to the settings in which the actors are situated, including, but not limited to, their social, economic, political, cultural, and technological features. The utility of thinking about social contexts is introduced and exemplified by the presentation of a hypothetical case in which one central issue is limitation of the probability of injury to subjects by selection of individuals who are not expected to live long enough for the known risks of the study to become manifest as harms. Benefits of such considerations may include enhanced subject satisfaction and cooperation, community acceptance, and improved data quality, among other desirable consequences.


Assuntos
Experimentação Humana/ética , Meios de Comunicação de Massa , Opinião Pública , Projetos de Pesquisa , Pesquisadores , Sujeitos da Pesquisa , Meio Social , Vacinas contra a AIDS/administração & dosagem , Vacinas contra a AIDS/imunologia , Esclerose Lateral Amiotrófica/complicações , Ensaios Clínicos como Assunto/ética , Comitês de Ética em Pesquisa , Ética em Pesquisa , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , Humanos
11.
Mol Cancer Res ; 19(8): 1398-1411, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34088870

RESUMO

Recent evidence has highlighted the role of N 6-methyladenosine (m6A) in the regulation of mRNA expression, stability, and translation, supporting a potential role for posttranscriptional regulation mediated by m6A in cancer. Here, we explore prostate cancer as an exemplar and demonstrate that low levels of N 6-adenosine-methyltransferase (METTL3) is associated with advanced metastatic disease. To investigate this relationship, we generated the first prostate m6A maps, and further examined how METTL3 regulates expression at the level of transcription, translation, and protein. Significantly, transcripts encoding extracellular matrix proteins are consistently upregulated with METTL3 knockdown. We also examined the relationship between METTL3 and androgen signaling and discovered the upregulation of a hepatocyte nuclear factor-driven gene signature that is associated with therapy resistance in prostate cancer. Significantly, METTL3 knockdown rendered the cells resistant to androgen receptor antagonists via an androgen receptor-independent mechanism driven by the upregulation of nuclear receptor NR5A2/LRH-1. IMPLICATIONS: These findings implicate changes in m6A as a mechanism for therapy resistance in metastatic prostate cancer.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Metiltransferases/genética , Neoplasias da Próstata/genética , Adenosina/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Células HEK293 , Humanos , Masculino , Próstata/patologia , Receptores Androgênicos/genética , Receptores Citoplasmáticos e Nucleares/genética , Transdução de Sinais/genética , Regulação para Cima/genética
12.
Front Med (Lausanne) ; 8: 604221, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33665196

RESUMO

Background: Cancer patients may carry a worse prognosis with SARS-CoV-2 infection. Most of the previous studies described the outcomes of hospitalized cancer patients. We aimed to study the clinical factors differentiating patients requiring hospital care vs. home recovery, and the trajectory of their anti-cancer treatment. Methods: This study was conducted in a community cancer center in New York City. Eligible patients were those who had cancer history and were diagnosed of SARS-CoV-2 infection between March 1 and May 30, 2020, with confirmatory SARs-CoV-2 virus test or antibody test. Four groups were constructed: (A) hospitalized and survived, (B) hospitalized requiring intubation and/or deceased, (C) non-hospitalized, asymptomatic, with suspicious CT image findings, close exposure, or positive antibody test, and (D) non-hospitalized and symptomatic. Results: One hundred and six patients were included in the analysis. Thirty-five patients (33.0%) required hospitalization and 13 (12.3%) died. Thirty (28.3%) patients were asymptomatic and 41 (38.7%) were symptomatic and recovered at home. Comparing to patients who recovered at home, hospitalized patients were composed of older patients (median age 71 vs. 63 years old, p = 0.000299), more who received negative impact treatment (62.9 vs. 32.4%, p = 0.0036) that mostly represented myelosuppressive chemotherapy (45.7 vs. 23.9%, p = 0.0275), and more patients with poorer baseline performance status (PS ≥ 2 25.7 vs. 2.8%, p = 0.0007). Hypoxemia (35% in group A vs. 73.3% in group B, p = 0.0271) at presentation was significant to predict mortality in hospitalized patients. The median cumulative hospital stay for discharged patients was 16 days (range 5-60). The median duration of persistent positivity of SARS-CoV-2 RNA was 28 days (range 10-86). About 52.9% of patients who survived hospitalization and required anti-cancer treatment reinitiated therapy. Ninety-two percent of the asymptomatic patients and 51.7% of the symptomatic patients who recovered at home continued treatment on schedule and almost all reinitiated treatment after recovery. Conclusions: Cancer patients may have a more severe status of SARS-CoV-2 infection after receiving myelosuppressive chemotherapy. Avoidance should be considered in older patients with poor performance status. More than two thirds of patients exhibit minimal to moderate symptoms, and many of them can continue or restart their anti-cancer treatment upon recovery.

13.
Anesth Analg ; 109(6): 1847-9, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19923513

RESUMO

BACKGROUND: New reflectance pulse oximetry probes placed on the forehead may be an improvement over transmittance probes placed on a finger, toe, or earlobe in patients with compromised perfusion. We compared the reliability and accuracy of the 2 types of probes in patients undergoing vascular surgery. METHODS: Patients with peripheral vascular disease undergoing vascular surgery under general anesthesia were monitored with both a transmittance earlobe probe and a reflectance forehead probe. Spo(2) was recorded continuously from both probes, and arterial blood gas samples were analyzed when clinically indicated. The average values from both probes over each minute were compared using Bland-Altman analysis. RESULTS: Twenty patients were included yielding a total of 3993 1-min averaged data pairs. Neither probe failed to report a value for more than 1 min. A Bland-Altman plot showed the limits of agreement between the probes of -4.0% to +2.6%. Twenty-eight arterial blood samples were analyzed for 14 patients and Sao(2) closely matched both Spo(2) probe values at the time of sampling. Compared with Sao(2), analysis demonstrated limits of agreement of -4.7% to 6.1% for ear and -3.3% to 3.4% for forehead sites. CONCLUSIONS: The new reflectance forehead Spo(2) probe tested has acceptable agreement with the older transmittance probe placed on the earlobe for pulse oximetry within typical ranges of Spo(2) in patients undergoing vascular surgery.


Assuntos
Anestesia Geral , Monitorização Intraoperatória/métodos , Oximetria/métodos , Oxigênio/sangue , Doenças Vasculares Periféricas/cirurgia , Pele/irrigação sanguínea , Procedimentos Cirúrgicos Vasculares , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Orelha Externa , Testa , Hemoglobinas/metabolismo , Humanos , Pessoa de Meia-Idade , Oxiemoglobinas/metabolismo , Doenças Vasculares Periféricas/sangue , Doenças Vasculares Periféricas/fisiopatologia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Fatores de Tempo
14.
Am Psychol ; 74(6): 745, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31545646

RESUMO

This article memorializes John T. Cacioppo (1951-2018). Cacioppo was the cofounder of the field of social neuroscience and was well known for his transformative work demonstrating how social isolation and loneliness affect well-being. He was also a national leader on matters related to science and health policy. At the University of Chicago, he was the Tiffany and Margaret Blake Distinguished Service Professor of Psychology, where he served as director of the Social Psychology program and the Center for Cognitive and Social Neuroscience. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

15.
A A Pract ; 12(9): 321-324, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30431442

RESUMO

We report the perioperative course of a 75-year-old woman undergoing robotic-assisted laparoscopic hysterectomy and tumor debulking. The patient developed severe, persistent hypertension after intraoperative methylene blue administration requiring a Surgical Intensive Care Unit admission with further investigative evaluation revealing a previously undiagnosed pheochromocytoma. Our discussion focuses on the differential diagnoses for her perioperative hypertension. We evaluate whether methylene blue triggered a pheochromocytoma crisis in our patient and emphasize the caution and critical thinking we all should demonstrate while providing anesthetic care.


Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico , Hipertensão/etiologia , Azul de Metileno/efeitos adversos , Feocromocitoma/diagnóstico , Adenocarcinoma/cirurgia , Neoplasias das Glândulas Suprarrenais/cirurgia , Idoso , Procedimentos Cirúrgicos de Citorredução , Neoplasias do Endométrio/cirurgia , Feminino , Humanos , Histerectomia/efeitos adversos , Achados Incidentais , Laparoscopia/efeitos adversos , Feocromocitoma/cirurgia , Procedimentos Cirúrgicos Robóticos/efeitos adversos
16.
PLoS One ; 14(2): e0212857, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30794696

RESUMO

Protein SUMOylation regulates multiple processes involved in the differentiation and maturation of cells and tissues during development. Despite this, relatively little is known about the spatial and temporal regulation of proteins that mediate SUMOylation and deSUMOylation in the CNS. Here we monitor the expression of key SUMO pathway proteins and levels of substrate protein SUMOylation in the forebrain and cerebellum of Wistar rats during development. Overall, the SUMOylation machinery is more highly-expressed at E18 and decreases thereafter, as previously described. All of the proteins investigated are less abundant in adult than in embryonic brain. Furthermore, we show for first time that the profiles differ between cerebellum and cerebrum, indicating differential regional regulation of some of the proteins analysed. These data provide further basic observation that may open a new perspective of research about the role of SUMOylation in the development of different brain regions.


Assuntos
Cerebelo/embriologia , Cérebro/embriologia , Proteínas do Tecido Nervoso/metabolismo , Sumoilação/fisiologia , Animais , Cerebelo/citologia , Cérebro/citologia , Ratos , Ratos Wistar
17.
Sci Rep ; 7: 43811, 2017 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-28262828

RESUMO

The GTPase dynamin-related protein 1 (Drp1) is essential for physiological and pathophysiological mitochondrial fission. DeSUMOylation of Drp1 by the enzyme SENP3 promotes cell death during reperfusion after ischaemia by enhancing Drp1 partitioning to the mitochondrial outer membrane (MOM), which causes cytochrome c release and apoptosis. However, how deSUMOylation recruits Drp1 to the MOM is unknown. Here we show that deSUMOylation selectively promotes Drp1 binding to the MOM resident adaptor protein mitochondrial fission factor (Mff). Consistent with this, preventing Drp1 SUMOylation by mutating the SUMO acceptor sites enhances binding to Mff. Conversely, increasing Drp1 SUMOylation by knocking down SENP3 reduces both Drp1 binding to Mff and stress-induced cytochrome c release. Directly tethering Drp1 to the MOM bypasses the need for Mff to evoke cytochrome c release, and occludes the effect of SENP3 overexpression. Thus, Drp1 deSUMOylation promotes cell death by enhancing Mff-mediated mitochondrial recruitment. These data provide a mechanistic explanation for how the SUMOylation status of Drp1 acts as a key switch in cell death/survival decisions following extreme cell stress.


Assuntos
Apoptose , Cisteína Endopeptidases/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Mitocondriais/metabolismo , Cisteína Endopeptidases/genética , Citocromos c/metabolismo , Dinaminas , GTP Fosfo-Hidrolases/genética , Células HEK293 , Células HeLa , Humanos , Proteínas de Membrana/genética , Proteínas Associadas aos Microtúbulos/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Ligação Proteica , Interferência de RNA , Sumoilação
18.
Semin Radiat Oncol ; 16(2): 120-30, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16564447

RESUMO

"Suddenly a solitary horseman appeared on the horizon, then another, then another...in a few moments a whole crowd of horsemen swooped down upon him."-Leacock The illusion of solitary metastases is counterintuitive but has generated a sizable literature on the subject. The reality is that there are more metastatic deaths each year than the total number of true long-term survivors of solitary metastases combining all organ sites in the literature of the past century up to the present time. The largest number of solitary metastases survivors had metastases primarily in the lung and/or liver. With innovations in molecular imaging and advances in molecular oncology, the stage is set to detect truly solitary metastases early. Then, aggressive treatment by surgical excision, stereotactic body radiosurgery, targeted chemotherapy, or immunotherapy could eradicate the lesion. A comprehensive review of solitary metastases in a large variety of anatomic sites is presented. A broader staging system is recommended to encompass a solitary metastasis (M1) and oligometastases (M2) as distinct from multiple metastases (M3).


Assuntos
Metástase Neoplásica/patologia , Biomarcadores Tumorais/análise , Neoplasias Ósseas/secundário , Neoplasias Encefálicas/secundário , Humanos , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/secundário , Metástase Neoplásica/diagnóstico , Metástase Neoplásica/terapia , Estadiamento de Neoplasias , Técnicas Estereotáxicas , Irradiação Corporal Total
19.
Int J Radiat Oncol Biol Phys ; 64(4): 1162-7, 2006 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-16427211

RESUMO

PURPOSE: We examined overall and disease-specific survival outcomes both from the time of initial treatment and from the start of salvage hormone therapy (HT), by the extent of disease progression at the time salvage HT was started in patients treated on RTOG Protocol 86-10. METHODS: [corrected] With a median follow-up of 9.0 years, 247 patients (54%) had received subsequent salvage HT. The overall survival (OVS) and disease-specific survival (DSS) were compared by the extent of disease progression at the time salvage HT was started. RESULTS: For those patients with distant metastases (DM) present at the start of salvage HT, the OVS and DSS were significantly reduced when compared to [corrected] those with DM absent at the time salvage HT was started (OVS at 8 years, 31% vs. 58%; DSS at 8 years, 38% vs. 65%). A statistically significant increase in DSS was observed among the 143 patients with DM absent when patients with prostate-specific antigen (PSA) less than 20 were compared with those with PSA greater than 20 at the time salvage HT was started. CONCLUSION: [corrected] The DSS and the OVS of the relapsed patient are decreased in those with more extensive disease at the time of salvage HT. However, because this protocol could not evaluate the effect of posttreatment PSA velocity on outcomes, which is likely a better predictor of long-term success with salvage HT, these results cannot be taken to demonstrate that early salvage HT in patients with long posttreatment PSA doubling times is necessary for longer survival.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Flutamida/uso terapêutico , Gosserrelina/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Terapia de Salvação/métodos , Análise de Variância , Antagonistas de Androgênios/efeitos adversos , Antineoplásicos Hormonais/efeitos adversos , Intervalo Livre de Doença , Flutamida/efeitos adversos , Gosserrelina/efeitos adversos , Humanos , Masculino , Modelos de Riscos Proporcionais , Antígeno Prostático Específico , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Falha de Tratamento
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