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1.
Bioorg Med Chem Lett ; 28(13): 2289-2293, 2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29807796

RESUMO

TRAP1 (Hsp75) is the mitochondrial paralog of the Hsp90 molecular chaperone family. Due to structural similarity among Hsp90 chaperones, a potential strategy to induce apoptosis through mitochondrial TRAP1 ATPase inhibition has been envisaged and a series of compounds has been developed by binding the simple pharmacophoric core of known Hsp90 inhibitors with various appendages bearing a permanent cationic head, or a basic group highly ionizable at physiologic pH. Cationic appendages were selected as vehicles to deliver drugs to mitochondria. Indeed, masses of new derivatives were evidenced to accumulate in the mitochondrial fraction from colon carcinoma cells and a compound in the series, with a guanidine appendage, demonstrated good activity in inhibiting recombinant TRAP1 ATPase and cell growth and in inducing apoptotic cell death in colon carcinoma cells.


Assuntos
Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Isoxazóis/farmacologia , Mitocôndrias/metabolismo , Adenosina Trifosfatases/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Guanidinas/síntese química , Guanidinas/química , Guanidinas/farmacologia , Células HCT116 , Humanos , Isoxazóis/síntese química , Isoxazóis/química , Estrutura Molecular , Oniocompostos/síntese química , Oniocompostos/química , Oniocompostos/farmacologia , Compostos Organofosforados/síntese química , Compostos Organofosforados/química , Compostos Organofosforados/farmacologia , Compostos de Piridínio/síntese química , Compostos de Piridínio/química , Compostos de Piridínio/farmacologia
2.
Cancer Radiother ; 27(8): 725-730, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37777371

RESUMO

Whole brain reirradiation for the treatment of multiple brain metastases has shown promising results. However, concerns remain over the possible neurotoxic effects of the cumulative dose as well as the questionable radiosensitivity of recurrent metastases. A second reirradiation of the whole brain is ordinarily performed in our department for palliative purposes in patients presenting with multiple metastatic brain progression. For this study, an investigational third whole brain reirradiation has been administered to highly selected patients to obtain disease control and delay progression. Clinical outcomes and neurological toxicity were also evaluated.


Assuntos
Neoplasias Encefálicas , Radiocirurgia , Reirradiação , Humanos , Neoplasias Encefálicas/secundário , Irradiação Craniana/efeitos adversos , Irradiação Craniana/métodos , Estudos Retrospectivos , Encéfalo , Radiocirurgia/métodos
3.
Biochim Biophys Acta ; 1816(1): 13-24, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21371531

RESUMO

An unknown primary tumor (UPT) is defined by the presence of a metastatic cancer without a known primary site of origin despite a standardized diagnostic workup. Clinically, UPTs show rapid progression and early dissemination, with signs and symptoms related to the metastatic site. The molecular bases of their biology remain largely unknown, with no evidence as to whether they represent a distinct biological entity. Immunohistochemistry remain the best diagnostic tool in term of cost-effectiveness, but the time-consuming "algorithmic process" it relies on has led to the application of new molecular techniques for the identification of the primary site of UPTs. For example, several microarray or miRNA classifications of UPTs have been used, with an accuracy in the prediction of the primary site as high as 90%. It should be noted that validating a prediction of tissue origin is challenging in these patients, since most of them will never have a primary site identified. Moreover, prospective studies to determine whether selection of treatment options based on such profiling methods actually improves patient outcome are still missing. In the last few years functional imaging (i.e. FDG-PET/CT) has gained a main role in the detection of the site of origin of UPTs and is currently recommended by the European Association of Nuclear Medicine. However, despite recent refinements in the diagnostic workup, the site of origin of UPT often remains elusive. As a consequence, treatment of patients with UPT is still empirical and inadequate.


Assuntos
Neoplasias Primárias Desconhecidas/genética , Animais , Perfilação da Expressão Gênica , Humanos , MicroRNAs/análise , Neoplasias Primárias Desconhecidas/diagnóstico , Neoplasias Primárias Desconhecidas/patologia , Neoplasias Primárias Desconhecidas/terapia
5.
Biomed Res Int ; 2016: 1295329, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27563661

RESUMO

Patients with hepatocellular carcinoma (HCC) comply with an advanced disease and are not eligible for radical therapy. In this distressed scenario new treatment options hold great promise; among them transarterial chemoembolization (TACE) and transarterial metabolic radiotherapy (TAMR) have shown efficacy in terms of both tumor shrinking and survival. External radiation therapy (RTx) by using novel three-dimensional conformal radiotherapy has also been used for HCC patients with encouraging results while its role had been limited in the past for the low tolerance of surrounding healthy liver. The rationale of TAMR derives from the idea of delivering exceptional radiation dose locally to the tumor, with cell killing intent, while preserving normal liver from undue exposition and minimizing systemic irradiation. Since the therapeutic efficacy of TACE is being continuously disputed, the TAMR with (131)I Lipiodol or (90)Y microspheres has gained consideration providing adequate therapeutic responses regardless of few toxicities. The implementation of novel radioisotopes and technological innovations in the field of RTx constitutes an intriguing field of research with important translational aspects. Moreover, the combination of different therapeutic approaches including chemotherapy offers captivating perspectives. We present the role of the radiation-based therapies in hepatocellular carcinoma patients who are not entitled for radical treatment.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Quimiorradioterapia/métodos , Neoplasias Hepáticas/terapia , Carcinoma Hepatocelular/patologia , Humanos , Fígado/patologia , Neoplasias Hepáticas/patologia
6.
Cell Death Differ ; 23(9): 1542-54, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27206315

RESUMO

Tumour cells have long been considered defective in mitochondrial respiration and mostly dependent on glycolytic metabolism. However, this assumption is currently challenged by several lines of evidence in a growing number of tumours. Ovarian cancer (OC) is one of the most lethal cancers worldwide, but it continues to be a poorly understood disease and its metabolic features are far to be elucidated. In this context, we investigated the role of tumour necrosis factor receptor-associated protein 1 (TRAP1), which is found upregulated in several cancer types and is a key modulator of tumour cell metabolism. Surprisingly, we found that TRAP1 expression inversely correlated with grade, stage and lower survival in a large cohort of OC patients. Accordingly, TRAP1 silencing induced resistance to cisplatin, resistant cells showed increased oxidative metabolism compared with their sensitive counterpart, and the bioenergetics cellular index of higher grade tumours indicated increased mitochondrial respiration. Strikingly, cisplatin resistance was reversible upon pharmacological inhibition of mitochondrial oxidative phosphorylation by metformin/oligomycin. At molecular level, increased oxidative metabolism in low TRAP1-expressing OC cells and tissues enhanced production of inflammatory mediators such as interleukin (IL)-6 and IL-8. Mechanistically, we identified members of the multidrug resistance complex (MDR) as key mediators of such metabolism-driven, inflammation-induced process. Indeed, treatment of OC cell lines with TNFα and IL6 induced a selective increase in the expression of TAP1 and multidrug resistance protein 1, whereas TAP1 silencing sensitized cells to cisplatin-induced apoptosis. Our results unveil a novel role for TRAP1 and oxidative metabolism in cancer progression and suggest the targeting of mitochondrial bioenergetics to increase cisplatin efficacy in human OC.


Assuntos
Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Inflamação/patologia , Neoplasias Ovarianas/tratamento farmacológico , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Intervalo Livre de Doença , Feminino , Glicólise , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Inflamação/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Metformina/farmacologia , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Fosforilação Oxidativa/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo
7.
FEBS Lett ; 403(2): 131-5, 1997 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-9042952

RESUMO

Mitochondrial superoxide dismutase (MnSOD) is usually diminished in cancer cells. We observed that in vivo treatment with LPS produces a strong increase of MnSOD mRNA levels and a weak induction of an inactive protein in rat hepatocarcinomas. In normal liver iron deficiency, obtained with desferrioxamine administration, produces a decrease in the MnSOD induction by LPS, indicating that such induction could depend on tissue iron content. However, no change in MnSOD mRNA has been observed in iron-overloaded tumor tissue. Thus, iron is possibly involved in the transcriptional regulation of the protein, in combination with some other unknown factor that appears to be deficient in tumor cells.


Assuntos
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Ferro/farmacologia , Lipopolissacarídeos/farmacologia , Superóxido Dismutase/genética , Animais , Desferroxamina/farmacologia , Fígado/efeitos dos fármacos , Fígado/enzimologia , Neoplasias Hepáticas Experimentais/enzimologia , Neoplasias Hepáticas Experimentais/patologia , Transplante de Neoplasias , Ratos , Ratos Endogâmicos
8.
Oncol Rep ; 7(6): 1305-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11032934

RESUMO

5-Fluorouracil (5-FU) is the main drug used in the treatment of advanced gastric cancer. Combination chemotherapy is not always superior to 5-FU alone, especially when biomodulators are also administered. In an attempt to exploit all the cytotoxic mechanisms of 5-FU, we carried out a pilot study with a double route of administration of 5-FU (intravenous bolus and continuous infusion) and a multiple modulation of 5-FU by methotrexate (MTX), 6S-leucovorin (6S-LV) and cisplatin (CDDP). A group of 30 patients affected by advanced gastric cancer was treated with MTX 50 mg/m2 and 5-FU 400 mg/m2 as an i.v. bolus on day 1, followed by a 5 day i. v. continuous infusion of 5-FU 600 mg/m2/day and 6S-LV 100 mg/m2/day; on day 3 CDDP 100 mg/m2 was also administered. The regimen was repeated every 4 weeks. Six partial responses (20+/-14. 3%), 12 stable diseases (40+/-17.5%) and 12 progression (40+/-17.5%) were observed in an intent-to-treat analysis. Median survival was 7 months. All responding patients had performance status 0-1. Grade 3-4 toxicity was mainly gastrointestinal, but grade 3-4 anemia and leucopenia were also recorded. The schedule has low activity. The use of different modulators and way of administration of 5-FU does not provide advantages in advanced gastric cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Esquema de Medicação , Sinergismo Farmacológico , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Infusões Intravenosas , Leucovorina/administração & dosagem , Leucovorina/efeitos adversos , Masculino , Metotrexato/administração & dosagem , Metotrexato/efeitos adversos , Pessoa de Meia-Idade , Projetos Piloto , Neoplasias Gástricas/patologia
9.
Resuscitation ; 55(3): 247-54, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12458061

RESUMO

BACKGROUND: The aim of this research is to evaluate quality of out-of-hospital medical services in our country, using performance indicators and a new computerised database. METHODS: (a) EXPERIMENTAL DESIGN: Data were collected prospectively in three emergency dispatch centres for 90 days. Follow-up was evaluated at 1 day and 1 month after the event. This paper presents data on the cardiac arrest cohort only. (b) SETTING: Three emergency dispatch centres in Lombardia. (c) PATIENTS: One hundred and seventy-eight patients in non-traumatic cardiac arrest were enrolled. (d) INTERVENTIONS: None. The study was observational only. RESULTS: Mean interval between phone call and arrival on scene was 8.5+/-3.5 min. BLS manoeuvres were carried out from bystanders only in 15% of the cohort; this was associated with significant mortality reduction (85.7 versus 95.8%, chi(2) P<0.05). One hundred and thirty-three patients (75%) received assistance from BLS crews while only 45 patients (25%) were assisted by ALS medical personel, with a significant mortality reduction (ALS deaths 86.7%, BLS deaths 97%). Total 24 h survival was 9% and survival at 1 month declined to 6.17%. CONCLUSIONS: Quality monitoring produces objective information on interventions and outcomes. Only with this information, is it possible to implement improvement programmes that are planned according to the data presented.


Assuntos
Reanimação Cardiopulmonar/normas , Serviços Médicos de Emergência/normas , Parada Cardíaca/terapia , Avaliação de Resultados em Cuidados de Saúde , Idoso , Idoso de 80 Anos ou mais , Sistemas de Comunicação entre Serviços de Emergência , Feminino , Parada Cardíaca/mortalidade , Humanos , Itália/epidemiologia , Masculino , Estudos Prospectivos , Qualidade da Assistência à Saúde , Taxa de Sobrevida
10.
Cell Death Dis ; 4: e851, 2013 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-24113185

RESUMO

TNF receptor-associated protein 1 (TRAP1), the main mitochondrial member of the heat shock protein (HSP) 90 family, is induced in most tumor types and is involved in the regulation of proteostasis in the mitochondria of tumor cells through the control of folding and stability of selective proteins, such as Cyclophilin D and Sorcin. Notably, we have recently demonstrated that TRAP1 also interacts with the regulatory protein particle TBP7 in the endoplasmic reticulum (ER), where it is involved in a further extra-mitochondrial quality control of nuclear-encoded mitochondrial proteins through the regulation of their ubiquitination/degradation. Here we show that TRAP1 is involved in the translational control of cancer cells through an attenuation of global protein synthesis, as evidenced by an inverse correlation between TRAP1 expression and ubiquitination/degradation of nascent stress-protective client proteins. This study demonstrates for the first time that TRAP1 is associated with ribosomes and with several translation factors in colon carcinoma cells and, remarkably, is found co-upregulated with some components of the translational apparatus (eIF4A, eIF4E, eEF1A and eEF1G) in human colorectal cancers, with potential new opportunities for therapeutic intervention in humans. Moreover, TRAP1 regulates the rate of protein synthesis through the eIF2α pathway either under basal conditions or under stress, favoring the activation of GCN2 and PERK kinases, with consequent phosphorylation of eIF2α and attenuation of cap-dependent translation. This enhances the synthesis of selective stress-responsive proteins, such as the transcription factor ATF4 and its downstream effectors BiP/Grp78, and the cystine antiporter system xCT, thereby providing protection against ER stress, oxidative damage and nutrient deprivation. Accordingly, TRAP1 silencing sensitizes cells to apoptosis induced by novel antitumoral drugs that inhibit cap-dependent translation, such as ribavirin or 4EGI-1, and reduces the ability of cells to migrate through the pores of transwell filters. These new findings target the TRAP1 network in the development of novel anti-cancer strategies.


Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Proteínas de Choque Térmico/metabolismo , Biossíntese de Proteínas , Estresse Fisiológico , Fator 1 Associado a Receptor de TNF/metabolismo , Neoplasias Colorretais/genética , Regulação para Baixo , Chaperona BiP do Retículo Endoplasmático , Fator de Iniciação 2 em Eucariotos/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Ligação Proteica , Proteólise , Ribossomos/metabolismo , Transdução de Sinais , Ubiquitinação
11.
Cell Death Differ ; 19(4): 592-604, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21979464

RESUMO

Tumor necrosis factor receptor-associated protein-1 (TRAP1) is a mitochondrial (MITO) antiapoptotic heat-shock protein. The information available on the TRAP1 pathway describes just a few well-characterized functions of this protein in mitochondria. However, our group's use of mass-spectrometric analysis identified TBP7, an AAA-ATPase of the 19S proteasomal subunit, as a putative TRAP1-interacting protein. Surprisingly, TRAP1 and TBP7 colocalize in the endoplasmic reticulum (ER), as demonstrated by biochemical and confocal/electron microscopic analyses, and interact directly, as confirmed by fluorescence resonance energy transfer analysis. This is the first demonstration of TRAP1's presence in this cellular compartment. TRAP1 silencing by short-hairpin RNAs, in cells exposed to thapsigargin-induced ER stress, correlates with upregulation of BiP/Grp78, thus suggesting a role of TRAP1 in the refolding of damaged proteins and in ER stress protection. Consistently, TRAP1 and/or TBP7 interference enhanced stress-induced cell death and increased intracellular protein ubiquitination. These experiments led us to hypothesize an involvement of TRAP1 in protein quality control for mistargeted/misfolded mitochondria-destined proteins, through interaction with the regulatory proteasome protein TBP7. Remarkably, expression of specific MITO proteins decreased upon TRAP1 interference as a consequence of increased ubiquitination. The proposed TRAP1 network has an impact in vivo, as it is conserved in human colorectal cancers, is controlled by ER-localized TRAP1 interacting with TBP7 and provides a novel model of the ER-mitochondria crosstalk.


Assuntos
Neoplasias Colorretais/metabolismo , Estresse do Retículo Endoplasmático , Retículo Endoplasmático/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas de Neoplasias/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitinação , ATPases Associadas a Diversas Atividades Celulares , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Retículo Endoplasmático/genética , Retículo Endoplasmático/patologia , Chaperona BiP do Retículo Endoplasmático , Inativação Gênica , Proteínas de Choque Térmico HSP90/genética , Humanos , Proteínas Mitocondriais/genética , Proteínas de Neoplasias/genética , Complexo de Endopeptidases do Proteassoma/genética , Dobramento de Proteína
12.
Minerva Anestesiol ; 77(3): 313-22, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21441886

RESUMO

BACKGROUND: Non-invasive ventilation (NIV) is increasingly utilized for patients with acute respiratory failure (ARF). The shortage of Intensive Care Unit (ICU) beds, a growing confidence with the technique, and the opportunity to treat ARF in a more responsive phase lead to the application of NIV outside of the ICU. The Study Group on Emergency of the Italian Society of Anesthesia, Analgesia, Resuscitation and Intensive Care (SIAARTI) promoted a national survey to collect data on NIV use outside of the ICU. METHODS: An anonymous questionnaire was developed, focusing on the location and modalities of NIV treatments, organizational and technical aspects, monitoring, estimated outcomes, the presence of protocols, and complications. The questionnaire was mailed to all members of the Scientific Society. RESULTS: Forty-six respondents were from 46 hospitals. Thirty-seven (80%) respondents applied NIV in the Emergency Department and/or General Wards. In the majority of hospitals (72%), training preceded NIV introduction. NIV could be applied in all ordinary wards in 28% of the hospitals. Patients remained in their ward in 89% of the hospitals, and a protocol was present in 70% of the hospitals. Monitoring was usually limited to continuous pulse-oxymetry and EKG; 18% of respondents did not have a monitoring standard. Reported complications and practical problems were potentially severe. Few hospitals (15%) collected data on NIV treatments. The efficacy of NIV was perceived as low, as 73% of respondents estimated that NIV avoided tracheal intubation in less than half of the treated patients. CONCLUSION: In Italy, NIV is extensively applied in non-intensive wards, and its use is not free from criticalities and contradictions. Further prospective studies and possibly guidelines are needed.


Assuntos
Respiração Artificial/estatística & dados numéricos , Contraindicações , Cuidados Críticos , Eletrocardiografia , Pesquisas sobre Atenção à Saúde , Hospitais/estatística & dados numéricos , Humanos , Itália , Monitorização Fisiológica , Oximetria , Respiração Artificial/efeitos adversos , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapia , Inquéritos e Questionários
14.
Stress ; 10(4): 342-50, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17853063

RESUMO

TRAP-1 is a mitochondrial heat shock protein (HSP), recently identified in Saos-2 osteosarcoma cells adapted to mild oxidative stress induced by diethylmaleate (DEM). TRAP-1 mRNA expression is increased in DEM-adapted cells as well as in tumor cells resistant to 5-fluorouracil and to platin derivatives. Since a strong decrease of TRAP-1 protein levels, upon cisplatin treatment, is observed only in controls but not in the DEM-adapted counterpart, a possible role for this protein in the development of resistant phenotypes could be hypothesized. To characterize the protective role of TRAP-1 against oxidative stress and apoptosis, stable transfectants were generated and characterized for their response to different stress types. These stable clones expressing constitutively high TRAP-1 levels: (i) are more resistant to H2O2-induced DNA damage and to apoptosis by cisplatin; (ii) contain higher reduced glutathione (GSH) levels than control cells; and (iii) do not release the apoptosis-inducing factor into the nucleus upon cisplatin treatment. Furthermore, high TRAP-1 levels interfere with caspase 3 activation. These results confirm the anti-apoptotic role of TRAP-1, and suggest that increased expression of this mitochondrial HSP in DEM-adapted and chemoresistant cells could be part of a pro-survival signaling pathway aimed to evade toxic effects of oxidants and anticancer drugs.


Assuntos
Apoptose , Proteínas de Choque Térmico HSP90/fisiologia , Estresse Oxidativo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Cisplatino/farmacologia , Ensaio Cometa , Resistencia a Medicamentos Antineoplásicos , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Proteínas Mitocondriais/metabolismo , Modelos Biológicos , Osteossarcoma/patologia , Espécies Reativas de Oxigênio , Sais de Tetrazólio/farmacologia , Tiazóis/farmacologia
15.
Br J Cancer ; 96(1): 21-8, 2007 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-17164761

RESUMO

Several schedules of 5-fluorouracil (FU) and irinotecan (IRI) have been shown to improve overall survival in advanced colorectal cancer (CRC). Preclinical evidence suggests that the sequential administration of IRI and FU produces synergistic activity, although their clinical use has not been fully optimised. We investigated the interaction between short-term exposure to SN-38, the active metabolite of IRI, and prolonged exposure to FU in human CRC HT-29 cells and observed that the synergism of action between the two agents can be increased by extending the time of cell exposure to FU and reducing the interval between administration of the two agents. Based on these findings, we performed a phase I trial in 25 advanced CRC patients using a modified IRI/FU regimen as first-line therapy and evaluated three dose levels of IRI (150-300 mg/m(2)) and two of continuous infusion of FU (800-1000 mg/m(2)) in a 3-weekly schedule. The most severe grade III-IV toxicities were neutropoenia in four cycles and diarrhoea in three. One patient achieved complete response (4%), 12 a partial response (48%), the overall response rate was 52% (+/-20, 95% CI); seven of 25 patients had stable disease (28%), the overall disease control was 80% (+/-16, 95% CI). This modified IRI/FU schedule is feasible and exhibits potentially interesting clinical activity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Camptotecina/análogos & derivados , Neoplasias Colorretais/tratamento farmacológico , Fluoruracila/administração & dosagem , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Apoptose/efeitos dos fármacos , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Camptotecina/farmacologia , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quimioterapia Adjuvante , Estudos de Coortes , Progressão da Doença , Relação Dose-Resposta a Droga , Esquema de Medicação , Sinergismo Farmacológico , Estudos de Viabilidade , Feminino , Fluoruracila/efeitos adversos , Fluoruracila/farmacologia , Células HT29 , Humanos , Infusões Intravenosas , Irinotecano , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Recidiva , Resultado do Tratamento
16.
J Neurooncol ; 80(3): 251-9, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16773219

RESUMO

S100 proteins are Ca(2+)-binding polypeptides involved in the tumourigenesis of several human neoplasms. S100A13 is a key regulator of the stress-dependent release of FGF1, the prototype of the FGF protein family involved in angiogenesis. Indeed, S100A13 is a copper binding protein able to enhance the export of FGF1 in response to stress in vitro and to induce the formation of a multiprotein aggregate responsible for FGF1 release. We investigated the expression of S100A13 in human astrocytic gliomas in relation to tumour grading and vascularization. A series of 26 astrocytic gliomas was studied to evaluate microvessel density and to assess FGF1, S100A13 and VEGF-A expression. FGF1 was equally expressed in the vast majority of tumours, whereas S100A13 and VEGF-A were significantly up-regulated in high-grade vascularized gliomas. Moreover, both S100A13 and VEGF-A expression significantly correlated with microvessel density and tumour grading. These data suggest that the up-regulation of S100A13 and VEGF-A expression correlates with the activation of angiogenesis in high-grade human astrocytic gliomas.


Assuntos
Astrocitoma/irrigação sanguínea , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/irrigação sanguínea , Neovascularização Patológica/metabolismo , Proteínas S100/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Idoso , Astrocitoma/metabolismo , Neoplasias Encefálicas/metabolismo , Feminino , Fatores de Crescimento de Fibroblastos/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Regulação para Cima
17.
Biochem Biophys Res Commun ; 195(2): 697-703, 1993 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-7690559

RESUMO

In the present paper we report the production of a monoclonal antibody against rat MnSOD, a supposed tumor-suppressor protein, using a purified synthetic peptide encompassing amino acids 184-198 to immunize mice, without conjugation to a carrier. The resulting antibody is able to recognize the native form of the protein, since it can immunoprecipitate the MnSOD activity in rat liver homogenate. In Western blot studies, the antibody recognizes a protein of 24 KD M(r), whose concentration varies according to the MnSOD activity and it apparently recognizes also human and mouse MnSODs. The protocol of immunization gives high yield of secreting lines. This monoclonal antibody will allow the detection of structural and functional alterations of MnSOD.


Assuntos
Anticorpos Monoclonais/imunologia , Neoplasias Hepáticas Experimentais/enzimologia , Mitocôndrias Hepáticas/enzimologia , Superóxido Dismutase/análise , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/isolamento & purificação , Western Blotting/métodos , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Epitopos/análise , Humanos , Hibridomas , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C/imunologia , Dados de Sequência Molecular , Oligopeptídeos/imunologia , Ratos , Ratos Endogâmicos ACI , Ratos Endogâmicos BUF , Ratos Wistar , Superóxido Dismutase/imunologia , Superóxido Dismutase/metabolismo , Linfócitos T/imunologia
18.
Biochem Mol Biol Int ; 33(1): 107-15, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8081200

RESUMO

MnSOD is an antioxidant enzyme whose decrease in activity appears involved in tumorigenesis. We had previously reported the production of a monoclonal antibody, named 35.8, against rat MnSOD. In the present paper we show that it recognizes human and mouse MnSODs, although with different detection limits. We also use the antibody for immunofluorescence studies and observed that the antibody yields a positive staining of a non-nuclear protein, in rat and human organs where high concentration of MnSOD activity have been reported, and a lack of staining in rat kidney where MnSOD activity is decreased. Two tumors, an experimental rat hepatocarcinoma and a human liver metastasis from a gastrointestinal adenocarcinoma, are found negative for immunostaining.


Assuntos
Anticorpos Monoclonais/imunologia , Rim/enzimologia , Superóxido Dismutase/análise , Adenocarcinoma/induzido quimicamente , Adenocarcinoma/enzimologia , Adenocarcinoma/secundário , Sequência de Aminoácidos , Animais , Especificidade de Anticorpos , Western Blotting , Neoplasias Gastrointestinais/enzimologia , Humanos , Fígado/enzimologia , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/enzimologia , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Miocárdio/enzimologia , Ratos , Ratos Wistar
19.
J Biol Chem ; 276(7): 5147-51, 2001 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-11087725

RESUMO

Interleukin (IL)1alpha mediates proinflammatory events through its extracellular interaction with the IL1 type I receptor. However, IL1alpha does not contain a conventional signal peptide sequence that provides access to the endoplasmic reticulum-Golgi apparatus for secretion. Thus, we have studied the release of the precursor (p) and mature (m) forms of IL1alpha from NIH 3T3 cells. We have demonstrated that mIL1alpha but not pIL1alpha was released in response to heat shock with biochemical and pharmacological properties similar to those reported for the stress-mediated release pathway utilized by fibroblast growth factor (FGF)1. However, unlike the FGF1 release pathway, the IL1alpha release pathway appears to function independently of synaptotagmin (Syt)1 because the expression of a dominant-negative form of Syt1, which represses the release of FGF1, did not inhibit the release of mIL1alpha in response to temperature stress. Interestingly, whereas the expression of both mIL1alpha and FGF1 in NIH 3T3 cells did not impair the stress-induced release of either polypeptide, the expression of both pIL1alpha and FGF1 repressed the release of FGF1 in response to temperature stress. These data suggest that the release of mIL1alpha requires proteolytic processing of its precursor form and that mIL1alpha and FGF1 may utilize similar but distinct mechanisms for export.


Assuntos
Proteínas de Ligação ao Cálcio , Fator 2 de Crescimento de Fibroblastos/metabolismo , Resposta ao Choque Térmico , Interleucina-1/fisiologia , Precursores de Proteínas/fisiologia , Células 3T3 , Aminopiridinas/farmacologia , Animais , Brefeldina A/farmacologia , Desoxiglucose/farmacologia , Fator 1 de Crescimento de Fibroblastos , Interleucina-1/genética , Interleucina-1/metabolismo , Cinética , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Transporte Proteico , Deleção de Sequência , Sinaptotagmina I , Sinaptotagminas , Transfecção
20.
Growth Factors ; 18(4): 277-85, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11519826

RESUMO

The signal peptide-less FGF gene family prototype, FGF1 is released in response to temperature stress in vitro as a latent reducing agent-sensitive homodimer non-covalently complexed with the extravesicular p40 domain of p65 synaptotagmin (Syt)1. Because FGF1 is well recognized as an angiogenesis factor in vivo and angiogenesis is known to be induced by hypoxia, we examined the release of FGF1 and p40 Syt1 under conditions of hypoxia and temperature stress using a chemostatic microcarrier cell culture system. We report that like the pathway used by FGF1 and p40 Syt1 release under temperature stress, hypoxia also induces the release of FGF1 and p40 Syt1 with similar kinetic and pharmacologic properties including the requirement for functional cysteine residues. Lastly, FGF1 and p40 Syt1 release in response to hypoxia and temperature stress is sensitive to lipoxygenase and cyclooxygenase inhibitors suggesting that arachidonic acid metabolism may play an important role in the mechanism of FGF1 release in vitro.


Assuntos
Proteínas de Ligação ao Cálcio , Hipóxia Celular/fisiologia , Fator 1 de Crescimento de Fibroblastos/metabolismo , Células 3T3 , Ácido 5,8,11,14-Eicosatetrainoico/farmacologia , Aminopiridinas/farmacologia , Animais , Ácido Araquidônico/metabolismo , Linhagem Celular , Inibidores de Ciclo-Oxigenase/farmacologia , Cisteína/química , Dimerização , Fator 1 de Crescimento de Fibroblastos/química , Fator 1 de Crescimento de Fibroblastos/genética , Humanos , Inibidores de Lipoxigenase/farmacologia , Substâncias Macromoleculares , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/metabolismo , Camundongos , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/metabolismo , Nitrobenzenos/farmacologia , Estresse Fisiológico/fisiopatologia , Sulfonamidas/farmacologia , Sinaptotagmina I , Sinaptotagminas , Temperatura , Transfecção
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