Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 15 de 15
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Oncol Res Treat ; 45(10): 588-597, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35882183

RESUMO

INTRODUCTION: Pancreatic cancer (PC) represents an unfavorable prognosis condition, even in patients with resectable disease. The aim of this series was to investigate the role of treatment intensification with adjuvant chemoradiation (CRT) in radically resected PC patients. METHODS: Data from PC patients who underwent radical surgery, adjuvant chemotherapy (CT), and CRT throughout a 20-year period were retrospectively collected. Actuarial local control (LC) and the overall survival (OS) were the primary endpoints, with disease-free survival and metastasis-free survival (MFS) representing secondary endpoints. RESULTS: The analysis included 108 PC patients treated with adjuvant CRT and CT from January 2000 to August 2019. Median age was 66 years (range: 40-83), and all patients underwent radical surgical resection with adjuvant CT (88, 81.5%) plus concomitant CRT (101, 93.5%) or radiotherapy alone (7, 6.5%). The median dose delivered to the tumor bed was 50.4 Gy (range: 45-50.6 Gy), while median dose to regional lymphatic drainage stations was 39.6 Gy (range 39.6-45 Gy). Concomitant CT was a gemcitabine-based regimen in the vast majority of patients (87, 80.6%). Median follow-up time was 21 months; the 2- and 5-year LC rates were 75.8% and 59.1%, respectively. Perineural invasion at pathological assessment was found significantly associated with LC (p = 0.028). Median OS was 40 months with 2- and 5-year OS rates of 73.9% and 41.6%, respectively. CONCLUSIONS: The outcomes of this series suggest to investigate the possible impact of adding adjuvant CRT to CT in PC patients. Timing and combination of modern CRT with new systemic therapies need to be further investigated to personalize therapy and optimize clinical advantages.


Assuntos
Neoplasias Pancreáticas , Idoso , Quimiorradioterapia Adjuvante , Quimioterapia Adjuvante , Fluoruracila , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Estudos Retrospectivos , Neoplasias Pancreáticas
2.
Ther Adv Med Oncol ; 12: 1758835920940887, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32782488

RESUMO

BACKGROUND: Systemic chemotherapy for pancreatic adenocarcinoma (PDAC) and cholangiocarcinoma (CC) with peritoneal metastases (PM) is affected by several pharmacological shortcomings and low clinical efficacy. Pressurized intraperitoneal aerosol chemotherapy (PIPAC) is expected to maximize exposure of peritoneal nodules to antiblastic agents. This study aims to evaluate safety and efficacy of PIPAC for PM of PDAC and CC origin. METHODS: This is a retrospective analysis of consecutive PDAC and CC cases with PM treated with PIPAC at two European referral centers for peritoneal disease. We prospectively recorded from August 2016 to May 2019 demographic, clinical, surgical, and oncological data. We performed a feasibility and safety assessment and an efficacy analysis based on clinical and pathological regression. RESULTS: Twenty patients with PM from PDAC (14) and CC (six) underwent 45 PIPAC administrations. Cisplatin-doxorubicin or oxaliplatin were administered to eight and 12 patients, respectively. We experienced one intraoperative complication (small bowel perforation) and 18 grade 1-2 postoperative adverse events according to Common Terminology Criteria for Adverse Events version 4.0. A pathological regression was recorded in 50% of patients (62% in the cisplatin-doxorubicin cohort and 42% in the oxaliplatin one). Median survival from the first PIPAC was 9.7 and 10.9 months for PDAC and CC, respectively. CONCLUSION: PIPAC resulted feasible and safe without relevant toxicity issues, with both cisplatin-doxorubicin and oxaliplatin. The pathological response observed supports the evidence of antitumoral activity. Despite the study limitations, these outcomes are encouraging, recommending PIPAC in prospective, controlled trials in the palliative setting or the first line chemotherapy for PM from PDAC and CC.

3.
In Vivo ; 31(5): 833-840, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28882948

RESUMO

BACKGROUND/AIM: In genetically engineered murine models of pancreatic ductal adenocarcinomas (PDAC), high levels of Runx3 increase the metastatic potential of cancer cells. In this study we evaluated the role of Runx3 in human pancreatic cancer. MATERIALS AND METHODS: Runx3 was retrospectively assessed by immunohistochemistry in seventy-eight tumor samples of patients who underwent surgical resection for PDCA and were followed at least for 24 months. RESULTS: Thirty-two cases resulted completely negative for Runx3; forty-six showed highly variable expression. We established an optimal cut-off value of Runx3 in predicting distant metastasis equal to 0.04. The odds ratio (ORs) for development of distant metastases at multivariate analysis for patients having Runx3 ≥0.04 was 4.26 (p=0.043) and 4.68 (p=0.032) after adjusting for residual tumor and treatment, respectively; OR for development of metastases in multiple sites was 4.28 (p=0.025) for Runx3 ≥0.04. CONCLUSION: Our results support the ability of Runx3 to contribute to the dissemination of human PDAC thus confirming the observations from murine models.


Assuntos
Biomarcadores Tumorais , Subunidade alfa 3 de Fator de Ligação ao Core/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Linhagem Celular Tumoral , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Razão de Chances , Neoplasias Pancreáticas/cirurgia , Prognóstico
4.
Clin Colorectal Cancer ; 10(4): 325-32, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21729677

RESUMO

BACKGROUND: The KRAS mutation is not responsible for all cases of resistance to anti-epidermal growth factor receptors (EGFRs) in metastatic colorectal cancer (mCRC), and new predictive and prognostic factors are actively being sought. PATIENTS AND METHODS: We retrospectively evaluated the efficacy of a cetuximab-containing treatment in 73 patients with mCRC according to KRAS and BRAF mutational status as well as PTEN, c-MET, and insulin-like growth factor receptor (IGF1R) expression. RESULTS: Overall response rate (ORR), median progression-free survival (mPFS), and median overall survival (mOS) were significantly lower in patients with KRAS mutation than in patients with KRAS wild-type; among the population with KRAS wild-type, only 2 patients with BRAF mutations were found and neither of them achieved a response. No significant association was found between PTEN and clinical outcome. Compared with low/normal expression, c-MET overexpression significantly correlated with shorter mPFS and mOS: 3 vs. 5 months (P = .018) and 11 vs. 10 months (P = .037), respectively. In patients with high IGF1R expression, mOS was significantly longer than in those with low/normal expression (14 vs. 8 months; P = .015). CONCLUSION: KRAS mutation significantly correlates with a worse outcome in patients treated with cetuximab, whereas no definitive inference can be drawn about the role of BRAF mutation and PTEN loss of expression. Instead, c-MET overexpression might represent a negative prognostic factor in mCRC and may have a role in resistance to anti-EGFR therapy. Interestingly, IGF1R overexpression seems a favorable prognostic factor in mCRC.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos , Proteínas Proto-Oncogênicas c-met/metabolismo , Receptor IGF Tipo 1/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Cetuximab , Neoplasias Colorretais/mortalidade , DNA de Neoplasias/genética , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Mutação/genética , Metástase Neoplásica , PTEN Fosfo-Hidrolase/genética , Reação em Cadeia da Polimerase , Prognóstico , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras) , Estudos Retrospectivos , Taxa de Sobrevida , Proteínas ras/genética
5.
BMC Gastroenterol ; 11: 32, 2011 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-21453541

RESUMO

BACKGROUND: Two cases of acute hepatitis occurring during treatment with anastrozole have previously been reported, but the underlying mechanisms of liver injury are still uncertain. We report the case of anastrozole-related acute hepatitis with some autoimmune features. CASE PRESENTATION: A 70-year-old woman developed acute hepatitis associated with serum antinuclear antibodies during anastrozole treatment; after drug withdrawal, liver function parameters rapidly improved and serum auto-antibodies were no longer detectable. CONCLUSIONS: Anastrozole-induced hepatotoxicity is a very rare event. Drug-drug interactions or metabolically-mediated damage might be involved, with a possible role of individual susceptibility. Our report suggests that an immune-mediated mechanism may also be considered in anastrozole-related liver injury.


Assuntos
Antineoplásicos Hormonais/efeitos adversos , Inibidores da Aromatase/efeitos adversos , Hepatite Autoimune/diagnóstico , Hepatite Autoimune/etiologia , Nitrilas/efeitos adversos , Triazóis/efeitos adversos , Doença Aguda , Idoso , Anastrozol , Anticorpos Antinucleares/sangue , Antineoplásicos Hormonais/uso terapêutico , Inibidores da Aromatase/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Carcinoma/tratamento farmacológico , Carcinoma/cirurgia , Feminino , Humanos , Nitrilas/uso terapêutico , Resultado do Tratamento , Triazóis/uso terapêutico
6.
Prostate ; 69(7): 744-54, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19152342

RESUMO

BACKGROUND: Prostate carcinomas are androgen-dependent neoplasms which progress toward a hormone-independent phenotype during hormone-deprivation therapy. We evaluated nevirapine, a reverse transcriptase inhibitor, as a new treatment in hormone-refractory prostate carcinoma cells with the aim of restoring the androgen-dependency of tumor cells, the rationale being that endogenous reverse transcriptase is up-regulated in transformed cells and reverse transcriptase inhibitors exert a differentiating activity in human tumors. METHODS AND RESULTS: Nevirapine induced extensive reprogramming of gene expression in vitro with up-regulation of genes that might be silenced during prostate tumor progression (i.e., K18, PSA and androgen receptor) and down-regulation of genes involved in the progression toward an androgen-independent phenotype (i.e., K5, EGFR1, EGF and VEGF-A). Furthermore, nevirapine down-regulated the growth of prostate carcinoma xenografts in athymic mice and induced a differentiated phenotype in vivo with increased K18 expression. Interestingly, the drug restored androgen signaling by enhancing the ability of tumor cells to respond to dihydrotestosterone stimulation and to the antiproliferative activity of the androgen receptor blocker bicalutamide. Finally, nevirapine pretreatment increased the susceptibility of tumor cells to docetaxel, by enhancing their ability to undergo apoptosis. CONCLUSIONS: These data suggest that nevirapine may be clinically tested in human hormone-refractory prostate carcinoma to restore the susceptibility to androgen deprivation therapy or to docetaxel.


Assuntos
Neoplasias Hormônio-Dependentes/tratamento farmacológico , Neoplasias Hormônio-Dependentes/metabolismo , Nevirapina/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Inibidores da Transcriptase Reversa/farmacologia , Antagonistas de Androgênios/farmacologia , Antagonistas de Receptores de Andrógenos , Anilidas/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Di-Hidrotestosterona/farmacologia , Docetaxel , Sinergismo Farmacológico , Humanos , Masculino , Camundongos , Camundongos Nus , Neoplasias Hormônio-Dependentes/patologia , Nitrilas/farmacologia , Neoplasias da Próstata/patologia , RNA Neoplásico/química , RNA Neoplásico/genética , Distribuição Aleatória , Receptores Androgênicos/genética , Transdução de Sinais/efeitos dos fármacos , Taxoides/farmacologia , Compostos de Tosil/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Biochem Biophys Res Commun ; 349(1): 192-9, 2006 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-16930531

RESUMO

Fibroblast growth factor (FGF)1 is released from cells as a constituent of a complex that contains the small calcium binding protein S100A13, and the p40 kDa form of synaptotagmin (Syt)1, through an ER-Golgi-independent stress-induced pathway. FGF1 and the other components of its secretory complex are signal peptide-less proteins. We examined their capability to interact with lipid bilayers by studying protein-induced carboxyfluorescein release from liposomes of different phospholipid (pL) compositions. FGF1, p40 Syt1, and S100A13 induced destabilization of liposomes composed of acidic but not of zwitterionic pL. We produced mutants of FGF1 and p40 Syt1, in which specific basic amino acid residues in the regions that bind acidic pL were substituted. The ability of these mutants to induce liposomes destabilization was strongly attenuated, and they exhibited drastically diminished spontaneous and stress-induced release. Apparently, the non-classical release of FGF1 and p40 Syt1 involves destabilization of membranes containing acidic pL.


Assuntos
Fator 1 de Crescimento de Fibroblastos/química , Sinaptotagmina I/química , Animais , Membrana Celular/metabolismo , Complexo de Golgi/metabolismo , Bicamadas Lipídicas/química , Lipossomos/química , Camundongos , Modelos Biológicos , Células NIH 3T3 , Proteínas Recombinantes/química
8.
J Clin Endocrinol Metab ; 90(10): 5663-71, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16030158

RESUMO

CONTEXT: Two classes of repeated genomic elements, retrotransposons and endogenous retroviruses, encode for endogenous nontelomeric reverse transcriptase (RT), a gene that is down-regulated in differentiated cells but is highly expressed in embryonic and transformed tissues. Two nonnucleosidic RT inhibitors, efavirenz and nevirapine, currently used in HIV treatment, reversibly down-regulate tumor growth and induce differentiation in several human tumor cell models. OBJECTIVES: Aggressive biological behavior and loss of specific thyroid cell functions, such as thyroglobulin, thyroid peroxidase, TSH receptor, Na/I symporter expression, and iodine uptake are features of anaplastic thyroid cancer. Thus, we evaluated the use of RT inhibitors as a potentially differentiating and molecular-targeted treatment of this neoplasm. RESULTS: Our findings showed that nevirapine and efavirenz reversibly inhibit cell proliferation without triggering cell death in the undifferentiated thyroid carcinoma ARO and FRO cells, which exhibited high levels of endogenous RT activity. Inhibition of cell growth was correlated with accumulation of cells in the G0/G1 phase of the cell cycle, with a concomitant decrease in the S phase. Moreover, treated cells demonstrated a differentiated phenotype and a significant reprogramming of gene expression characterized by up-regulation of the TSH receptor, thyroglobulin, thyroid peroxidase, and Na/I symporter genes. Interestingly, RT inhibition reestablished the ability to uptake iodine in response to TSH either in vitro or in vivo and reversibly down-regulated tumor growth in mice xenografts of ARO cells. CONCLUSIONS: These findings support the need for clinical trials to clarify whether RT inhibitors may restore the sensitivity to radiometabolic therapy in anaplastic thyroid tumors.


Assuntos
Carcinoma/metabolismo , Carcinoma/fisiopatologia , Proliferação de Células/efeitos dos fármacos , Iodo/metabolismo , Inibidores da Transcriptase Reversa/farmacologia , Transdução de Sinais/efeitos dos fármacos , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/fisiopatologia , Tireotropina/fisiologia , Animais , Apoptose/efeitos dos fármacos , Carcinoma/enzimologia , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Immunoblotting , Camundongos , Camundongos Nus , Necrose , Transplante de Neoplasias , DNA Polimerase Dirigida por RNA/metabolismo , Receptores da Tireotropina/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias da Glândula Tireoide/enzimologia , Transplante Heterólogo
9.
J Cell Sci ; 116(Pt 24): 4871-81, 2003 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-14625381

RESUMO

Non-classical protein release independent of the ER-Golgi pathway has been reported for an increasing number of proteins lacking an N-terminal signal sequence. The export of FGF1 and IL-1alpha, two pro-angiogenic polypeptides, provides two such examples. In both cases, export is based on the Cu2+-dependent formation of multiprotein complexes containing the S100A13 protein and might involve translocation of the protein across the membrane as a 'molten globule'. FGF1 and IL-1alpha are involved in pathological processes such as restenosis and tumor formation. Inhibition of their export by Cu2+ chelators is thus an effective strategy for treatment of several diseases.


Assuntos
Retículo Endoplasmático/metabolismo , Fator 1 de Crescimento de Fibroblastos/metabolismo , Interleucina-1/metabolismo , Sinais Direcionadores de Proteínas/fisiologia , Animais , Hipóxia Celular/fisiologia , Membrana Celular/metabolismo , Cobre/metabolismo , Humanos , Fluidez de Membrana/fisiologia , Modelos Estruturais , Neovascularização Patológica/metabolismo , Transporte Proteico , Proteínas S100
11.
Proc Natl Acad Sci U S A ; 100(11): 6700-5, 2003 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-12754378

RESUMO

The induction of an acute inflammatory response followed by the release of polypeptide cytokines and growth factors from peripheral blood monocytes has been implicated in mediating the response to vascular injury. Because the Cu2+-binding proteins IL-1alpha and fibroblast growth factor 1 are exported into the extracellular compartment in a stress-dependent manner by using intracellular Cu2+ to facilitate the formation of S100A13 heterotetrameric complexes and these signal peptideless polypeptides have been implicated as regulators of vascular injury in vivo, we examined the ability of Cu2+ chelation to repress neointimal thickening in response to injury. We observed that the oral administration of the Cu2+ chelator tetrathiomolybdate was able to reduce neointimal thickening after balloon injury in the rat. Interestingly, although immunohistochemical analysis of control neointimal sections exhibited prominent staining for MAC1, IL-1alpha, S100A13, and the acidic phospholipid phosphatidylserine, similar sections obtained from tetrathiomolybdate-treated animals did not. Further, adenoviral gene transfer of the IL-1 receptor antagonist during vascular injury also significantly reduced the area of neointimal thickening. Our data suggest that intracellular copper may be involved in mediating the response to injury in vivo by its ability to regulate the stress-induced release of IL-1alpha by using the nonclassical export mechanism employed by human peripheral blood mononuclear cells in vitro.


Assuntos
Vasos Sanguíneos/efeitos dos fármacos , Quelantes/farmacologia , Cobre/química , Molibdênio/farmacologia , Adenoviridae/genética , Animais , Vasos Sanguíneos/lesões , Vasos Sanguíneos/metabolismo , Ceruloplasmina/metabolismo , Quelantes/química , Humanos , Imuno-Histoquímica , Masculino , Molibdênio/química , Ratos , Ratos Sprague-Dawley , Transfecção
12.
J Cell Sci ; 116(Pt 13): 2687-96, 2003 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12746488

RESUMO

Copper is involved in the promotion of angiogenic and inflammatory events in vivo and, although recent clinical data has demonstrated the potential of Cu2+ chelators for the treatment of cancer in man, the mechanism for this activity remains unknown. We have previously demonstrated that the signal peptide-less angiogenic polypeptide, FGF1, uses intracellular Cu2+ to facilitate the formation of a multiprotein aggregate that enables the release of FGF1 in response to stress and that the expression of the precursor form but not the mature form of IL-1alpha represses the stress-induced export of FGF1 from NIH 3T3 cells. We report here that IL-1alpha is a Cu2+-binding protein and human U937 cells, like NIH 3T3 cells, release IL-1alpha in response to temperature stress in a Cu2+-dependent manner. We also report that the stress-induced export of IL-1alpha involves the intracellular association with the Cu2+-binding protein, S100A13. In addition, the expression of a S100A13 mutant lacking a sequence novel to this gene product functions as a dominant-negative repressor of IL-1alpha release, whereas the expression of wild-type S100A13 functions to eliminate the requirement for stress-induced transcription. Lastly, we present biophysical evidence that IL-1alpha may be endowed with molten globule character, which may facilitate its release through the plasma membrane. Because Cu2+ chelation also represses the release of FGF1, the ability of Cu2+ chelators to potentially serve as effective clinical anti-cancer agents may be related to their ability to limit the export of these proinflammatory and angiogenic signal peptide-less polypeptides into the extracellular compartment.


Assuntos
Cobre/metabolismo , Interleucina-1/metabolismo , Neovascularização Patológica/metabolismo , Proteínas S100/fisiologia , Estresse Fisiológico/metabolismo , Animais , Antineoplásicos/farmacologia , Quelantes/farmacologia , Cobre/farmacologia , Citosol/metabolismo , Líquido Extracelular/metabolismo , Fator 1 de Crescimento de Fibroblastos/metabolismo , Humanos , Camundongos , Mutação/genética , Células NIH 3T3 , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/fisiopatologia , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Proteínas S100/deficiência , Proteínas S100/genética , Estresse Fisiológico/fisiopatologia , Temperatura , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/genética , Células U937
13.
J Biol Chem ; 278(18): 16405-13, 2003 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-12598523

RESUMO

Aberrant activations of the Notch and fibroblast growth factor receptor (FGFR) signaling pathways have been correlated with neoplastic growth in humans and other mammals. Here we report that the suppression of Notch signaling in NIH 3T3 cells by the expression of either the extracellular domain of the Notch ligand Jagged1 or dominant-negative forms of Notch1 and Notch2 results in the appearance of an exaggerated fibroblast growth factor (FGF)-dependent transformed phenotype characterized by anchorage-independent growth in soft agar. Anchorage-independent growth exhibited by Notch-repressed NIH 3T3 cells may result from prolonged FGFR stimulation caused by both an increase in the expression of prototypic and oncogenic FGF gene family members and the nonclassical export of FGF1 into the extracellular compartment. Interestingly, FGF exerts a negative effect on Notch by suppressing CSL (CBF-1/RBP-Jk/KBF2 in mammals, Su(H) in Drosophila and Xenopus, and Lag-2 in Caenorhabditis elegans)-dependent transcription, and the ectopic expression of constitutively active forms of Notch1 or Notch2 abrogates FGF1 release and the phenotypic effects of FGFR stimulation. These data suggest that communication between the Notch and FGFR pathways may represent an important reciprocal autoregulatory mechanism for the regulation of normal cell growth.


Assuntos
Transformação Celular Neoplásica , Fator 1 de Crescimento de Fibroblastos/fisiologia , Proteínas de Membrana/fisiologia , Proteínas , Células 3T3 , Animais , Proteínas de Ligação ao Cálcio , Divisão Celular , Proteínas de Drosophila , Fator 1 de Crescimento de Fibroblastos/genética , Fibroblastos/citologia , Peptídeos e Proteínas de Sinalização Intercelular , Proteína Jagged-1 , Glicoproteínas de Membrana/fisiologia , Camundongos , Biossíntese de Proteínas , RNA Mensageiro/metabolismo , Receptores de Superfície Celular/fisiologia , Receptores de Fatores de Crescimento de Fibroblastos/fisiologia , Receptores Notch , Proteínas Serrate-Jagged , Proteínas de Xenopus
14.
Anticancer Res ; 22(4): 2179-84, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12174901

RESUMO

BACKGROUND: VEGF is a growth factor involved in the regulation of angiogenesis, a process that plays a central role in tumor growth. It has been suggested that mutations of p53 and activation of the Ras/MAPK pathway may contribute to the up-regulation of VEGF expression and induction of angiogenesis. PATIENTS AND METHODS: We explored the expression of p53 and VEGF and p44MAPK phosphorylation in 43 human colorectal carcinomas, as well as in peritumoral mucosas, and in normal mucosas in order to establish a correlation between VEGF expression and either mutations of p53 or phosphorylation of p44MAPK. Overexpression of p53 in tumor tissues was interpreted as evidence of mutations. RESULTS: p53 was overexpressed in 22 out of 43 tumors; MAPK was phosphorylated in 25 out of 43 cases whereas only 4 out of 22 peritumoral mucosas showed a moderate phosphorylation of p44MAPK VEGF was up-regulated in 22 out of 43 tumors, moderately expressed in 4 out of 22 peritumoral mucosas and not detectable in normal mucosa. Immunohistochemical analysis showed the presence of a phosphorylated form of p44 MAPK only in neoplastic cells. Statistical analysis demonstrated a significant correlation between p53 and VEGF expression (p<0.03) as well as between VEGF expression and p44 MAPK phosphorylation (p<0.002). CONCLUSION: These data suggest that mutations of p53 and activation of the Ras/MAPK pathway may play a role in the induction of VEGF expression in human colorectal cancer.


Assuntos
Adenocarcinoma/patologia , Neoplasias do Colo/patologia , Neoplasias Colorretais/patologia , Fatores de Crescimento Endotelial/análise , Linfocinas/análise , Proteínas Quinases Ativadas por Mitógeno/análise , Neoplasias Retais/patologia , Proteína Supressora de Tumor p53/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Células Tumorais Cultivadas , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
15.
J Cell Biol ; 158(2): 201-8, 2002 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-12135982

RESUMO

The release of signal peptideless proteins occurs through nonclassical export pathways and the release of fibroblast growth factor (FGF)1 in response to cellular stress is well documented. Although biochemical evidence suggests that the formation of a multiprotein complex containing S100A13 and Synaptotagmin (Syt)1 is important for the release of FGF1, it is unclear where this intracellular complex is assembled. As a result, we employed real-time analysis using confocal fluorescence microscopy to study the spatio-temporal aspects of this nonclassical export pathway and demonstrate that heat shock stimulates the redistribution of FGF1 from a diffuse cytosolic pattern to a locale near the inner surface of the plasma membrane where it colocalized with S100A13 and Syt1. In addition, coexpression of dominant-negative mutant forms of S100A13 and Syt1, which both repress the release of FGF1, failed to inhibit the stress-induced peripheral redistribution of intracellular FGF1. However, amlexanox, a compound that is known to attenuate actin stress fiber formation and FGF1 release, was able to repress this process. These data suggest that the assembly of the intracellular complex involved in the release of FGF1 occurs near the inner surface of the plasma membrane and is dependent on the F-actin cytoskeleton.


Assuntos
Proteínas de Ligação ao Cálcio , Fator 1 de Crescimento de Fibroblastos , Células 3T3 , Animais , Fator 1 de Crescimento de Fibroblastos/química , Fator 1 de Crescimento de Fibroblastos/metabolismo , Membranas Intracelulares/metabolismo , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/metabolismo , Camundongos , Microscopia Confocal , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/metabolismo , Ligação Proteica , Transporte Proteico , Proteínas S100/química , Proteínas S100/metabolismo , Sinaptotagmina I , Sinaptotagminas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...