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1.
J Endocrinol Invest ; 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37962809

RESUMO

BACKGROUND AND AIMS: The role of overweight and obesity in the development of atrial fibrillation (AF) is well established; however, the differential effect on the occurrence and recurrence of AF remains uncertain. The aim of this review is to compare the effect of underweight and varying degrees of obesity on onset of AF and in recurrent post-ablation AF, and, when possible, in relation to sex. METHODS: A systematic literature search was conducted in PubMed, Embase, and Cochrane Library from inception to January 31, 2023. Studies reporting frequency of newly-diagnosed AF and of recurrent post-ablation AF in different BMI categories, were included. 3400 records were screened and 50 met the inclusion criteria. Standardized data search and abstraction were performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) Statement. Data were extracted from the manuscripts and were analyzed using a random effect model. The outcome was the occurrence of AF in population studies and in patients undergoing ablation. RESULTS: Data from 50 studies were collected, of which 27 for newly-diagnosed AF and 23 for recurrent post-ablation AF, for a total of 15,134,939 patients, of which 15,115,181 in studies on newly-diagnosed AF and 19,758 in studies on recurrent post-ablation AF. Compared to normal weight, the increase in AF was significant (p < 0.01) for overweight, obese, and morbidly obese patients for newly-diagnosed AF, and for obese and morbidly obese patients for recurrent post-ablation AF. Newly-diagnosed AF was more frequent in obese female than obese male patients. CONCLUSION: The effect of increased BMI was greater on the onset of AF, and obese women were more affected than men.

2.
Cytokine Growth Factor Rev ; 44: 1-10, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30393044

RESUMO

The eighth annual conference of "Innovative therapy, monoclonal antibodies, and beyond" was held in Milan on Jan. 26, 2018, and hosted by Fondazione IRCCS-Istituto Nazionale dei Tumori (Fondazione IRCCS INT). The conference was divided into two main scientific sessions, of i) pre-clinical assays and novel biotargets, and ii) clinical translation, as well as a third session of presentations from young investigators, which focused on recent achievements within Fondazione IRCCS INT on immunotherapy and targeted therapies. Presentations in the first session addressed the issue of cancer immunotherapy activity with respect to tumor heterogeneity, with key topics addressing: 1) tumor heterogeneity and targeted therapy, with the definition of the evolutionary Index as an indicator of tumor heterogeneity in both space and time; 2) the analysis of cancer evolution, with the introduction of the TRACERx Consortium-a multi-million pound UK research project focused on non-small cell lung cancer (NSCLC); 3) the use of anti-estrogen agents to boost immune recognition of breast cancer cells; and 4) the high degree of functional plasticity within the NK cell repertoire, including the expansion of adaptive NK cells following viral challenges. The second session addressed: 1) the effectiveness of radiotherapy to enhance the proportion of patients responsive to immune-checkpoint blockers (ICBs); 2) the use of MDSC scores in selecting melanoma patients with high probability to be responsive to ICBs; and 3) the relevance of the gut microbiome as a predictive factor, and the potential of its perturbation in increasing the immune response rate to ICBs. Overall, a picture emerged of tumor heterogeneity as the main limitation that impairs the effectiveness of anti-cancer therapies. Thus, the choice of a specific therapy based on reproducible and selective predictive biomarkers is an urgent unmet clinical need that should be addressed in order to increase the proportion of long-term responding patients and to improve the sustainability of novel drugs.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Imunoterapia , Neoplasias/terapia , Animais , Microbioma Gastrointestinal , Humanos , Neoplasias/imunologia , Neoplasias/microbiologia
4.
Oncogene ; 36(12): 1721-1732, 2017 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-27641338

RESUMO

We have previously shown that the d16HER2 splice variant is linked to HER2-positive breast cancer (BC) tumorigenesis, progression and response to Trastuzumab. However, the mechanisms by which d16HER2 contributes to HER2-driven aggressiveness and targeted therapy susceptibility remain uncertain. Here, we report that the d16HER2-positive mammary tumor cell lines MI6 and MI7, derived from spontaneous lesions of d16HER2 transgenic (tg) mice and resembling the aggressive features of primary lesions, are enriched in the expression of Wnt, Notch and epithelial-mesenchymal transition pathways related genes compared with full-length wild-type (WT) HER2-positive cells (WTHER2_1 and WTHER2_2) derived from spontaneous tumors arising in WTHER2 tg mice. MI6 cells exhibited increased resistance to anoikis and significantly higher mammosphere-forming efficiency (MFE) and self-renewal capability than the WTHER2-positive counterpart. Furthermore, d16HER2-positive tumor cells expressed a higher fraction of CD29High/CD24+/SCA1Low cells and displayed greater in vivo tumor engraftment in serial dilution conditions than WTHER2_1 cells. Accordingly, NOTCH inhibitors impaired mammosphere formation only in MI6 cells. A comparative analysis of stemness-related features driven by d16HER2 and WTHER2 in ad hoc engineered human BC cells (MCF7 and T47D) revealed a higher MFE and aldehyde dehydrogenase-positive staining in d16HER2- vs WTHER2-infected cells, sustaining consistent BC-initiating cell enrichment in the human setting. Moreover, marked CD44 expression was found in MCF7_d16 and T47D_d16 cells vs their WTHER2 and Mock counterparts. Clinically, BC cases from two distinct HER2-positive cohorts characterized by high levels of expression of the activated-d16HER2 metagene were significantly enriched in the Notch family and signal transducer genes vs those with low levels of the metagene.


Assuntos
Processamento Alternativo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Células-Tronco Neoplásicas/metabolismo , Receptor ErbB-2/genética , Animais , Apoptose/genética , Biomarcadores , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Análise por Conglomerados , Progressão da Doença , Transição Epitelial-Mesenquimal/genética , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Camundongos , Mutação , Receptor ErbB-2/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais
5.
Br J Cancer ; 113(2): 354-63, 2015 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-26103569

RESUMO

BACKGROUND: The melanocortin-1-receptor (MC1R) gene regulates human pigmentation and is highly polymorphic in populations of European origins. The aims of this study were to evaluate the association between MC1R variants and the risk of non-melanoma skin cancer (NMSC), and to investigate whether risk estimates differed by phenotypic characteristics. METHODS: Data on 3527 NMSC cases and 9391 controls were gathered through the M-SKIP Project, an international pooled-analysis on MC1R, skin cancer and phenotypic characteristics. We calculated summary odds ratios (SOR) with random-effect models, and performed stratified analyses. RESULTS: Subjects carrying at least one MC1R variant had an increased risk of NMSC overall, basal cell carcinoma (BCC) and squamous cell carcinoma (SCC): SOR (95%CI) were 1.48 (1.24-1.76), 1.39 (1.15-1.69) and 1.61 (1.35-1.91), respectively. All of the investigated variants showed positive associations with NMSC, with consistent significant results obtained for V60L, D84E, V92M, R151C, R160W, R163Q and D294H: SOR (95%CI) ranged from 1.42 (1.19-1.70) for V60L to 2.66 (1.06-6.65) for D84E variant. In stratified analysis, there was no consistent pattern of association between MC1R and NMSC by skin type, but we consistently observed higher SORs for subjects without red hair. CONCLUSIONS: Our pooled-analysis highlighted a role of MC1R variants in NMSC development and suggested an effect modification by red hair colour phenotype.


Assuntos
Predisposição Genética para Doença , Receptor Tipo 1 de Melanocortina/genética , Neoplasias Cutâneas/genética , Carcinoma Basocelular/genética , Carcinoma de Células Escamosas/genética , Cor de Cabelo , Humanos , Razão de Chances , Fenótipo , Risco , Neoplasias Cutâneas/etiologia
7.
Breast Cancer Res Treat ; 141(1): 101-10, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23942848

RESUMO

Clinical trials have shown the efficacy of trastuzumab-based adjuvant therapy in HER2-positive breast cancers, but routine clinical use awaits evaluation of compliance, safety, and effectiveness. Adjuvant trastuzumab-based therapy in routine clinical use was evaluated in the retrospective study GHEA, recording 1,002 patients treated according to the HERA protocol between March 2005 and December 2009 in 42 Italian oncology departments; 874 (87.23 %) patients completed 1-year trastuzumab treatment. In 128 patients (12.77 %), trastuzumab was withdrawn due to cardiac or non-cardiac toxicity (28 and 29 patients, respectively), disease progression (5 patients) or the clinician's decision (66 patients). In addition, 156 patients experienced minor non-cardiac toxicities; 10 and 44 patients showed CHF and decreased LVEF, respectively, at the end of treatment. Compliance and safety of adjuvant trastuzumab-based therapy in Italian hospitals were high and close to those reported in the HERA trial. With a median follow-up of 32 months, 107 breast cancer relapses were recorded (overall frequency, 10.67 %), and lymph node involvement, estrogen receptor negativity, lymphoid infiltration, and vascular invasion were identified as independent prognostic factors for tumor recurrence, indicating that relapses were associated with advanced tumor stage. Analysis of site and frequency of distant metastases showed that bone metastases were significantly more frequent during or immediately after trastuzumab (<18 months from the start of treatment) compared to recurrences in bone after the end of treatment and wash-out of the drug (>18 months from the start of treatment) (35.89 vs. 14.28 %, p = 0.0240); no significant differences were observed in recurrences in the other recorded body sites, raising the possibility that the protection exerted by trastuzumab is lower in bone metastases.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Carcinoma/tratamento farmacológico , Quimioterapia Adjuvante , Adulto , Anticorpos Monoclonais Humanizados/efeitos adversos , Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais , Neoplasias da Mama/química , Neoplasias da Mama/patologia , Carcinoma/química , Carcinoma/secundário , Terapia Combinada , Intervalo Livre de Doença , Feminino , Seguimentos , Genes erbB-2 , Cardiopatias/tratamento farmacológico , Humanos , Itália , Adesão à Medicação , Pessoa de Meia-Idade , Terapia Neoadjuvante , Invasividade Neoplásica , Metástase Neoplásica , Proteínas de Neoplasias/análise , Estadiamento de Neoplasias , Prognóstico , Receptor ErbB-2/análise , Estudos Retrospectivos , Fatores de Risco , Trastuzumab
8.
Ann Oncol ; 22(8): 1886-93, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21343382

RESUMO

BACKGROUND: Mounting evidence suggests that recurrence of resected head and neck squamous cell carcinomas (HNSCCs) is due to the outgrowth of unrecognized residual tumor cells as well as to the premalignant and/or precursor-field epithelial cells. We studied the impact of processes triggered by HNSCC surgery in stimulating both residual tumor cells [demonstrated to overexpress epidermal growth factor receptor (EGFR)], and premalignant cells surrounding the resected lesion. PATIENTS AND METHODS: EGFR expression/activation by immunohistochemistry/biochemistry and gene status by FISH were investigated in 23 primary HNSCCs and surrounding tissues. The ability to induce cell proliferation of wound healing drainages collected from 12 relapsed and 11 not relapsed patients was evaluated by a colorimetric assay in squamous cell carcinoma cell lines A431 (carrying EGFR amplification) and CAL27 (carrying three EGFR copies) in the presence/absence of EGFR therapeutic inhibitors. RESULTS: Primary tumors showed intermediate/high EGFR expression (91%), EGFR phosphorylation and EGFR-positive FISH (35%). Normal, metaplastic and dysplastic epithelium surrounding the resected tumor displayed EGFR overexpression. EGFR activation and gene amplification were observed in normal and dysplastic epithelium, respectively. Each tested wound healing drainage induced the cells to proliferate and the proliferation was significantly higher in relapsed compared with not relapsed HNSCC patients (P = 0.02 and P = 0.03). Anti-EGFR treatments inhibited the drainage-induced proliferation, with the highest inhibitory efficiency by cetuximab on A431 cells, while CAL27 cell growth was more efficiently inhibited by tyrosine kinase inhibitors. CONCLUSIONS: Surgery could favor the proliferation of cells showing EGFR overexpression/activation/amplification such as residual tumor cells and/or precursor-field epithelial cells already present after surgery. Treatment with anti-EGFR reagents inhibits wound-induced stimulation, according to the EGFR family status.


Assuntos
Carcinoma de Células Escamosas/patologia , Receptores ErbB/biossíntese , Neoplasias de Cabeça e Pescoço/patologia , Recidiva Local de Neoplasia/patologia , Cicatrização , Adulto , Idoso , Líquidos Corporais/metabolismo , Carcinoma de Células Escamosas/cirurgia , Linhagem Celular Tumoral , Proliferação de Células , Células Epiteliais/patologia , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/sangue , Feminino , Expressão Gênica , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Estadiamento de Neoplasias , Proteínas Oncogênicas v-erbB/metabolismo , Receptor ErbB-2/metabolismo
9.
Ann Oncol ; 19(10): 1706-12, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18544559

RESUMO

BACKGROUND: The standardization of the HER2 score and recent changes in therapeutic modalities points to the need for a reevaluation of the role of HER2 in recently diagnosed breast carcinoma. PATIENTS AND METHODS: A multicenter, retrospective study of 1794 primary breast carcinomas diagnosed in Italy in 2000/2001 and scored in HER2 four categories according to immunohistochemistry was conducted. RESULTS: Ductal histotype, vascular invasion, grade, MIB1 positivity, estrogen and progesterone receptor expression differed significantly in HER2 3+ tumors compared with the other categories. HER2 2+ tumors almost showed values intermediate between those of the negative and the 3+ subgroups. The characteristics of HER2 1+ tumors were found to be in between those of HER2 0 and 2+ tumors. With a median follow-up of 54 months, HER2 3+ status was associated with higher relapse rates in node-positive and node-negative subgroups, while HER2 2+ only in node positive. Analysis of relapses according to type of therapy provided evidence of responsiveness of HER2-positive tumors to chemotherapy, especially taxanes. CONCLUSIONS: The present prognostic significance of HER2 is correlated to receptor expression level and points to the need to consider HER2 2+ and HER2 3+ tumors as distinct diseases with different outcomes and specific features.


Assuntos
Neoplasias da Mama/enzimologia , Neoplasias da Mama/terapia , Receptor ErbB-2/biossíntese , Antineoplásicos Hormonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/patologia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Mastectomia , Pessoa de Meia-Idade , Estudos Retrospectivos
10.
J Pathol ; 214(3): 357-67, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18044827

RESUMO

Prediction of the clinical outcome of breast cancer is multi-faceted and challenging. There is growing evidence that the complexity of the tumour micro-environment, consisting of several cell types and a complex mixture of proteins, plays an important role in development, progression, and response to therapy. In the current study, we investigated whether invasive breast tumours can be classified on the basis of the expression of extracellular matrix (ECM) components and whether such classification is representative of different clinical outcomes. We first examined the matrix composition of 28 primary breast carcinomas by morphology and gene expression profiling using 22K oligonucleotide Agilent microarrays. Hierarchical clustering of the gene expression profile of 278 ECM-related genes derived from the literature divided the tumours into four main groups (ECM1-4). A set of selected differentially expressed genes was validated by immunohistochemistry. The robustness of the ECM classification was confirmed by studying the four ECM groups in a previously published gene expression data set of 114 early-stage primary breast carcinomas profiled using cDNA arrays. Univariate survival analysis showed significant differences in clinical outcome among the various ECM subclasses. One set of tumours, designated ECM4, had a favourable outcome and was defined by the overexpression of a set of protease inhibitors belonging to the serpin family, while tumours with an ECM1 signature had a poorer prognosis and showed high expression of integrins and metallopeptidases, and low expression of several laminin chains. Furthermore, we identified three surrogate markers of ECM1 tumours: MARCO, PUNC, and SPARC, whose expression levels were associated with breast cancer survival and risk of recurrence. Our findings suggest that primary breast tumours can be classified based upon ECM composition and that this classification provides relevant information on the biology of breast carcinomas, further supporting the hypothesis that clinical outcome is strongly related to stromal characteristics.


Assuntos
Neoplasias da Mama/classificação , Proteínas da Matriz Extracelular/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos , Biomarcadores Tumorais , Neoplasias da Mama/genética , Moléculas de Adesão Celular Neuronais/genética , Feminino , Humanos , Imunoglobulinas/genética , Imuno-Histoquímica , Osteonectina/genética , Prognóstico , Receptores Imunológicos/genética , Análise de Sobrevida
11.
J Neurol Sci ; 253(1-2): 88-9, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17217966

RESUMO

Sjogren's syndrome (SS) is a systemic autoimmune disorder, and neurological involvement may frequently occur. Here we describe a 79-year-old woman who came to our attention for a sudden right incomplete 3rd cranial nerve palsy. Following extensive investigations, a diagnosis of primary SS was reached, and the patient recovered after treatment with ev Ig and steroids. Therefore, we suggest that SS should be considered in apparently idiopathic 3rd cranial nerve palsies, since, with the appropriate treatment, they might be transient and reversible.


Assuntos
Doenças do Nervo Oculomotor/diagnóstico , Doenças do Nervo Oculomotor/etiologia , Síndrome de Sjogren/complicações , Síndrome de Sjogren/diagnóstico , Idoso , Diplopia/diagnóstico , Diplopia/etiologia , Diagnóstico Precoce , Feminino , Humanos
13.
Neurol Sci ; 28(6): 339-41, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18175083

RESUMO

Here we report the case of a 73-year-old Italian woman affected by genetically confirmed oculopharyngeal muscular dystrophy (OPMD) with a negative family history. As OPMD is usually transmitted as an autosomal-dominant meiotically stable trait, this case allows us to suggest that putative de novo OPMD mutations might occur more frequently than previously thought; moreover, when compatible with a proper clinical phenotype, OPMD might be included in the differential diagnosis even in the absence of a positive family history.


Assuntos
Distrofia Muscular Oculofaríngea/diagnóstico , Distrofia Muscular Oculofaríngea/fisiopatologia , Idoso , Análise Mutacional de DNA/métodos , Feminino , Humanos , Itália , Músculo Esquelético/patologia , Distrofia Muscular Oculofaríngea/genética , Proteína II de Ligação a Poli(A)/genética
14.
Neurol Sci ; 27(4): 278-80, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16998733

RESUMO

Chickenpox may lead to several different neurological complications, but optic neuritis has rarely been described; in particular, only one case of isolated bilateral anterior optic neuritis (AON) in an immune-competent adult has so far been reported. We describe a second case of this type and consider similarities and differences between our patient and all other cases of AON following chickenpox. Then, we discuss the therapeutic role of steroids and advance the hypothesis of different pathogenetic pathways in immune-competent and immune-compromised subjects.


Assuntos
Varicela/complicações , Imunocompetência/fisiologia , Neurite Óptica/etiologia , Adulto , Feminino , Angiofluoresceinografia/métodos , Herpesvirus Humano 3/imunologia , Herpesvirus Humano 3/isolamento & purificação , Humanos , Neurite Óptica/patologia , Neurite Óptica/fisiopatologia
15.
Neurol Sci ; 27(1): 24-32, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16688596

RESUMO

Extracorporeal photochemotherapy (ECP) is an immunomodulating procedure consisting of autologous reinfusion of peripheral blood mononuclear cells (PBMC) after direct exposure to 8-methoxy-psoralen and UV-A. It has been described as a successful treatment for different T-cell-mediated diseases and preliminary results suggest that ECP might be effective in the treatment of relapsing-remitting multiple sclerosis, but does not significantly alter the course of the progressive form of MS. In this study, we report the safety data and some preliminary efficacy evidence obtained using ECP in the treatment of five patients with refractory relapsing-remitting (RR) MS: in most cases ECP induced a reduction in the relapse rate and an EDSS stabilisation, with an apparent general MRI stabilisation. In conclusion, our results confirm ECP safety and tolerability and suggest that this treatment might be useful as a therapeutic alternative in the subgroup of RRMS patients not responsive to or not eligible for traditional immunomodulating or immunosuppressive treatments.


Assuntos
Terapia de Imunossupressão/métodos , Esclerose Múltipla Recidivante-Remitente/terapia , Fotoferese/métodos , Adulto , Feminino , Humanos , Terapia de Imunossupressão/efeitos adversos , Terapia de Imunossupressão/estatística & dados numéricos , Contagem de Linfócitos , Imageamento por Ressonância Magnética , Masculino , Esclerose Múltipla Recidivante-Remitente/diagnóstico , Esclerose Múltipla Recidivante-Remitente/imunologia , Fotoferese/efeitos adversos , Fotoferese/estatística & dados numéricos , Projetos Piloto , Prevenção Secundária , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/efeitos da radiação , Tempo , Resultado do Tratamento
17.
Endocr Relat Cancer ; 13(1): 221-32, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16601290

RESUMO

A splice variant of the human gene HER2, lacking exon-16 (DeltaHER2) which encodes a small extracellular region, has been described. This altered receptor forms disulfide bond-stabilized homodimers. We report here that the DeltaHER2 splice variant represents about 9% of the HER2 mRNA obtained from most of the 46 breast carcinoma samples with HER2 expression levels ranging from 3+ to 0 by HercepTest. Analysis of human cells transfected with DeltaHER2 or wild-type (WT) cDNA revealed no growth of WT cells in nude mice, whereas clones expressing 10-fold less DeltaHER2 were tumorigenic. Unlike WT transfectants, DeltaHER2-expressing cells showed low sensitivity to two new therapeutic drugs targeting receptors of the HER family (ZD1839 and Trastuzumab), whereas an inhibitor of the HER2 tyrosine kinase domain (Emodin) blocked activation of both DeltaHER2 and WT transfectants. Taken together, our findings indicate that the DeltaHER2 transcript encodes the transforming form of the oncoprotein. It is plausible that malignant transformation arises when a critical threshold of DeltaHER2 is reached in HER2-overexpressing tumors. Specific inhibitors of HER2 catalytic activity represent a promising approach to therapy of HER2-overexpressing tumors.


Assuntos
Neoplasias da Mama/genética , Éxons/genética , Splicing de RNA , Receptor ErbB-2/genética , Células 3T3 , Animais , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Antineoplásicos/uso terapêutico , Apoptose , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Proliferação de Células , Células Cultivadas , Tolerância a Medicamentos , Emodina/farmacologia , Inibidores Enzimáticos/farmacologia , Receptores ErbB/antagonistas & inibidores , Citometria de Fluxo , Gefitinibe , Regulação Neoplásica da Expressão Gênica , Humanos , Rim/efeitos dos fármacos , Rim/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Reação em Cadeia da Polimerase , Quinazolinas/uso terapêutico , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/metabolismo , Trastuzumab
18.
Endocr Relat Cancer ; 12(2): 393-406, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15947111

RESUMO

The association between expression of the 67 kDa laminin receptor (67LR) and tumor aggressiveness has been convincingly demonstrated although the exact function of this molecule in the metastatic process has remained unclear. In this study, we tested whether the laminin-1, upon interaction with 67LR, promotes tumor cell aggressiveness; the investigation was based on: (i) the previous demonstration that soluble 67LR, as well as a 20-amino-acid peptide corresponding to the 67LR laminin binding site, changes the conformation of laminin upon interaction with this adhesion molecule and (ii) the known relevance of microenvironment remodeling by the tumor, leading to structural modification of extracellular matrix components in tumor progression. MDAMB231 breast carcinoma cells plated on peptide G-treated laminin-1 exhibited a polygonal array of actin filament bundles compared with cells seeded on native laminin-1 which presented the actin bundles organized as multiple cables parallel to margins. Furthermore, in cells seeded on peptide G-treated laminin-1, 67LR was distinct from the alpha6 integrin subunit in filopodia protrusions in addition to colocalizing with this integrin in focal adhesion plaques as it occurs when cells are plated on native laminin-1. In addition to differences in tumor cell adhesion and migration found in cells exposed to peptide G-treated vs native laminin-1, breast carcinoma cells seeded on modified laminin-1 showed a 6-fold increase in invasion capability compared with cells seeded on unmodified laminin-1. Alterations in actin organization as well as adhesion, migration and especially invasion observed in MDAMB231 cells in the presence of peptide G-treated laminin-1 were even found in MDAMB231 cells that, after selection for 67LR high expression, were seeded on native laminin-1. As the 67LR shedding is proportional to its expression level, these findings indicate a role for 67LR in changing laminin structure. Expression analysis of 97 genes encoding proteins that mediate cell matrix interactions, revealed significant differences between cells exposed to modified vs unmodified laminin-1 in 19 genes, 17 of which--including those encoding alpha3 integrin, extracellular matrix protein 1, proteolytic enzymes (such as MT1-MMP, stromelysin-3 and cathepsin L) and their inhibitors--were up-modulated in cells treated with modified laminin-1. Zymogram analysis clearly indicated a significant increase in the activity of the gelatinolytic enzyme MMP-2 in the culture supernatant from cells exposed to modified laminin-1, without an increase in mRNA abundance as observed in microarray analysis. Invasiveness of tumor cells conditioned by modified laminin-1, evaluated as the capability to cross Matrigel basement, was significantly more inhibited by MMPinhibitor TIMP-2 than invasiveness induced by native laminin-1. Taken together, our findings indicate that the role of 67LR in tumor aggressiveness rests in its ability to modify laminin-1 thereby activating proteolytic enzymes that promote tumor cell invasion through extracellular matrix degradation.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Laminina/metabolismo , Receptores de Laminina/fisiologia , Sítios de Ligação , Neoplasias da Mama/metabolismo , Adesão Celular , Movimento Celular , Matriz Extracelular/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Laminina/química , Laminina/efeitos dos fármacos , Invasividade Neoplásica
19.
Cell Mol Life Sci ; 61(23): 2965-78, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15583858

RESUMO

HER2 (human epidermal growth factor receptor-2; also known as erbB2) and its relatives HER1 (epidermal growth factor receptor; EGFR), HER3 and HER4 belong to the HER family of receptor tyrosine kinases. In normal cells, activation of this receptor tyrosine kinase family triggers a rich network of signaling pathways that control normal cell growth, differentiation, motility and adhesion in several cell lineages. The first tumor studied for an alteration of the HER2 oncogene is breast carcinoma, and so far the majority of studies have been performed on this oncotype. Although involvement of HER2 as a cause of human cell transformation needs to be further investigated, overexpression of the HER2 oncogene in human breast carcinomas has been associated with a more aggressive course of disease. It has been suggested that this association depends on HER2-driven proliferation, vessel formation and/or invasiveness; however, poor prognosis may not be directly related to the presence of the oncoprotein on the cell membrane but instead to the breast carcinoma subset identified by HER2 overexpression and characterized by a peculiar gene expression profile, as recently identified. HER2-positive tumors were recently shown to benefit from anthracyclin treatment and to be resistant to endocrine therapy. Despite the fact that many pathways interacting with HER2 are still not fully understood, this tyrosine kinase receptor is, to date, a promising molecule for targeted therapy.


Assuntos
Neoplasias/metabolismo , Neoplasias/terapia , Receptor ErbB-2/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Western Blotting , Transformação Celular Neoplásica , Progressão da Doença , Humanos , Imuno-Histoquímica , Imunoterapia , Inflamação , Ligantes , Camundongos , Microscopia de Fluorescência , Modelos Biológicos , Dados de Sequência Molecular , Mutação , Células NIH 3T3 , Prognóstico , Estrutura Terciária de Proteína , Proteínas Tirosina Quinases/metabolismo , Receptor ErbB-2/metabolismo , Transdução de Sinais
20.
Int J Biol Markers ; 19(3): 213-20, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15503823

RESUMO

Dendritic cells (DCs) are the most potent antigen-presenting cells of the immune system capable of initiating immune responses to antigens. It is also well documented that cancer patients often experience anergy against tumor antigens. In this study we selected the best protocol for inducing the production of antibodies against the HER2 oncoprotein using DCs to overcome anergy. Murine DCs were pulsed in vitro, using different protocols, with recombinant HER2 fused to a human Fc (in order to improve DC antigen uptake) and were used to vaccinate mice. The obtained results indicate that antigen-pulsed DCs can induce an antibody response and that adding CpG after antigen pulsing greatly increases anti-HER2 antibody production.


Assuntos
Anticorpos Antineoplásicos/imunologia , Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Células Dendríticas , Células Dendríticas/imunologia , Animais , Anticorpos Antineoplásicos/classificação , Formação de Anticorpos , Linfócitos B/imunologia , Neoplasias da Mama/imunologia , Linhagem Celular Tumoral , Células Cultivadas , Citocinas/biossíntese , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/metabolismo , Feminino , Humanos , Switching de Imunoglobulina/imunologia , Isotipos de Imunoglobulinas/biossíntese , Isotipos de Imunoglobulinas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Receptor ErbB-2/imunologia , Receptores Fc/imunologia , Receptores Fc/metabolismo
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