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1.
Cancer Res ; 65(2): 587-95, 2005 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-15695403

RESUMO

Mantle cell lymphoma (MCL) is an aggressive B-cell non-Hodgkin's lymphoma with poor response to therapy and unfavorable prognosis. Here, we show that retinoic acid (RA) isomers significantly inhibit the proliferation of both primary MCL cultures (n = 7) and established cell lines (Granta 519 and SP-53) as shown by [(3)H]thymidine uptake and carboxyfluorescein diacetate succinimidyl ester labeling coupled with cyclin D1 staining. RA induces cell accumulation in G(0)-G(1) together with a marked up-regulation of p27(Kip1) by inhibiting ubiquitination and proteasome-dependent degradation of the protein. The p21(Cip1) inhibitor was also up-regulated by RA in Granta 519 cells, whereas the expression of cyclin D1 is unaffected. Most of RA-induced p27(Kip1) was bound to cyclin D1/cyclin-dependent kinase 4 complexes, probably contributing to the decreased cyclin-dependent kinase 4 kinase activity and pRb hypophosphorylation observed in RA-treated cells. Experiments with receptor-selective ligands indicate that RA receptor alpha cooperates with retinoid X receptors in mediating RA-dependent MCL cell growth inhibition. Notably, RA isomers, and particularly 9-cis-RA, also inhibited the growth-promoting effect induced in primary MCL cells by CD40 activation alone or in combination with interleukin-4. Immunohistochemical analysis showed that significant numbers of CD40L-expressing lymphoid cells are present in lymph node biopsies of MCL patients. These results therefore further strengthen the possibility that triggering of CD40 by infiltrating CD40L+ cells may continuously promote the growth of MCL cells in vivo. On these grounds, our findings that RA inhibits basal MCL proliferation as well as MCL growth-promoting effects exerted by microenvironmental factors make these compounds highly attractive in terms of potential clinical efficacy in this setting.


Assuntos
Antígenos CD40/farmacologia , Interleucina-4/farmacologia , Linfoma de Célula do Manto/tratamento farmacológico , Tretinoína/farmacologia , Idoso , Ligante de CD40/biossíntese , Proteínas de Ciclo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ciclina D1/metabolismo , Quinase 4 Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p21 , Inibidor de Quinase Dependente de Ciclina p27 , Quinases Ciclina-Dependentes/metabolismo , Feminino , Humanos , Linfoma de Célula do Manto/metabolismo , Linfoma de Célula do Manto/patologia , Masculino , Pessoa de Meia-Idade , Complexo de Endopeptidases do Proteassoma/metabolismo , Inibidores de Proteassoma , Proteínas Proto-Oncogênicas/metabolismo , Receptores do Ácido Retinoico/fisiologia , Proteínas Supressoras de Tumor/metabolismo
2.
Oncogene ; 24(15): 2483-94, 2005 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-15735731

RESUMO

Retinoic acid (RA) arrests the growth of EBV-immortalized lymphoblastoid B cell lines (LCLs) by upregulating the cyclin-dependent kinase inhibitor p27Kip1. Here, we show that in LCLs, RA inhibits ubiquitination and proteasome-dependent degradation of p27Kip1, a phenomenon that is associated with downregulation of Thr187 phosphorylation of the protein, whereas the phosphorylation on Ser10 is unaffected. Furthermore, we demonstrate that RA downregulates the expression of the p45Skp2 and Cks1 proteins, two essential components of the SCF(Skp2) ubiquitin ligase complex that target p27Kip1 for degradation. Downregulation of p45Skp2)and Cks1 occurs before the onset of growth arrest and is due to enhanced proteasome-mediated proteolysis of these proteins. Moreover, overexpression of p45Skp2 in DG75 cells prevents p27Kip1 protein accumulation and promotes resistance to the antiproliferative effects of RA. Treatment with Leptomycin B (LMB) blocked the translocation of p27Kip1 to the cytoplasm and prevented its degradation, indicating that CRM1-dependent nuclear export is required for p27Kip1 degradation. The shuttle protein p38Jab1, however, does not accumulate in the nucleus upon LMB treatment, nor does it interact with p27Kip1. Conversely, p45Skp2 is associated with p27Kip1 both in the nucleus and in the cytoplasm, accumulating within the nuclei after exposure to LMB and co-localizing with the exportin CRM1, suggesting a possible involvement of p45Skp2 in CRM1-dependent nuclear export of p27Kip1. These results indicate that downregulation of p45Skp2 is a key element underlying RA-induced p27Kip1 stabilization in B cells, resulting in an impaired targeting of the protein to the ubiquitin-proteasome pathway and probably contributing to the nuclear accumulation of p27Kip1.


Assuntos
Antineoplásicos/farmacologia , Linfócitos B/fisiologia , Proteínas de Ciclo Celular/metabolismo , Proteínas Quinases Associadas a Fase S/metabolismo , Tretinoína/farmacologia , Proteínas Supressoras de Tumor/metabolismo , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p27 , Regulação para Baixo , Genes Supressores de Tumor , Herpesvirus Humano 4 , Humanos , Complexo de Endopeptidases do Proteassoma , Ubiquitina/farmacologia
3.
J Clin Oncol ; 23(22): 5067-73, 2005 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-15968003

RESUMO

PURPOSE: Some infectious agents contributing to lymphomagenesis have been considered targets for new therapeutic strategies. Chlamydia psittaci DNA has been detected in 80% of ocular adnexal lymphomas. The present pilot study was carried out to assess whether C psittaci-eradicating antibiotic therapy is associated with tumor regression in ocular adnexal lymphomas. PATIENTS AND METHODS: Nine patients with C psittaci-positive marginal-zone B-cell lymphoma of the ocular adnexa at diagnosis or relapse were treated with doxycycline 100 mg, bid orally, for 3 weeks. The presence of C psittaci DNA in peripheral-blood mononuclear cells (PBMCs) was also assessed before and after treatment in seven patients. Objective lymphoma regression was assessed 1, 3, and 6 months after therapy conclusion and every 6 months during follow-up. RESULTS: All patients completed antibiotic therapy with excellent tolerability. At 1 month from doxycycline assumption, chlamydial DNA was no longer detectable in PBMCs of all four positive patients. Objective response was complete in two patients, partial response (> 50%) was observed in two patients, and minimal response (< 50%) was observed in three patients. Duration of response in the seven responders was 12+, 29+, 31+, 8+, 7+, 2+, and 1+ months, respectively. CONCLUSION: C psittaci-eradicating antibiotic therapy with doxycycline is followed by objective response in patients with ocular adnexal lymphoma, even after multiple relapses of the disease. A confirmatory, large, phase II trial is warranted to confirm whether this fast, cheap, and well-tolerated therapy could replace other more aggressive strategies as first-line treatment against ocular adnexal lymphomas.


Assuntos
Antibacterianos/uso terapêutico , Chlamydophila psittaci/patogenicidade , Doxiciclina/uso terapêutico , Neoplasias Oculares/tratamento farmacológico , Neoplasias Oculares/microbiologia , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/microbiologia , Psitacose/complicações , Psitacose/tratamento farmacológico , Administração Oral , Idoso , Antibacterianos/administração & dosagem , Chlamydophila psittaci/genética , DNA Bacteriano/análise , Feminino , Humanos , Leucócitos Mononucleares/microbiologia , Masculino , Pessoa de Meia-Idade
4.
Oncogene ; 22(6): 906-18, 2003 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-12584570

RESUMO

In the search for retinoids active against Burkitt's lymphoma (BL), we found that the arotinoid mofarotene (Ro 40-8757) induced strong antiproliferative and apoptotic responses in most established BL cell lines as well as in primary BL cells. Ro 40-8757-induced apoptosis is associated with mitochondrial membrane depolarization, activation of caspase-3 and -9, and enhanced production of reactive oxygen species. These effects were related to a transient drop in intracellular ATP content, probably favored by a downregulation of NADH dehydrogenase subunit-1, a component of the mitochondrial respiratory chain (MRC) Complex I. Inhibition of MRC with thenoyltrifluoroacetone suppressed both the ATP recovery and apoptosis, confirming that the effects of Ro 40-8757 are mediated by changes in mitochondrial function. Compared to EBV-negative lines, EBV-carrying BLs were more resistant to Ro 40-8757-induced apoptosis. EBV infection and ectopic LMP-1 expression increased the resistance of BL cells to Ro 40-8757-induced apoptosis, probably through bcl-2 upregulation. Finally, we also show that 2-methoxyoestradiol, an inhibitor of the scavenger enzymes superoxide dismutases, enhanced Ro 40-8757-mediated apoptosis. These findings provide the rationale for evaluating the clinical efficacy of Ro 40-8757 in BL patients and suggest that the combination of Ro 40-8757 with inhibitors of scavenger enzymes may be a promising therapeutic approach for this aggressive lymphoma.


Assuntos
Antineoplásicos/farmacologia , Linfoma de Burkitt/tratamento farmacológico , Morfolinas/farmacologia , Fosforilação Oxidativa/efeitos dos fármacos , Retinoides/farmacologia , Trifosfato de Adenosina/metabolismo , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Caspases/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Humanos , Ácido Láctico/metabolismo , Potenciais da Membrana/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , NADH Desidrogenase/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/antagonistas & inibidores
5.
Int J Oncol ; 26(4): 945-50, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15753988

RESUMO

Although epidemiologic and experimental data suggest an etiopathogenetic role for both hepatitis C virus (HCV) and Epstein-Barr virus (EBV) infection in development of B-cell non-Hodgkin's lymphoma (NHL), potential interactions between EBV and HCV during progression of B-cell NHL have not yet been fully investigated. In the present study, tumor biopsy specimens from patients with both B-cell NHL and chronic HCV infection (HCV(+)) were analyzed for the presence of EBV-encoded RNA (EBER) by in situ hybridization (ISH). VH and VL gene segments were amplified from tumor biopsy specimen DNA by PCR. EBV infection (EBV(+)) was detected in tumors from 2 of 31 (6%) HCV(+) B-cell NHL patients. Clinical histories of these two EBV(+)/HCV(+) B-cell NHL patients indicated a particularly aggressive course of disease. Chemotherapy failed to induce long lasting remission for either of these EBV(+)/HCV(+) B-cell NHL patients. Amplification of CDR3 of the Ig heavy chain gene from DNA isolated from each EBV(+)/HCV(+) B-cell NHL indicated the presence of monoclonal B-cell expansion. Rearrangement of Ig genes in neoplastic B-cell clones from both EBV(+)/HCV(+) patients was similar to that previously reported for EBV(-)/HCV(+) B-cell NHL patients. Additionally, neoplastic B-cell clones from these two EBV(+)/HCV(+) B-cell NHL patients did not exhibit intraclonal variation. Previous studies have demonstrated that intraclonal variation is common among neoplastic B-cell clones from EBV(-)/HCV(+) patients. EBV infection may have prevented evolution of variant neoplastic B-cell clones by suppressing antibody affinity maturation. Together, these data suggest that EBV infection may cooperate with HCV infection during progression of B-cell NHL in immunocompetent individuals. Such an interaction may accelerate the course of disease in B-cell NHL patients.


Assuntos
Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/patogenicidade , Linfoma de Células B/patologia , Linfoma de Células B/virologia , Linfoma não Hodgkin/patologia , Linfoma não Hodgkin/virologia , Idoso , Transformação Celular Neoplásica , DNA Viral/análise , Progressão da Doença , Feminino , Humanos , Imunocompetência , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico
6.
Dis Markers ; 21(3): 121-6, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16276005

RESUMO

Aim of this study was verifying whether mucin producing colon cancers (CRCs) could develop through a molecular pathway involving microsatellite instability (MSI) and MUC gene alterations. Out of 49 CRCs expressing variable amounts of mucin, 22 (44.9%) were MSI-H and 5 (10.2%) were MSI-L. MUC genes were analyzed by Southern blotting and extra bands were evident in the Variable Number Tandem Repetition (VNTR) regions of MUC2 (5 cases) and MUC5AC (2 cases), but not MUC1 and MUC4 genes. Since the somatic VNTR abnormalities were detected in 6 MSI-H and in 1 MSI-L tumors, they seem to be peculiar of mismatch repair defective CRCs. Our finding suggests that alteration and/or loss of structurally normal MUC genes may be an important step in the neoplastic molecular pathway of a subset of CRCs and that mutations involving VNTR repetitive sequences may exist in MSI tumors as a direct and/or indirect consequence of an inefficient MMR system.


Assuntos
Neoplasias do Colo/genética , Regulação Neoplásica da Expressão Gênica , Repetições de Microssatélites , Mucinas/genética , Pareamento Incorreto de Bases , Southern Blotting , Linhagem Celular Tumoral , Neoplasias do Colo/metabolismo , Reparo do DNA , Sequência de DNA Instável , Humanos , Modelos Genéticos , Mucina-5AC , Mucina-1/genética , Mucina-2 , Mucina-4 , Mucinas/metabolismo , Neoplasias/metabolismo , Reação em Cadeia da Polimerase
7.
BMC Cancer ; 5: 70, 2005 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-15996267

RESUMO

BACKGROUND: The clinical and pathological characteristics and the clinical course of patients with breast cancer and BRCA 1-2 mutation are poorly known. METHODS: From 1997, patients with breast cancer and a family history of breast or ovarian cancer were offered BRCA testing. The clinical and pathological features of patients with known BRCA status were retrospectively assessed and comparisons were made between cancers arising in BRCA positive and BRCA wild type (WT) patients respectively. Type of treatment, pattern of relapse, event (local relapse, contralateral breast cancer, metastases) free and overall survival were also compared in the two groups. Out of the 210 patients tested, 125 had been treated and followed-up at our Institution and were evaluated in this study. RESULTS: BRCA positive patients tended to be more often premenopausal (79% vs 65%) and to have positive lymphnodes (63% vs 49%), poorly differentiated tumours (76% vs 40%--p = 0.002 at univariate analysis, not significant at multivariate analysis) and negative estrogen receptors (43% vs 29%). Treatment was not different in the two groups. In the 86 BRCA-WT patients, the first event was a local relapse in 3 (3%), metachronous contralateral breast cancer in 7 (8%) and distant metastases in 16 (19%). In the 39 BRCA positive patients, the corresponding figures were 3 (8%), 8 (21%) and 3 (8%). There was no difference in event free survival, with a median of 180 months in both groups of patients. At 20 years, projected survival was 85% for BRCA positive patients and 55% for BRCA-WT, but this difference was not statistically significant. CONCLUSION: Although BRCA positive patients have more frequently negative prognostic factors, their prognosis appears to be equal to or better than in patients with BRCA-WT.


Assuntos
Neoplasias da Mama/genética , Genes BRCA1 , Genes BRCA2 , Mutação , Síndromes Neoplásicas Hereditárias/genética , Diferenciação Celular , Intervalo Livre de Doença , Saúde da Família , Feminino , Seguimentos , Humanos , Linfonodos/patologia , Análise Multivariada , Metástase Neoplásica , Pré-Menopausa , Prognóstico , Modelos de Riscos Proporcionais , Recidiva , Fatores de Tempo , Resultado do Tratamento
8.
Clin Cancer Res ; 9(2): 743-8, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12576444

RESUMO

PURPOSE: Gene silencing by hypermethylation plays an important role in proximal colon carcinogenesis. Conversely, DNA hypomethylation has been associated with distal colon cancer (CLC). Methylenetetrahydrofolate reductase (MTHFR) catalyzes the conversion of 5',10'-methylenetetrahydrofolate to 5'-methyl tetrahydrofolate, which serves as methyl donor in the remethylation of homocysteine to methionine. A common MTHFR 677 C-->T polymorphism is characterized by reduced catalytic activity, which affects methionine synthesis and DNA methylation. The aim of the study was to investigate the role of MTHFR 677 C-->T gene polymorphism in the tumorigenesis of proximal and distal CLC in a monoinstitutional group of patients in North Italy. EXPERIMENTAL DESIGN: One-hundred thirty four consecutive proximal and 142 consecutive distal CLC patients, and 279 control subjects without cancer were genotyped for MTHFR using PCR-restriction fragment-length polymorphism analysis. RESULTS: The prevalence of the 677 TT genotype was significantly (P = 0.005) lower in patients with proximal tumors (10 of 134, 7%) than in subjects with distal tumors (28 of 142, 20%). Case/control approach indicated that individuals homozygous for the 677 TT allele had a significantly reduced risk (2.8-fold) (adjusted odds ratio, 0.36; 95% confidence intervals, 0.14-0.91) of developing proximal CLC compared with those harboring the wild-type or heterozygous genotype (677 CC or 677 CT). No significant association between CLC risk and TT genotype was observed in patients with distal tumors (odds ratio, 1.01; 95% confidence interval, 0.48-2.14). CONCLUSIONS: Our findings support a role for MTHFR 677 TT genotype in reducing proximal CLC risk in North Italy.


Assuntos
Neoplasias do Colo/genética , Metilação de DNA , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/genética , Polimorfismo de Nucleotídeo Único , Alelos , Neoplasias do Colo/enzimologia , Neoplasias do Colo/epidemiologia , Citosina , Inativação Gênica , Genótipo , Humanos , Itália/epidemiologia , Metilenotetra-Hidrofolato Redutase (NADPH2) , Prevalência , Valores de Referência , Fatores de Risco , Timina
9.
Hum Mutat ; 20(5): 368-74, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12402334

RESUMO

In this study we examined a series of 52 patients belonging to hereditary nonpolyposis colorectal cancer (HNPCC) or HNPCC-related families, all who had previously tested negative for mismatch repair (MMR) gene point mutations. Southern blot mutational screening of MLH1 and MSH2 genes was carried out with the aim of detecting large genomic rearrangements and of identifying the molecular mechanisms underlying the inactivation of the MMR genes. Three patients had abnormal restriction patterns and were found to carry distinct MLH1 internal deletions. Long-range PCRs identified the loss of DNA tracts spanning exon 6 (about 2.4 kb in proband A-AV20 and 0.8 kb in proband A-PD5) and exon 3 (about 2.5 kb in proband R-RM2). In A-AV20 the breakpoints occurred into identical 33-bp regions in introns 5 and 6 and a mechanism of classical Alu-mediated homologous recombination was evident. Also, in patient A-PD5 the breakpoints were located in these introns, but without direct involvement of repetitive sequences. In patient R-RM2 the breakpoints were located within repetitive L1 elements with poor homology in intron 2 and 3 and the rearranged allele was characterized by a complex insertion deletion (delCCinsACATAGTA), giving rise to a palindromic CTTAACATAGTATGTTAAG sequence in proximity of the fusion site. This study confirms that genomic rearrangements are an important component of the spectrum of MMR mutations. Although Alu repeats are likely to be implicated in the majority of cases, different molecular mechanisms may also be responsible for the observed MLH1 intragenic deletions. In particular, HNPCC resulting from L1-mediated recombination has been identified as a novel mechanism for MMR inactivating mutation.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Proteínas de Neoplasias/genética , Deleção de Sequência , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Alelos , Sequência de Bases , Proteínas de Transporte , Saúde da Família , Genoma Humano , Humanos , Dados de Sequência Molecular , Proteína 1 Homóloga a MutL , Proteínas Nucleares , Alinhamento de Sequência , Homologia de Sequência do Ácido Nucleico
10.
Clin Pharmacokinet ; 43(7): 441-66, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15139794

RESUMO

Etoposide is a derivative of podophyllotoxin widely used in the treatment of several neoplasms, including small cell lung cancer, germ cell tumours and non-Hodgkin's lymphomas. Prolonged administration of etoposide aims for continuous inhibition of topoisomerase II, the intracellular target of etoposide, thus preventing tumour cells from repairing DNA breaks. However, the clinical advantages of extended schedules as compared with conventional short-term infusions remain unclear. Oral administration of etoposide represents the most feasible and economic strategy to maintain effective concentrations of drug for extended times. Nevertheless, the efficacy of oral etoposide therapy is contingent on circumventing pharmacokinetic limitations, mainly low and variable bioavailability. Inhibition of small bowel and hepatic metabolism of etoposide with specific cytochrome P450 inhibitors or inhibition of the intestinal P-glycoprotein efflux pump have been attempted to increase the bioavailability of oral etoposide, but the best results were obtained with daily oral administration of low etoposide doses (50-100 mg/day for 14-21 days). Saturable absorption of etoposide was reported for doses greater than 200 mg/day, whereas lower doses were associated with increased bioavailability, although they were characterised by high inter- and intrapatient variability. Pharmacokinetic parameters such as plasma trough concentration between two oral administrations (C(24,trough)), drug exposure time above a threshold value and area under the plasma concentration-time curve have been correlated with the pharmacodynamic effect of oral etoposide. Pharmacokinetic-pharmacodynamic relationships indicate that severe toxicity is avoided when peak plasma concentrations do not exceed 3-5 mg/L and C(24,trough) is under the threshold limit of 0.3 mg/L. To maintain effective etoposide plasma concentrations during prolonged oral administration, pharmacokinetic variability must be monitored in each patient, taking account of factors from many pharmacokinetic studies of etoposide, including absorption, distribution, protein binding, metabolism and elimination. Dosage reduction is generally useful to avoid haematological toxicity in patients with renal dysfunction (creatinine clearance <50 mL/min). The need for dosage adjustment based on liver function in patients with liver dysfunction is not completely defined, but generally is not indicated in patients with minor liver dysfunction. Adaptive dosage adjustment based on individual pharmacokinetic parameters, estimated using limited sampling strategies and population pharmacokinetic models, is more appropriate. This approach has been used with success in different clinical trials to increase the etoposide dosage, without significantly increasing toxicity. Various pharmacodynamic models have been proposed to guide etoposide oral dosage. However, they lack precision and accuracy and need to be refined by considering other predictor variables in order to extend their application in current clinical practice.


Assuntos
Antineoplásicos Fitogênicos/farmacocinética , Etoposídeo/farmacocinética , Neoplasias/tratamento farmacológico , Administração Oral , Idoso , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/uso terapêutico , Área Sob a Curva , Disponibilidade Biológica , Etoposídeo/administração & dosagem , Etoposídeo/uso terapêutico , Meia-Vida , Humanos , Absorção Intestinal , Relação Estrutura-Atividade , Distribuição Tecidual
11.
Int J Oncol ; 25(2): 345-55, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15254731

RESUMO

IL-6-mediated B-cell growth promotion is involved in the pathogenesis of EBV+ lymphoproliferative disorders of immunosuppressed patients. Since retinoic acid (RA) inhibits the proliferation of EBV-immortalized lymphoblastoid B-cell lines (LCLs), we have investigated the effects of RA on IL-6 signaling in these cells. RA down-regulated IL-6-receptor components with IL-6 agonist activity (membrane and soluble gp80) and increased the levels of soluble gp130, an IL-6 antagonist. These changes, however, were not related to the enhanced production of endogenous IL-6 induced by RA in LCLs. RA-induced modulation of IL-6 receptor components did not abolish IL-6-mediated phosphorylation of gp130, whereas JAK1 and STAT3 phosphorylation and activation induced by IL-6 were markedly inhibited. Overall, the effects of RA resulted in the induction of a complete resistance of LCLs to IL-6-mediated growth promotion. Conversely, RA did not inhibit the constitutive activation of JAK1, TYK2, STAT3 and ERK1/2, ruling out that the JAK/STAT and MAPK pathways may mediate the antiproliferative activity of RA. The finding that RA severely impairs IL-6-dependent signalings in LCLs and inhibits their growth despite the presence of constitutively active JAK/STAT and MAPK cascades provide additional support for a role of RA in the prevention and treatment of EBV-related lymphoproliferative disorders of immunosuppressed patients.


Assuntos
Linfócitos B/virologia , Proteínas de Ligação a DNA/metabolismo , Herpesvirus Humano 4/fisiologia , Interleucina-6/antagonistas & inibidores , Receptores de Interleucina-6/antagonistas & inibidores , Transativadores/metabolismo , Tretinoína/farmacologia , Antígenos CD/análise , Antígenos CD/metabolismo , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Linhagem Celular Transformada , Proliferação de Células/efeitos dos fármacos , Receptor gp130 de Citocina , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Herpesvirus Humano 4/metabolismo , Humanos , Interleucina-6/genética , Interleucina-6/farmacologia , Janus Quinase 1 , Glicoproteínas de Membrana/análise , Glicoproteínas de Membrana/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Tirosina Quinases/metabolismo , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Receptores de Interleucina-6/análise , Receptores de Interleucina-6/genética , Fator de Transcrição STAT3 , Transdução de Sinais/efeitos dos fármacos , Transativadores/genética
12.
Haematologica ; 89(7): 873-4, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15257946

RESUMO

It has been shown that t(14;18)(q32;q21) involving fusion of IGH with MALT1 occurs frequently in mucosa-associated lymphoid tissue (MALT) lymphomas. Results of the present study indicate that the classical form of t(14;18)(q32;q21) involving fusion of IGH with bcl-2 can be detectable in a subset of MALT lymphomas in patients with hepatitis C virus (HCV) infection.


Assuntos
Rearranjo Gênico do Linfócito B , Genes bcl-2/genética , Hepatite C/genética , Linfoma de Zona Marginal Tipo Células B/genética , Linfoma de Zona Marginal Tipo Células B/virologia , Adulto , Idoso , Feminino , Hepatite C/complicações , Humanos , Masculino , Pessoa de Meia-Idade
13.
BMC Cancer ; 4: 11, 2004 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-15040806

RESUMO

BACKGROUND: Fluoropyrimidines such as 5-fluorouracil (5-FU) and 5-fluoro-2'deoxyuridine (FUDR) are among the most effective chemotherapeutic agents for treatment of metastatic colorectal cancer (CRC). Increased expression of thymidylate synthetase (TS) in CRC metastases has been proposed to be an important mechanism of resistance to fluoropyrimidine-based chemotherapy. METHODS: The present study investigated whether TS mRNA levels in liver metastases of 20 CRC patients before treatment with FUDR by hepatic arterial infusion (HAI) correlated with frequency of clinical response or survival duration. RESULTS: Median survival duration of patients with TS mRNA levels above and below the median was 15 and 18 months, respectively (p > 0.05). Clinical response was achieved in 40% of patients with low TS mRNA levels, but in only 20% of patients with high TS mRNA levels (p = 0.01). TS mRNA levels were also measured for liver metastases of 7 of the patients that did not achieve a clinical response. A statistically significant increase in expression of TS mRNA was observed for liver metastases resistant to chemotherapy (21 +/- 14) in comparison to liver metastases of the same patients before chemotherapy (8 +/- 4) (p = 0.03). CONCLUSION: This is the first report to demonstrate increased TS expression in liver metastases from CRC patients resistant to fluoropyrimidine based chemotherapy. These findings are consistent with previous studies indicating that increased TS expression is associated with resistance to fluoropyrimidine-based chemotherapy.


Assuntos
Neoplasias Colorretais , Resistencia a Medicamentos Antineoplásicos , Neoplasias Hepáticas , Proteínas de Neoplasias/análise , Timidilato Sintase/análise , Adulto , Idoso , Antimetabólitos Antineoplásicos/administração & dosagem , Feminino , Floxuridina/administração & dosagem , Humanos , Infusões Intra-Arteriais , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise
14.
Leuk Lymphoma ; 43(4): 747-51, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12153160

RESUMO

Accumulating evidence support a role for hepatitis C virus (HCV) in the pathogenesis of human lymphoproliferative disorders. Clonal expansions of B lymphocytes have been prevalently detected in the bone marrow, in the liver and in the peripheral blood of HCV-infected patients. Epidemiologic studies have associated HCV infection with an increased risk of B-cell lymphoma development, particularly of those with primary localization to organs target of HCV infection. The analysis of the B-cell receptor variable region sequences in sequential phases of HCV-associated lymphomas provided evidence of an ongoing somatic mutation process still present in the neoplastic cells. A restricted repertoire of V, D, J genes was used to assemble the B-cell receptor, and a frequent occurrence of certain gene combinations (V1-69/D3-22/J4 heavy chain with a V3-20 encoded light chain; V3-7/D3/J3 heavy chain with V3-15/J1 light chain; V3-231D3-22/J4 or V4-59/D2-15/J2 with a V3-20 light chain) was observed, thus suggesting a common antigen-binding specificity for these B-cell clones. The high similarity to antibodies with rheumatoid factor (RF) activity as well as to anti-HCV E2 antibodies suggested that HCV, alone or in complex with IgG, could play a pathogenetic role as an exogenous trigger in certain stages of B-cell lymphoproliferation and in certain subsets of B-cell non-Hodgkin's lymphomas (NHLs). The restricted gene repertoire used to assemble the B-cell receptor observed in HCV-associated B-cell NHLs could have important implications as an antigenic target in anti-tumor immunologic therapies.


Assuntos
Linfócitos B/patologia , Hepatite C/complicações , Linfoma de Células B/etiologia , Medula Óssea/patologia , Divisão Celular , Rearranjo Gênico , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Leves de Imunoglobulina/genética , Região Variável de Imunoglobulina/genética , Linfoma de Células B/terapia , Receptores de Antígenos de Linfócitos B/fisiologia
15.
Leuk Lymphoma ; 45(8): 1539-43, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15370204

RESUMO

A lymphoma patient in remission that develops a second lymphoma is frequently assumed to have had a relapse of the original lymphoma. However, the second lymphoma may instead be a new lymphoma with a different clonal origin. Comparison of histological characteristics alone is insufficient in many cases to distinguish new lymphomas from recurrent lymphomas. In contrast, clonal origins of B-cell lymphomas can be reliably compared by VDJ rearrangement analysis of B-cell IgH genes. Simultaneous lymphomas have similarly been analyzed by this technique to determine whether or not both tumors share a common clonal origin. Application of VDJ rearrangement analysis in clinical research has been important for characterizing mechanisms of lymphoma development. Furthermore, this technique has the potential to improve treatment of lymphoma patients because management of recurrent lymphomas differs from that of new lymphomas.


Assuntos
Rearranjo Gênico de Cadeia Pesada de Linfócito B , Região de Junção de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Linfoma de Células B/genética , Recidiva Local de Neoplasia/diagnóstico , Segunda Neoplasia Primária/diagnóstico , Genes de Imunoglobulinas , Humanos , Recidiva Local de Neoplasia/genética , Segunda Neoplasia Primária/genética
16.
Oncol Rep ; 12(2): 457-62, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15254716

RESUMO

(Uridino-diphosphate)glucuronosyl-transferase enzyme 1A1 isoform (UGT1A1) is involved in glucuronidation of antineoplastic drugs such as SN38, the active metabolite of irinotecan, as well as estrogens and their metabolites. UGT1A1*28 polymorphism decreases UGT1A1 expression and could alter estrogens disposition influencing tumour growth in hormone sensitive tissues. The UGT1A1*28 distribution among an ovarian cancer patient (OCP) population of 217 mono-institutional individuals was investigated to clarify its possible involvement in the pathogenesis and chemotherapy of ovarian cancer. Data were compared with those of 205 female healthy blood donors. In 160 patients also the tumour tissue was genotyped to describe the occurrence of loss of heterozygosity (LOH). A PCR based assay followed by automated fragment analysis was used. Odds ratios (OR), and 95% confidence intervals (95% CI), were computed by a multiple logistic regression model using as dependent variable in a case-control or in a case-case approach the histological classification. No significant prevalence of the polymorphism was observed in the cases versus controls. In a case-case approach, a higher frequency of the polymorphism was observed in patients with mucinous tumours (6/11, 54.6%) compared to non-mucinous (30/206, 14.6%) (p=0.009, OR=7.20; 95% CI 2.06-25.19). LOH was observed in 12 cases out of 160 (7.5%) and was associated with non-mucinous tumours, 10 (83.3%) cases determined a retention of the wild-type allele. In conclusion, the prevalence of UGT1A1*28 found in mucinous OCP could suggest a role in the development of specific histologic sub-groups and could become a marker to be considered when planning ovarian cancer chemotherapy.


Assuntos
Camptotecina/análogos & derivados , Glucuronosiltransferase/genética , Neoplasias Ovarianas/genética , Polimorfismo Genético , Antineoplásicos Fitogênicos/farmacologia , Camptotecina/farmacologia , Estrogênios/metabolismo , Feminino , Heterozigoto , Homozigoto , Humanos , Irinotecano , Perda de Heterozigosidade , Razão de Chances , Neoplasias Ovarianas/patologia , Reação em Cadeia da Polimerase , Isoformas de Proteínas , Análise de Regressão
17.
Oncol Rep ; 9(3): 639-44, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11956643

RESUMO

The CAG repeat (CAGn) present in the N-terminal region of the androgen receptor (AR) inversely correlates with AR transactivation activity. The aim of this study was to investigate whether polymorphic variation in the CAGn length is associated with the risk of developing ovarian cancer. Using a case-control study design 121 women with histologically confirmed ovarian cancer and 100 controls (healthy women) were genotyped for AR-CAG length. No marked difference in the mean length of CAGn was observed between ovarian cancer patients and controls. However, when considering patients with positive personal or family history of tumor (PPFHT), the mean lengths of the long allele, the short allele and the average of the 2 alleles were longer than in the controls. Odds ratios (OR) and their corresponding 95% confidence intervals (CI) were computed after allowance for age. We observed an increase in the risk of ovarian cancer, in terms of OR, in women with CAGn >or=22 (OR=2.17, 95% CI:1.10-4.27). The increase of relative risk was particularly high in women with CAGn >or=22 belonging to the PPFHT group: OR=3.52 (95% CI 1.18-10.47). We also found a statistically significant trend (chi2 trend=4.91; p=0.03) towards an increased risk of ovarian cancer with increasing CAGn length (from or=26). Again, a strong association between increase in CAGn and risk of ovarian cancer was observed in PPFHT patients (chi2 trend=6.38; p=0.01). The results suggest that AR-CAG repeat length could play a role as modifier of the ovarian cancer risk conferred by highly penetrant genes rather than itself conferring a low risk.


Assuntos
Neoplasias Ovarianas/genética , Polimorfismo Genético , Receptores Androgênicos/genética , Repetições de Trinucleotídeos , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Itália , Pessoa de Meia-Idade , Sequências Repetitivas de Ácido Nucleico , Fatores de Risco
18.
Tumori ; 88(1): 18-20, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12004844

RESUMO

Endometrial carcinoma (EC) is the second most common tumor in hereditary nonpolyposis colorectal cancer (HNPCC), with an incidence rate of 60% by the age of 70 in mutation carriers. The International Collaborative Group on HNPCC revised the Amsterdam criteria and proposed a new, wider definition including extracolonic cancers. The aim of our study was to evaluate the accuracy of a new definition called Amsterdam criteria II. We updated, reclassified and compared the pedigrees of 29 women, already reported as being affected by EC and having a colorectal cancer familial background, according to the two clinical diagnostic criteria for HNPCC (Amsterdam criteria I, ACI, and Amsterdam criteria II, ACII) after two periods of observation (1990-1995 and 1995-2000). According to ACII the frequency of HNPCC in the population under study increased from 0.9% to 3.7% in the period 1990-1995 and from 3.2% to 3.7% in the period 1995-2000. ACII allowed early detection of HNPCC families and thus made it possible to provide them with a suitable surveillance program and genetic testing.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Proteínas de Ligação a DNA , Neoplasias do Endométrio/diagnóstico , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Idoso , Proteínas de Transporte , Neoplasias Colorretais Hereditárias sem Polipose/genética , Análise Mutacional de DNA , Neoplasias do Endométrio/genética , Feminino , Testes Genéticos , Humanos , Incidência , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS , Proteínas de Neoplasias/genética , Estadiamento de Neoplasias , Proteínas Nucleares , Seleção de Pacientes , Linhagem , Proteínas Proto-Oncogênicas/genética
19.
Tumori ; 89(3): 311-3, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12908789

RESUMO

Platinum-based therapy is considered the standard treatment for patients with advanced ovarian cancer. Carboplatin has a more favorable toxicity profile than cisplatin; however, hypersensitivity reactions to carboplatin have been reported occasionally. We reviewed 112 cases of ovarian cancer treated with carboplatin at our institute to identify the hypersensitivity reactions to this chemotherapeutic agent. Hypersensitivity reactions were documented in nine cases (8%). No deaths occurred, but the reactions were judged severe in three of the 112 patients (2.6%). In our own experience with patients showing idiosyncrasy to carboplatin we observed successful resolution after retreatment with cisplatin. Since patients who relapse after initial treatment with carboplatin often respond to it a second time, it is important to continue this treatment.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Carboplatina/efeitos adversos , Cisplatino/uso terapêutico , Hipersensibilidade a Drogas/etiologia , Neoplasias Ovarianas/tratamento farmacológico , Adenocarcinoma/patologia , Idoso , Carboplatina/uso terapêutico , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Terapia de Salvação , Resultado do Tratamento
20.
Tumori ; 88(5): 400-6, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12487559

RESUMO

AIMS AND BACKGROUND: Preliminary evidence suggests that hepatitis C virus (HCV) might play a pathogenetic role in autoimmune-related, non-malignant B-cell lymphoproliferation, as well as in a subset of B-cell non-Hodgkin's lymphomas (NHLs). With regard to the mechanism(s) by which HCV might favor B-cell expansion and malignant transformation, most data support an indirect pathogenetic role of the virus as an exogenous trigger. A direct oncogenetic role of HCV by direct cell infection and deregulation has only been hypothesized on the basis of the lymphotropism of the virus. METHODS: In this study we investigated the possible HCV infection of NHL B cells by means of sensitive and quantitative polymerase chain reaction (PCR) on affinity-purified neoplastic cells, and by HCV-specific immunohistochemistry and in situ hybridization. RESULTS: HCV infection of neoplastic B cells was documented in only three cases, namely the low-grade B-cell NHLs that arose in the course of mixed cryoglobulinemia syndrome (MC). HCV infection, below one viral genome per cell, was detectable only by PCR. All the remaining low-grade (one case) and high-grade B-cell NHLs (two cases) were HCV uninfected. Previous immunoglobulin gene analyses were consistent with an antigen-driven B-cell lymphoproliferation in the studied cases. CONCLUSIONS: Overall, our data are consistent with an indirect oncogenetic role of HCV in B-cell lymphomagenesis as an exogenous trigger. Infection of B cells by HCV appears possible in some NHL subsets, but the implications remain unknown.


Assuntos
Linfócitos B/patologia , Linfócitos B/virologia , Hepacivirus/isolamento & purificação , Hepatite C/complicações , Linfoma de Células B/virologia , Idoso , Transformação Celular Neoplásica , Transformação Celular Viral , Feminino , Citometria de Fluxo , Hepacivirus/genética , Humanos , Imuno-Histoquímica , Imunofenotipagem , Hibridização In Situ , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , RNA Viral/isolamento & purificação
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