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1.
J Thorac Oncol ; 7(4): 672-80, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22425916

RESUMO

INTRODUCTION: The optimal use of epidermal growth factor receptor (EGFR)-related molecular markers to prospectively identify tyrosine kinase inhibitor (TKI)-sensitive patients, particularly after a previous chemotherapy treatment, is currently under debate. METHODS: We designed a prospective phase II study to evaluate the activity of EGFR-TKI in four different patient groups, according to the combination of molecular (EGFR gene mutations, EGFR gene copy number and protein expression, and phosphorylated AKT expression, pAKT) and clinicopathological (histology and smoking habits) factors. Correlations between molecular alterations and clinical outcome were also explored retrospectively for first-line chemotherapy and EGFR-TKI treatment. RESULTS: Patients who had progressed during or after first-line chemotherapy were prospectively assigned to EGFR-TKI treatment as follows: (G1) EGFR mutation (n = 12); (G2) highly polysomic/amplified EGFR (n = 18); (G3) EGFR and/or pAKT positive (n = 41); (G4) adenocarcinoma/bronchoalveolar carcinoma and no smoking history (n = 15). G1 and G4 had the best and second-best overall response rate (25% and 20%, respectively), whereas the worst outcome was observed in G2 (ORR, 6%; p = 0.05). Disease control was highest in G1 and G4 (>50%) and lowest in G3 (<20%) (p = 0.02). Patients selected by EGFR mutation or clinical parameters (G1 and G4) also had significantly better progression-free survival and overall survival (p = 0.02 and p = 0.01, respectively). Multivariate analysis confirmed the impact of sex, smoking history, EGFR/KRAS mutation, and pAKT on outcomes and allowed us to derive an efficient predictive model. Histology, EGFR mutations, and pAKT were independent predictors of response to first-line chemotherapy at retrospective analysis, whereas pAKT and human epidermal growth factor receptor 2 expression were the only independent predictors of progression-free survival and overall survival. CONCLUSIONS: Selection of patients based on either EGFR mutation or clinical characteristics seems an effective approach to optimize EGFR-TKI treatment in chemotherapy-pretreated non-small-cell lung cancer patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Mutação , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Intervalo Livre de Doença , Receptores ErbB/antagonistas & inibidores , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Masculino , Análise Multivariada , Estudos Prospectivos , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas p21(ras) , Proteínas ras/genética
2.
Blood ; 117(25): 6793-800, 2011 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-21447834

RESUMO

Variant Philadelphia (Ph) chromosome translocations have been reported in 5%-10% of patients with newly diagnosed chronic myeloid leukemia (CML). Variant translocations may involve one or more chromosomes in addition to 9 and 22, and can be generated by 2 different mechanisms, 1-step and 2-step rearrangements, as revealed by fluorescence in situ hybridization. The prognostic significance of the occurrence of variant translocations has been discussed in previous studies. The European LeukemiaNet recommendations do not provide a "warning" for patients with variant translocations, but there is limited information about their outcome after therapy with tyrosine kinase inhibitors. To identify the role of variant translocations in early chronic phase (CP) CML patients treated with imatinib mesylate, we performed an analysis in a large series of 559 patients enrolled in 3 prospective imatinib trials of the Gruppo Italiano Malattie EMatologiche dell'Adulto (GIMEMA) Working Party on CML. Variant translocations occurred in 30 patients (5%). Our data show that the presence of variant translocations has no impact on the cytogenetic and molecular response or on outcome, regardless of the involvement of different mechanisms, the number of involved chromosomes, or the presence of deletions. Therefore, we suggest that patients with variant translocations do not constitute a "warning" category in the imatinib era. This study is registered at www.clinicaltrials.gov as NCT00514488 and NCT00510926.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Cromossomo Filadélfia , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Benzamidas , Análise Citogenética , Feminino , Humanos , Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Masculino , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida , Adulto Jovem
3.
Cancer Genet Cytogenet ; 199(2): 76-80, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20471509

RESUMO

Additional chromosome abnormalities (ACAs) occur in less than 10% of cases at diagnosis of Philadelphia chromosome (Ph)-positive chronic myelogenous leukemia (CML). In some cases, on the basis of the persistence of the ACAs in Ph-negative cells after response to imatinib, a secondary origin of the Ph chromosome has been demonstrated. In this study, the possible prognostic value of this phenomenon was evaluated. Thirty-six Ph-positive CML patients were included in the study. In six patients, ACAs persisted after the disappearance of the Ph. A complete cytogenetic response (CCR) was obtained in five of these six patients, and five of six also had a high Sokal score. In all the other cases, ACAs disappeared together (in cases of response to therapy with imatinib) or persisted with the Ph (in cases of no response to imatinib). In the former cases, the primary origin of the Ph was demonstrated. CCR was obtained in 22 cases (17 with low to intermediate Sokal scores), while no response was observed in 8 patients (5 with a high Sokal score). Sokal score seems to maintain its prognostic value for patients in whom the Ph occurs as a primary event, but not in those in whom it occurs as a secondary one.


Assuntos
Aberrações Cromossômicas , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Cromossomo Filadélfia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Benzamidas , Feminino , Humanos , Mesilato de Imatinib , Cariotipagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Piperazinas/uso terapêutico , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirimidinas/uso terapêutico , Indução de Remissão , Resultado do Tratamento
4.
J Transl Med ; 8: 36, 2010 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-20398370

RESUMO

BACKGROUND: Responsiveness to Cetuximab alone can be mediated by an increase of Epidermal Growth factor Receptor (EGFR) Gene Copy Number (GCN). Aim of this study was to assess the role of EGFR-GCN in advanced colorectal cancer (CRC) patients receiving chemotherapy plus Cetuximab. METHODS: One hundred and one advanced CRC patients (43 untreated- and 58 pre-treated) were retrospectively studied by fluorescence in situ hybridization (FISH) to assess EGFR-GCN and by immunohistochemistry (IHC) to determine EGFR expression. Sixty-one out of 101 patients were evaluated also for k-ras status by direct sequencing. Clinical end-points were response rate (RR), progression-free survival (PFS) and overall survival (OS). RESULTS: Increased EGFR-GCN was found in 60/101 (59%) tumor samples. There was no correlation between intensity of EGFR-IHC and EGFR-GCN (p = 0.43). Patients receiving chemotherapy plus Cetuximab as first line treatment had a RR of 70% (30/43) while it was 18% (10/56) in the group with previous lines of therapy (p < 0.0001). RR was observed in 29/60 (48%) of patients with increased EGFR-GCN and in 6/28 (21%) in those without (p = 0.02). At multivariate analyses, number of chemotherapy lines and increased EGFR-GCN were predictive of response; EGFR-IHC score, increased EGFR-GCN and number of chemotherapy lines were significantly associated with a significant better PFS. Response to therapy was the only prognostic predictive factor for OS. In the 60 patients analyzed for k-ras mutations, number of chemotherapy lines, increased EGFR-GCN and k-ras wild type status predicted a better PFS. CONCLUSION: In metastatic CRC patients treated with chemotherapy plus Cetuximab number of chemotherapy lines and increased EGFR-GCN were significantly associated with a better clinical outcome, independent of k-ras status.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Receptores ErbB/genética , Dosagem de Genes/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais Humanizados , Cetuximab , Neoplasias Colorretais/patologia , Intervalo Livre de Doença , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas p21(ras) , Resultado do Tratamento , Proteínas ras/metabolismo
5.
J Clin Invest ; 119(5): 1093-108, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19363294

RESUMO

The identification of biomarkers that distinguish between aggressive and indolent forms of prostate cancer (PCa) is crucial for diagnosis and treatment. In this study, we used cultured cells derived from prostate tissue from patients with PCa to define a molecular mechanism underlying the most aggressive form of PCa that involves the functional activation of eNOS and HIFs in association with estrogen receptor beta (ERbeta). Cells from patients with poor prognosis exhibited a constitutively hypoxic phenotype and increased NO production. Upon estrogen treatment, formation of ERbeta/eNOS, ERbeta/HIF-1alpha, or ERbeta/HIF-2alpha combinatorial complexes led to chromatin remodeling and transcriptional induction of prognostic genes. Tissue microarray analysis, using an independent cohort of patients, established a hierarchical predictive power for these proteins, with expression of eNOS plus ERbeta and nuclear eNOS plus HIF-2alpha being the most relevant indicators of adverse clinical outcome. Genetic or pharmacologic modulation of eNOS expression and activity resulted in reciprocal conversion of the transcriptional signature in cells from patients with bad or good outcome, respectively, highlighting the relevance of eNOS in PCa progression. Our work has considerable clinical relevance, since it may enable the earlier diagnosis of aggressive PCa through routine biopsy assessment of eNOS, ERbeta, and HIF-2alpha expression. Furthermore, proposing eNOS as a therapeutic target fosters innovative therapies for PCa with NO inhibitors, which are employed in preclinical trials in non-oncological diseases.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Receptor beta de Estrogênio/metabolismo , Regulação Neoplásica da Expressão Gênica/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Neoplasias da Próstata/diagnóstico , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Biomarcadores , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Montagem e Desmontagem da Cromatina/fisiologia , Citoplasma/metabolismo , Inibidores Enzimáticos/farmacologia , Estradiol/farmacologia , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Transportador de Glucose Tipo 1/genética , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Masculino , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Óxido Nítrico Sintase Tipo III/genética , Prognóstico , Regiões Promotoras Genéticas/genética , Neoplasias da Próstata/metabolismo , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/genética , Elementos de Resposta/genética , Telomerase/genética , Telomerase/metabolismo , Análise Serial de Tecidos , Fator A de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética
6.
Anticancer Res ; 27(4C): 2839-44, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17695457

RESUMO

BACKGROUND: Although the majority of endometrial cancer (EC) patients can be cured by surgery, unexpected recurrent disease may also occur in early stage patients. In the present study, whether or not the analysis of multiple biopathological parameters might lead to more accurate predictions of the clinical outcome of EC patients with long-term follow-up (FU) was investigated. PATIENTS AND METHODS: Estrogen and progesterone receptor (ER and PgR) positivity and HER2 overexpression by immunohistochemistry were evaluated. The peritoneal washings (PWs) were analyzed by cytology and immunocytochemistry employing AR-3 and B72.3 monoclonal antibodies. RESULTS: The patients with positive PW and HER2 positive tumors showed shorter overall survival compared to those bearing HER2 negative tumors (p =0.004). HER2 overexpression also influenced the patient outcome in the group with tumors lacking PgR (p = 0.004). At multivariate analysis PgR and HER2 overexpression emerged as independent prognostic factors. CONCLUSION: The combined analysis of these biopathological markers could provide useful information for the selection of patients to be enrolled in innovative therapeutic strategies.


Assuntos
Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/patologia , Receptor ErbB-2/biossíntese , Receptores de Progesterona/biossíntese , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Endométrio/enzimologia , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Cavidade Peritoneal/patologia , Receptores de Estrogênio/biossíntese , Taxa de Sobrevida
7.
Oncologist ; 11(8): 878-86, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16951391

RESUMO

The increasing evidence of trastuzumab efficacy in breast cancer (BC) patients means that an accurate and reproducible evaluation of HER-2 statusis of paramount importance in histological and in cytological samples. Currently, the two main methods used to analyze HER-2 amplification or overexpression are fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC). Although the two methods are strongly correlated for histological tissue, the evaluation of tumor morphology through FISH may be difficult and fluorescence fades quickly. These limitations can be overcome by chromogenic in situ hybridization (CISH), which can visualize the amplification product along with morphological features. In view of this, in the present study, we analyzed the usefulness of CISH on formalin-fixed, paraffin-embedded (FFPE) BC specimens and investigated whether CISH can be a valid technique in the determination of HER-2 status for fine-needle aspirates (FNAs) processed by liquid-based cytology. The results we obtained in a retrospective series of 111 FFPE BC specimens demonstrated good concordance between CISH and IHC and between CISH and FISH. The former concordance was comparable with that observed between FISH and IHC. When CISH was applied to a prospective series of 53 FNAs, from surgically removed BC, our data showed evidence of a higher concordance of results between liquid-based cytology and the companion FFPE tissues using CISH rather than HercepTesttrade mark. Therefore, CISH analysis, which is avaluable and reproducible alternative to FISH for selecting breast cancer patients for trastuzumab therapy, can lower false-positive immunocytochemistry findings in ThinPrep-processed FNAs.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Compostos Cromogênicos , Hibridização In Situ , Receptor ErbB-2/genética , Anticorpos Monoclonais Humanizados , Biópsia por Agulha Fina , Feminino , Amplificação de Genes , Técnicas de Preparação Histocitológica , Humanos , Técnicas Imunoenzimáticas , Hibridização in Situ Fluorescente , Inclusão em Parafina , Estudos Prospectivos , Estudos Retrospectivos , Sensibilidade e Especificidade , Trastuzumab
8.
Mol Cancer Res ; 4(2): 79-92, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16513839

RESUMO

The histopathologic and molecular heterogeneity of prostate cancer and the limited availability of human tumor tissue make unraveling the mechanisms of prostate carcinogenesis a challenging task. Our goal was to develop an ex vivo model that could be reliably used to define a prognostic signature based on gene expression profiling of cell cultures that maintained the tumor phenotype. To this end, we derived epithelial cultures from tissue explanted from 59 patients undergoing radical prostatectomy or cistoprostatectomy because of prostate benign hyperplasia/prostate cancer or bladder carcinoma. Patient selection criteria were absence of hormonal neoadjuvant treatment before surgery and diagnosis of clinically localized disease. Using this unique experimental material, we analyzed expression of 22,500 transcripts on the Affymetrix Human U133A GeneChip platform (Affymetrix, Inc., High Wycombe, United Kingdom). Cultures from normal/hyperplastic tissues with a prevalent luminal phenotype and from normal prostate epithelial tissue with basal phenotype (PrEC) served as controls. We have established a large number of prostate primary cultures highly enriched in the secretory phenotype. From them, we derived an epithelial-restricted transcriptional signature that (a) differentiated normal from tumor cells and (b) clearly separated cancer-derived lines into two distinct groups, which correlated with indolent or aggressive clinical behavior of the disease. Our findings provide (a) a method to expand human primary prostate carcinoma cells with a luminal phenotype, (b) a powerful experimental model to study primary prostate cancer biology, and (c) a novel means to characterize these tumors from a molecular genetic standpoint for prognostic and/or predictive purposes.


Assuntos
Biomarcadores Tumorais/genética , Células Epiteliais/metabolismo , Perfilação da Expressão Gênica , Neoplasias da Próstata/genética , Idoso , Diferenciação Celular , Células Cultivadas , Células Epiteliais/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Prognóstico , Próstata/metabolismo , Prostatectomia , Hiperplasia Prostática/genética , Hiperplasia Prostática/patologia , Neoplasias da Próstata/cirurgia , Células Tumorais Cultivadas
9.
Cancer Lett ; 237(1): 76-82, 2006 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-16002207

RESUMO

Fluorescence in situ hybridization analysis for evaluation of 7, 8, X chromosomes and EGFR, LPL, MYC, AR genes in 79 neoplastic foci from 56 patients with clinically localized prostate cancer was performed. We found aneusomy for chromosome 7, 8 and X in 74/77 (96.1%), 56/76 (73.7%), 26/70 (37.1%) of examined foci respectively. No specimen was amplified for EGFR and AR genes, only 2/71 (2.8%) specimens showed MYC gene amplified. LPL deletion was present in 52/76 (68.4%) specimens. Statistically association between Gleason score and both chromosome 7 aneusomy and 8p21 deletion was present. The frequency of chromosome 7 aneusomy was statistically higher in T3-4 cases than T2c and T2a-T2b ones. We considered as unfavorable a genetic set if aneusomy for at least two chromosomes and one altered gene were present. The percentage of tumors, with unfavorable genetic pattern, increased from 36.4 to 75.0% in those with Gleason >7 and from 40.0 to 73.7% in those with stage T3 or more. These alterations could be considered potent genetic markers adjunctive to conventional prognostic parameters. Our objective was to establish specific genetic profiles which may discriminate favorable and unfavorable genetic prognosis tumors.


Assuntos
Biomarcadores Tumorais/genética , Aberrações Cromossômicas , Cromossomos Humanos Par 7 , Cromossomos Humanos Par 8 , Cromossomos Humanos X , Regulação Neoplásica da Expressão Gênica , Neoplasias da Próstata/genética , Análise Citogenética , Amplificação de Genes , Humanos , Hibridização in Situ Fluorescente , Lipase Lipoproteica/genética , Excisão de Linfonodo , Masculino , Estadiamento de Neoplasias , Prognóstico , Prostatectomia , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-myc/genética
10.
Cancer Chemother Pharmacol ; 57(5): 615-23, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16163541

RESUMO

BACKGROUND: The aim of the study was to assess the toxicity profile, activity in terms of response rate, time to progression, overall survival, and quality of life of pegylated liposomal doxorubicin (PLD) and gemcitabine combination in chemo-naïve and pretreated metastatic breast cancer (MBC) women. METHODS: Patients were eligible if they had disease progression to prior chemotherapy (anthracycline-including or not) for early breast cancer or MBC. Patients received PLD 25 mg/m(2) intravenously on day 1 plus gemcitabine 800 mg/m(2) intravenously on days 1 and 8 of each 21-day cycle. RESULTS: Of 50 patients enrolled, 37 had received prior adjuvant chemotherapy (24 with an anthracycline) and 23 prior chemotherapy for metastatic disease (6 with an anthracycline). Two complete responses and 20 partial responses were achieved in 46 assessable patients (overall response rate: 47.8%). Responses were observed in 14 (46.6%) of 30 patients with previous anthracycline exposure. Median response duration was 7 months, median duration of clinical benefit 8 months, time to progression 7 months. At a median follow-up of 10 months, 79.4% patients were alive at 1 year. No neutropenic complication was observed. Non-hematological toxicities were mild. One patient previously treated with an anthracycline developed a transient decrease (26%) in the left ventricular ejection fraction, with cardiac function recovering within 6 months. CONCLUSION: Because of the non-overlapping toxicity profiles of both PLD and gemcitabine, this combination can be regarded as a reliable therapeutic option for patients who have failed previous treatments, including anthracycline, for MBC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Antraciclinas/uso terapêutico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Progressão da Doença , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Feminino , Humanos , Infusões Intravenosas , Pessoa de Meia-Idade , Polietilenoglicóis/administração & dosagem , Qualidade de Vida , Taxa de Sobrevida , Resultado do Tratamento , Gencitabina
12.
J Cell Physiol ; 204(1): 106-12, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15622519

RESUMO

To determine whether phenotypic field changes occur in tissues adjacent to carcinoma, we assayed, by immunohistochemistry, the expression of HER-2, p53, Fas, and FasL in 72 breast cancers (BC) and multiple autologous peritumoral tissues (PTTs) sampled up to 5 cm distance and in 44 benign breast tumors (BBTs). About 5% and 3% of the PTTs and 4.5% and 6.8% of BBTs showed alterations in HER2 and p53 expression, respectively. Of interest, gene amplification was observed in 50% of HER2 positive PTTs, but not in any HER2 positive BBTs. Fas, highly expressed in BBTs and downregulated in BC, maintained its expression in PTTs, whereas FasL, usually negative in BBTs, was upregulated in BC as well as in the PTTs closest (1 cm) to the invasive lesion. Our data suggest that FasL could be a potential novel biomarker of transformation, which may identify, along with HER2 and p53, precursor lesions in a genetically altered breast tissue.


Assuntos
Neoplasias da Mama/metabolismo , Mama/metabolismo , Glicoproteínas de Membrana/metabolismo , Receptor ErbB-2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Receptor fas/metabolismo , Biomarcadores Tumorais/metabolismo , Mama/citologia , Mama/patologia , Doenças Mamárias/metabolismo , Doenças Mamárias/patologia , Neoplasias da Mama/patologia , Diagnóstico Precoce , Proteína Ligante Fas , Feminino , Humanos , Imuno-Histoquímica , Fenótipo
13.
Clin Cancer Res ; 10(22): 7747-56, 2004 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-15570009

RESUMO

PURPOSE: To investigate the possible existence of an antiapoptotic cross-talk between HER-2 and antiapoptotic Bcl-2 family members. EXPERIMENTAL DESIGN: Bcl-2 and Bcl-XL expression and apoptosis induction were analyzed in HER-2 gene-amplified (BT474) and nonamplified (ZR 75-1) breast cancer cell lines exposed to trastuzumab, alone or in combination with either Bcl-2/Bcl-XL bispecific antisense oligonucleotides (AS-4625) or the small-molecule Bcl-2 antagonist HA14-1. RESULTS: In addition to HER-2 and epidermal growth factor receptor, trastuzumab down-regulated Bcl-2, but not Bcl-XL, protein, and mRNA expression in BT474 cells. Interestingly, trastuzumab-induced down-regulation of HER-2 and Bcl-2 was also observed in three of five and two of three breast cancer patients undergoing trastuzumab treatment, respectively. Despite Bcl-2 down-regulation, however, trastuzumab only marginally increased the rate of apoptosis (7.3 +/- 3.5%). We therefore investigated whether a combination of AS-4625 and trastuzumab might increase proapoptotic efficiency. AS-4625 treatment of BT474 cells decreased both Bcl-2 and Bcl-XL expression, resulting in a 21 +/- 7% net apoptosis induction; the combination of AS-4625 followed by trastuzumab resulted in a significantly stronger induction of apoptosis (37 +/- 6%, P <0.01) that was not observed with the reverse treatment sequence (trastuzumab followed by AS-4625). Similar results were obtained with the Bcl-2 antagonist HA14-1; indeed, exposure of BT474 cells to HA14-1 followed by trastuzumab resulted in a striking proapoptotic synergism (combination index=0.58 +/- 0.18), as assessed by isobologram analysis. CONCLUSIONS: Altogether our findings suggest that combined targeting of HER-2 and Bcl-2 may represent a novel, rational approach to more effective breast cancer therapy.


Assuntos
Anticorpos Monoclonais/farmacologia , Apoptose , Benzopiranos/farmacologia , Regulação para Baixo , Inibidores Enzimáticos/farmacologia , Nitrilas/farmacologia , Oligonucleotídeos Antissenso/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Anticorpos Monoclonais Humanizados , Antineoplásicos/farmacologia , Western Blotting , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Flavonoides/farmacologia , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Transfecção , Trastuzumab , Regulação para Cima , Proteína bcl-X
14.
Haematologica ; 89(9): ECR37, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15377489

RESUMO

Here we describe how we detected the BCR/ABL fusion gene on the short arm of der(9) combining classical GTG banding and Fluorescence In Situ Hybridization (FISH) in a case of chronic myeloid leukemia (CML). To our knowledge, variant translocations involving the short arm of chromosome 9, in literature, are almost rare in chronic myeloid leukemia. It is not clear if this complex genetic translocation represents clonal evolution or a unique, initial presentation variant of the Philadelphia chromosome (Ph).


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mieloide de Fase Crônica/genética , Cromossomo Filadélfia , Adulto , Feminino , Humanos , Hibridização in Situ Fluorescente
16.
Hum Pathol ; 34(3): 214-21, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12673554

RESUMO

A systematic analysis of both tumors and the surrounding urothelium to help identify what lies behind the mechanism of multifocal tumor development has not yet been performed. In this study we investigated chromosome 1, 7, 9, and 17 aneusomy in 25 superficial papillary carcinomas and in 51 tissue samples taken from sites of macroscopically uninvolved urothelium surrounding the tumors, using the fluorescence in situ hybridization method. Our data demonstrated a close genetic relationship between all examined tumors and normal-appearing mucosa. Numeric aberrations of chromosomes 1, 7, 9, and 17 were found to exhibit similar patterns in all analyzed specimens, although with different frequencies.


Assuntos
Carcinoma Papilar/genética , Aberrações Cromossômicas , Análise Citogenética , Neoplasias da Bexiga Urinária/genética , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 17 , Cromossomos Humanos Par 7 , Cromossomos Humanos Par 9 , Corantes Fluorescentes , Humanos , Hibridização in Situ Fluorescente , Indóis , Mucosa/ultraestrutura , Urotélio/ultraestrutura
17.
Oncogene ; 21(19): 3011-9, 2002 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-12082531

RESUMO

c-Myc is involved in the control of telomerase activity through its ability to induce the expression of the catalytic subunit of the enzyme, the human telomerase reverse transcriptase (hTERT). Our aim was to study whether telomerase plays a critical role in c-Myc-dependent tumorigenicity of melanoma cells. By using M14-derived clones, expressing low levels of c-Myc, we demonstrated that the down-regulation of c-Myc reduced cell proliferation rate, cloning efficiency and tumorigenicity and increased the apoptotic rate. Decreased tumorigenic potential correlated with reduced hTERT gene expression, telomerase activity and telomere shortening. Introduction of wild-type hTERT into these cells increased their proliferation rate and partially re-established their tumorigenic potential, at early passages, even though the apoptotic rate of the population remained unaltered. After several in vitro passages, hTERT-mediated cell proliferation made the tumorigenic potential of the c-Myc low-expressing clones comparable to that of the M14 parental line. Over-expression of the mutant biologically inactive hTERT did not drive cells to proliferate. In conclusion, our results demonstrate that the reconstitution of high levels of telomerase activity reverses the low tumorigenicity due to low c-Myc expression.


Assuntos
Melanoma/patologia , Proteínas de Neoplasias/fisiologia , Proteínas Proto-Oncogênicas c-myc/fisiologia , Telomerase/fisiologia , Animais , Apoptose , Divisão Celular , Células Clonais/metabolismo , Células Clonais/patologia , Proteínas de Ligação a DNA , Regulação Neoplásica da Expressão Gênica , Genes myc , Humanos , Melanoma/metabolismo , Camundongos , Camundongos Nus , Proteínas de Neoplasias/genética , Transplante de Neoplasias , Proteínas Proto-Oncogênicas c-myc/deficiência , Proteínas Recombinantes de Fusão/fisiologia , Telomerase/genética , Telômero/ultraestrutura , Células Tumorais Cultivadas/metabolismo , Células Tumorais Cultivadas/patologia , Ensaio Tumoral de Célula-Tronco
18.
Cancer Genet Cytogenet ; 133(1): 66-71, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11890992

RESUMO

The main focus of the present study was to assess the efficacy of interphase cytogenetics using fluorescence in situ hybridization (FISH) as a valid alternative to immunohistochemistry (IHC) in paraffin-embedded tissue sections and/or the efficacy of the combination of the two methods, while, at the same time, aiming to provide additional information on the use of the two methods. For this study, selected breast cancer patients (n=66) were tested for HER-2 gene amplification by FISH. The probe contains DNA sequences specific for the HER-2 human gene locus and hybridizes to the 17q11.2 through q12 region of human chromosome 17. The same samples were tested previously for HER-2 overexpression by two monoclonal antibodies (300G9 and CB11), recognizing an extracellular and an internal domain of gp185(Her-2), respectively. HER-2 overexpression also was evaluated using the HerceptTest Kit (Dako, Milan, Italy). The HerceptTest was performed according to the manufacturer's standard procedures, and results were scored on a 0 to 3+ scale. A total of 34 (51%) of 66 breast tumors enrolled in this study were positive by FISH. Of the 34 cases amplified by FISH, 9 were negative by IHC using both monoclonal antibody (MoAb) 300G9 and MoAb CB11, with a concordance rate from 80.3% to 83.3%. A higher concordance was verified (92.4%) when we used the HerceptTest Kit. Of the 32 cases found negative with the HerceptTest, FISH analysis identified HER-2 gene amplification in more than 10%. Our results indicate that with the combined use of both methods, several amplified samples classified negative by IHC can be used thus improving therapeutic planning for specific therapy with the monoclonal antibody trastuzumab.


Assuntos
Neoplasias da Mama/genética , Receptor ErbB-2/análise , Receptor ErbB-2/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
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