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1.
J Cell Physiol ; 230(12): 3105-14, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26012475

RESUMO

Loss of response to TGF-ß is a central event in the genesis of colorectal cancer (CRC), a disease that, in the majority cases, is refractory to growth inhibition induced by this cytokine. However, inactivating mutations at receptors and transducers from the TGF-ß cascade occur only in approximately half of CRCs, suggesting the involvement of additional mechanisms altering the response to the cytokine. We have recently described the amplification of the 13q31 locus, where the miR-17-92 cluster maps, associated with overexpression of its members. In this study, we address the potential role of miR-20a, from the miR-17-92 cluster, in the suppression of TGF-ß cytostatic response in CRC. Using the poorly tumorigenic and TGF-ß-sensitive FET cell line that expresses low miR-20a levels, we first confirmed that miR-20a downmodulated CDKN1A expression, both at mRNA and protein level, through direct binding to its 3'-UTR. We demonstrated that miR-20a significantly diminished cell response to TGF-ß by preventing its delay of G1/S transition and promoting progression into cell cycle. Moreover, besides modulating CDKN1A, miR-20a blocked TGF-ß-induced transactivation of its promoter without affecting the post-receptor activation of Smad3/4 effectors directly. Finally, miR-20a abrogated the TGF-ß-mediated c-Myc repression, a direct inhibitor of the CDKN1A promoter activation, most likely by reducing the expression of specific MYC-regulating genes from the Smad/E2F-based core repressor complex. Our experiments indicate that miR-20a interferes with the colonic epithelium homeostasis by disrupting the regulation of Myc/p21 by TGF-ß, which is essential for its malignant transformation.


Assuntos
Carcinoma/metabolismo , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , MicroRNAs/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta/farmacologia , Regiões 3' não Traduzidas , Sítios de Ligação , Células CACO-2 , Carcinoma/genética , Carcinoma/patologia , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Inibidor de Quinase Dependente de Ciclina p21/genética , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Células HEK293 , Células HT29 , Humanos , MicroRNAs/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Interferência de RNA , Ativação Transcricional , Transfecção
2.
Mod Pathol ; 28(8): 1074-83, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26022454

RESUMO

Solitary fibrous tumors, which are characterized by their broad morphological spectrum and unpredictable behavior, are rare mesenchymal neoplasias that are currently divided into three main variants that have the NAB2-STAT6 gene fusion as their unifying molecular lesion: usual, malignant and dedifferentiated solitary fibrous tumors. The aims of this study were to validate molecular and immunohistochemical/biochemical approaches to diagnose the range of solitary fibrous tumors by focusing on the dedifferentiated variant, and to reveal the genetic events associated with dedifferentiation by integrating the findings of array comparative genomic hybridization. We studied 29 usual, malignant and dedifferentiated solitary fibrous tumors from 24 patients (including paired samples from five patients whose tumors progressed to the dedifferentiated form) by means of STAT6 immunohistochemistry and (when frozen material was available) reverse-transcriptase polymerase chain reaction and biochemistry. In addition, the array comparative genomic hybridization findings were used to profile 12 tumors from nine patients. The NAB2/STAT6 fusion was detected in all of the tumors, but immunohistochemistry and western blotting indicated that chimeric protein expression was atypical or absent in 9 out of 11 dedifferentiated tumors. The comparative genomic hybridization results revealed that the usual and malignant solitary fibrous tumors had a simple profile, whereas the genome of the dedifferentiated tumors was complex and unstable, and suggested that 13q and 17p deletions and TP53 mutations may be present in malignant lesions before the full expression of a dedifferentiated phenotype. Solitary fibrous tumor dedifferentiation is associated with the loss of chimeric oncoprotein expression, genomic instability, and cell decommitment and reprogramming. The assessment of dedifferentiated solitary fibrous tumors is based on the presence of the fusion transcripts and, in principle, negative STAT6 immunohistochemistry should not rule out a diagnosis of solitary fibrous tumor.


Assuntos
Biomarcadores Tumorais , Fusão Gênica , Instabilidade Genômica , Técnicas de Diagnóstico Molecular , Proteínas Repressoras , Fator de Transcrição STAT6 , Tumores Fibrosos Solitários/diagnóstico , Adulto , Idoso , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Western Blotting , Deleção Cromossômica , Cromossomos Humanos Par 13 , Cromossomos Humanos Par 17 , Hibridização Genômica Comparativa , Análise Mutacional de DNA , Diagnóstico Diferencial , Feminino , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mutação , Fenótipo , Valor Preditivo dos Testes , Proteínas Repressoras/análise , Proteínas Repressoras/genética , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT6/análise , Fator de Transcrição STAT6/genética , Tumores Fibrosos Solitários/química , Tumores Fibrosos Solitários/genética , Tumores Fibrosos Solitários/patologia , Proteína Supressora de Tumor p53/genética , Adulto Jovem
3.
Clin Chem ; 61(1): 278-89, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25411184

RESUMO

BACKGROUND: Determining the transcriptional profile of circulating tumor cells (CTCs) may allow the acquisition of clinically relevant information while overcoming tumor heterogeneity-related biases associated with use of tissue samples for biomarker assessment. However, such molecular characterization is challenging because CTCs are rare and outnumbered by blood cells. METHODS: Here, we describe a technical protocol to measure the expression of >29 000 genes in CTCs captured from whole blood with magnetic beads linked with antibodies against epithelial cell adhesion molecule (EpCAM) and the carcinoma-associated mucin, MUC1, designed to be used for CTC characterization in clinical samples. Low numbers of cells (5-200) from the MCF7 and MDA-MB-468 breast cancer cell lines were spiked in healthy donor blood samples and isolated with the AdnaTest EMT-1/Stem CellSelect kit. Gene expression profiles (GEPs) were obtained with the WG-DASL HT assay and compared with GEPs obtained from RNA isolated from cultured cell lines and unspiked samples. RESULTS: GEPs from samples containing 25 or more spiked cells correlated (r = 0.95) with cognate 100-ng RNA input samples, clustered separately from blood control samples, and allowed MCF7 and MDA-MB-468 cells to be distinguished. GEPs with comparable technical quality were also obtained in a preliminary series of clinical samples. CONCLUSIONS: Our approach allows technically reliable GEPs to be obtained from isolated CTCs for the acquisition of biologically useful information. It is reproducible and suitable for application in prospective studies to assess the clinical utility of CTC GEPs, provided that >25 CTCs can be isolated.


Assuntos
Neoplasias da Mama/genética , Perfilação da Expressão Gênica/métodos , Células Neoplásicas Circulantes/metabolismo , Transcriptoma/genética , Neoplasias da Mama/sangue , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Técnicas de Cultura de Células , Feminino , Ontologia Genética , Estudo de Associação Genômica Ampla , Humanos , Células MCF-7 , Células Neoplásicas Circulantes/patologia
4.
J Oral Pathol Med ; 44(9): 734-45, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25495427

RESUMO

BACKGROUND: Human papillomavirus (HPV)-positive and HPV-negative oropharyngeal squamous cell carcinomas (OSCCs) are two distinct entities. We defined the molecular profiles of druggable receptor tyrosine kinases (RTKs) in both groups. MATERIALS AND METHODS: E5 expression and RTK alterations were studied in 17 HPV-positive and 59 HPV-negative formalin-fixed OSCCs. RTK activation was explored in further 12 frozen OSCCs. RESULTS: The HPV-positive OSCCs showed E5 expression and 33.3% expressed low level of HER2. The HPV-negative OSCCs showed HER2 expression (31.2%), increased HER2 gene copy number (46.51%, P = 0.045) and HER2 activation through HER2/EGFR heterodimerisation; HER3 (51.06%, P = 0.008) and neuregulin (65.63%; P = 0.03) expression, HER3 activation and HER3/EGFR heterodimerisation; and increased IGF-1R copy number (40.50%, P = 0.021), high IGF-1R cDNA values (P = 0.002), IGF-1R activation and expression of IGF1/2 and amphiregulin. PI3KCA mutations/expression/increased gene copy number and PTEN mutations were found in both groups, whereas PTEN gene loss was only observed in the HPV-positive cases. CONCLUSION: Human papillomavirus-positive and HPV-negative OSCC showed different RTK profiles. In HPV-positive cases, it would be interesting to study the expression of E5, which may modulate EGFR turnover and activate VEGF and PDGFRß. In HPV-negative cases, HER3 may be a promising druggable biomarker that deserves further investigation. PI3KCA and PTEN alterations encourage the promising clinical evaluation of PI3K/mTOR inhibitor activity in OSCC, particularly in HPV-positive/PI3KCA-mutated OSCCs because they may be driven by PI3KCA mutation alone.


Assuntos
Carcinoma de Células Escamosas/virologia , Neoplasias Orofaríngeas/enzimologia , Neoplasias Orofaríngeas/virologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/enzimologia , Receptores Proteína Tirosina Quinases/metabolismo , Anfirregulina/genética , Anfirregulina/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/patologia , Humanos , Neoplasias Bucais/patologia , Mutação , Neoplasias Orofaríngeas/patologia , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Papillomaviridae/genética , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptores Proteína Tirosina Quinases/análise , Receptores Proteína Tirosina Quinases/genética , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Fator de Crescimento Transformador alfa/genética , Fator de Crescimento Transformador alfa/metabolismo
5.
Genes Chromosomes Cancer ; 53(10): 875-80, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24965840

RESUMO

Cutaneous melanoma is the most aggressive form of skin cancer, with a complex and heterogeneous aetiology. Deregulation of the mitogen activated protein kinase cascade is common in melanoma, due to activating mutations in the BRAF and NRAS genes. Genetic studies and high-throughput screening technologies have recently identified several somatic mutations affecting different receptor tyrosine kinase (RTK) genes. For the majority of these, however, the contribution to the complexity of melanoma biology has not been assessed. Among these, two novel missense somatic mutations (M379I and R577G) have recently been identified in the gene encoding the neurotrophic RTK NTRK1. The NTRK1 melanoma-associated point mutations were introduced in a NTRK1 expression plasmid. Functional characterization of mutants was assessed after transient and stable transfection in HeLa and NIH3T3 cells, respectively. We showed that M379I and R577G NTRK1 receptors do not display the kinase as constitutively activated and are functionally indistinguishable from the wild-type NTRK1 receptor. Our results indicate that a causative role for M379I and R577G NTRK1 mutations in melanoma development is highly unlikely. This supports the issue that, in parallel to systematic large scale cancer genome screening, functional studies are required to distinguish between mutations that play a causative role in tumor development and others that may only be passenger changes.


Assuntos
Melanoma/genética , Mutação Puntual , Receptor trkA/genética , Neoplasias Cutâneas/genética , Animais , Estudos de Associação Genética , Células HeLa , Humanos , Melanoma/metabolismo , Camundongos , Células NIH 3T3 , Receptor trkA/metabolismo , Neoplasias Cutâneas/metabolismo
6.
Cancer ; 120(6): 885-93, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24323615

RESUMO

BACKGROUND: Although axillary surgery is still considered to be a fundamental part of the management of early breast cancer, it may no longer be necessary either as treatment or as a guide to adjuvant treatment. The authors conducted a single-center randomized trial (INT09/98) to determine the impact of avoiding axillary surgery in patients with T1N0 breast cancer and planning chemotherapy based on biological factors of the primary tumor on long-term disease control. METHODS: From June 1998 to June 2003, 565 patients aged 30 years to 65 years with T1N0 breast cancer were randomized to either quadrantectomy with (QUAD) or without (QU) axillary lymph node dissection; a total of 517 patients finally were evaluated. All patients received radiotherapy to the residual breast only. Chemotherapy for patients in the QUAD treatment arm was determined based on lymph node status, estrogen receptor status, and tumor grade. Chemotherapy for patients in the QU treatment arm was based on estrogen receptor status, tumor grade, and human epidermal growth factor receptor 2 and laminin receptor status. Overall survival (OS) was the primary endpoint. Disease-free survival (DFS) and rate and time of axillary lymph node recurrence in the QU treatment arm were the secondary endpoints. RESULTS: After a median follow-up of >10 years, the estimated adjusted hazards ratio of the QUAD versus QU treatment arms for OS was 1.09 (95% confidence interval, 0.59-2.00; P = .783) and was 1.04 (95% confidence interval, 0.56-1.94; P = .898) for DFS. Of the 245 patients in the QU treatment arm, 22 (9.0%) experienced axillary lymph node recurrence. The median time to axillary lymph node recurrence from breast surgery was 30.0 months (interquartile range, 24.2 months-73.4 months). CONCLUSIONS: Patients with T1N0 breast cancer did not appear to benefit in terms of DFS and OS from immediate axillary lymph node dissection in the current randomized trial. The biological characteristics of the primary tumor appear adequate for guiding adjuvant treatment.


Assuntos
Axila/cirurgia , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Excisão de Linfonodo , Linfonodos/cirurgia , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Laminina/metabolismo , Taxa de Sobrevida , Resultado do Tratamento
7.
Lab Invest ; 93(11): 1232-40, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24018792

RESUMO

The molecular marker of well-differentiated/de-differentiated liposarcomas is MDM2 gene amplification coupled with protein overexpression and wild-type TP53. MDMX is a recently identified MDM2 homolog and its presence in this tumor is unexplored. Our aim was to investigate the role of full-length MDM2 and MDMX proteins and their isoforms in surgical specimens of well-differentiated/de-differentiated liposarcomas in view of Nutlin-3A (a MDM2 inhibitor) treatment. Frozen and matched formalin-fixed, paraffin-embedded material from surgical specimens was examined by means of: (1) fluorescence in situ hybridization to determine MDM2 and MDMX gene copy numbers; (2) RT-PCR and densitometry to analyze alternative splicing forms of mdm2 and mdmx; (3) immunoblotting and immunohistochemistry to assess the corresponding translated proteins; and (4) in vitro and in silico assays to determine their affinity for Nutlin-3A. All these cases showed MDM2 gene amplification with an MDMX disomic pattern. In all cases, the full-length mdm2 transcript was associated with the mdm2-b transcript, with ratios ranging from 0.07 to 5.6, and both were translated into protein; mdmx and mdmx-s were co-transcripted, with ratios ranging from 0.1 to 5.6. MDMX-S was frequently more upregulated than MDMX at both transcriptional and protein level. Each case showed different amounts of mdm2, mdm2-b, mdmx, and mdmx-s transcripts and the corresponding proteins. In vitro assays showed that Nutlin-3A was ineffective against MDM2-B and was unable to disrupt the MDMX/TP53 and MSMX-S/TP53 complexes. Molecular simulations confirmed these in vitro findings by showing that MDM2 has high Nutlin-3A affinity, followed by MDMX-S, MDMX, and MDM2-B. Nutlin-3A is predicted to be a good therapeutic option for well-differentiated/de-differentiated liposarcomas. However, our findings predict heterogeneous responses depending on the relative expression of mdm2, mdm2-b, mdmx, and mdmx-s transcripts and proteins.


Assuntos
Imidazóis/farmacologia , Lipossarcoma/tratamento farmacológico , Lipossarcoma/metabolismo , Proteínas Nucleares/metabolismo , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Processamento Alternativo , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proteínas de Ciclo Celular , Diferenciação Celular , Simulação por Computador , Resistencia a Medicamentos Antineoplásicos/genética , Resistencia a Medicamentos Antineoplásicos/fisiologia , Feminino , Dosagem de Genes , Humanos , Imidazóis/metabolismo , Hibridização in Situ Fluorescente , Lipossarcoma/patologia , Masculino , Pessoa de Meia-Idade , Modelos Moleculares , Simulação de Dinâmica Molecular , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/genética , Piperazinas/metabolismo , Polimorfismo de Nucleotídeo Único , Conformação Proteica , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
8.
Genes Chromosomes Cancer ; 51(2): 111-26, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22045652

RESUMO

To highlight possible similarities and differences in receptor tyrosine kinase (RTK) and downstream signalling activation profiles between clear-cell sarcomas (CCS) and metastatic melanomas (MM), frozen, and paired-matched fixed samples of six CCS with EWSR1 rearrangement (EWSR1+), five CCS without EWSR1 rearrangement (EWSR1-), and seven MM were investigated by means of biochemical, immunohistochemical, FISH, molecular analyses, and immunofluorescence confocal microscopy. Fixed samples of a further 10 CCS and 14 MM were investigated by means of sequencing for BRAF, NRAS, and KRAS mutations and FISH analyses for the gain of chromosomes 22 and 8. RTK analysis of all CCS/MM samples showed activation of short-form (sf) recepteur d'origine nantais (RON) RTK and of PDGFRB, MET, and HER3. Analysis of downstream signaling revealed consistent phosphorylation patterns of PI3K/AKT, RSK, and the mTOR targets S6 and 4EBP1. Analysis of frozen and fixed material from 21 CCS and 21 MM showed the presence of the V600E BRAF mutation in 2/12 EWSR1+ and 3/9 EWSR1- CCS and 9/21 MM and demonstrated a significant (P < 0.001) correlation between the gain of chromosomes 22 and 8 and EWSR1- CCS. Our results show that BRAF mutation can also be present in CCS and support the proposed aberration of chromosomes 22 and 8 as a possibly useful nonrandom hallmark of EWSR1- CCS. Besides, they broaden the spectrum of the similarities of RTK pathway activation between CCS and MM, thus suggesting that new drugs found to be active in melanoma and RON inhibitors could have a role in CCS treatment. © 2011 Wiley Periodicals, Inc.


Assuntos
Biomarcadores Tumorais/metabolismo , Melanoma/secundário , Receptores Proteína Tirosina Quinases/metabolismo , Sarcoma de Células Claras/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Biomarcadores Tumorais/genética , Proteínas de Ligação a Calmodulina/genética , Proteínas de Ligação a Calmodulina/metabolismo , Duplicação Cromossômica , Cromossomos Humanos Par 22 , Cromossomos Humanos Par 8 , Feminino , Expressão Gênica , Humanos , Metástase Linfática , Masculino , Melanoma/genética , Melanoma/metabolismo , Pessoa de Meia-Idade , Fosforilação , Proteína EWS de Ligação a RNA , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Receptores Proteína Tirosina Quinases/genética , Sarcoma de Células Claras/genética , Sarcoma de Células Claras/patologia , Análise de Sequência de DNA , Trissomia , Adulto Jovem
9.
J Mol Cell Biol ; 14(11)2023 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-36460033

RESUMO

Peritoneal metastases (PM) from colorectal cancer (CRC) are associated with poor survival. The extracellular matrix (ECM) plays a fundamental role in modulating the homing of CRC metastases to the peritoneum. The mechanisms underlying the interactions between metastatic cells and the ECM, however, remain poorly understood, and the number of in vitro models available for the study of the peritoneal metastatic process is limited. Here, we show that decellularized ECM of the peritoneal cavity allows the growth of organoids obtained from PM, favoring the development of three-dimensional (3D) nodules that maintain the characteristics of in vivo PM. Organoids preferentially grow on scaffolds obtained from neoplastic peritoneum, which are characterized by greater stiffness than normal scaffolds. A gene expression analysis of organoids grown on different substrates reflected faithfully the clinical and biological characteristics of the organoids. An impact of the ECM on the response to standard chemotherapy treatment for PM was also observed. The ex vivo 3D model, obtained by combining patient-derived decellularized ECM with organoids to mimic the metastatic niche, could be an innovative tool to develop new therapeutic strategies in a biologically relevant context to personalize treatments.


Assuntos
Neoplasias Colorretais , Neoplasias Peritoneais , Humanos , Matriz Extracelular Descelularizada , Peritônio , Neoplasias Peritoneais/metabolismo , Neoplasias Peritoneais/secundário , Neoplasias Peritoneais/terapia , Organoides , Neoplasias Colorretais/metabolismo
10.
J Transl Med ; 9: 158, 2011 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-21943129

RESUMO

BACKGROUND: Gastrointestinal stromal tumors (GISTs) are the most frequent mesenchymal tumors to develop in the digestive tract. These tumors are highly resistant to conventional chemotherapy and only the introduction of imatinib mesylate has improved the prognosis of patients. However, Response Evaluation Criteria in Solid Tumors are inappropriate for assessing tumor response, and the histological/pathological response to imatinib is variable, heterogeneous, and does not associate with clinical response. The effects of imatinib on responding GISTs are still being explored, and few studies correlate the clinical response with the histological response after pharmacological treatment. Recently, apoptosis and autophagy were suggested as possible alternative mechanisms of pharmacological response. METHODS: Here, we used a proteomic approach, combined with other analyses, to identify some molecular stromal components related to the response/behavior of resected, high-risk GISTs after neoadiuvant imatinib therapy. RESULTS: Our proteomic results indicate an elevated concentration of Stem Cell Growth Factor (SCGF), a hematopoietic growth factor having a role in the development of erythroid and myeloid progenitors, in imatinib-responsive tumor areas. SCGFα expression was detected by mass spectrometry, immunohistochemistry and/or western blot and attributed to acellular matrix of areas scored negative for KIT (CD117). RT-PCR results indicated that GIST samples did not express SCGF transcripts. The recently reported demonstration by Gundacker et al. 1 of the secretion of SCGF in mature pro-inflammatory dendritic cells would indicate a potential importance of SCGF in tissue inflammatory response. Accordingly, inflammatory infiltrates were detected in imatinib-affected areas and the CD68-positivity of the SCGF-positive and KIT-negative areas suggested previous infiltration of monocytes/macrophages into these regions. Thus, chronic inflammation subsequent to imatinib treatment may determine monocyte/macrophage recruitment in imatinib-damaged areas; these areas also feature prominent tumor-cell loss that is replaced by dense hyalinization and fibrosis. CONCLUSIONS: Our studies highlight a possible role of SCGFα in imatinib-induced changes of GIST structure, consistent with a therapeutic response.


Assuntos
Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/metabolismo , Fatores de Crescimento de Células Hematopoéticas/metabolismo , Lectinas Tipo C/metabolismo , Piperazinas/uso terapêutico , Proteômica/métodos , Pirimidinas/uso terapêutico , Benzamidas , Western Blotting , Linhagem Celular Tumoral , Eletroforese em Gel de Poliacrilamida , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/patologia , Regulação Neoplásica da Expressão Gênica , Glicosilação , Fatores de Crescimento de Células Hematopoéticas/genética , Humanos , Mesilato de Imatinib , Imuno-Histoquímica , Lectinas Tipo C/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Células Estromais/metabolismo , Células Estromais/patologia
11.
Genes Chromosomes Cancer ; 49(10): 901-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20589936

RESUMO

Treatment success of breast cancer patients with trastuzumab alone or in combination depends not only on HER2/NEU amplification but also on PTEN and PI3K status and efficient cell death programs. In this pilot study, we found a significant association between loss of beclin 1 and HER2/NEU amplification (both on 17q21) in breast cancers. This finding was confirmed in two public copy number microarray datasets. Furthermore, there is a trend associating beclin 1 loss with TP53 mutations, PI3KCA gene gain, and PTEN mutations. Finally, the observation that beclin 1 gene loss predicted a response to trastuzumab alone or in combination with other drugs is worthy of further confirmation in larger cohorts. Our results suggest that, beclin 1 loss may contribute to genome instability and to a defective autophagy that may lead to tumoral cell death in presence of competent apoptosis or senescence pathways.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Neoplasias da Mama/genética , Cromossomos Humanos Par 17/genética , Amplificação de Genes , Perda de Heterozigosidade , Proteínas de Membrana/genética , Receptor ErbB-2/genética , Proteínas Reguladoras de Apoptose/metabolismo , Proteína Beclina-1 , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Humanos , Técnicas Imunoenzimáticas , Proteínas de Membrana/metabolismo , Mutação/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Prognóstico , RNA Mensageiro/genética , Receptor ErbB-2/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
12.
Breast ; 58: 121-129, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34022715

RESUMO

Genetic testing for hereditary breast and ovarian cancer following genetic counseling is based on guidelines that take into account particular features of the personal and family history, and clinical criteria conferring a probability of having a BRCA mutation greater than 10% as a threshold for accessing the test. However, besides reducing mortality and social impact, the extension of screening programs also for healthy family members would allow a huge saving of the rising costs associated with these pathologies, supporting the choice of the "Test" strategy versus a "No Test" one. Analyses of different health care systems show that by applying the "Test" strategy on patients and their families, a decrease in breast and ovarian cancer cases is achieved, as well as a substantial decrease in costs of economic resources, including the costs of the clinical management of early detected tumors. In this review, we analyzed the most recent papers published on this topic and we summarized the findings on the economic evaluations related to breast and ovarian cancer population screenings. These results proved and validated that the population-wide testing approach is a more accurate screening and preventive intervention than traditional guidelines based on personal/family history and clinical criteria to reduce breast and ovarian cancer risk.


Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Análise Custo-Benefício , Detecção Precoce de Câncer , Feminino , Predisposição Genética para Doença , Testes Genéticos , Humanos , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/genética
13.
Hum Mutat ; 31(1): E1052-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19847796

RESUMO

Recently, the SNPs rs11614913 in hsa-mir-196a2 and rs3746444 in hsa-mir-499 were reported to be associated with increased breast cancer risk, and the SNP rs2910164 in hsa-mir-146a was shown to have an effect on age of breast cancer diagnosis. In order to further investigate the effect of these SNPs, we genotyped a total of 1894 breast cancer cases negative for disease-causing mutations or unclassified variants in BRCA1 and BRCA2, and 2760 controls from Germany and Italy. We compared the genotype and allele frequencies of rs2910164, rs11614913 and rs3746444 in cases versus controls of the German and Italian series, and of the two series combined; we also investigated the effect of the three SNPs on age at breast cancer diagnosis. None of the performed analyses showed statistically significant results. In conclusion, our data suggested lack of association between SNPs rs2910164, rs11614913 and rs3746444 and breast cancer risk, or age at breast cancer onset.


Assuntos
Alelos , Neoplasias da Mama/genética , MicroRNAs/genética , Penetrância , Polimorfismo de Nucleotídeo Único/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Alemanha , Humanos , Itália , Pessoa de Meia-Idade , Adulto Jovem
14.
Clin Cancer Res ; 15(3): 1096-104, 2009 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19188185

RESUMO

PURPOSE: Alveolar soft part sarcoma (ASPS) is a rare, chemoresistant soft tissue sarcoma. ASPS harbors the t(17-X) (p11.2;q25) translocation, resulting in the ASPACR1-TFE3 fusion protein, causing MET autophosphorylation and activation of downstream signaling. The tumor vascular pattern prompted us to use sunitinib malate (SM), a tyrosine kinase inhibitor with antiangiogenic properties. EXPERIMENTAL DESIGN: Since July 2007, five patients with progressive metastatic ASPS have been treated with continuous SM 37.5 mg/d on a named basis. Four patients are evaluable for response. In four cases, cryopreserved material was available. Upstream and downstream targets of receptor tyrosine kinase (RTK) pathways, as well as mechanisms of activation, were investigated by biochemical profiles, including human phospho-receptor RTK antibody arrays and immunoprecipitation/Western blotting, molecular analyses, immunohistochemistry, and fluorescence in situ hybridization analyses. RESULTS: After 3 months, two patients had RECIST (response evaluation criteria in solid tumor) partial response, as well as positron emission tomography response and subjective improvement. One had a RECIST stable disease. One progressed and stopped treatment. One patient is still responding after 12 months. The upstream analysis showed activation of all the platelet-derived growth factor receptor (PDGFR) family members, as well as epidermal growth factor receptor, MET families, and RET. Vascular endothelial growth factor receptors (VEGFR1 and VEGFR2) were activated only in one case. The downstream target analysis showed strong activation of phosphatidylinositol 3-kinase/AKT, extracellular signal-regulated kinase 1/2, and mTOR and its targets (S6K and S6). The absence of any upstream mTOR effector deregulation and the presence of RTK cognate ligands support an autocrine-paracrine activation loop mechanism. CONCLUSION: SM may have antitumor activity in ASPS, possibly through a mechanism involving PDGFR and RET. The role of MET, epidermal growth factor receptor, and mTOR, as well as PDGFR inhibition, needs to be further explored.


Assuntos
Indóis/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Pirróis/uso terapêutico , Sarcoma Alveolar de Partes Moles/tratamento farmacológico , Adulto , Avaliação de Medicamentos , Receptores ErbB/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fosforilação , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Sarcoma Alveolar de Partes Moles/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sunitinibe , Serina-Treonina Quinases TOR
15.
Nature ; 431(7008): 525-6, 2004 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-15457249

RESUMO

The protein-kinase family is the most frequently mutated gene family found in human cancer and faulty kinase enzymes are being investigated as promising targets for the design of antitumour therapies. We have sequenced the gene encoding the transmembrane protein tyrosine kinase ERBB2 (also known as HER2 or Neu) from 120 primary lung tumours and identified 4% that have mutations within the kinase domain; in the adenocarcinoma subtype of lung cancer, 10% of cases had mutations. ERBB2 inhibitors, which have so far proved to be ineffective in treating lung cancer, should now be clinically re-evaluated in the specific subset of patients with lung cancer whose tumours carry ERBB2 mutations.


Assuntos
Neoplasias Pulmonares/genética , Mutação/genética , Receptor ErbB-2/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Análise Mutacional de DNA , Ativação Enzimática , Receptores ErbB/química , Receptores ErbB/genética , Gefitinibe , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Modelos Moleculares , Neoplasias/tratamento farmacológico , Neoplasias/genética , Estrutura Terciária de Proteína , Quinazolinas/uso terapêutico , Receptor ErbB-2/química , Receptor ErbB-2/metabolismo
16.
Genes Chromosomes Cancer ; 48(11): 953-62, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19672874

RESUMO

The current multistep carcinogenesis models of colon cancer do not fully capture the genetic heterogeneity of the disease, which is additionally complicated by the presence of passenger and driver genetic alterations. The aim of this study was to select in the context of this significant heterogeneity additional genes functionally related to colon cancer development. High-throughput copy number and gene expression data of 36 microsatellite stable sporadic colon cancers resected from patients of a single institution characterized for mutations in APC, KRAS, TP53 and loss of 18q were analyzed. Genes whose expression correlated with the underlying copy number pattern were selected, and their association with the above listed mutations and overall survival was evaluated. Gain of 20q was strongly associated with TP53 mutation, and overall survival with alterations on 7p, 8p, 13q, 18q, and 20q. An association with 18q loss and gain of 8q24 was also observed. New candidate genes with a potential role in colon cancer are PLCG1 on 20q, DBC1 on 8q21, and NDGR1 on 8p24. In addition, an unexpected pattern of loss and mutability was found in the region upstream of the KRAS gene. By integrating copy number alterations with gene expression and mutations in colon cancer associated genes, we have developed a strategy that identifies previously known molecular features and additional players in the molecular landscape of colon cancer.


Assuntos
Proteína da Polipose Adenomatosa do Colo/genética , Biomarcadores Tumorais/genética , Neoplasias do Colo/genética , Proteínas Proto-Oncogênicas/genética , Proteína Supressora de Tumor p53/genética , Proteínas ras/genética , Proteína da Polipose Adenomatosa do Colo/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Inteligência Artificial , Biomarcadores Tumorais/metabolismo , Instabilidade Cromossômica , Cromossomos Humanos Par 18 , Neoplasias do Colo/metabolismo , Feminino , Dosagem de Genes , Perfilação da Expressão Gênica , Humanos , Perda de Heterozigosidade , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas p21(ras) , Proteína Supressora de Tumor p53/metabolismo , Proteínas ras/metabolismo
18.
BMC Cancer ; 9: 409, 2009 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-19930681

RESUMO

BACKGROUND: Gene expression profiling is moving from the research setting to the practical clinical use. Gene signatures able to correctly identify high risk breast cancer patients as well as to predict response to treatment are currently under intense investigation. While technical issues dealing with RNA preparation, choice of array platforms, statistical analytical tools are taken into account, the tissue collection process is seldom considered. The time elapsed between surgical tissue removal and freezing of samples for biological characterizations is rarely well defined and/or recorded even for recently stored samples, despite the publications of standard operating procedures for biological sample collection for tissue banks. METHODS: Breast cancer samples from 11 patients were collected immediately after surgical removal and subdivided into aliquots. One was immediately frozen and the others were maintained at room temperature for respectively 2, 6 and 24 hrs. RNA was extracted and gene expression profile was determined using cDNA arrays. Phosphoprotein profiles were studied in parallel. RESULTS: Delayed freezing affected the RNA quality only in 3 samples, which were not subjected to gene profiling. In the 8 breast cancer cases with apparently intact RNA also in sample aliquots frozen at delayed times, 461 genes were modulated simply as a function of freezing timing. Some of these genes were included in gene signatures biologically and clinically relevant for breast cancer. Delayed freezing also affected detection of phosphoproteins, whose pattern may be crucial for clinical decision on target-directed drugs. CONCLUSION: Time elapsed between surgery and freezing of samples appears to have a strong impact and should be considered as a mandatory variable to control for clinical implications of inadequate tissue handling.


Assuntos
Biomarcadores Tumorais/análise , Pesquisa Biomédica/métodos , Neoplasias da Mama/genética , Perfilação da Expressão Gênica/métodos , Manejo de Espécimes/métodos , Pesquisa Biomédica/normas , Feminino , Congelamento , Perfilação da Expressão Gênica/normas , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Manejo de Espécimes/normas , Tempo
19.
Clin Cancer Res ; 14(6): 1726-33, 2008 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18347173

RESUMO

PURPOSE: Currently available clinicopathologic prognostic factors are imperfect predictors of clinical course in advanced-stage epithelial ovarian cancer patients. New molecular predictors are needed to identify patients with higher risk of relapse or death from disease. In a retrospective study, we investigated the prognostic impact of activated leukocyte cell adhesion molecule (ALCAM) expression in epithelial ovarian cancer. EXPERIMENTAL DESIGN: We analyzed the effect of cell-anchorage loss on ALCAM cellular localization in vitro and assessed ALCAM expression by immunohistochemistry in a series of 109 well-characterized epithelial ovarian cancer patient samples. Chi-square test, Kaplan-Meier method, and Cox proportional hazard analyses were used to relate ALCAM cellular localization to clinical-pathologic parameters and to overall survival (OS) rate. RESULTS: Loss of epithelial ovarian cancer cell anchorage was associated both in vitro and in vivo with decreased ALCAM membrane expression. In vivo, ALCAM was localized to cell membrane in normal surface ovarian epithelium, whereas in 67% of the epithelial ovarian cancer samples, membrane localization was decreased or even lost, and the molecule was mainly expressed in cytoplasm. Median OS in this group of patients was 58 months, whereas a median OS was not yet reached in patients with ALCAM membrane localization (P = 0.036, hazard ratio [HR] = 2.0, 95% confidence interval [CI] 1.1 to 3.5). In a multivariate Cox regression model including all the available clinicopathologic variables, loss of ALCAM membrane expression was an independent factor of unfavorable prognosis (P = 0.042, HR = 2.15, 95% CI: 1.0 to 4.5). CONCLUSIONS: Decreased/lost ALCAM membrane expression is a marker of poorer outcome in epithelial ovarian cancer patients and might help to identify patients who could benefit from more frequent follow-up or alternative therapeutic modalities.


Assuntos
Antígenos CD/metabolismo , Carcinoma/diagnóstico , Carcinoma/mortalidade , Moléculas de Adesão Celular Neuronais/metabolismo , Proteínas Fetais/metabolismo , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Carcinoma/metabolismo , Adesão Celular/fisiologia , Membrana Celular/metabolismo , Citoplasma/metabolismo , Regulação para Baixo , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/metabolismo , Prognóstico , Análise de Sobrevida , Distribuição Tecidual , Células Tumorais Cultivadas
20.
Tumori ; 95(2): 133-41, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19579856

RESUMO

AIMS AND BACKGROUND: Italian performance in cancer research from 2000 to 2007 was assessed and compared to that of the other 19 wealthiest countries in the world which carry out the bulk of cancer research. METHODS: Performance was evaluated quantitatively as the number of publications in 125 journals indexed as 'oncological' by Journal Citation Reports and qualitatively as the total impact factor (TIF). Number of publications and TIF were adjusted for the population and gross domestic product (GDP) of each country. The Scopus database was used as publication source. RESULTS: Italy ranked 5th, with the US ranking 1st, over the entire study period for number of cancer publications, which increased over that period. Italy ranked 4th in 2006-2007 for GDP-adjusted and 5th for population-adjusted publication number, loosing ground in the GDP-adjusted ranking and gaining ground in the population-adjusted ranking over the study period. When the quality of research publications was considered, in 2006-2007 Italy was in 5th place for crude TIF (US 1st), in 4th place for GDP-adjusted TIF (Sweden 1st), and in 6th place for population-adjusted TIF (Sweden 1st). Over the study period, Italy was stable for crude and population-adjusted TIF but declined somewhat for GDP-adjusted TIF. CONCLUSIONS: Italy's performance in cancer research over the eight years to 2008 was better than expected considering its GDP and population. Nevertheless, the slight decline evidenced by the present study should induce scientists and policy makers to find ways to reverse the situation.


Assuntos
Jornalismo Médico , Neoplasias , Apoio à Pesquisa como Assunto/economia , Pesquisa/estatística & dados numéricos , Animais , Bibliometria , Humanos , Itália , Fator de Impacto de Revistas
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