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1.
Pathol Oncol Res ; 21(2): 477-85, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25367072

RESUMO

The correct identification of HER2-positive cases is a key point to provide the most appropriate therapy to breast cancer (BC) patients. We aimed at investigating the reproducibility and accuracy of HER2 expression by immunohistochemistry (IHC) in a selected series of 35 invasive BC cases across the pathological anatomy laboratories in Tuscany, Italy. Unstained sections of each BC case were sent to 12 participating laboratories. Pathologists were required to score according to the Food and Drug Administration (FDA) four-tier scoring system (0, 1+, 2+, 3+). Sixteen and nineteen cases were HER2 non-amplified and amplified respectively on fluorescence in situ hybridization. Among 192 readings of the 16 HER2 non-amplified samples, 153 (79.7%) were coded as 0 or 1+, 39 (20.3%) were 2+, and none was 3+ (false positive rate 0%). Among 228 readings of the 19 HER2 amplified samples, 56 (24.6%) were scored 0 or 1+, 79 (34.6%) were 2+, and 93 (40.8%) were 3+. The average sensitivity was 75.4%, ranging between 47% and 100%, and the overall false negative rate was 24.6%. Participation of pathological anatomy laboratories performing HER2 testing by IHC in external quality assurance programs should be made mandatory, as the system is able to identify laboratories with suboptimal performance that may need technical advice. Updated 2013 ASCO/CAP recommendations should be adopted as the widening of IHC 2+ "equivocal" category would improve overall accuracy of HER2 testing, as more cases would be classified in this category and, consequently, tested with an in situ hybridisation method.


Assuntos
Neoplasias da Mama/metabolismo , Regulação Neoplásica da Expressão Gênica , Imuno-Histoquímica/métodos , Imuno-Histoquímica/normas , Controle de Qualidade , Receptor ErbB-2/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Reações Falso-Positivas , Feminino , Humanos , Hibridização in Situ Fluorescente/métodos , Hibridização in Situ Fluorescente/normas , Itália , Patologia Clínica/normas , Guias de Prática Clínica como Assunto/normas , Receptor ErbB-2/genética , Reprodutibilidade dos Testes , Estados Unidos
2.
Histol Histopathol ; 27(9): 1175-81, 2012 09.
Artigo em Inglês | MEDLINE | ID: mdl-22806904

RESUMO

Tumours of perivascular epithelioid cells (PEComas) are a heterogeneous group of uncommon mesenchymal neoplasms which exhibit a peculiar immunohistochemical co-expression of muscle and melanocytic markers. PEComas occur at various visceral and soft tissue sites, generally with a benign clinical course. Nevertheless, there has been evidence of cases having an unfavourable outcome, thus prompting investigation of pathological criteria for malignancy. A sclerosing variant of PEComa, more frequently encountered in the retroperitoneum of middle-aged women, has been reported. Prognosis has generally been regarded as favourable and complete surgical excision appears to be adequate treatment. To the best of our knowledge, only two cases of sclerosing PEComa displayed high-grade malignant morphology and were associated with adverse outcome. An additional case of retroperitoneal sclerosing PEComa with a two-year follow-up and indolent behaviour is herein described. Light and electron microscopy were performed, along with immunohistochemical analysis. Further studies are needed to clarify the histogenesis and to predict the biological behaviour of this uncommon entity.


Assuntos
Neoplasias de Células Epitelioides Perivasculares/patologia , Neoplasias Retroperitoneais/patologia , Idoso , Feminino , Humanos , Esclerose/patologia
3.
Int J Androl ; 33(6): 784-93, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20088946

RESUMO

The treatment of advanced prostate cancer (CaP) with androgen deprivation therapy inevitably renders the tumours castration resistant and incurable. Under these conditions, neuroendocrine differentiation (NED) of CaP cells occurs and neuropeptides released by neuroendocrine cells facilitate tumour progression. Pharmacological strategies aiming to prevent or delay NED during androgen ablation could, therefore, increase the effectiveness of the therapy. Mechanisms and pathways inducing NED in CaP are poorly understood and data are often discordant. In the present study, we used several CaP cell lines (androgen-responsive: LNCaP, PC3-AR, 22RV1 and -irresponsive: DU145 and PC3) to evaluate NED after androgen deprivation or treatment with epidermal growth factor (EGF). NED was determined by neuron-specific enolase and chromogranin A expression and by the occurrence of morphological changes in the cells. Androgen-deprivation conditions induced NED in LNCaP and PC3-AR, but not in 22Rv1, PC3 and DU145 cells. LNCaP and PC3-AR cells also became resistant to thapsigargin-induced apoptosis. In all the AR-positive cell lines, androgen deprivation caused a decrease in androgen receptor expression indicating that it is downregulated irrespective of NED induction. Treatment with EGF induced NED in DU145 cells and the EGF receptor inhibitor gefinitib prevented the process. On the contrary, no effect of EGF was demonstrated in LNCaP or 22Rv1 cells. CaP cell lines did not respond univocally to treatments inducing NED, suggesting that studies on this topic should be performed in a wide spectrum of cell models which can be more indicative of the tumour variability in vivo.


Assuntos
Androgênios/farmacologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB , Gefitinibe , Humanos , Masculino , Células Neuroendócrinas/citologia , Fosfopiruvato Hidratase/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Quinazolinas/farmacologia , Receptores Androgênicos
4.
J Endocrinol Invest ; 32(7): 590-6, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19494719

RESUMO

BACKGROUND: The recently identified TMPRSS2: ERG fusion gene is a candidate oncogene for prostate cancer (PCa). SUBJECTS AND METHODS: We have tested for the presence of this gene in tumor samples from 84 patients who had radical prostatectomy in 1998-2000. Sixty patients (group A) had surgery only; 24 patients (group B) received androgen ablation therapy for 3 months before surgery. The occurrence of the rearrangement was evaluated by RT-PCR and by fluorescent in situ hybridization analysis. RESULTS: A TMPRSS2:ERG fusion gene was present and expressed, as demonstrated by RT-PCR, in 84% of patients in group A and in 54% of patients in group B (p=0.01). The presence of TMPRSS2:ERG transcripts and the levels of ERG RNA, measured by quantitative Real Time-PCR, did not correlate significantly with clinical and pathologic characteristics of the tumors. In patients of group A, but not in those of group B, ERG expression showed a negative correlation with the Gleason score (p=0.0001). Histochemical analysis showed that ERG expression is limited to tumor cells, and in group A patients (but not in group B patients) it is limited to those glands that express TMPRSS2:ERG. CONCLUSION: The lower proportion of patients expressing TMPRSS2: ERG in group B suggests that androgen ablation inhibits the expression of TMPRSS2:ERG. Moreover, in group B, but not in group A, patients with expression of the fusion gene had earlier prostate specific antigen recurrence (p=0.007). Although preliminary, the data indicate that tumors in which pre-surgery androgen ablation fails to suppress expression of the fusion gene have a higher risk of recurrence.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Proteínas de Fusão Oncogênica/genética , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/genética , Neoplasias da Próstata/prevenção & controle , Neoplasias da Próstata/terapia , Técnicas de Ablação , Idoso , Animais , Fusão Gênica , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Proteínas de Fusão Oncogênica/metabolismo , Prostatectomia , Neoplasias da Próstata/sangue , Recidiva , Resultado do Tratamento
6.
J Chemother ; 20(2): 263-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18467255

RESUMO

Ependymomas are the third most common brain tumor in children. The post surgical management is controversial. There are no convincing data on an effective role for chemotherapy. O(6)-Methylguanine-DNA-Methyltransferase (MGMT) is a DNA repair protein considered to be a chemosensitivity predictor. Hypermethylation of the MGMT gene promoter is an important cause of MGMT inactivation. We evaluated the MGMT gene promoter methylation and the immunohistochemical MGMT protein expression in 12 recurrent anaplastic ependymomas affecting children. Our purpose was to investigate the molecular rationale of the administration of alkylating agents to children affected by recurrent anaplastic ependymomas. All ependymomas lacked MGMT promoter hypermethylation and 9 (75%) showed high MGMT protein expression (>50% tumoral cells). Differences between different recurrences in the same patient were not observed. These results may indicate MGMT as a factor of chemoresistance to alkylating drugs in anaplastic ependymomas and support the uncertainties regarding the actual benefit of chemotherapy for patients with anaplastic ependymomas.


Assuntos
Neoplasias Encefálicas/enzimologia , Metilases de Modificação do DNA/biossíntese , Enzimas Reparadoras do DNA/biossíntese , Ependimoma/enzimologia , Recidiva Local de Neoplasia/enzimologia , Proteínas Supressoras de Tumor/biossíntese , Adolescente , Anaplasia , Neoplasias Encefálicas/patologia , Criança , Pré-Escolar , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Resistencia a Medicamentos Antineoplásicos , Ependimoma/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Recidiva Local de Neoplasia/patologia , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Proteínas Supressoras de Tumor/genética
7.
J Pathol ; 212(4): 440-9, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17597495

RESUMO

Protease-activated receptor (PAR)-1 and PAR-2 are reported to contribute to the fibrotic process in a number of organs, including lung, liver, pancreas, and kidney. The aim of this study was to localize expression and biological activity of PAR-1 and PAR-2 in normal and pathological cutaneous scars. First, we investigated the immunohistochemical expression of PAR-1 and PAR-2 proteins in a series of human normal scars (NS, n = 10), hypertrophic scars (HS, n = 10), and keloids (K, n = 10). Expression of PAR-1 and PAR-2 was observed in all types of scar. Specifically, in HS and K, diffuse PAR-1 and PAR-2 positivity was found in dermal cellular areas composed of myofibroblasts, while no or minor staining was observed in the scattered fibroblasts embedded in abundant extracellular matrix in the context of the more collagenous nodules, irrespective of the type of scar. The hyperplastic epidermis overlying K was also found to be strongly PAR-1 and PAR-2 positive, whilst in most NS and HS the epidermis was faintly to moderately stained. Second, ribonuclease protection assay on paraffin-embedded specimens showed overexpression of PAR-1 and PAR-2 mRNA in K compared to NS and HS. Third, cultured human fibroblasts exposed to TGF-beta1 expressed a myofibroblast phenotype associated with overexpression of PAR-2, while PAR-1 expression was unaffected. Intracellular Ca(2+) mobilization by PAR-2 agonists in myofibroblasts was increased as compared to fibroblasts, whereas the effect of PAR-1 agonists was unchanged. Our in vivo study indicates that PAR-1 and PAR-2 are expressed in cells involved in physiological and pathological scar formation and suggests that in vitro overexpression and exaggerated functional response of PAR-2 may play a role in the function of myofibroblasts in scar evolution from a physiological repair process to a pathological tissue response.


Assuntos
Cicatriz/metabolismo , Receptor PAR-1/metabolismo , Receptor PAR-2/metabolismo , Adolescente , Adulto , Idoso , Cálcio/metabolismo , Células Cultivadas , Cicatriz/patologia , Cicatriz Hipertrófica/metabolismo , Cicatriz Hipertrófica/patologia , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Queloide/metabolismo , Queloide/patologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , Receptor PAR-1/genética , Receptor PAR-2/genética , Pele/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Cicatrização/fisiologia
8.
Oral Dis ; 13(4): 419-25, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17577330

RESUMO

OBJECTIVE: Orofacial granulomatosis (OFG) is a rare condition characterized by non-caseating granulomas in the orofacial region. Protease-Activated Receptors (PARs) play a role in inflammatory diseases in diverse human tissues. The aim of the study was to investigate the expression of PAR-1, PAR-2, MMP-2, MMP-9, COX-1, and COX-2 in tissues taken from OFG patients. METHODS: PAR-1, PAR-2, MMP-2, MMP-9, COX-1, and COX-2 expression was evaluated by immunohistochemistry in biopsies taken from oral Crohn's disease (five cases), Melkersson-Rosenthal syndrome (MRS) (six cases), cheilitis granulomatosa (five cases) and normal oral mucosa (five cases). RESULTS: PAR-1 was observed in mononuclear inflammatory cells in edematous/lichenoid lesions, whereas a strong PAR-2 immunostaining was detected in epithelioid histiocytes and giant cells in granulomatous lesions, irrespective of the clinical features (Crohn vs MRS). MMPs and COX-2 were expressed in the inflammatory component of edematous/lichenoid lesions and markedly overexpressed in granulomatous lesions. COX-1 was weakly and variably expressed in both edematous/lichenoid and granulomatous lesions. CONCLUSION: Thus, PAR-1 and PAR-2 expressions were related to the intensity and type of inflammatory response but not to the type of clinical lesion. Simultaneous overexpression of PARs, MMPs and COXs suggests synergism among these proinflammatory receptors and enzymes.


Assuntos
Granulomatose Orofacial/patologia , Receptor PAR-1/análise , Receptor PAR-2/análise , Adolescente , Adulto , Idoso , Criança , Doença de Crohn/patologia , Ciclo-Oxigenase 1/análise , Ciclo-Oxigenase 2/análise , Edema/patologia , Células Epitelioides/patologia , Feminino , Células Gigantes/patologia , Histiócitos/patologia , Humanos , Leucócitos Mononucleares/patologia , Erupções Liquenoides/patologia , Masculino , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 9 da Matriz/análise , Síndrome de Melkersson-Rosenthal/patologia , Pessoa de Meia-Idade , Doenças da Boca/patologia , Mucosa Bucal/patologia , Estudos Retrospectivos
9.
Br J Cancer ; 94(11): 1637-42, 2006 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-16721373

RESUMO

WEB-2086 -- an antagonist of platelet-activating factor receptor (PAFR) with known anti-inflammatory, antiangiogenic and antileukaemic properties -- also proved to inhibit the proliferation in human solid tumour cell lines of different histology, and with much higher efficacy than in normal fibroblasts. A detailed analysis of WEB-2086 anticancer activity was then performed focusing on breast adenocarcinoma MCF-7 and MDA-MB-231 cells. WEB-2086-treated cells, either expressing (MCF-7) or unexpressing (MDA-MB-231) the oestrogen receptor (ER)alpha, underwent a dose-dependent growth arrest (IC(50)=0.65+/-0.09 and 0.41+/-0.07 mM, respectively) and accumulation in G(0)-G(1) phase. WEB-2086 also induced morphological and functional changes typical of mature mammary phenotype including (i) cell enlargement and massive neutral lipid deposition (best accomplished in MCF-7 cells); (ii) decrease in motility and active cathepsin D levels (mainly observed in highly invasive MDA-MB-231 cells). The expression of ERalpha was neither increased nor reactivated in treated MCF-7 or MDA-MB-231 cells, respectively. WEB-2086-induced differentiation in breast cancer cells involved the upregulation of PTEN, a key tumour suppressor protein opposing tumorigenesis, and was apparently independent of p53, PAFR, peripheral benzodiazepine receptor and ERalpha status. Overall, WEB-2086 can be proposed as an effective antiproliferative and differentiative agent with interesting translational opportunities to treat breast cancers in support to conventional chemotherapy.


Assuntos
Azepinas/toxicidade , Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , Fator de Ativação de Plaquetas/antagonistas & inibidores , Triazóis/toxicidade , Neoplasias da Mama/fisiopatologia , Catepsina D/metabolismo , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Humanos
10.
Anal Biochem ; 354(2): 205-12, 2006 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16729958

RESUMO

The desmoids are a group of rare clinically diverse, deep-seated fibrous neoplasms. The exact etiology is unknown, but several factors are considered to be positively correlated with their development and growth, i.e., genetic and hormonal factors and trauma. These tumors may be sporadic or associated with a genetic disease such as familial adenomatous polyposis (FAP). Devoid of metastatic potential, they tend to form large, infiltrative masses which, if not completely excised, recur repeatedly. Although surgery is widely accepted as the first-line treatment for extra-abdominal and abdominal wall desmoids, a proportion of cases are successfully palliated with either estrogen antagonists (tamoxifen, toremifene, and raloxifene) or nonsteroidal anti-inflammatory drugs. We describe and compare four methods for evaluating the expression of estrogen receptors alpha/beta and COX-1 and COX-2 in desmoid tumor-derived cells and tissues: immunocytochemistry, immunohistochemistry, RT-PCR, and two-color Western blot detection with the Odyssey infrared imaging system. Through this comparative analysis, Western blot with Odyssey was recognized as the best method to analyze the expression particularly of low expressed proteins in desmoid-derived cells. The use of a specific and reliable assessment method becomes fundamental in the evaluation of the presence and modulation of proteins which are important but weakly expressed in these rare tumors.


Assuntos
Fibromatose Agressiva/metabolismo , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/metabolismo , Sequência de Bases , Western Blotting , Ciclo-Oxigenase 1/análise , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/análise , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Receptor alfa de Estrogênio/análise , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/análise , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Fibromatose Agressiva/genética , Expressão Gênica , Humanos , Imuno-Histoquímica , Proteínas de Membrana/análise , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
11.
Clin Neuropathol ; 25(2): 59-66, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16550738

RESUMO

Cyclooxygenase-2 (COX-2) is the inducible form of the enzyme responsible for the first step in the prostaglandin synthesis. COX-2 upregulation is demonstrated in different tumors. COX-2 products may modulate tumoral growth, apoptosis, metastasis, multidrug resistance and angiogenesis. Moreover, the antitumoral effect of the COX inhibitors has been documented. We studied the immunohistochemical expression and the prognostic value of COX-2 on 43 surgical specimens of glioblastoma-affected patients. Furthermore, we evaluated the correlation between the immunohistochemical expression of COX-2 and vascular endothelial growth factor (VEGF). Of the glioblastomas, 63% resulted as COX-2-positive. Median survival of the patients with COX-2-positive lesions was 10 months; median survival of the patients with COX-2 negative glioblastoma was 21 months (NS). All 4 patients who survived longer than 24 months had COX-2 negative lesions (p = 0.017). Concordance between COX-2 and VEGF was documented in 60% of the cases. Our findings show that glioblastoma can immunohistochemically express COX-2 and that its expression is unrelated with VEGF and significantly less frequent in the long survivors. Nevertheless, the absence of statistical correlation with survival time advises further studies on larger series to ascertain the concrete prognostic value of COX-2 in glioblastoma.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Glioblastoma/patologia , Idoso , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Ciclo-Oxigenase 2 , Feminino , Glioblastoma/mortalidade , Humanos , Imuno-Histoquímica , Masculino , Proteínas de Membrana , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida , Fator A de Crescimento do Endotélio Vascular
12.
Int J Gynecol Cancer ; 16(1): 416-22, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16445668

RESUMO

Surgery is the treatment of choice for uterine carcinosarcomas; nevertheless, the poor effect of chemotherapy and radiotherapy represents an insidious problem for patients with metastatic or unresectable disease, and indeed, new therapeutic approaches are clearly required to improve survival of uterine carcinosarcoma patients. The HER-2 oncogene, located on chromosome 17, encodes for a tyrosine kinase growth factor receptor. We analyzed HER-2/neu overexpression by immunohistochemistry in 28 uterine carcinosarcomas. HER-2/neu amplification with fluorescence in situ hybridization (FISH) was tested in positive cases. The expression of HER-2/neu was correlated with disease-free interval and survival (Kaplan-Meier estimates). We observed HER-2/neu overexpression in nine cases (32.1%) and HER-2/neu amplification in all the four HER-2/neu 3+ score positive cases tested by FISH. HER-2/neu expression was not correlated with clinical outcome. Patients with disease limited to the uterus (stages I-II) displayed a significantly better disease-free survival (P= 0.004) and actuarial survival (P= 0.01). Demonstration of HER-2/neu overexpression and amplification in uterine carcinosarcoma may represent the first rationale step for further investigations. Hence, the results of this analysis may support the challenge of a new therapeutic approach, which could test the role of anti-HER-2 (trastuzumab) in patients with advanced or metastatic uterine carcinosarcoma.


Assuntos
Biomarcadores Tumorais/análise , Carcinossarcoma/patologia , Carcinossarcoma/terapia , Neoplasias Uterinas/patologia , Neoplasias Uterinas/terapia , Adulto , Idoso , Biópsia por Agulha , Carcinossarcoma/genética , Carcinossarcoma/mortalidade , Distribuição de Qui-Quadrado , Estudos de Coortes , Feminino , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Genes erbB-2 , Terapia Genética , Humanos , Histerectomia/métodos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Probabilidade , Prognóstico , Estudos Retrospectivos , Sensibilidade e Especificidade , Taxa de Sobrevida , Técnicas de Cultura de Tecidos , Neoplasias Uterinas/genética , Neoplasias Uterinas/mortalidade
13.
Br J Cancer ; 93(7): 781-92, 2005 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-16175187

RESUMO

Recent studies have led to considerable advancement in our understanding of the molecular mechanisms that underlie the relentless cell growth and invasiveness of human gliomas. Partial understanding of these mechanisms has (1) improved the classification for gliomas, by identifying prognostic subgroups, and (2) pointed to novel potential therapeutic targets. Some classes of ion channels have turned out to be involved in the pathogenesis and malignancy of gliomas. We studied the expression and properties of K(+) channels in primary cultures obtained from surgical specimens: human ether a gò-gò related (hERG)1 voltage-dependent K(+) channels, which have been found to be overexpressed in various human cancers, and human ether a gò-gò-like 2 channels, that share many of hERG1's biophysical features. The expression pattern of these two channels was compared to that of the classical inward rectifying K(+) channels, IRK, that are widely expressed in astrocytic cells and classically considered a marker of astrocytic differentiation. In our study, hERG1 was found to be specifically overexpressed in high-grade astrocytomas, that is, glioblastoma multiforme (GBM). In addition, we present evidence that, in GBM cell lines, hERG1 channel activity actively contributes to malignancy by promoting vascular endothelial growth factor secretion, thus stimulating the neoangiogenesis typical of high-grade gliomas. Our data provide important confirmation for studies proposing the hERG1 channel as a molecular marker of tumour progression and a possible target for novel anticancer therapies.


Assuntos
Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Idoso , Sequência de Bases , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Criança , Primers do DNA , Canal de Potássio ERG1 , Canais de Potássio Éter-A-Go-Go , Feminino , Glioblastoma/patologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Técnicas de Patch-Clamp , Canais de Potássio de Abertura Dependente da Tensão da Membrana/antagonistas & inibidores , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
J Chemother ; 16(6): 577-81, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15700850

RESUMO

Many studies have focused on cyclooxygenase-2 (COX-2) alterations as a critical step in the onset and progression of cancer. Moreover, a strong correlation between COX-2 and chemoresistance has been demonstrated in several carcinomas. Recently, COX-2 expression has been observed in uterine carcinosarcoma, osteosarcoma, and rhabdomyosarcoma. We investigated COX-2 expression in chemoresistant uterine leiomyosarcoma in 30 patients who had undergone surgical treatment. COX-2 expression was observed in 13 cases (43.3%). Of the 13 patients with distinct COX-2 positive immunoreactivity uterine leiomyosarcomas, 7 had stage I or II disease and 6 had stage III or IV disease. The expression of COX-2 in uterine stromal malignancies may reveal a therapeutic hypothesis in the context of uterine leiomyosarcoma molecular chemotherapeutic approach.


Assuntos
Leiomiossarcoma/enzimologia , Estadiamento de Neoplasias , Prostaglandina-Endoperóxido Sintases/biossíntese , Neoplasias Uterinas/enzimologia , Adulto , Idoso , Ciclo-Oxigenase 2 , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Leiomiossarcoma/fisiopatologia , Leiomiossarcoma/cirurgia , Proteínas de Membrana , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Neoplasias Uterinas/fisiopatologia , Neoplasias Uterinas/cirurgia
16.
J Chemother ; 15(1): 81-4, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12678420

RESUMO

Uterine malignant stromal tumors are rare neoplasms characterized by fatal prognosis. At the moment no effective systemic treatment is available for metastases or recurrent disease. The drugs employed in advanced neoplasms are iposfamide, doxorubicin or epidoxorubicin, but the clinical response to chemotherapy is poor. Recent studies have shown that cells in gastrointestinal stromal tumors express a growth factor receptor with tyrosine kinase activity termed c-kit. Lately reports of efficacy of a specific anticancer drug with imatinib (ST1571) based on specific molecular abnormalities of proto-oncogene c-kit present in gastrointestinal stromal tumors induced us to identify the c-kit phenotype also in uterine leiomyosarcomas. These data may be useful for treating metastatic uterine leiomyosarcomas with increased c-kit kinase activity.


Assuntos
Antineoplásicos/farmacologia , Leiomiossarcoma/genética , Leiomiossarcoma/patologia , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-kit/biossíntese , Pirimidinas/farmacologia , Neoplasias Uterinas/genética , Neoplasias Uterinas/patologia , Adulto , Idoso , Benzamidas , Feminino , Humanos , Mesilato de Imatinib , Imuno-Histoquímica , Pessoa de Meia-Idade , Fenótipo , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-kit/análise
17.
J Gravit Physiol ; 9(1): P261-2, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15002571

RESUMO

FLG 29.1 cells, cultured at 1xg, are able to switch on a differentiating process only when they are suitably induced by chemical factors. On the contrary, when FLG 29.1 cells are cultured in conditions of gravitational unloading, simulated by a Random Positioning Machine, the switching on of the differentiation process occurs in the absence of any added differentiating agent or any stimulating factor. The phenotypic characterization of the cells and quantitative measures of their bone resorption activity are consistent with a differentiation process through the osteoclastic pathway.

18.
J Oral Pathol Med ; 30(9): 564-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11555161

RESUMO

In this study, we investigated the distribution of the standard form of the CD44 (CD44s) cell adhesion molecule and of its v3 and v6 isoforms in samples of foetal and adult parotid gland tissue, in comparison with samples of parotid gland adenomas and carcinoma ex pleomorphic adenoma. Foetal parotid gland showed CD44s and CD44v3 expression in the peripheral small primordial ducts and acini, while CD44v6 was only focally expressed. Adult parotid gland tissue showed a similar distribution of CD44s and variants, with a predominant expression in acinar structures and a weaker expression at duct level. In parotid gland adenomas, a diffuse and intense expression of CD44s and variants 3 and 6 was observed only in pleomorphic adenomas, while expression of CD44s was prevalent in Warthin's tumour, myoepithelioma and oncocytoma. The malignant areas of carcinoma ex pleomorphic adenoma showed a markedly decreased expression of CD44v3 and CD44v6 in comparison with the adjacent pleomorphic adenoma component. In conclusion, the prevalent expression of CD44s and variants in pleomorphic adenoma in comparison with other adenomas may be related to the abundant extracellular matrix production present in these tumours, while loss of CD44v3 and CD44v6 associated with the onset of carcinoma ex pleomorphic adenoma could promote stromal invasion, eventually contributing to the development of distant metastases.


Assuntos
Receptores de Hialuronatos/imunologia , Glândula Parótida/imunologia , Neoplasias Parotídeas/imunologia , Adenocarcinoma/imunologia , Adenolinfoma/imunologia , Adenoma Pleomorfo/imunologia , Adulto , Feto/imunologia , Humanos , Receptores de Hialuronatos/análise , Receptores de Hialuronatos/química , Técnicas Imunoenzimáticas , Mioepitelioma/imunologia , Isoformas de Proteínas , Distribuição Tecidual
19.
Br J Cancer ; 85(3): 333-6, 2001 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-11487260

RESUMO

We report here a case of a patient affected by endometrial cancer and treated primarily with leuprolide, the surgical approach being unfeasible due to her compromised conditions. The therapy was continued for more than 6 years, and no progression of the disease was observed. During this period, some histological and immunohistochemical evaluations of the tumour (morphology, grading, proliferation and apoptotic index, E-cadherin expression) were performed. Furthermore, the expression of m-RNA for luteinizing-hormone releasing hormone (LHRH) receptors was determined. The results showed a discrepancy between some biological parameters of the tumour and its clinical characteristics. In fact, despite features suggestive of a progression of the cancer (such as the increase of both tumour grading and proliferating capacity (MIB-1), and a fall in the reparative process (appearance of mutated p53, reduced expression of both bcl-2 and c-erb-2) being detected, neither local invasion nor metastatic lesions were clinically observed. This discrepancy might be due to the maintenance of high levels of E-cadhezin. Moreover, since this tumour was shown to express mRNA for LHRH receptors, new evidence is provided about the favourable impact of LHRH analogue treatment in patients affected by endometrial cancer.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos Hormonais/uso terapêutico , Neoplasias do Endométrio/tratamento farmacológico , Leuprolida/uso terapêutico , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Idoso , Biomarcadores Tumorais/metabolismo , Progressão da Doença , Intervalo Livre de Doença , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/patologia , Feminino , Humanos , Proteínas de Neoplasias/metabolismo , RNA Mensageiro/metabolismo , Receptores LHRH/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
J Pathol ; 194(2): 194-200, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11400148

RESUMO

Nitric oxide (NO) is synthesized by nitric oxide synthases (NOS) and plays an important role in tumour growth. In this study, inducible NOS (iNOS) expression was evaluated by immunohistochemistry in 34 melanocytic naevi (13 common melanocytic naevi, six Spitz naevi, and 15 so-called 'dysplastic naevi'), ten cutaneous melanomas in situ, 50 stage I invasive melanomas, and eight subcutaneous metastases of melanoma. In addition, four samples of melanocytic naevi and four samples of invasive melanomas were collected in order to perform western blot and northern blot analysis. By immunohistochemistry, melanocytic naevi never expressed iNOS. Among cases of melanoma in situ, two were negative, seven displayed staining in less than 20% of melanoma cells, and positivity was observed in 21-50% of melanoma cells in only one case. iNOS expression was detected in 46 out of 50 invasive melanomas (92%). Among these cases, 18 showed positivity in less than 20% of melanoma cells, 18 showed positivity in 21-50% of melanoma cells, and ten showed iNOS expression in more than 50% of cells. Statistical analysis revealed a significant difference in iNOS expression between melanocytic naevi and cutaneous melanomas (p<0.001). In addition, iNOS expression was significantly higher in invasive melanomas than in melanomas in situ (p=0.01). Among primary cutaneous melanomas, no significant correlation was found between iNOS expression and histopathological parameters (histotype, level, thickness and presence of regression/inflammatory infiltrate) and disease-specific survival. In subcutaneous melanoma metastases, iNOS expression was diffuse in more than 50% of cells. Statistical analysis revealed that subcutaneous melanoma metastases showed greater iNOS immunoreactivity than invasive melanomas (p=0.02). Molecular analyses confirmed that iNOS mRNA and protein were highly expressed in melanoma samples. In conclusion, iNOS was constantly absent in melanocytic naevi, whereas it was frequently expressed in melanomas, with up-regulation of the enzyme paralleling tumour progression. These data suggest that iNOS may play a role in the malignant transformation of melanocytes and in tumour growth. In addition, iNOS may be useful as an immunohistochemical marker for malignant melanocytic lesions.


Assuntos
Melanoma/enzimologia , Melanoma/secundário , Nevo Pigmentado/enzimologia , Óxido Nítrico Sintase/análise , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Western Blotting/métodos , Distribuição de Qui-Quadrado , Progressão da Doença , Feminino , Humanos , Imuno-Histoquímica/métodos , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Nevo Pigmentado/patologia , Óxido Nítrico Sintase Tipo II , Sensibilidade e Especificidade , Neoplasias Cutâneas/patologia
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