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1.
Lung Cancer ; 151: 69-75, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33248711

RESUMO

OBJECTIVES: Tumor mutation screening is standard of care for patients with stage IV NSCLC. Since a couple of years, widespread NGS approaches used in routine diagnostics to detect driver mutations such as EGFR, KRAS, BRAF or MET allows the identification of other alterations that could modulated the intensity or duration of response to targeted therapies. The prevalence of co-occurring alterations that could affect response or prognosis as not been largely analyzed in clinical settings and large cohorts of patients. Thanks to the IFCT program "Biomarkers France", a collection of samples and data at a nation-wide level was available to test the impact of co-mutations on first line EGFR TKI in patients with EGFR mutated cancers. MATERIALS AND METHODS: Targeted NGS was assessed on available (n = 208) samples using the Ion AmpliSeq™ Cancer Hotspot Panel v2 to screen for mutations in 50 different cancer genes. RESULTS: This study showed that PTEN inactivating mutations, ATM alterations, IDH1 mutations and complex EGFR mutations were predictors of short PFS in patients with a stage 4 lung adenocarcinoma receiving first line EGFR TKI and that PTEN, ATM, IDH1 and KRAS mutations as well as alterations in the MAPK pathway were related to shorter OS. CONCLUSION: These findings may lead to new treatment options in patients with unfavorable genotypes to optimize first line responses.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Inibidores de Proteínas Quinases , Proteínas Mutadas de Ataxia Telangiectasia , Biomarcadores , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , França/epidemiologia , Humanos , Isocitrato Desidrogenase , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , PTEN Fosfo-Hidrolase , Inibidores de Proteínas Quinases/uso terapêutico
3.
Ann Oncol ; 28(11): 2715-2724, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28945865

RESUMO

BACKGROUND: EGFR mutations cause inconsistent response to EGFR tyrosine-kinase inhibitors (TKI). To better understand these features, we reviewed all cases of EGFR-mutated non-small-cell lung cancer collected in the Biomarkers France database. PATIENTS AND METHODS: Of 17 664 patients, 1837 (11%) with EGFR-mutated non-small-cell lung cancer were retrospectively analyzed for clinical and molecular characteristics. Results were correlated with survival and treatment response for the 848 stage IV patients. RESULTS: EGFR exon 18, 19, 20 and 21 mutations were found in 102 (5.5%), 931 (51%), 102 (5.5%) and 702 (38%) patients, respectively. Over 50% of exon 18 and 20 mutated patients were smokers. The median follow-up was 51.7 months. EGFR mutation type was prognostic of overall survival (OS) versus wild-type {exon 19: hazard ratio (HR)=0.51 [95% confidence interval (CI): 0.41-0.64], P < 0.0001; exon 21: HR = 0.76 (95% CI: 0.61-0.95), P = 0.002; exon 20: HR = 1.56 (95% CI: 1.02-2.38), P = 0.004}. EGFR mutation type was prognostic of progression-free survival versus wild-type [exon 19: HR = 0.62 (95% CI: 0.49-0.78), P < 0.0001; exon 20: HR = 1.46 (95% CI: 0.96-2.21), P = 0.07]. First-line treatment choice did not influence OS in multivariate analysis. First-line TKI predicted improved progression-free survival versus chemotherapy [HR = 0.67 (95% CI: 0.53-0.85), P = 0.001]. OS was longer for del19 versus L858R, which was associated with better OS compared with other exon 21 mutations, including L861Q. TKI improved survival in patients with exon 18 mutations, while chemotherapy was more beneficial for exon 20-mutated patients. CONCLUSION: EGFR mutation type can inform the most appropriate treatment. Therapeutic schedule had no impact on OS in our study, although TKI should be prescribed in first-line considering the risk of missing the opportunity to use this treatment.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/genética , Neoplasias Pulmonares/patologia , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/antagonistas & inibidores , Seguimentos , França , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
5.
Med Oncol ; 29(3): 1765-72, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21953054

RESUMO

Gastrointestinal stromal tumors (GISTs) are the most common human sarcoma. Most of the data available on GISTs derive from retrospective studies of patients referred to oncology centers. The MolecGIST study sought to determine and correlate clinicopathological and molecular characteristics of GISTs. Tumor samples and clinical records were prospectively obtained and reviewed for patients diagnosed in France during a 24-month period. Five hundred and ninety-six patients were included, of whom 10% had synchronous metastases. GISTs originated from the stomach, small bowel or other site in 56.4, 30.2 and 13.4% of cases, respectively. The main prognostic markers, tumor localization, size and mitotic index were not independent variables (P < 0.0001). Mutational status was determined in 492 (83%) patients, and 138 different mutations were identified. KIT and PDGFRA mutations were detected in 348 (71%) and 74 (15%) patients, respectively, contrasting with 82.8 and 2.1% in patients with advanced GIST (MetaGIST) (P < 0.0001). Further comparison of localized GISTs in the MolecGIST cohort with advanced GISTs from previous clinical trials showed that the mutations of PDGFRA exon18 (D842V and others) as well as KIT exon11 substitutions (W557R and V559D) were more likely to be seen in patients with localized GISTs (odds ratio 7.9, 3.1, 2.7 and 2.5, respectively), while KIT exon 9 502_503dup and KIT exon 11 557_559del were more frequent in metastatic GISTs (odds ratio of 0.3 and 0.5, respectively). These data suggest that KIT and PDGFRA mutations and standardized mitotic count deserve to be investigated to evaluate the relapse risk of GISTs.


Assuntos
Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/patologia , Mutação , Metástase Neoplásica/genética , Proteínas Proto-Oncogênicas c-kit/genética , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Idoso , Análise Mutacional de DNA , Feminino , Humanos , Masculino , Oncologia/normas , Pessoa de Meia-Idade , Metástase Neoplásica/patologia
6.
Br J Cancer ; 103(2): 165-70, 2010 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-20588273

RESUMO

BACKGROUND: Preliminary data indicate that the molecular epidemiology of localised gastrointestinal stromal tumour (GIST) may be different from that of advanced GIST. We sought to investigate the molecular epidemiology of sarcomas, including GIST, in the Rhone-Alpes region in France. PATIENTS AND METHODS: A prospective and exhaustive study in the Rhone-Alpes Region in France to assess the precise incidence of primary sarcomas with systematic centralised pathological review and molecular analysis was conducted for 2 consecutive years. RESULTS: Among 760 patients with a confirmed diagnosis of sarcoma, 131 (17%) had a GIST. The majority of patients had gastric primaries (61%). Mutational analysis could be performed in 106 tumour samples (74%), and 71 (67%) had exon 11 mutations. PDGFRA mutations were found in 16% of cases, which is twice as high as previously reported for advanced GIST. CONCLUSION: Data indicate that PDGFRA mutations in localised GIST may be twice as high as what was previously reported in patients with advanced disease. This finding may have important consequences for patients offered adjuvant imatinib, although most of these tumours are in the low-risk group.


Assuntos
Tumores do Estroma Gastrointestinal/epidemiologia , Tumores do Estroma Gastrointestinal/genética , Sarcoma/epidemiologia , Sarcoma/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , França/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Mutação , Estudos Prospectivos , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Medição de Risco
7.
Br J Cancer ; 103(4): 482-5, 2010 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-20664593

RESUMO

BACKGROUND: Imatinib induces responses and disease stabilisations in non-resectable patients with aggressive fibromatosis (AF). The precise target of imatinib in AF and predictive factors for response to treatment are unknown. METHODS: We investigated factors potentially predictive of response to imatinib in a series of 40 patients with progressive AF included in a phase II trial of imatinib: we tested the presence of KIT exon 10 variant (M541L), the expression of imatinib-sensitive kinases and cell cycle proteins by immunohistochemistry (IHC), and other clinical and biological factors. RESULTS: Of 10 patients for whom DNA could be extracted, 3 had a KIT exon 10 variant (30%), with no correlation with response or progression-free survival (PFS). The expression of other imatinib targets (PDGFRA/B, macrophage colony-stimulating factor receptor (M-CSFR)) and of downstream components of the cell cycle, cell proliferation and proliferation pathway (cyclin D1, ERK, MEK 1-2) did not correlate with PFS. Pre-treatment lymphopenia (<1500/microl) and tumour size >120 mm correlated with shorter PFS in univariate and multivariate analyses. CONCLUSION: Our findings show that a baseline biological characteristic of the patient is the major parameter influencing response to imatinib in aggressive fibromatosis. Tumour characteristics, including the presence of a KIT exon 10 M541L variant, may influence tumour control but this needs to be confirmed and better explained.


Assuntos
Biomarcadores Tumorais/análise , Fibromatose Agressiva/tratamento farmacológico , Proteínas Proto-Oncogênicas c-kit/análise , Adulto , Idoso , Benzamidas , Feminino , Fibromatose Agressiva/terapia , Humanos , Mesilato de Imatinib , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Piperazinas , Prognóstico , Pirimidinas , Resultado do Tratamento , Adulto Jovem
8.
Bull Cancer ; 97(6): 629-41, 2010 Jun.
Artigo em Francês | MEDLINE | ID: mdl-20504759

RESUMO

Sarcomas comprise a heterogeneous group of mesenchymal neoplasms. They can be grouped into 3 general categories, soft tissue sarcoma, visceral and primary bone sarcoma, which have different staging and treatment approaches. Soft tissue sarcomas are typically classified on the basis of genetic alterations and light-microscopic examination of hematoxylin-eosin-stained tissue, in which recognizable morphological characteristics of normal tissues are identified. Sarcomas are further characterized by histologic grade. The 3 most important prognostic variables are grade, size, and location of the primary tumor. This review includes a discussion of both soft tissue sarcomas (unclassified sarcoma, liposarcoma, leiomyosarcoma, synovial sarcoma, dermatofibrosarcoma protuberans, angiosarcoma, Kaposi sarcoma, gastrointestinal stromal tumor, rhabdomyosarcoma, ...) and primary bone sarcomas (osteosarcoma, Ewing sarcoma and chondrosarcoma). The approach to a patient with a sarcoma begins with a biopsy that obtains adequate tissue for diagnosis without interfering with subsequent optimal definitive surgery. Subsequent treatment depends on the specific type of sarcoma. Due to the absence of clear knowledge for incidence rate, we conducted in 2005 and 2006 an exhaustive analysis of all diagnosed cases in the Rhône-Alpes region. Because sarcomas are relatively uncommon yet comprise a wide variety of different entities, second opinion was systematically performed for all included cases.


Assuntos
Neoplasias Ósseas/epidemiologia , Sarcoma/epidemiologia , Neoplasias de Tecidos Moles/epidemiologia , Adulto , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Criança , Feminino , França/epidemiologia , Humanos , Incidência , Masculino , Fatores de Risco , Sarcoma/genética , Sarcoma/patologia , Neoplasias de Tecidos Moles/genética , Neoplasias de Tecidos Moles/patologia
9.
J Clin Pathol ; 59(12): 1300-4, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16731593

RESUMO

AIMS: To clarify the role of beta-catenin in digestive endocrine carcinogenesis, a large and representative series of gastroenteropancreatic endocrine tumours was analysed in order to determine the incidence and pattern of beta-catenin changes and to analyse the clinical and histological characteristics of the tumours presenting immunohistochemically detectable changes in beta-catenin expression. METHODS: 229 cases of gastroenteropancreatic endocrine tumours (stomach, 11; duodenum and ampulla, 29; jejunum and ileum, 51; appendix, 13; colon and rectum, 17; and pancreas, 108) were studied by immunohistochemistry to assess the pattern of distribution of beta-catenin (membranous, cytoplasmic or nuclear). DNA was analysed to detect mutations in exon 3 of the CTNNB1 gene. RESULTS: The distribution of immunoreactive beta-catenin protein was membranous in 164 cases, cytoplasmic in 58 cases and nuclear in seven cases. No mutation was detected in exon 3 of the CTNNB1 gene in any case. The seven cases with nuclear accumulation of beta-catenin were large tumours (mean size 44 (standard deviation (SD) 18.5) mm) with metastases, including liver metastases in five cases, high Ki-67 index (mean 34% (SD 16.5%)) and cyclin D1 overexpression; p53 accumulation was detected in six cases. Five patients died of disease; the mean (SD) survival was 13.6 (4.8) months. CONCLUSIONS: Immunohistochemically detectable nuclear accumulation of beta-catenin is infrequent in gastroenteropancreatic endocrine tumours and is usually not associated with mutations in CNNTB1 exon 3. Changes in beta-catenin expression are late events in digestive endocrine carcinogenesis, associated with tumour progression and dissemination.


Assuntos
Neoplasias do Sistema Digestório/metabolismo , Neoplasias das Glândulas Endócrinas/metabolismo , Proteínas de Neoplasias/metabolismo , beta Catenina/metabolismo , Adulto , Idoso , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Análise Mutacional de DNA , DNA de Neoplasias/genética , Neoplasias do Sistema Digestório/genética , Progressão da Doença , Neoplasias das Glândulas Endócrinas/genética , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , beta Catenina/genética
10.
Morphologie ; 84(265): 31-8, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11048296

RESUMO

Decreased E-cadherin expression assessed by immunohistochemistry correlates with poor survival of bladder and prostate cancer patients. The clinical usefulness of this parameter should therefore be evaluated in a large scale prospective study. In proximal kidney tubule and in its derived tumours cadherin-6 seems to take over E-cadherin function. Impaired E-cadherin function leads to increased invasive capacity of the cells. It has been shown that defective function can result from several mechanisms: mutation of the gene, alteration of transcription, post translational modifications or changes in the interaction of E-cadherin with cytoskeleton anchoring proteins: the catenins. A major mechanism leading to decreased E-cadherin expression in tumours lies in decreased transcription of the gene. Hence, a better understanding of the regulation of E-cadherin transcription might open avenues for therapy by restoring a normal expression.


Assuntos
Caderinas/biossíntese , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/biossíntese , Neoplasias Urogenitais/metabolismo , Caderinas/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/patologia , Cromossomos Humanos Par 16/genética , Proteínas do Citoesqueleto/biossíntese , Proteínas do Citoesqueleto/genética , Feminino , Humanos , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Tábuas de Vida , Masculino , Proteínas de Neoplasias/genética , Prognóstico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , RNA Mensageiro/biossíntese , RNA Neoplásico/biossíntese , Análise de Sobrevida , Transcrição Gênica , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia , Neoplasias Urogenitais/genética , Neoplasias Urogenitais/mortalidade , Neoplasias Urogenitais/patologia , alfa Catenina
11.
Eur Urol ; 38(3): 331-8, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10940709

RESUMO

OBJECTIVES: Cell-cell adhesion mediated by cadherins is tight and stable and preserves tissue integrity. However, during tissue remodeling, e.g., development, adhesion may be modified for morphogenic movement. Similarly, during carcinogenesis, cell-cell adhesion might alter leading to a more aggressive phenotype. Here we describe cadherin expression patterns in developing, adult, and neoplastic kidney. METHODS: Fetal kidneys were obtained from voluntary terminations of pregnancy and 43 renal cell carcinomas (RCC) and normal kidneys were obtained at nephrectomy. Frozen sections of these specimens were stained immunohistochemically using antibodies against E-cadherin (ECD), cadherin-6 (CAD6) and alpha-catenin (alpha-cat). RESULTS: CAD6 was expressed in lower and middle limbs of the S-shaped bodies, structures that will develop into renal proximal tubules, which also express CAD6. Similarly, ECD was expressed in the upper limb of S-shaped bodies, structures which will develop into distal and collecting tubules which also express ECD. Twenty-four out of 43 RCC (55.8%) displayed a CAD6 (+)/ECD (-)/alpha-cat (+) phenotype. The other RCC had a CAD6 (+)/ECD (+)/alpha-cat (+) phenotype (10/43, 23.2%), CAD6 (-)/ECD (+)/alpha-cat (+) phenotype (3/43, 7.0%) or CAD6 (-)/ECD (-)/alpha-cat (+) phenotype (6/43, 14.0%), respectively. On the other hand, normal, heterogeneous, or absent expression of CAD6 was seen in 19, 15, and 9 tumors, whereas in 11, 2, and 30 tumors, respectively, ECD expression was seen. Survival curves showed that abnormal CAD6 expression correlated with a poor prognosis rather than abnormal ECD expression. CONCLUSIONS: The combination of cadherin expression appeared to be fixed relatively early during kidney organogenesis. Since almost all RCC originate from proximal tubular epithelial cells (CAD6 (+)/ECD (-)/alpha-cat (+)), only 55. 8% of RCC retained the original cadherin phenotype. Alterations in expression of these molecules may be a reflection of the degree of dedifferentiation from the primary organ. In addition, scoring of expression patterns including heterogeneous expression could be a useful tool to estimate the malignancy potential of the tumor.


Assuntos
Caderinas/biossíntese , Carcinoma de Células Renais/metabolismo , Proteínas do Citoesqueleto/biossíntese , Neoplasias Renais/metabolismo , Rim/embriologia , Rim/metabolismo , Humanos , alfa Catenina
12.
Int J Cancer ; 83(5): 591-5, 1999 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-10521791

RESUMO

The involvement of E-cadherin in the progression of carcinoma is supported by a large number of studies showing an inverse relationship between E-cadherin immunoreactivity and tumor aggressiveness. However, the mechanisms leading to decreased E-cadherin immunoreactivity are still unclear. Comparison of Northern blotting and immunohistochemistry in a series of 49 frozen bladder tumors revealed that, in 16 of 23 tumors with abnormal staining, clear mRNA down-regulation occurred. In the 7 cases without mRNA down-regulation, no structural anomalies of E-cadherin could be detected by Southern blotting, Western blotting or PCR-SSCP. Western blotting confirmed that, in 6 of these tumors, E-cadherin was down-regulated at the protein level. This down-regulation was accompanied by down-regulation of alpha-catenin and, to a lesser extent, of beta- or gamma-catenin. However, Northern-blot analysis indicated that expression of the 3 catenins is maintained at the mRNA level. Thus our data show that, in bladder tumors, mRNA down-regulation accounts for about two thirds (16/23) of tumors with abnormal staining and that post-transcriptional down-regulation of E-cadherin occurs in 6/23 of these tumors.


Assuntos
Caderinas/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células de Transição/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias da Bexiga Urinária/metabolismo , Northern Blotting , Caderinas/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células de Transição/genética , Progressão da Doença , Regulação para Baixo , Humanos , Imuno-Histoquímica , Perda de Heterozigosidade , Proteínas de Neoplasias/genética , RNA Mensageiro/metabolismo , Neoplasias da Bexiga Urinária/genética
13.
Int J Cancer ; 82(1): 70-6, 1999 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-10360823

RESUMO

We are investigating the hypothesis that cancer progression involves the formation of abnormal cadherin-catenin complexes. The detailed analysis of cadherins and catenins expressed in a panel of 17 human bladder-cancer cell lines revealed that E-cadherin was down-regulated at the mRNA level in 5 cell lines. Interestingly, plakoglobin was also down-regulated at the mRNA level in these 5 cell lines only. Furthermore, a slower migrating form of pp120 was detected in these cell lines and in 2 cell lines with heterogeneous E-cadherin expression. Cloning of the cadherins expressed in the bladder lines revealed that P-cadherin is expressed in the lines expressing E-cadherin and down-regulated at the mRNA level in lines devoid of E-cadherin. N-cadherin was expressed in the 5 lines with reduced E-cadherin expression, in the 2 lines with heterogeneous E-cadherin expression and in 2 other cell lines. Thus, we showed that catenin changes occur in correlation with lack of E-cadherin expression and that N-cadherin becomes predominantly expressed in cells that have lost E-cadherin expression. Our data suggest that co-regulation of the expression of genes encoding different members of the classical cadherins occurs during tumor progression and that expression of some catenins is also coordinated with cadherin expression.


Assuntos
Caderinas/metabolismo , Proteínas do Citoesqueleto/metabolismo , Transativadores , Neoplasias da Bexiga Urinária/metabolismo , Animais , Caderinas/análise , Caderinas/genética , Clonagem Molecular , Proteínas do Citoesqueleto/análise , Desmoplaquinas , Humanos , Camundongos , Células Tumorais Cultivadas , alfa Catenina , beta Catenina , gama Catenina
14.
J Neuropathol Exp Neurol ; 57(11): 1061-9, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9825943

RESUMO

Germline p53 mutations carry an increased risk of development of breast cancer, soft tissue and osteosarcomas, brain tumors, leukemia and adrenocortical carcinomas. Cerebral neoplasms are usually of astrocytic lineage and occur in 40% of affected families. This report presents clinical, neuropathological and molecular genetic data from 2 families in France with an identical p53 germline mutation in codon 248 (CGG->TGG; Arg->Trp) and a clustering of CNS tumors. The youngest patient in each family developed a malignant choroid plexus tumor while several young adults of both kindred succumbed to low-grade astrocytoma, anaplastic astrocytoma or glioblastoma. The only non-neural neoplasm was an adrenocortical carcinoma in a boy aged 4 years who developed an anaplastic choroid plexus papilloma 2 years later. Of 2 previously reported inherited choroid plexus tumors, 1 occurred in a family which also carried a germline mutation in codon 248. It remains to be shown whether this unusual pattern of CNS tumors is due to an organ-specific effect of this particular p53 mutation or whether it reflects the genetic background of the affected families.


Assuntos
Astrocitoma/genética , Carcinoma/genética , Neoplasias do Plexo Corióideo/genética , Mutação em Linhagem Germinativa/genética , Papiloma/genética , Proteína Supressora de Tumor p53/genética , Adulto , Antígenos Transformantes de Poliomavirus/análise , Astrocitoma/patologia , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/virologia , Criança , Pré-Escolar , Neoplasias do Plexo Corióideo/diagnóstico , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Papiloma/diagnóstico , Papiloma/patologia , Linhagem
15.
Int J Cancer ; 79(5): 531-6, 1998 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-9761125

RESUMO

Phenacetin abuse and smoking are established risk factors for transitional cell carcinomas of the urinary tract. In the present study, we analysed exposure and the clinical course of patients who underwent nephrectomy for transitional cell carcinoma of the renal pelvis. PCR-SSCP of archival, paraffin-embedded histological sections followed by direct DNA sequencing revealed that 29 of 89 (33%) renal pelvic carcinomas contained a p53 mutation. Double mutations were found in 4 tumours and triple mutations in 1 tumour. The incidence of p53 mutations was significantly higher in tumours with grades 3 and 4 than in those with grades 1 and 2 and higher in invasive than in non-invasive tumours. Furthermore, patients with carcinomas carrying a p53 mutation showed poorer survival than those without mutation. The type of p53 mutation in renal pelvic carcinomas was similar to that reported for bladder cancer, G:C-->A:T transition mutations being most frequent (45%, 33% of these at CpG sites), followed by G:C-->T:A and G:C-->C:G transversions. The incidence and type of p53 mutation did not differ significantly in patients with a history of phenacetin abuse, smoking or neither of these habits. This was also true for G:C-->T:A transversions (17.5% of mutations), which are considered typical of smoking-induced carcinomas at other sites, e.g., lung, oral cavity and oesophagus. Our results indicate that the frequency and pattern of p53 mutations are similar in transitional cell carcinomas of the bladder and the renal pelvis and do not reflect exposure to phenacetin and/or smoking. The frequency of genetic polymorphism in genes coding for carcinogen-metabolising enzymes (CYP1A1, NAT1, GSTT1 and GSTM1) was also independent of exposure. Although the sample size of our study does not allow definite conclusions, these data are compatible with chronic tissue damage as a causative factor in the evolution of urothelial carcinomas rather than pointing to a direct mutagenic effect of phenacetin and tobacco-specific carcinogens.


Assuntos
Carcinógenos/metabolismo , Genes p53/genética , Neoplasias Renais/etiologia , Neoplasias Renais/genética , Fenacetina/efeitos adversos , Fumar/efeitos adversos , Idoso , Arilamina N-Acetiltransferase/genética , Citocromo P-450 CYP1A1/genética , Feminino , Glutationa Transferase/genética , Humanos , Isoenzimas/genética , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Transtornos Relacionados ao Uso de Substâncias , Taxa de Sobrevida
16.
Int J Cancer ; 74(5): 523-8, 1997 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-9355975

RESUMO

During the progression of many cancers, cell-cell adhesion molecules, e.g., E-cadherin (EC), may be down-regulated. In a number of carcinomas, EC has been described as an independent prognostic variable. We have studied the expression of adhesion molecules participating in cadherin-catenin complexes in renal cell carcinoma (RCC) specimens. Expression of EC, catenins and p120cas protein was examined in frozen tissue of 90 RCC specimens by immunohistochemistry, and these molecules were evaluated for their significance as prognostic markers. Staining was scored as normal (homogeneously positive at cell-cell borders) or abnormal (heterogeneous or absent). A significant correlation between poor survival and decreased expression of alpha-, beta- or gamma-catenin was observed, whereas no association between survival and EC or p120cas expression was seen. Cox's proportional hazard regression analysis showed that in patients with pT1-3N0M0 disease, reduced alpha-catenin expression correlated with poor survival, suggesting that alpha-catenin expression might be an independent prognostic indicator for patients of this group.


Assuntos
Carcinoma de Células Renais/metabolismo , Proteínas do Citoesqueleto/biossíntese , Neoplasias Renais/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Caderinas/metabolismo , Carcinoma de Células Renais/patologia , Cateninas , Adesão Celular/fisiologia , Moléculas de Adesão Celular/metabolismo , Humanos , Imuno-Histoquímica , Neoplasias Renais/patologia , Pessoa de Meia-Idade , Fosfoproteínas/metabolismo , Prognóstico , Modelos de Riscos Proporcionais , alfa Catenina , delta Catenina
17.
Int J Cancer ; 74(4): 374-7, 1997 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-9291424

RESUMO

It is now well documented that E-cadherin expression correlates inversely with tumor grade in various carcinomas including prostate cancer. We also demonstrated a statistically significant correlation between decreased E-cadherin expression and progression-free period in early stage patients treated by radical prostatectomy and decreased survival in patients with advanced stage disease. We now study the relationship between E cadherin and alpha-catenin expression, because in prostate cancer cell lines, mutational inactivation of the alpha-catenin gene can be the cause of the impaired E-cadherin function. Twenty patients treated by radical prostatectomy and 32 advanced stage patients were evaluated immunohistochemically for E-cadherin and alpha-catenin expression. The results were related to tumor grade and disease progression. Four patients in the radical prostatectomy group had aberrant E-cadherin and alpha-catenin expression and showed disease progression. The other 16 patients were free of progression and had normal E-cadherin and alpha-catenin expression. In the advanced stage group, 4 of 13 patients with normal E-cadherin staining showed aberrant alpha-catenin expression and 2 patients (50%) progressed, compared with only 22% progression in patients with both normal E-cadherin and alpha-catenin expression. The other 19 patients with aberrant E-cadherin and alpha-catenin staining had the poorest prognosis. Our results suggest that loss of alpha-catenin expression could be one of the mechanisms responsible for the loss of E-cadherin-mediated cell-cell adhesion in human prostate cancer and might in some cases provide prognostic information.


Assuntos
Caderinas/análise , Proteínas do Citoesqueleto/análise , Neoplasias da Próstata/patologia , Biomarcadores Tumorais , Proteínas do Citoesqueleto/biossíntese , Progressão da Doença , Seguimentos , Humanos , Imuno-Histoquímica , Masculino , Estadiamento de Neoplasias , Prognóstico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/cirurgia , Taxa de Sobrevida , Fatores de Tempo , alfa Catenina
18.
Biochem Biophys Res Commun ; 241(2): 453-8, 1997 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-9425291

RESUMO

Decreased expression of the intercellular adhesion molecule E-cadherin correlates with tumor aggressiveness and invasion capacity of cell lines. The decrease of E-cadherin expression results primarily from reduced mRNA expression. We show here that the activity of a human E-cadherin promoter construct is cell specific and correlates with E-cadherin mRNA expression. This spectrum of activity is conserved by a region as short as 81 bp obtained after 5' deletion. Mutation analysis revealed that two E box elements of this minimal promoter are involved in the silencing of E-cadherin promoter activity occurring in cancer cells. E boxes are mainly known as target sequences for bHLH transcription factors that are involved in the control of tissue differentiation and are antagonised by HLH proteins. However, mutation data and cotransfection experiments using HLH protein expression vectors indicate that bHLH transcription factors are not significantly involved in the E box mediated silencing of this E-cadherin promoter fragment.


Assuntos
Caderinas/genética , Regulação Neoplásica da Expressão Gênica , Regiões Promotoras Genéticas , Sequência de Bases , Caderinas/biossíntese , Células Cultivadas , Análise Mutacional de DNA , Células Epiteliais , Sequências Hélice-Alça-Hélice , Humanos , Dados de Sequência Molecular , Deleção de Sequência , Distribuição Tecidual , Fatores de Transcrição/metabolismo
19.
Int J Cancer ; 68(2): 183-7, 1996 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-8900425

RESUMO

We have studied p16(INK4) mutation (by PCR-SSCP) and deletion (by Southern blotting and/or multiplex PCR) in a series of 47 bilharziasis-associated tumors from Egypt and compared the results with those obtained on a series of 17 established bladder cell lines and non-bilharziasis-associated bladder cancers from the Netherlands. In the cell lines we found 9 homozygous deletions and 1 mutation (59% of p16(INK4) alterations in cell lines), whereas in cases from the Netherlands deletions were found in 4 of 22 samples. No mutations were detected in the 46 samples screened. Interestingly, in bilharziasis-associated bladder cancer, deletions were present in 23 samples and mutations in a further 2 cases (53% of p16(INK4) alteration in bilharziasis-associated bladder cancer). No correlation was found between p16(INK4) alteration and histopathological data. Likewise, the same frequency of alteration was found in tumors with different differentiation patterns (squamous, transitional or adenocarcinoma). Three conclusions can be drawn from our findings: (i) p16(INK4) alterations are more frequent in cell lines than in primary tumors; (ii) in primary bladder tumors (bilharziasis-associated or not), p16(INK4) deletions are much more frequent than p16(INK4) mutations; (iii) p16(INK4) alterations are more frequent in bilharziasis-associated bladder tumors than in other bladder tumors. This high frequency of deletion is not related to a specific histological type but to the specific etiology of these tumors.


Assuntos
Proteínas de Transporte/genética , Deleção de Genes , Mutação Puntual , Esquistossomose/complicações , Neoplasias da Bexiga Urinária/genética , Inibidor p16 de Quinase Dependente de Ciclina , Egito , Humanos , Países Baixos , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Neoplasias da Bexiga Urinária/parasitologia
20.
Cancer Res ; 56(18): 4154-8, 1996 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-8797585

RESUMO

Loss of E-cadherin-mediated adhesion is an important step in the progression of many carcinomas. In model systems, it has been shown that cadherin function requires not only proper E-cadherin expression but also its linkage to the cytoskeleton through catenins. Hence, defects in catenins may cause defective E-cadherin function, and catenins as well as E-cadherin might constitute prognostic indicators. Here, we extend our previous study on E-cadherin in bladder cancer (Cancer Res., 53: 3241-3245, 1993). We have evaluated the expression of E-cadherin-associated cytoplasmic molecules (alpha-, beta-, and gamma-catenins and p120cas) to clarify whether or not the pattern of their expression could provide additional prognostic information beyond that from E-cadherin alone. Forty-eight frozen bladder tumor specimens and 9 samples of normal urothelium were studied by immunohistochemistry. A discrepancy between the E-cadherin and catenin expression pattern was seen in 20.8% of cases. Abnormal expression of each molecule is significantly correlated with tumor grade (P < 0.01) and stage (P < 0.01). Reduced expression of all of the molecules correlates with poor survival (P < 0.01 for each variable). Proportional hazard regression analysis showed that beta-catenin, E-cadherin, and alpha-catenin have strong predictive value, whereas plakoglobin and p120cas have a somewhat lower predictive value. Within patients with invasive tumors, those with a normal staining for either E-cadherin, alpha-catenin, or beta-catenin show a trend toward better survival. However, the difference in survival is significant only for E-cadherin (P < 0.05). Thus, beta-catenin, E-cadherin, and alpha-catenin have similar prognostic values. Therefore, from a practical point of view, the expression of any of these proteins can be of prognostic value for patients with bladder cancer.


Assuntos
Biomarcadores Tumorais/análise , Moléculas de Adesão Celular/análise , Proteínas do Citoesqueleto/análise , Fosfoproteínas/análise , Transativadores , Neoplasias da Bexiga Urinária/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Caderinas/análise , Cateninas , Moléculas de Adesão Celular/biossíntese , Terapia Combinada , Proteínas do Citoesqueleto/biossíntese , Desmoplaquinas , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fosfoproteínas/biossíntese , Prognóstico , Taxa de Sobrevida , Fatores de Tempo , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/cirurgia , alfa Catenina , beta Catenina , gama Catenina , delta Catenina
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