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1.
Clin Cancer Res ; 13(10): 2870-5, 2007 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-17504985

RESUMO

PURPOSE: Hemostatic activation is common in pancreatic cancer and may be linked to angiogenesis and venous thromboembolism. We investigated expression of tissue factor (TF), the prime initiator of coagulation, in noninvasive and invasive pancreatic neoplasia. We correlated TF expression with vascular endothelial growth factor (VEGF) expression, microvessel density, and venous thromboembolism in resected pancreatic cancer. EXPERIMENTAL DESIGN: Tissue cores from a tri-institutional retrospective series of patients were used to build tissue microarrays. TF expression was graded semiquantitatively using immunohistochemistry in normal pancreas (n=10), intraductal papillary mucinous neoplasms (n=70), pancreatic intraepithelial neoplasia (n=40), and resected or metastatic pancreatic adenocarcinomas (n=130). RESULTS: TF expression was observed in a majority of noninvasive and invasive pancreatic neoplasia, including 77% of pancreatic intraepithelial neoplasias, 91% of intraductal papillary mucinous neoplasms, and 89% of pancreatic cancers, but not in normal pancreas. Sixty-six of 122 resected pancreatic cancers (54%) were found to have high TF expression (defined as grade >or=2, the median score). Carcinomas with high TF expression were more likely to also express VEGF (80% versus 27% with low TF expression, P<0.0001) and had a higher median MVD (8 versus 5 per tissue core with low TF expression, P=0.01). Pancreatic cancer patients with high TF expression had a venous thromboembolism rate of 26.3% compared with 4.5% in patients with low TF expression (P=0.04). CONCLUSIONS: TF expression occurs early in pancreatic neoplastic transformation and is associated with VEGF expression, increased microvessel density, and possibly clinical venous thromboembolism in pancreatic cancer. Prospective studies evaluating the role of TF in pancreatic cancer outcomes are warranted.


Assuntos
Neovascularização Patológica/etiologia , Neoplasias Pancreáticas/irrigação sanguínea , Neoplasias Pancreáticas/mortalidade , Tromboplastina/metabolismo , Trombose Venosa/etiologia , Idoso , Capilares , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/química , Análise de Sobrevida , Tromboplastina/análise , Fator A de Crescimento do Endotélio Vascular/metabolismo
2.
J Gastrointest Surg ; 9(7): 903-11, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16137582

RESUMO

Angiogenesis is important for pancreatic cancer progression, but its role in predicting response to therapy is not known. We investigated the association of various angiogenic factors and intratumoral microvessel density (IMD) with adjuvant therapy and survival in resected pancreatic cancer. Tissue cores from a multi-institutional retrospective series of resected patients were used to build a pancreatic cancer tissue microarray. Vascular endothelial growth factor (VEGF), platelet-derived endothelial cell growth factor (PD-ECGF), CD31 (for IMD), and DPC4 expression were determined using immunohistochemistry. Expression of VEGF and PD-ECGF, both proangiogenic factors, was observed in 70 (56%) and 75 (59%) of 124 tumors, respectively. Expression of DPC4, an angiogenesis inhibitor, was observed in 59 of 124 (48%) tumors. VEGF expression correlated significantly with increased IMD (P=.03), as did loss of antiangiogenic DPC4 (P=.05). PD-ECGF expression did not correlate with IMD. Use of adjuvant therapy was associated with increased survival in patients with VEGF-positive tumors (18.8 [treated] versus 11.2 [untreated] months; hazard ratio [HR]=0.38, 95% confidence interval [CI], 0.19-0.76; P=.005), but not in patients with VEGF-negative tumors. Similarly, improved survival was observed in patients with high IMD (16.3 [treated] versus 11.2 [untreated] months; HR=0.44, 95% CI, 0.23-0.87; P=.02) and in patients with loss of DPC4 (20.3 [treated] versus 11.2 [untreated] months; HR=0.31, 95% CI, 0.14-0.67; P=.002), but not in those with low IMD or normal DPC4 expression. VEGF (stimulator) and DPC4 (inhibitor) are important regulators of pancreatic tumor angiogenesis and predictive of benefit from adjuvant therapy. Adjuvant therapy may have both antiangiogenic and cytotoxic effects. Addition of anti-VEGF agents to adjuvant regimens may further improve outcomes.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias Pancreáticas/cirurgia , Proteína Smad4/análise , Fator A de Crescimento do Endotélio Vascular/análise , Fatores Etários , Idoso , Indutores da Angiogênese/análise , Inibidores da Angiogênese/análise , Quimioterapia Adjuvante , Feminino , Previsões , Humanos , Masculino , Microcirculação/ultraestrutura , Neoplasias Pancreáticas/irrigação sanguínea , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Radioterapia Adjuvante , Estudos Retrospectivos , Fatores Sexuais , Análise de Sobrevida , Timidina Fosforilase/análise , Resultado do Tratamento
3.
Int J Cancer ; 114(3): 387-93, 2005 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-15551330

RESUMO

Human 8-oxoguanine DNA glycosylase 1 (hOGG1) plays a major role in the repair of 8-hydroxyguanine, one of the major forms of DNA damage generated by reactive oxygen species in tobacco smoke. If left unrepaired by hOGG1, 8-hydroxyguanine can produce G:C-to-T:A transversions. Recent studies have suggested that the hOGG1 Ser326Cys polymorphism is associated with both a decrease in enzyme activity and an increased risk of lung cancer. To define the interaction between tobacco carcinogens, hOGG1-mediated DNA repair and DNA damage, we examined the role of the hOGG1 Ser326Cys polymorphism in mutation of the p53 gene in non small cell lung cancer (NSCLC). Tumor and nonneoplastic DNA were collected from 141 cigarette smokers with NSCLC. p53 mutations were detected by direct dideoxy sequencing and/or the GeneChip p53 assay in 74 of the 141 (52%) tumors. hOGG1 codon 326 polymorphisms were identified by polymerase chain reaction-restriction fragment length polymorphism analysis. The distribution of hOGG1 codon 326 genotypes was Ser/Ser, 90 of 141 (64%); Ser/Cys, 45 of 141 (32%); and Cys/Cys, 6 of 141 (4%). p53 mutations were significantly (p = 0.04) less common in NSCLC from patients with codon 326 Ser/Cys or Cys/Cys genotypes (21 of 51; 41%) than in NSCLC from Ser/Ser homozygotes (53 of 90; 59%). The decrease in p53 mutation frequency among carriers of the Cys allele was more evident in lung squamous cell cancer [7 of 17 (41%) for Cys/Cys and Ser/Cys vs. 27 of 38 (71%) for Ser/Ser; p = 0.04] than in nonbronchoalveolar adenocarcinoma [11 of 26 (42%) for Cys/Cys and Ser/Cys vs. 20 of 35 (57%) for Ser/Ser; p = 0.25]. The prevalence of G:C-to-T:A transversions was similar among hOGG1 codon 326 genotypes. In summary, the hOGG1 codon 326 Cys allele was associated with a decrease in p53 mutations and no effect on G:C-to-T:A transversions in NSCLC. This decrease in p53 mutations in vivo is not consistent with a decrease in the repair of 8-hydroxyguanine among carriers of the hOGG1 codon 326 Cys allele in vitro.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , DNA Glicosilases/genética , Genes p53/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/fisiopatologia , Polimorfismo Genético , Fumar/efeitos adversos , Idoso , Códon , Dano ao DNA , DNA Glicosilases/farmacologia , Reparo do DNA , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Mutação Puntual
4.
Clin Cancer Res ; 9(11): 4165-71, 2003 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-14519641

RESUMO

PURPOSE: Thymidylate synthase (TS) is the target enzyme for 5-fluorouracil (5-FU), and TS expression may determine clinical response and survival after therapy with 5-FU in colorectal cancer. 5-FU is also widely used in the adjuvant therapy of pancreatic cancer. Therefore, we explored the hypothesis that TS expression was associated with patient prognosis and the response to adjuvant therapy in pancreatic cancer. EXPERIMENTAL DESIGN: Cylindrical tissue cores from a large retrospective, nonrandomized series covering 132 resected patients were used to build a pancreatic cancer tissue microarray. TS expression was determined using immunohistochemistry. RESULTS: High intratumoral TS expression and low intratumoral TS expression were present in 83 of 132 (63%) and 49 of 132 (37%) tumors, respectively. Median survival among patients with low intratumoral TS expression (18 months) was longer than that among patients with high TS expression (12 months). In multivariate analysis, more advanced pathological stage [risk ratio (RR) = 1.70; P = 0.015], poorly differentiated histology (RR = 1.71; P = 0.015), management with adjuvant therapy (RR = 0.49; P = 0.011), and high TS expression [RR = 1.66; 95% confidence interval (CI) = 1.05-2.63; P = 0.029] were independent predictors of mortality. The risk of death was significantly reduced by any adjuvant therapy (RR = 0.40; 95% CI = 0.18-0.90; P = 0.001) among patients with high TS expression. This difference in survival among patients with low- and high-TS-expressing tumors became more significant when the analysis was restricted to the 73 patients receiving 5-FU-based adjuvant therapy (RR = 0.37; 95% CI = 0.16-0.86; P = 0.0006). In contrast, 5-FU-based adjuvant therapy did not influence survival among patients with low-TS-expressing pancreatic cancer. CONCLUSIONS: High TS expression is a marker of poor prognosis in resected pancreatic cancer. Patients with high intratumoral TS expression benefit from adjuvant therapy.


Assuntos
Adenocarcinoma/genética , Antimetabólitos Antineoplásicos/uso terapêutico , Fluoruracila/uso terapêutico , Neoplasias Pancreáticas/genética , Timidilato Sintase/genética , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Idoso , Quimioterapia Adjuvante , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Prognóstico , Estudos Retrospectivos
5.
World J Gastroenterol ; 9(10): 2202-6, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14562378

RESUMO

AIM: To describe the correlation between immunostaining patterns of p16 and CDK4 and prognosis in colorectal carcinoma. METHODS: Paraffin sections of 74 cases of colorectal carcinoma were analysed immunohistochemically for expression of p16 and CDK4 proteins. RESULTS: Most carcinomas showed stronger p16 and CDK4 immunostaining in the cytoplasm than the adenomas or the adjacent normal mucosa. Strong immunostaining of p16 was a predictor for better prognosis whereas strong cytoplasmic immunostaining of CDK4 was a predictor for poor prognosis. Both p16 and CDK4 immunostainings were correlated with histological grade or Dukes' stage. CONCLUSION: These results support the experimental evidence that interaction of expression of p16 and CDK4 may play an important role in the Rb/p16 pathway, and the expression patterns of CDK4 and p16 may be imperative in the development of colorectal carcinoma, thus becoming a new prognostic marker in colorectal cancer.


Assuntos
Adenoma/mortalidade , Adenoma/patologia , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Quinases Ciclina-Dependentes/genética , Proteínas Proto-Oncogênicas , Adenoma/fisiopatologia , Biomarcadores Tumorais , Neoplasias Colorretais/fisiopatologia , Quinase 4 Dependente de Ciclina , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Valor Preditivo dos Testes , Prognóstico , Regiões Promotoras Genéticas , RNA Mensageiro/análise , Taxa de Sobrevida
6.
Mutat Res ; 528(1-2): 19-27, 2003 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-12873719

RESUMO

The X-ray repair cross-complementing group 1 (XRCC1) gene plays a critical role in the repair of DNA single-strand breaks. A polymorphism at codon 399 of the XRCC1 gene (Arg to Gln) is associated with increased DNA adduct binding and an increase in sister chromatid exchanges after exposure to tobacco carcinogens and may be linked with an increased risk of lung cancer. To further define the interaction between tobacco carcinogens, XRCC1-mediated DNA repair and DNA damage, we examined the role of the XRCC1 codon 399 polymorphism in mutation of the p53 gene in non-small cell lung cancer (NSCLC). Tumor and non-neoplastic (lung or lymphocyte) samples were collected from 116 cigarette smokers with NSCLC. p53 mutations were detected by direct sequencing and/or the GeneChip p53 assay in 63 of 116 (54%) tumors. XRCC1 polymorphisms were identified by PCR/RFLP analysis. The distribution of XRCC1 codon 399 genotypes was (Arg/Arg [74 of 116, 64%], Arg/Gln [29 of 116, 25%], and Gln/Gln [13 of 116, 11%]). The prevalence of p53 mutations was similar among subjects with all three XRCC1 genotypes (Arg/Arg [39 of 74, 53%], Arg/Gln [18 of 29, 62%], and Gln/Gln [6 of 13, 46%]). However, the prevalence of specific p53 mutations varied among different XRCC1 genotypes. AT to GC transitions were significantly (P=0.01) more common among subjects with the Gln/Arg or Gln/Gln genotype (5 of 42, 12%) than in subjects with the Arg/Arg genotype (1 of 74, 1.4%). In summary, the XRCC1 Gln allele is associated with AT to GC mutations in p53 in NSCLC. The XRCC1 gene may play a role in the repair of cigarette smoking-induced DNA damage.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Proteínas de Ligação a DNA , Genes p53 , Neoplasias Pulmonares/genética , Polimorfismo Genético , Adenina , Alelos , Feminino , Genótipo , Guanina , Humanos , Masculino , Mutação Puntual , Fumar/efeitos adversos , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
7.
Oncogene ; 21(48): 7289-97, 2002 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-12379873

RESUMO

Smoking is directly responsible for approximately 90% of lung cancers and is also strongly associated with cancers of the head and neck, esophagus and urinary bladder. Our growing understanding of the molecular changes that underlie cancer progression has contributed to the development of novel molecular approaches for the detection of cancer. In this study, we review a number of recent studies that have used molecular techniques to detect neoplastic DNA from lung, head and neck, esophagus and bladder cancer. The majority of these approaches are based on polymerase chain reaction (PCR) based assays. These PCR-based techniques can detect a few clonal cancer cells containing a specific DNA mutation, microsatellite alteration, or CpG island methylation among an excess background of normal cells. The ability to accurately detect a small number of malignant cells in a wide range of clinical specimens including sputum, saliva, bronchoalveolar lavage fluid, urine, serum, plasma, or tissue has significant implications for screening high-risk individuals (such as cigarette smokers) for cancer.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Neoplasias Esofágicas/diagnóstico , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias Pulmonares/diagnóstico , Fumar/efeitos adversos , Neoplasias da Bexiga Urinária/diagnóstico , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/etiologia , Neoplasias Esofágicas/genética , Neoplasias de Cabeça e Pescoço/etiologia , Neoplasias de Cabeça e Pescoço/genética , Humanos , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/genética , Neoplasias da Bexiga Urinária/etiologia , Neoplasias da Bexiga Urinária/genética
8.
Cancer Genet Cytogenet ; 135(2): 120-7, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12127396

RESUMO

The establishment of esophageal cancer cell lines can facilitate the search for molecular mechanisms underlying its pathogenesis. Two novel human esophageal squamous cell carcinoma (ESCC) cell lines, HKESC-2 and HKESC-3, were established from a moderately differentiated ESCC of a 46-year-old Chinese woman and a well-differentiated ESCC of a 74-year-old Chinese man, both from Hong Kong. The pathological characteristics (morphological, immunohistochemical, and electron microscopic studies), tumorigenicity in nude mice, cytogenetic features, and DNA ploidy of the two cell lines were investigated. The two cell lines have been maintained in vitro for more than 17 months and passaged over 85 times for HKESC-2 and 58 times for HKESC-3. Both grew as monolayers, with a doubling time of 24 hours for HKESC-2 and 48 h for HKESC-3. Their squamous epithelial nature was authenticated by their strong immunopositivity with the anti-cytokeratin antibodies and the ultrastructural demonstration of tonofilaments and desmosomes. They are tumorigenic in nude mice and had DNA aneuploidy. G-banding cytogenetic analysis showed hyperdiploidy in HKESC-2 and near-tetraploidy in HKESC-3. Frequent breakpoints were noted at 1p22, 1p32, and 9q34 in HKESC-2 and at 1p31, 3p25, 3p14, 6q16, 6q21, 8p21, 9q34, 13q32, and 17q25 in HKESC-3. Comparative genomic hybridization analysis found that chromosomal gains were at 3q24-qter, 5q21-qter, 8q11-qter, 13q21-q31, 17q11-qter, 19, 22q22 for HKESC-2 and at 3q13-qter, 5p, 6p, 9q21-qter, 10q21-q22, 12q15-pter, 14q24-qter, 16, 17q24-qter, 20 for HKESC-3. Chromosomal losses were at 3p13-pter, 18q12-qter for HKESC-3. These two newly established cell lines will be useful tools in the study of the molecular pathogenesis and biological behavior of ESCC cells and for testing new therapeutic reagents for ESCC in the future.


Assuntos
Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , Células Tumorais Cultivadas , Idoso , Aneuploidia , Animais , Povo Asiático , Carcinoma de Células Escamosas/genética , Divisão Celular , Cromossomos Humanos/ultraestrutura , Neoplasias Esofágicas/genética , Feminino , Hong Kong , Humanos , Cariotipagem , Queratinas/análise , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Proteínas de Neoplasias/análise , Transplante de Neoplasias , Hibridização de Ácido Nucleico , Transplante Heterólogo , Células Tumorais Cultivadas/química , Células Tumorais Cultivadas/patologia
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