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1.
Diagn Mol Pathol ; 12(4): 224-30, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14639108

RESUMO

The diagnosis of small round cell sarcomas is often very difficult, especially when only small biopsy specimens are available for examination. Recent studies have shown that some sarcomas have specific recurrent chromosomal translocations producing chimeric gene fusions, which can be detected by reverse transcription-polymerase chain reaction (RT-PCR), fluorescent in situ hybridization (FISH), or cytogenetic analysis. In this study, 12 cases of well-defined sarcomas including Ewings sarcoma/primitive neuroectodermal tumors (ES/PNET), synovial sarcoma (SS), alveolar rhabdomyosarcoma (ARMS), and desmoplastic small round cell tumors (DSRCT) were used to collect specific numbers of cells by laser capture microdissection (LCM), subsequently used for RT-PCR to detect specific chimeric gene transcripts. Tumor cells from fresh-frozen (FS) tissue sections and paraffin-embedded (PS) tissue sections from the same cases were compared directly to evaluate the sensitivity of FS and PS sections as the starting material for analysis. Samples were used for RNA extraction, RT-PCR analysis, and Southern hybridization with fluorescein-labeled internal probes followed by enhance chemiluminescence (ECL) detection. The fusion gene transcripts could be detected using 50 cells from FS materials in all cases and from 1 cell in 9 of 12 cases. For PS, a positive signal could be detected using 200 to 1000 cells in all cases, while weaker signals were detected using 50 cells in most cases. These results indicate that the fusion gene products from small round cell sarcomas can be detected by RT-PCR with 10 to 200 cells from FS and PS tissues. The sensitivity of RT-PCR with FS was 10- to 50-fold greater than with PS. These results also suggest that RT-PCR analysis for sarcoma fusion gene products can be successfully performed when only a few cells are available for analysis, although this is not recommended for routine clinical use.


Assuntos
Proteínas de Fusão Oncogênica/genética , Sarcoma/genética , Neoplasias de Tecidos Moles/genética , Translocação Genética , Southern Blotting , Primers do DNA/química , Sondas de DNA/química , Humanos , Lasers , Microdissecção , Inclusão em Parafina , RNA Mensageiro/metabolismo , RNA Neoplásico/análise , RNA Neoplásico/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sarcoma/metabolismo , Sarcoma/patologia , Sensibilidade e Especificidade , Análise de Sequência de DNA , Neoplasias de Tecidos Moles/metabolismo , Neoplasias de Tecidos Moles/patologia , Fixação de Tecidos
2.
Oncogene ; 22(24): 3813-20, 2003 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-12802289

RESUMO

Chronic infections with the hepatitis B virus (HBV) and high-risk human papillomaviruses (HPVs) are important risk factors for hepatocellular carcinoma (HCC) and cervical cancer (CC), respectively. HBV and HPV are DNA viruses that almost invariably integrate into the host genome in invasive tumors. The viral integration sites occur throughout the genome, leading to the presumption that there are no preferred sites of integration. A number of viral integrations have been shown to occur within the vicinity of important cancer-related genes. In studies of HBV-induced HCC and HPV-induced CC, we have identified two HBV and three HPV integrations into the human telomerase reverse transcriptase (hTERT) gene. Detailed characterization of the integrations revealed that four integrations occurred within the hTERT promoter and upstream region and the fifth integration occurred in intron 3 of the hTERT gene. None of the integrations altered the hTERT coding sequence and all resulted in juxtaposition of viral enhancers near hTERT, with potential activation of hTERT expression. Our work supports the hypothesis that the sites of oncogenic viral integration are nonrandom and that genes at the sites of viral integration may play important roles in carcinogenesis.


Assuntos
Vírus da Hepatite B/genética , Neoplasias Hepáticas/virologia , Papillomaviridae/genética , Telomerase/genética , Neoplasias do Colo do Útero/virologia , Integração Viral , Sequência de Bases , Proteínas de Ligação a DNA , Feminino , Regulação Enzimológica da Expressão Gênica , Humanos , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/etiologia , Dados de Sequência Molecular , Células Tumorais Cultivadas , Neoplasias do Colo do Útero/enzimologia , Neoplasias do Colo do Útero/etiologia
3.
Gut ; 51(4): 496-501, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12235070

RESUMO

BACKGROUND: Interstitial cells of Cajal (ICC) are required for normal intestinal motility. ICC are found throughout the human colon and are decreased in the sigmoid colon of patients with slow transit constipation. AIMS: The aims of this study were to determine the normal distribution of ICC within the human colon and to determine if ICC are decreased throughout the colon in slow transit constipation. PATIENTS: The caecum, ascending, transverse, and sigmoid colons from six patients with slow transit constipation and colonic tissue from patients with resected colon cancer were used for this study. METHODS: ICC cells were identified with a polyclonal antibody to c-Kit, serial 0.5 microm sections were obtained by confocal microscopy, and three dimensional software was employed to reconstruct the entire thickness of the colonic muscularis propria and submucosa. RESULTS: ICC were located within both the longitudinal and circular muscle layers. Two networks of ICC were identified, one in the myenteric plexus region and another, less defined network, in the submucosal border. Caecum, ascending colon, transverse colon, and sigmoid colon displayed similar ICC volumes. ICC volume was significantly lower in the slow transit constipation patients across all colonic regions. CONCLUSIONS: The data suggest that ICC distribution is relatively uniform throughout the human colon and that decreased ICC volume is pan-colonic in idiopathic slow transit constipation.


Assuntos
Colo/patologia , Constipação Intestinal/fisiopatologia , Motilidade Gastrointestinal/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ceco/patologia , Ceco/fisiopatologia , Colo/fisiopatologia , Constipação Intestinal/patologia , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Microscopia Confocal , Pessoa de Meia-Idade
4.
J Vasc Interv Radiol ; 12(12): 1437-9, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11742021

RESUMO

A technique was developed to perform endoluminal biliary biopsy with use of a commercially available 19-g gun. In 18 patients, a biopsy set consisting of an outer 7-F, 50-cm sheath, an inner curved 14-g metal cannula, and a 60-cm, 19-g biopsy gun with a 20-mm throw was employed to obtain tissue from suspicious-appearing biliary strictures via preexisting transhepatic tracts. The endoluminal biopsy was positive for neoplasm in 13 of 18 cases with three false negatives, one true negative, and one patient with insufficient follow-up. One biopsy was complicated by a hepatic artery pseudoaneurysm, which was successfully treated with coil embolization.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico , Biópsia/instrumentação , Biópsia/métodos , Adulto , Idoso , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Feminino , Humanos , Masculino , Radiografia Intervencionista
5.
Am J Hum Genet ; 69(4): 780-90, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11524701

RESUMO

A comprehensive analysis of somatic and germline mutations related to DNA mismatch-repair (MMR) genes can clarify the prevalence and mechanism of inactivation in colorectal carcinoma (CRC). In the present study, 257 unselected patients referred for CRC resection were examined for evidence of defective DNA MMR. In particular, we sought to determine the frequency of hereditary defects in DNA MMR in this cohort of patients. MMR status was assessed by testing of tumors for the presence or absence of hMLH1, hMSH2, and hMSH6 protein expression and for microsatellite instability (MSI). Of the 257 patients, 51 (20%) had evidence of defective MMR, demonstrating high levels of MSI (MSI-H) and an absence of either hMLH1 (n=48) or hMSH2 (n=3). All three patients lacking hMSH2, as well as one patient lacking hMLH1, also demonstrated an absence of hMSH6. DNA sequence analysis of the 51 patients with defective MMR revealed seven germline mutations-four in hMLH1 (two truncating and two missense) and three in hMSH2 (all truncating). A detailed family history was available for 225 of the 257 patients. Of the seven patients with germline mutations, only three had family histories consistent with hereditary nonpolyposis colorectal cancer. Of the remaining patients who had tumors with defective MMR, eight had somatic mutations in hMLH1. In addition, hypermethylation of the hMLH1 gene promoter was present in 37 (88%) of the 42 hMLH1-negative cases available for study and in all MSI-H tumors that showed loss of hMLH1 expression but no detectable hMLH1 mutations. Our results suggest that, although defective DNA MMR occurs in approximately 20% of unselected patients presenting for CRC resection, hereditary CRC due to mutations in the MMR pathway account for only a small proportion of patients. Of the 257 patients, only 5 (1.9%) appear to have unequivocal evidence of hereditary defects in MMR. The epigenetic (nonhereditary) mechanism of hMLH1 promoter hypermethylation appears to be responsible for the majority of the remaining patients whose tumors are characterized by defective DNA MMR.


Assuntos
Pareamento Incorreto de Bases/genética , Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo do DNA/genética , Predisposição Genética para Doença/genética , Mutação em Linhagem Germinativa/genética , Mutação/genética , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Proteínas de Transporte , Neoplasias Colorretais Hereditárias sem Polipose/epidemiologia , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Metilação de DNA , Análise Mutacional de DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Éxons/genética , Feminino , Humanos , Íntrons/genética , Masculino , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo
6.
Int J Oncol ; 19(3): 567-70, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11494037

RESUMO

The role of microsatellite instability (MSI) in the pathogenesis of hepatocellular carcinoma (HCC) is incompletely defined. Although high-frequency MSI (MSI-H) is infrequently seen in HCC, some studies have suggested a role for MSI in HCC development. While MSI has been clearly defined for a subset of tumors, in particular colorectal, gastric and endometrial cancers, generally accepted criteria have not been developed for other tumors. Colorectal cancers (CRC) are classified as MSI-H if >30-40% of >5 microsatellite loci analyzed show instability. The MSI-H phenotype is associated with defective DNA mismatch repair (MMR) and is observed in the majority of tumors from patients with hereditary non-polyposis colon cancer (HNPCC) and also in 15% of sporadic CRCs. Inactivating mutations of the hMLH1 or hMSH2 genes lead to defects in MMR in HNPCC. In sporadic CRCs, MMR is usually due to hypermethylation of the hMLH-1 promoter. The role of defective MMR in hepatocellular carcinogenesis is controversial. Immunohistochemistry for hMLH1 and hMSH2 reliably indicates hMLH1 or hMSH2 loss in MSI-H CRC tumors. To investigate the role of defective MMR in HCC carcinogenesis, we performed immunohistochemistry for hMLH1 and hMSH2 on 36 HCCs. BAT26, a microsatellite marker that reliably predicts MSI-H was also examined. All 36 of the tumors stained positively for both hMLH1 and hMSH2, strongly suggesting an absence of either inactivating mutations of hMLH1 and hMSH2 or promoter hypermethylation of hMLH1. None of the tumors showed MSI at the BAT26 locus. These findings suggest that defective MMR does not contribute significantly to hepatocellular carcinogenesis.


Assuntos
Pareamento Incorreto de Bases , Carcinoma Hepatocelular/metabolismo , Proteínas de Ligação a DNA , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/genética , Proteínas de Transporte , Metilação de DNA , Primers do DNA/química , Feminino , Humanos , Técnicas Imunoenzimáticas , Neoplasias Hepáticas/genética , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS , Proteínas de Neoplasias/genética , Estadiamento de Neoplasias , Proteínas Nucleares , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas/genética
7.
Cancer ; 92(1): 181-7, 2001 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-11443625

RESUMO

BACKGROUND: The CDH1 gene encodes E-cadherin, an epithelial cell adhesion molecule. Germline CDH1 mutations recently were identified in families with hereditary diffuse gastric carcinoma in a pattern suggestive of autosomal dominant inheritance with incomplete penetrance. METHODS: The proband was a woman age 47 years with a strong family history of diffuse gastric carcinoma. A germline E-cadherin gene mutation was identified in this patient, her brother, and three first cousins. All five family members underwent endoscopic evaluations, which were negative for malignancy, and elected to undergo a prophylactic total gastrectomy with Roux-en-Y esophagojejunostomy. RESULTS: Pathologic examination of the proband's stomach revealed several microscopic foci of intramucosal signet ring cell adenocarcinoma in the cardia and proximal gastric body. Postgastrectomy specimens from the proband's brother and three first cousins all showed intramucosal signet ring cell adenocarcinoma in various regions of the stomach. Immunoperoxidase studies performed on gastric tissue from these five patients demonstrated diminished or absent E-cadherin reactivity in the cancerous mucosa. CONCLUSIONS: Although total gastrectomy was performed as a prophylactic intervention, occult gastric carcinoma was discovered in all five patients. Thus, total gastrectomy should be curative for gastric carcinoma in these patients. Based on their successful outcomes and the lack of efficacious surveillance methods for diffuse gastric carcinoma, prophylactic total gastrectomy may be the management of choice for germline E-cadherin gene mutation carriers. However, prophylactic total gastrectomy should be undertaken cautiously because the procedure may be associated with considerable morbidity.


Assuntos
Caderinas/genética , Mutação em Linhagem Germinativa , Neoplasias Gástricas/genética , Adulto , Feminino , Gastrectomia , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Prevenção Primária , Neoplasias Gástricas/patologia , Neoplasias Gástricas/prevenção & controle
8.
Gastroenterology ; 120(7): 1630-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11375945

RESUMO

BACKGROUND & AIMS: The identification of any high-grade dysplasia (HGD) in Barrett's esophagus has been considered to be an indication for esophagectomy because of the increased risk of cancer. The aim of this study was to determine if a limited extent of HGD has the same potential for cancer as diffuse HGD. METHODS: A retrospective cohort study was performed to assess the risk of developing adenocarcinoma in relationship to the extent of HGD found on endoscopic surveillance. The extent of HGD was defined as focal if cytologic and/or architectural changes of HGD were limited to a single focus of 5 or fewer crypts and diffuse if more than 5 crypts were involved in a single biopsy specimen or if HGD involved more than one biopsy fragment. The relative risk of cancer was assessed using a Cox proportional hazard model, and cancer-free survival was determined using survival curves. RESULTS: Sixty-seven patients with diffuse HGD and 33 with focal HGD satisfied selection criteria. Cancer-free survival rates at 1 and 3 years were 93% and 86% for focal HGD compared with 62% and 44% for diffuse HGD (P < 0.001). On univariate analysis, extent of HGD (relative risk, 5.36; 95% confidence interval, 1.84-15.56), nodularity on endoscopy (relative risk, 3.98; 95% confidence interval, 1.97-8.04), and lack of acid suppression (relative risk, 2.48; 95% confidence interval, 1.16-5.28) were associated with an increased risk of esophageal adenocarcinoma. Diffuse HGD had a 3.7-fold increase in the risk of esophageal cancer compared with focal HGD (P = 0.02) on multivariate analysis. CONCLUSIONS: Patients with focal HGD are less likely to have cancer during the first year after diagnosis or on subsequent follow-up compared with diffuse HGD.


Assuntos
Adenocarcinoma/etiologia , Esôfago de Barrett/patologia , Neoplasias Esofágicas/etiologia , Esôfago/patologia , Adulto , Idoso , Esôfago de Barrett/complicações , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Risco
9.
Am J Gastroenterol ; 96(5): 1522-8, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11374693

RESUMO

OBJECTIVE: Eosinophils infiltrate the colonic mucosa of patients with collagenous colitis (CC), although the pathogenetic implications are unknown, including whether these eosinophils are activated and degranulate in situ. We examined eosinophil infiltration and degranulation in the intestines of patients with CC by immunofluorescence for eosinophil granule major basic protein (MBP). METHODS: We used both conventional histology (hematoxylin and eosin) and indirect MBP immunofluorescence histochemistry on colon biopsy specimens from patients with CC (n = 21) and from healthy controls (n = 9). Scoring of histological features was performed on hematoxylin and eosin-stained sections on a 0 to 3 scale. Eosinophil infiltration and degranulation, as quantified by extracellular MBP staining, were scored in each specimen on a 0 to 4 scale. RESULTS: The inflammatory infiltrate of the lamina propria, the thickness of the collagen band, the numbers of intraepithelial lymphocytes, and degree of epithelial cell damage were all significantly increased in patients with CC as compared to controls (p < 0.0001). Scores for both eosinophil infiltration and degranulation were also significantly higher in the CC group compared to controls (p < 0.0001). The degree of infiltrating eosinophils by hematoxylin and eosin was correlated with eosinophil infiltration and degranulation by MBP immunostaining; however, no other correlations were found between eosinophil infiltration or degranulation by immunofluorescence and any of the histological parameters measured in the CC group. CONCLUSIONS: Eosinophil infiltration and degranulation are increased in the colonic mucosa of patients with CC compared to healthy controls. Eosinophils and their cytotoxic granule proteins could be involved in the pathogenesis of CC. Further studies will be necessary to elucidate the mechanisms of eosinophil activation in CC.


Assuntos
Degranulação Celular , Colite/patologia , Colite/fisiopatologia , Colágeno/metabolismo , Eosinófilos/patologia , Eosinófilos/fisiologia , Ribonucleases , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas Sanguíneas/metabolismo , Colo/patologia , Colo/fisiopatologia , Proteínas Granulares de Eosinófilos , Feminino , Imunofluorescência , Humanos , Mucosa Intestinal/patologia , Mucosa Intestinal/fisiopatologia , Masculino , Pessoa de Meia-Idade
10.
J Hepatol ; 34(2): 248-53, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11281553

RESUMO

BACKGROUND/AIMS: The pathogenesis of alcoholic hepatitis (AH) remains poorly understood. Although apoptosis is now recognized as a mechanism of liver injury, the extent and mechanisms of apoptosis in human AH remain unknown. Thus, our aims were to quantify hepatocyte apoptosis in patients with AH, correlate it with disease severity, and identify the mechanisms of apoptosis induction. METHODS: Hepatocyte apoptosis was assessed in 26 patients with AH and 27 controls without liver disease using the TUNEL assay and immunohistochemistry for activated caspase 3. Liver specimens were also graded for disease severity. The expression of the death receptors, Fas and tumor necrosis factor-alpha receptor 1 (TNF-R1), was assessed by immunohistochemistry. RESULTS: In contrast to normal livers, TUNEL- and caspase 3-positive hepatocytes were readily observed in the livers of patients with AH. In the AH group, hepatocyte apoptosis was significantly higher in patients with a serum bilirubin of > 3 mg/dl. Apoptosis was also greater in grade 4 steatohepatitis. The Fas receptor was strongly expressed in hepatocytes in AH, but not in normal livers; the TNF-R1 expression was comparable in both groups. CONCLUSIONS: The present results demonstrate that hepatocyte apoptosis is significantly increased in human AH and justify therapeutic strategies aimed at inhibiting apoptosis in this disease.


Assuntos
Apoptose , Hepatite Alcoólica/patologia , Hepatócitos/patologia , Antígenos CD/metabolismo , Estudos de Casos e Controles , Caspase 3 , Caspases/metabolismo , Hepatite Alcoólica/etiologia , Hepatite Alcoólica/fisiopatologia , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Modelos Biológicos , Receptores do Fator de Necrose Tumoral/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral , Regulação para Cima , Receptor fas/metabolismo
11.
Mayo Clin Proc ; 76(2): 217-25, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11213314

RESUMO

Endoscopy plays an important role in the identification, diagnosis, and treatment of Barrett esophagus. Short-segment (<2-3 cm) and traditional long-segment (>2-3 cm) Barrett esophagus are distinguished solely on the length of metaplastic tissue above the esophagogastric junction. The histologic hallmark of intestinal metaplasia is required to confirm diagnosis. Biopsy specimens obtained from tissue of presumed Barrett esophagus or an irregular Z line confirm metaplastic glandular mucosa and permit evaluation of dysplastic or neoplastic changes. In the appropriate clinical setting, the use of adjunctive diagnostic techniques may facilitate the diagnosis of Barrett esophagus and sequelae such as dysplasia. Chromoendoscopy with high-resolution or magnified endoscopy is simple, safe, and desirable for surveillance but requires additional procedural time. The use of light-induced fluorescence endoscopy and light-scattering spectroscopy (i.e., optical biopsy) is appealing for the diagnosis and characterization of suspicious lesions. Adjunctive endoscopic techniques and adherence to a protocol for performing biopsies facilitate the early detection and subsequent surveillance of Barrett esophagus.


Assuntos
Esôfago de Barrett/diagnóstico , Esofagoscopia , Esôfago de Barrett/patologia , Esôfago de Barrett/terapia , Biópsia , Humanos , Azul de Metileno , Sensibilidade e Especificidade
12.
Gut ; 48(3): 304-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11171817

RESUMO

BACKGROUND: The incidence of oesophageal adenocarcinoma has increased greatly. Barrett's oesophagus is a known risk factor. AIMS: To identify changes in the incidence, prevalence, and outcome of Barrett's oesophagus in a defined population. SUBJECTS: Residents of Olmsted County, Minnesota, with clinically diagnosed Barrett's oesophagus, or oesophageal or oesophagogastric junction adenocarcinoma. METHODS: Cases were identified using the Rochester Epidemiology Project medical records linkage system. Records were reviewed with follow up to 1 January 1998. RESULTS: The incidence of clinically diagnosed Barrett's oesophagus (>3 cm) increased 28-fold from 0.37/100 000 person years in 1965-69 to 10.5/100 000 in 1995-97. Of note, gastroscopic examinations increased 22-fold in this same time period. The prevalence of diagnosed Barrett's oesophagus increased from 22.6 (95% confidence interval (CI) 11.7-33.6) per 100 000 in 1987 to 82.6/100 000 in 1998. The prevalence of short segment Barrett's oesophagus (<3 cm) in 1998 was 33.4/ 100 000. Patients with Barrett's oesophagus had shorter than expected survival but only one patient with Barrett's oesophagus died from adenocarcinoma. Only four of 64 adenocarcinomas occurred in patients with previously known Barrett's oesophagus. CONCLUSIONS: The incidence and prevalence of clinically diagnosed Barrett's oesophagus have increased in parallel with the increased use of endoscopy. We infer that the true population prevalence of Barrett's oesophagus has not changed greatly, although the incidence of oesophageal adenocarcinoma increased 10-fold. Many adenocarcinomas occurred in patients without a previous diagnosis of Barrett's oesophagus, suggesting that many people with this condition remain undiagnosed in the community.


Assuntos
Adenocarcinoma/epidemiologia , Esôfago de Barrett/epidemiologia , Neoplasias Esofágicas/epidemiologia , Adenocarcinoma/etiologia , Idoso , Esôfago de Barrett/complicações , Intervalos de Confiança , Neoplasias Esofágicas/etiologia , Feminino , Humanos , Incidência , Masculino , Registro Médico Coordenado , Pessoa de Meia-Idade , Minnesota/epidemiologia , Distribuição de Poisson , Prevalência , Prognóstico , Fatores de Risco , Análise de Sobrevida
13.
Genes Chromosomes Cancer ; 30(2): 181-6, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11135435

RESUMO

Twenty percent of colorectal cancers (CRCs) arise in people who have a family history of CRC in at least one other relative. Although a fraction of these CRCs are explained by two well-described autosomal dominant syndromes-5% by hereditary nonpolyposis colorectal cancer (HNPCC) and 1% by familial adenomatous polyposis (FAP)-the cause of the remaining 14% of familial aggregates of CRC is unknown. Many cases of HNPCC are due to germline mutations in DNA mismatch repair genes, leading to the tumor phenotype of microsatellite instability (MSI), and most cases of FAP are caused by germline APC mutations. To date, non-FAP familial CRC aggregates have not been evaluated for germline APC mutations. In this study, we examined the involvement of germline APC mutations in 79 individuals with CRC who had early-age onset of their cancer (age < 50 years) and/or a family history of CRC. Cases with FAP or HNPCC due to defective mismatch repair were excluded from the study. Using conformation-sensitive gel electrophoresis and the protein truncation test as the screening methods, no functionally significant germline mutations were detected for any of the cases. An apparently silent polymorphism resulting in a 1-bp alteration of A --> G (proline --> proline) in exon 4 was observed. Additionally, four intervening sequence (IVS) alterations were detected: IVS2-53t-->c in 3 cases; IVS4-17ins T in 3 cases; IVS5+32t-->c in 16 cases; and IVS5+33g-->a in 1 case. All appeared to be polymorphisms present in similar proportions in an average-risk population. We conclude that germline APC mutations do not account for familial MSS (stable microsatellite) CRC associated with few synchronous polyps.


Assuntos
Pareamento Incorreto de Bases/genética , Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais/genética , Reparo do DNA/genética , Genes APC/genética , Mutação em Linhagem Germinativa/genética , Adulto , Idade de Início , Idoso , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Conformação de Ácido Nucleico , Deleção de Sequência/genética
14.
Mayo Clin Proc ; 76(1): 29-33, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11155409

RESUMO

OBJECTIVE: To evaluate the accuracy of digital image analysis (DIA) for distinguishing between benign and malignant strictures of the biliary tract. PATIENTS AND METHODS: Our pathology databank was used to identify all biliary brush cytology specimens obtained during endoscopic retrograde cholangiopancreatography between June 1997 and June 1999. Corresponding medical records were reviewed to determine whether patients had benign or malignant strictures. Strictures were further classified into benign strictures with negative routine cytology, malignant strictures with negative routine cytology, and malignant strictures with positive routine cytology. Papanicolaou-stained smears of available brush cytology specimens were destained and then restained with Feulgen dye. Nuclear images were quantified for DNA content without knowledge of stricture type. DNA histograms were generated and ploidy results compared with the class of stricture. RESULTS: We analyzed 27 specimens from 69 confirmed benign or malignant strictures. Assuming that the presence of any aneuploid cells indicated malignancy, the sensitivity of DIA was 85%. Furthermore, aneuploid cells were detected by DIA in 13 of 16 specimens in which routine cytology was unrevealing. CONCLUSION: Ploidy assessment by DIA has potential to enhance the sensitivity of diagnosing malignant strictures compared with routine cytology alone.


Assuntos
Neoplasias dos Ductos Biliares/patologia , Colangiopancreatografia Retrógrada Endoscópica/métodos , Análise Citogenética , Aumento da Imagem/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Aneuploidia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
15.
Fam Cancer ; 1(2): 87-92, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-14574003

RESUMO

Hereditary nonpolyposis colorectal cancer syndrome (HNPCC) is an autosomal dominant condition accounting for 2-5% of all colorectal carcinomas as well as a small subset of endometrial, upper urinary tract and other gastrointestinal cancers. An assay to detect the underlying defect in HNPCC, inactivation of a DNA mismatch repair enzyme, would be useful in identifying HNPCC probands. Monoclonal antibodies against hMLH1 and hMSH2, two DNA mismatch repair proteins which account for most HNPCC cancers, are commercially available. This study sought to investigate the potential utility of these antibodies in determining the expression status of these proteins in paraffin-embedded formalin-fixed tissue and to identify key technical protocol components associated with successful staining. A set of 20 colorectal carcinoma cases of known hMLH1 and hMSH2 mutation and expression status underwent immunoperoxidase staining at multiple institutions, each of which used their own technical protocol. Staining for hMSH2 was successful in most laboratories while staining for hMLH1 proved problematic in multiple labs. However, a significant minority of laboratories demonstrated excellent results including high discriminatory power with both monoclonal antibodies. These laboratories appropriately identified hMLH1 or hMSH2 inactivation with high sensitivity and specificity. The key protocol point associated with successful staining was an antigen retrieval step involving heat treatment and either EDTA or citrate buffer. This study demonstrates the potential utility of immunohistochemistry in detecting HNPCC probands and identifies key technical components for successful staining.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Testes Genéticos , Técnicas Imunoenzimáticas/normas , Proteínas de Neoplasias/genética , Proteínas Adaptadoras de Transdução de Sinal , Anticorpos Monoclonais , Pareamento Incorreto de Bases , Proteínas de Transporte , Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais Hereditárias sem Polipose/imunologia , Reparo do DNA , Diagnóstico Diferencial , Humanos , Técnicas Imunoenzimáticas/estatística & dados numéricos , Cooperação Internacional , Laboratórios/normas , Proteína 1 Homóloga a MutL , Proteínas de Neoplasias/imunologia , Proteínas Nucleares , Variações Dependentes do Observador , Linhagem , Reprodutibilidade dos Testes
16.
Medicine (Baltimore) ; 79(5): 293-8, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11039077

RESUMO

Most reports describe an increased risk of malignancy in Peutz-Jeghers syndrome (PJS). We identified individuals with PJS-like pigmentation but no polyposis, designated as isolated mucocutaneous melanotic pigmentation (IMMP), and 1) characterized their clinical features, 2) assessed them for cancer events, and 3) screened a sample of these subjects for mutations in LKB1, a gene responsible for a portion of PJS cases. Review of Mayo Clinic records from 1945 to 1996 identified 26 patients with IMMP. All were then interviewed or their medical records reviewed to determine if cancer had developed. Conformation-sensitive gel electrophoresis (CSGE) screening for LKB1 mutations was followed by direct sequencing. Ten of these 26 individuals (38%) developed 12 malignancies that arose in the cervix (n = 3), endometrium (n = 3), breast (n = 1), kidney (n = 1), lung (n = 2), colon (n = 1), and lymphatic tissue (n = 1). In females with IMMP, the relative risk for cancer was 3.2 (95% CI, 1.2-6.9), while that for males was not increased. The relative risk for breast and gynecologic cancers was 7.8 (95% CI, 2.5-18.1) in affected females. Of 9 individuals tested, no LKB1 mutations were detected. Classical PJS is associated with an increased cancer risk. Our results indicate that IMMP is another lentiginosis with cancer predisposition. In particular, the relative risk for cancer in females with IMMP was significantly increased, as is true in females with PJS. However, LKB1 mutations did not contribute to the development of IMMP in the patients tested.


Assuntos
Neoplasias da Mama/complicações , Neoplasias dos Genitais Femininos/complicações , Síndrome de Peutz-Jeghers/complicações , Transtornos da Pigmentação/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/genética , Neoplasias do Colo/complicações , Neoplasias do Colo/genética , Feminino , Genes Supressores de Tumor , Neoplasias dos Genitais Femininos/genética , Análise Heteroduplex , Humanos , Neoplasias Renais/complicações , Neoplasias Renais/genética , Masculino , Pessoa de Meia-Idade , Mucosa Bucal , Mutação , Síndrome de Peutz-Jeghers/genética , Proteínas Serina-Treonina Quinases/genética , Risco , Fatores de Risco
17.
J Clin Gastroenterol ; 31(3): 250-3, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11034010

RESUMO

Cetirizine, a human metabolite of hydroxyzine, is a selective H1-receptor antagonist currently approved for the treatment of seasonal allergic rhinitis, perennial allergic rhinitis, and chronic urticaria. In U.S. clinical trials, transient reversible hepatic transaminase elevations were observed in <2% of patients during cetirizine therapy. We report a case of cetirizine-induced cholestasis in a 28-year-old man with no previous hepatobiliary disease after a 2-year period of taking cetirizine on a daily basis. The treatment of this patient included the use of ursodeoxycholic acid, as well as hydroxyzine, for symptomatic relief of pruritus. In light of the patient's clinical and biochemical improvement while using hydroxyzine, it appears that the hepatic metabolism of hydroxyzine to metabolites, including cetirizine, is not involved in the pathogenesis of this particular case of drug-induced hepatotoxicity. Cetirizine should be considered as a potential cause of drug-induced cholestasis.


Assuntos
Cetirizina/efeitos adversos , Colestase Intra-Hepática/induzido quimicamente , Antagonistas dos Receptores Histamínicos H1/efeitos adversos , Adulto , Cetirizina/uso terapêutico , Colestase Intra-Hepática/diagnóstico , Colestase Intra-Hepática/patologia , Antagonistas dos Receptores Histamínicos H1/uso terapêutico , Humanos , Fígado/patologia , Masculino , Rinite Alérgica Perene/tratamento farmacológico
18.
Cancer Res ; 60(17): 4678-81, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10987266

RESUMO

A highly selective, p.o. bioavailable irreversible inhibitor of epidermal growth factor receptor (EGFR) tyrosine kinase, N-[4-(3-chloro4-fluorophenylamino)-quinazolin-6-yl]-ac rylamide (CFPQA), was evaluated for its ability to prevent intestinal adenoma formation in ApcMin mice. Ten-week continuous dietary exposure to CFPQA at doses sufficient to abolish intestinal EGFR tyrosine phosphorylation failed to affect intestinal tumor multiplicity or distribution but induced flat mucosal lesions in the duodenum characteristic of chronic injury. Intestinal trefoil factor, an intestinal peptide that mediates antiapoptotic effects through an EGFR-dependent mechanism, was notably absent in adenomas but was highly expressed in flat duodenal lesions. We conclude that chronic inhibition of EGFR tyrosine kinase by CFPQA does not prevent adenomas in ApcMin mice but may induce duodenal injury.


Assuntos
Acrilamidas/uso terapêutico , Adenoma/prevenção & controle , Anticarcinógenos/uso terapêutico , Neoplasias Duodenais/prevenção & controle , Inibidores Enzimáticos/uso terapêutico , Receptores ErbB/antagonistas & inibidores , Genes APC/fisiologia , Mucinas , Proteínas Musculares , Neuropeptídeos , Quinazolinas/uso terapêutico , Acrilamidas/sangue , Adenoma/genética , Adenoma/metabolismo , Animais , Anticarcinógenos/toxicidade , Relação Dose-Resposta a Droga , Neoplasias Duodenais/genética , Neoplasias Duodenais/metabolismo , Inibidores Enzimáticos/toxicidade , Receptores ErbB/metabolismo , Feminino , Predisposição Genética para Doença , Substâncias de Crescimento/biossíntese , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Peptídeos , Fosforilação , Biossíntese de Proteínas , Quinazolinas/sangue , Transdução de Sinais/fisiologia , Fator Trefoil-2 , Fator Trefoil-3
19.
Transplantation ; 70(2): 292-7, 2000 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-10933151

RESUMO

BACKGROUND: End-stage liver disease for which no cause can be identified, cryptogenic cirrhosis, is a common indication for liver transplantation. Allograft inflammation and fibrosis have been reported to recur with similar frequencies after liver transplantation for cryptogenic cirrhosis and hepatitis C (HCV). METHODS: We determined sequential posttransplant allograft histology in four groups of recipients: 31 transplanted for cryptogenic cirrhosis, 70 for cholestatic etiologies, 40 for alcoholic liver disease, and 56 for HCV. Modified hepatitis activity index (HAI) and fibrosis stage were determined at 4 months, 1 year, and at most recent biopsy posttransplantation. RESULTS: The prevalence of HAI > or = 2 among cryptogenic recipients was similar to that of cholestatic and alcoholic recipients at 4 months, 1 year, and at most recent evaluation (mean 45+/-17 months posttransplantation). For HCV-infected recipients, the frequency of HAI > or = 2 was more than for cryptogenic recipients at 1 year (52 vs. 29%, P=0.04) and at most recent evaluation (64 vs. 15%, P=0.003). Fibrosis scores for cryptogenic, cholestatic, and alcoholic recipients were similar at all timepoints. The proportion of HCV-infected recipients with fibrosis stage >2 was more than that of cryptogenic recipients at 4 months (29 vs. 12%, P=0.05), 1 years (46 vs. 7%, P=0.0002), and at most recent evaluation (42 vs. 15%, P=0.06). None of the cryptogenic recipients developed cirrhosis. RESULTS: The frequency of elevated HAI and fibrosis stage in recipients who undergo transplantation for cryptogenic cirrhosis is similar to that of recipients who undergo transplantation for cholestatic etiologies and significantly less than that of HCV-infected recipients. Fibrosis stage and HAI are generally stable after transplantation for cryptogenic cirrhosis. These data do not suggest a viral etiology of liver disease in the majority of patients with cryptogenic cirrhosis.


Assuntos
Colestase Intra-Hepática/cirurgia , Hepatite C/cirurgia , Cirrose Hepática Alcoólica/cirurgia , Cirrose Hepática/cirurgia , Transplante de Fígado , Transplante Homólogo/patologia , Biópsia , Fígado Gorduroso/patologia , Humanos , Tolerância Imunológica/fisiologia , Fígado/patologia , Cirrose Hepática/etiologia , Transplante de Fígado/patologia , Masculino
20.
Arch Pathol Lab Med ; 124(7): 979-94, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10888773

RESUMO

BACKGROUND: Under the auspices of the College of American Pathologists, the current state of knowledge regarding pathologic prognostic factors (factors linked to outcome) and predictive factors (factors predicting response to therapy) in colorectal carcinoma was evaluated. A multidisciplinary group of clinical (including the disciplines of medical oncology, surgical oncology, and radiation oncology), pathologic, and statistical experts in colorectal cancer reviewed all relevant medical literature and stratified the reported prognostic factors into categories that reflected the strength of the published evidence demonstrating their prognostic value. Accordingly, the following categories of prognostic factors were defined. Category I includes factors definitively proven to be of prognostic import based on evidence from multiple statistically robust published trials and generally used in patient management. Category IIA includes factors extensively studied biologically and/or clinically and repeatedly shown to have prognostic value for outcome and/or predictive value for therapy that is of sufficient import to be included in the pathology report but that remains to be validated in statistically robust studies. Category IIB includes factors shown to be promising in multiple studies but lacking sufficient data for inclusion in category I or IIA. Category III includes factors not yet sufficiently studied to determine their prognostic value. Category IV includes factors well studied and shown to have no prognostic significance. MATERIALS AND METHODS: The medical literature was critically reviewed, and the analysis revealed specific points of variability in approach that prevented direct comparisons among published studies and compromised the quality of the collective data. Categories of variability recognized included the following: (1) methods of analysis, (2) interpretation of findings, (3) reporting of data, and (4) statistical evaluation. Additional points of variability within these categories were defined from the collective experience of the group. Reasons for the assignment of an individual prognostic factor to category I, II, III, or IV (categories defined by the level of scientific validation) were outlined with reference to the specific types of variability associated with the supportive data. For each factor and category of variability related to that factor, detailed recommendations for improvement were made. The recommendations were based on the following aims: (1) to increase the uniformity and completeness of pathologic evaluation of tumor specimens, (2) to enhance the quality of the data needed for definitive evaluation of the prognostic value of individual prognostic factors, and (3) ultimately, to improve patient care. RESULTS AND CONCLUSIONS: Factors that were determined to merit inclusion in category I were as follows: the local extent of tumor assessed pathologically (the pT category of the TNM staging system of the American Joint Committee on Cancer and the Union Internationale Contre le Cancer [AJCC/UICC]); regional lymph node metastasis (the pN category of the TNM staging system); blood or lymphatic vessel invasion; residual tumor following surgery with curative intent (the R classification of the AJCC/UICC staging system), especially as it relates to positive surgical margins; and preoperative elevation of carcinoembryonic antigen elevation (a factor established by laboratory medicine methods rather than anatomic pathology). Factors in category IIA included the following: tumor grade, radial margin status (for resection specimens with nonperitonealized surfaces), and residual tumor in the resection specimen following neoadjuvant therapy (the ypTNM category of the TNM staging system of the AJCC/UICC). (ABSTRACT TRUNCATED)


Assuntos
Neoplasias Colorretais/patologia , Biomarcadores Tumorais , Antígeno Carcinoembrionário/sangue , Neoplasias Colorretais/genética , Neoplasias Colorretais/secundário , DNA de Neoplasias/análise , DNA de Neoplasias/genética , Humanos , Metástase Linfática , Índice Mitótico , Região Organizadora do Nucléolo/patologia , Patologia Clínica , Prognóstico , Sociedades Médicas , Estados Unidos
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