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2.
Endoscopy ; 45(7): 553-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23780842

RESUMO

BACKGROUND AND STUDY AIMS: It can be difficult to distinguish adenomas from benign polyps during routine colonoscopy. High resolution microendoscopy (HRME) is a novel method for imaging colorectal mucosa with subcellular detail. HRME criteria for the classification of colorectal neoplasia have not been previously described. Study goals were to develop criteria to characterize HRME images of colorectal mucosa (normal, hyperplastic polyps, adenomas, cancer) and to determine the accuracy and interobserver variability for the discrimination of neoplastic from non-neoplastic polyps when these criteria were applied by novice and expert microendoscopists. METHODS: Two expert pathologists created consensus HRME image criteria using images from 68 patients with polyps who had undergone colonoscopy plus HRME. Using these criteria, HRME expert and novice microendoscopists were shown a set of training images and then tested to determine accuracy and interobserver variability. RESULTS: Expert microendoscopists identified neoplasia with sensitivity, specificity, and accuracy of 67 % (95 % confidence interval [CI] 58 % - 75 %), 97 % (94 % - 100 %), and 87 %, respectively. Nonexperts achieved sensitivity, specificity, and accuracy of 73 % (66 % - 80 %), 91 % (80 % - 100 %), and 85 %, respectively. Overall, neoplasia were identified with sensitivity 70 % (65 % - 76 %), specificity 94 % (87 % - 100 %), and accuracy 85 %. Kappa values were: experts 0.86; nonexperts 0.72; and overall 0.78. CONCLUSIONS: Using the new criteria, observers achieved high specificity and substantial interobserver agreement for distinguishing benign polyps from neoplasia. Increased expertise in HRME imaging improves accuracy. This low-cost microendoscopic platform may be an alternative to confocal microendoscopy in lower-resource or community-based settings.


Assuntos
Pólipos Adenomatosos/classificação , Colonoscopia/métodos , Neoplasias Colorretais/classificação , Pólipos Intestinais/classificação , Pólipos Adenomatosos/patologia , Colo/patologia , Neoplasias Colorretais/patologia , Humanos , Hiperplasia , Mucosa Intestinal/patologia , Pólipos Intestinais/patologia , Microscopia de Fluorescência , Variações Dependentes do Observador , Reto/patologia , Sensibilidade e Especificidade , Gravação em Vídeo
3.
Mucosal Immunol ; 3(6): 633-44, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20664576

RESUMO

Tumor necrosis factor α (TNFα) is a key pathogenic factor in Crohn's disease and rheumatoid arthritis. TNF(ΔARE) mice express high levels of TNFα and present Crohn's-like ileitis and arthritis. Alterations in the chemokine network could underline the TNF-driven ileitis. The aim of this study was to evaluate the role of TNF and chemokines in ileitis using ectromelia virus cytokine response modifier D (CrmD), a protein that binds TNFα and a limited number of chemokines. We generated transgenic mice expressing CrmD in intestinal epithelial cells (vCrmD mice) and crossed them with the TNF(ΔARE) mice to test whether CrmD could affect TNF-driven inflammatory processes. During homeostasis, only the number of B cells in the lamina propria was reduced by CrmD expression. Interestingly, CrmD expression in the intestine markedly attenuated the inflammatory infiltrates in the ileum of TNF(ΔARE) mice, but did not affect development of arthritis. Our results suggest that CrmD affects development of ileitis by locally affecting both TNF and chemokine function in the ileum.


Assuntos
Linfócitos B/metabolismo , Doença de Crohn/imunologia , Vírus da Ectromelia/imunologia , Mucosa Intestinal/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Febre Reumática/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Virais/metabolismo , Animais , Artrite , Linfócitos B/imunologia , Linfócitos B/patologia , Proteínas de Transporte/genética , Proteínas de Transporte/imunologia , Proteínas de Transporte/metabolismo , Células Cultivadas , Doença de Crohn/genética , Doença de Crohn/patologia , Doença de Crohn/fisiopatologia , Modelos Animais de Doenças , Humanos , Ileíte , Inflamação , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Camundongos , Camundongos Mutantes , Camundongos Transgênicos , Mutação/genética , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/imunologia , Febre Reumática/genética , Febre Reumática/patologia , Febre Reumática/fisiopatologia , Transgenes/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Proteínas Virais/genética , Proteínas Virais/imunologia
4.
Colorectal Dis ; 11(4): 428-9, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-18662238

RESUMO

This is a report of adenocarcinoma arising in an ileal pouch after restorative proctocolectomy (RPC) with rectal mucosal stripping performed by Cavitron Ultrasonic Surgical Aspirator (CUSA) for ulcerative colitis. The CUSA was introduced to simplify and optimize ileal pouch-anal anastomosis with mucosectomy and has been shown to shorten the operative time and reduce blood loss. Its use however, may increase the number of pathology specimens made uninterpretable on account of tissue ablation. In the present case, even though preoperative colonoscopy had clearly shown dysplasia, the surgical pathology report could not detect any neoplasia in the specimen; hence, the patient was not surveyed for pouch cancer. Six years later, the patient presented with intestinal obstruction caused by cancer. While protocols for universal pouch surveillance remain somewhat controversial, we conclude on the basis of this case and a review of the literature that in RPC with mucosectomy performed by CUSA, pouch cancer surveillance is particularly important because remnants of rectal epithelium may have been left behind and tissue ablation may have made the surgical pathology report uninterpretable.


Assuntos
Adenocarcinoma/cirurgia , Neoplasias do Ânus/cirurgia , Colite Ulcerativa/cirurgia , Recidiva Local de Neoplasia , Proctocolectomia Restauradora/métodos , Neoplasias Vaginais/secundário , Adenocarcinoma/complicações , Adenocarcinoma/secundário , Adulto , Neoplasias do Ânus/complicações , Colite Ulcerativa/complicações , Evolução Fatal , Feminino , Mucosa Gástrica/cirurgia , Humanos , Proctocolectomia Restauradora/instrumentação , Neoplasias Vaginais/cirurgia
5.
Colorectal Dis ; 8(7): 539-43, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16919103

RESUMO

Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessively inherited disorder consisting of the triad of oculocutaneous tyrosinase-positive albinism, prolonged bleeding time secondary to platelet storage pool defect and ceroid depositions within the reticuloendothelial system. Some patients also reportedly have gastrointestinal (GI) complications related to chronic granulomatous colitis, enterocolitis and extensive granulomatous perianal disease, the later previously unreported in the literature. These observations suggest that the GI complications of HPS are due to the development of classical Crohn's disease. The implications for disease pathogenesis and surgical management are discussed.


Assuntos
Doença de Crohn/etiologia , Enterocolite/etiologia , Síndrome de Hermanski-Pudlak/complicações , Doenças Retais/etiologia , Adulto , Criança , Pré-Escolar , Doença de Crohn/patologia , Feminino , Síndrome de Hermanski-Pudlak/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade
6.
J Microsc ; 220(Pt 3): 190-204, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16364002

RESUMO

A region growing algorithm for segmentation of human intestinal gland images is presented. The initial seeding regions are identified based on the large vacant regions (lumen) inside the intestinal glands by fitting with a very large moving window. The seeding regions are then expanded by repetitive application of a morphological dilate operation with a much smaller round window structure set. False gland regions (nongland regions initially misclassified as gland regions) are removed based on either their excessive ages of active growth or inadequate thickness of dams formed by the strings of goblet cell nuclei sitting immediately outside the grown regions. The goblet cell nuclei are then identified and retained in the image. The gland contours are detected by applying a large moving round window fitting to the enormous empty exterior of the goblet cell nucleus chains in the image. The assumptions based on real intestinal gland images include the closed chain structured goblet cell nuclei that sit side-by-side with only small gaps between the neighbouring nuclei and that the lumens enclosed by the goblet cell nucleus chains are most vacant with only occasional run-away nuclei. The method performs well for most normal and abnormal intestinal gland images although it is less applicable to cancer cases. The experimental results show that the segmentations of the real microscopic intestinal gland images are satisfactorily accurate based on the visual evaluations.


Assuntos
Células Caliciformes/citologia , Aumento da Imagem/métodos , Intestinos/anatomia & histologia , Adenocarcinoma/patologia , Adenoma/patologia , Algoritmos , Núcleo Celular , Diagnóstico por Imagem , Humanos , Neoplasias Intestinais/patologia
7.
Leukemia ; 18(12): 1948-50, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15470489

RESUMO

Grb7, a noncatalytic intracellular adaptor protein involved in cell migration, is overexpressed in certain invasive and metastatic solid tumors. We found a highly significant difference in the level of expression of Grb7 between chronic lymphocytic leukemia (CLL) cells obtained from stage I and stage IV patients (P<0.001). Using semiquantitative RT-PCR, we detected high levels of Grb7 in 88% of stage IV patients vs only 18% in stage I patients. A corresponding increase was found in the in vitro migration of stage IV CLL cells in comparison to stage I cells. The statistically significant difference in the expression of Grb7 between stage IV and stage I patients was preserved even when tested specifically in the ZAP70-positive group (P<0.01). These findings show that Grb7 levels reflect the severity of the disease, and may be used, in conjunction with ZAP70, to predict disease progression.


Assuntos
Movimento Celular , Leucemia Linfocítica Crônica de Células B/metabolismo , Proteínas/metabolismo , Estudos de Casos e Controles , Células Cultivadas , Doença , Progressão da Doença , Receptores ErbB/genética , Receptores ErbB/metabolismo , Proteína Adaptadora GRB7 , Humanos , Leucemia Linfocítica Crônica de Células B/patologia , Linfócitos/metabolismo , Linfócitos/patologia , Estadiamento de Neoplasias , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Proteínas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína-Tirosina Quinase ZAP-70
8.
Transplant Proc ; 36(2): 335-7, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15050150

RESUMO

Acute cellular rejection remains a serious and frequent complication during the posttransplant course of small bowel allograft recipients. Currently, small bowel biopsies are the optimal method to identify this form of rejection. The morphological criteria for this diagnosis have been known for some time; however, no consensus study has classified these changes. To address issues in bowel transplant pathology, several pathologists experienced in this particular subdiscipline participated in a Pathology Workshop preceding the VIIIth International Small Bowel Transplant Symposium in Miami, Florida. Among the results of this workshop was the development a standardized grading scheme for acute cellular rejection in small bowel transplants.


Assuntos
Rejeição de Enxerto/patologia , Intestino Delgado/transplante , Transplante Homólogo/patologia , Biópsia , Diagnóstico Diferencial , Humanos , Intestino Delgado/patologia , Reprodutibilidade dos Testes , Transplante Homólogo/imunologia
9.
Gastroenterology ; 120(4): 820-6, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11231935

RESUMO

BACKGROUND & AIMS: Unlike ulcerative colitis, there are few reports on the efficacy of surveillance colonoscopy in patients with chronic Crohn's colitis and therefore little agreement as to whether routine surveillance is indicated. We report on 259 patients with chronic Crohn's colitis who underwent screening and subsequent surveillance colonoscopy and biopsy since 1980. METHODS: Biopsies were performed at 10-cm intervals and from strictures and polypoid masses. Pathology was classified as normal, dysplasia (indefinite, low-grade, high-grade), or carcinoma. RESULTS: A total of 663 examinations were performed on 259 patients. The median interval between examinations was 24 months; examinations were performed more frequently (1-6 months) in patients with dysplasia on biopsy. A thinner-caliber colonoscope was required to complete 12% of screening examinations and 23% of surveillance examinations. The pediatric colonoscope helped increase our yield of neoplasia by 19%. The screening and surveillance program detected dysplasia or cancer in 16% (10 indefinite, 23 low-grade, and 4 high-grade dysplasias and 5 cancers). A finding of definite dysplasia or cancer was associated with age >45 years and increased symptoms. By life table analysis, the probability of detecting dysplasia or cancer after a negative screening colonoscopy was 22% by the fourth surveillance examination. CONCLUSIONS: Colonoscopic surveillance should be strongly considered in chronic extensive Crohn's colitis.


Assuntos
Colonoscopia , Doença de Crohn/patologia , Programas de Rastreamento , Vigilância da População/métodos , Adolescente , Adulto , Carcinoma/patologia , Criança , Pré-Escolar , Doença Crônica , Colite/patologia , Colo/patologia , Neoplasias do Colo/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
Am J Gastroenterol ; 96(3): 818-21, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11280557

RESUMO

OBJECTIVE: In the nearly 20 yr since collagenous colitis was first recognized, the results of therapies have not been systematically described in substantial numbers of patients. We have therefore conducted a retrospective analysis of 26 patients treated in this institution during the years 1991-1994. METHODS: Twenty-nine cases of collagenous colitis were obtained by review of biopsy specimens collected between 1991 and 1994 at The Mount Sinai Hospital. Each chart was reviewed for patient demographics, symptoms, coexisting conditions, specific therapies, and therapeutic outcomes. Additional data were obtained from telephone calls to patients when deemed necessary. Three patients were exeluded from the study because of lack of follow-up. Therapeutic outcomes were defined as follows: Complete Remission (CR): normalization of bowel function; Partial Remission (PR): 50% reduction in frequency of bowel movements; Failure: <50% reduction in frequency of bowel movements; or Relapse: return of symptoms after cessation of treatment. Median follow-up was 58 wk from time of diagnosis, with a range of 22-376 wk. RESULTS: The 26 patients (25 women, one man) had a mean age of 62 yr (range, 22-85 yr) at diagnosis. Of 26 patients, 22 responded to some form of therapy and one had spontaneous remission. Six of the responders ultimately remained in CR with no therapy. Twelve are maintained on 5-aminosalicylic acid (5-ASA) and or antidiarrheals to control symptoms. An additional six required prednisone throughout the follow-up period to remain in CR or PR. Two patients failed all therapy. CONCLUSION: Collagenous colitis is a treatable condition in most patients. We recommend initial therapy with antidiarrheals, followed by a trial of 5-ASA agent. A trial of 5-ASA in combination with prednisone should be attempted in patients refractory to 5-ASA alone, with subsequent attempts in the responders to taper prednisone and maintain remission with no therapy, if possible, or with 5-ASA and/or antidiarrheal agents if necessary.


Assuntos
Colite/tratamento farmacológico , Colite/metabolismo , Colágeno/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Antidiarreicos/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Masculino , Mesalamina/uso terapêutico , Pessoa de Meia-Idade , Prednisona/uso terapêutico , Estudos Retrospectivos
11.
J Comput Assist Tomogr ; 25(2): 239-41, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11242221

RESUMO

Multifocal idiopathic fibrosclerosis (also called multifocal fibrosclerosis) is an uncommon disease in which there is a systemic overgrowth of fibrous tissues, with a spectrum of aggressiveness ranging from benign retroperitoneal fibrosis to pachymeningitis. We describe the first case of gastric involvement of multifocal fibrosclerosis and its appearance on CT.


Assuntos
Colangite Esclerosante/diagnóstico por imagem , Gastropatias/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Colangite Esclerosante/patologia , Feminino , Fibrose , Humanos , Esclerose , Gastropatias/patologia
12.
Cancer Res ; 60(17): 4864-8, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10987299

RESUMO

Twelve to 15% of sporadic colorectal cancers display defective DNA mismatch repair (MMR), manifested as microsatellite instability (MSI). In this group of cancers, promoter hypermethylation of the MMR gene hMLH1 is strongly associated with, and believed to be the cause of, MSI. A subset of colorectal neoplastic lesions arising in inflammatory bowel disease (IBD) is also characterized by MSI. We wished to determine whether hMLH1 hypermethylation was associated with diminished hMLH1 protein expression and MSI in IBD neoplasms. We studied 148 patients with IBD neoplasms, defined as carcinoma or dysplasia occurring in patients with ulcerative colitis or Crohn's disease. MSI was evaluated using multiplex fluorescent PCR to amplify loci D2S123, BAT-25, BAT-26, D5S346, and D17S250 in all cases. Lesions were characterized as high-frequency MSI (MSI-H) if they manifested instability at two or more loci, low-frequency MSI (MSI-L) if unstable at only one locus, or MS-stable (MSS) if showing no instability at any loci. Methylation-specific PCR was performed to determine the methylation status of the hMLH1 promoter region. hMLH1 protein expression was also evaluated by immunohistochemistry. Thirteen (9%) of 148 neoplasms arising in IBD were MSI-H, comprising 11 carcinomas and 2 dysplastic lesions. Sixteen additional lesions (11%) were MSI-L, comprising 11 carcinomas and 5 dysplastic lesions. The remaining 118 neoplasms (80%) were MSS. Six (46%) of 13 MSI-H, 1 (6%) of 16 MSI-L, and 4 (15%) of 27 MSS lesions showed hMLH1 hypermethylation (P = 0.013). Diminished hMLH1 protein expression in neoplastic cell nuclei relative to surrounding normal cell nuclei was demonstrated immunohistochemically in four of four (100%) hypermethylated lesions tested. In IBD neoplasia, hMLH1 promoter hypermethylation occurs frequently in the setting of MSI, particularly MSI-H. Furthermore, hMLH1 hypermethylation and MSI are strongly associated with diminished hMLH1 protein expression in IBD neoplasms. These findings suggest that hMLH1 hypermethylation causes defective DNA MMR in at least a subset of IBD neoplasms.


Assuntos
Neoplasias Colorretais/genética , Metilação de DNA , Reparo do DNA/genética , Doenças Inflamatórias Intestinais/genética , Repetições de Microssatélites/genética , Proteínas de Neoplasias/genética , Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Transporte , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/metabolismo , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Inativação Gênica , Humanos , Imuno-Histoquímica , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/metabolismo , Proteína 1 Homóloga a MutL , Proteínas de Neoplasias/biossíntese , Proteínas Nucleares , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas/genética
14.
Gastroenterology ; 117(6): 1295-300, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10579970

RESUMO

BACKGROUND & AIMS: Adenomatous polyps are by definition dysplastic and pathologically indistinguishable from the dysplasia-associated lesion or mass (DALM) described in 1981. Yet, adenomatous polyps in noncolitic colons are usually removed definitively endoscopically, whereas DALMs are regarded as harbingers of colon cancer, mandating colectomy. METHODS: Since 1988, all of our patients with chronic ulcerative or Crohn's colitis and dysplastic polyps and no coexistent dysplasia in flat mucosa underwent colonoscopic polypectomy. Biopsy specimens were obtained also adjacent to polypectomy sites, from strictures, and throughout the colon at 10-cm intervals. Follow-up colonoscopies and biopsies were performed within 6 months after polypectomy and yearly thereafter. RESULTS: Colonoscopy in 48 patients with chronic colitis (mean duration, 25.4 years) resected 70 polyps (60 in colitic and 10 in noncolitic mucosa). Polyps were detected on screening colonoscopies (29%) and on surveillance (71%). Pathology was tubular adenoma in all polyps from noncolitic mucosa and low-grade dysplasia (57), high-grade dysplasia (2), or carcinoma (1) in polyps from colitic mucosa. Subsequent colonoscopies (mean follow-up, 4.1 years) revealed additional polyps in 48% but no carcinomas. Surgical resection (6 patients) for recurrent polyps confirmed colonoscopic findings. No dysplasia or cancers in flat mucosa were found at surgery or on follow-up colonoscopies. CONCLUSIONS: In patients with chronic colitis who have no dysplasia in flat mucosa, colonoscopic resection of dysplastic polyps can be performed effectively, just as in noncolitic colons.


Assuntos
Adenoma/cirurgia , Colite/cirurgia , Pólipos do Colo/cirurgia , Adenoma/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Colite/diagnóstico , Pólipos do Colo/diagnóstico , Colonoscopia , Demografia , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento
15.
Oncogene ; 18(26): 3902-4, 1999 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10445854

RESUMO

A germline sequence alteration at codon 1307 of the APC gene (I1307K) has been reported in 6-7% of the Ashkenazi Jewish population in the United States. This alteration is believed to predispose the APC gene to a secondary mutation at the same locus, resulting in an increased risk of colorectal carcinoma. There is an increased risk of colorectal carcinoma in patients with inflammatory bowel disease (IBD), a relatively large proportion of whom are Ashkenazi Jews. We therefore sought to determine whether the I1307K sequence variant occurred in the germline DNA of IBD patients. To our surprise, we found this sequence in only two of 267 patients with IBD (0.7%), occurring in only 1.5% of Jewish IBD patients. The I1307K sequence variant was not found in 67 patients with esophageal cancer, 53 patients with gastric carcinoma (13 MSI-H and 44 MSI-negative), or ten patients with sporadic MSI-H colon cancer. These findings suggest that the I1307K sequence is relatively rare in the germline of Jewish as well as non-Jewish IBD patients. It does not appear to contribute to the increased colorectal cancer risk present in these patients.


Assuntos
Genes APC , Doenças Inflamatórias Intestinais/genética , Judeus/genética , Neoplasias Colorretais/etnologia , Neoplasias Colorretais/genética , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Doenças Inflamatórias Intestinais/etnologia , Risco
16.
J Foot Ankle Surg ; 38(3): 214-8, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10384361

RESUMO

The authors present a case of bilateral Hawkins type II talar neck fractures sustained during a motocross race in a 23 year old man. Due to the complexity of the injuries, open reduction with internal fixation and primary subtalar joint arthrodesis was performed bilaterally. This is one of the few cases of bilateral talar neck fractures reported in the literature in the past 15 years and one of the first utilizing open reduction and internal fixation with concomitant subtalar joint arthrodesis as a primary treatment.


Assuntos
Fraturas Ósseas/etiologia , Fraturas Cominutivas/cirurgia , Traumatismo Múltiplo , Veículos Off-Road , Articulação Talocalcânea/lesões , Tálus/lesões , Adulto , Artrodese , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/classificação , Fraturas Ósseas/fisiopatologia , Humanos , Masculino , Articulação Talocalcânea/cirurgia
17.
Oncogene ; 15(1): 101-5, 1997 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-9233782

RESUMO

FHIT (fragile histidine triad gene), a candidate tumor suppressor gene, was recently identified and cloned at chromosome 3p14.2. Alterations of this gene have been reported in a number of primary human tumors, including colorectal, esophageal, gastric and lung carcinomas. However, some reports have found no abnormalities in this gene. We investigated a total of 63 primary esophageal tumors, nine esophageal cancer cell lines and 17 ulcerative colitis-associated neoplasms (UCANs) for alterations of FHIT. In 13 esophageal tumors, we employed overlapping reverse transcriptase-PCRs (RT-PCRs) to amplify and sequence the complete open reading frame of FHIT. One of 13 primary esophageal tumors analysed by RT-PCR expressed no detectable FHIT transcript; the remaining 12 expressed normal-sized transcripts with wild-type open reading frame sequences. In an additional 50 esophageal tumors, the polymorphic microsatellite loci D3S1300 and D3S1313 were used to evaluate loss of heterozygosity (LOH) at 3p14.2. Eleven of these 50 tumors showed LOH at one or both loci. In all these 11 tumors, genomic PCR and direct sequencing of FHIT exons 5-9 was performed. This analysis revealed that none of these 11 primary esophageal tumors contained any alterations in the FHIT open reading frame or adjacent intron sequences. Finally, among 17 UCANs, the in vitro synthesized protein (IVSP) assay detected no truncated protein products, nor were there any abnormalities in size or DNA sequence of FHIT RT-PCR products. However, in six of nine esophageal carcinoma cell lines, no FHIT RT-PCR product was detectable using either of the overlapping primer sets. Genomic PCR and direct sequencing of exons 5-9, also performed in these nine cell lines, revealed wild-type sequence in eight cell lines; however, one cell line contained no exon 5 PCR product. This cell line also lacked detectable FHIT transcript. These data suggest that the open reading frame of FHIT is not important in the development or progression of most primary esophageal carcinomas or UCANs, although lack of expression of the FHIT transcript may be common in esophageal cancer-derived cell lines. The possibility of an additional tumor suppressor gene at chromosome 3p14.2 remains to be evaluated.


Assuntos
Hidrolases Anidrido Ácido , Colite Ulcerativa/genética , Neoplasias Esofágicas/genética , Mutação , Proteínas/genética , Deleção Cromossômica , Humanos , Proteínas de Neoplasias/genética , Reação em Cadeia da Polimerase , Células Tumorais Cultivadas
18.
Cancer Res ; 57(12): 2350-3, 1997 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-9192806

RESUMO

The E2F group of transcription factors transactivates genes that promote progression through the G1-S transition of the cell cycle. Members of the retinoblastoma (Rb) family of proteins bind to E2Fs and inhibit this function. E2F-4, one example of the E2F group, functions as an oncogene when transfected into nontransformed cells in vitro. On the other hand, mice that are homozygously lacking a normal E2F-1 gene develop cancers, consistent with a tumor-suppressive role for this gene. The exact function of E2Fs has thus been unclear; moreover, direct involvement of this gene in primary human tumorigenesis has not been shown. We, therefore, investigated mutation within the E2F-4 coding region in 16 primary gastric adenocarcinomas, 12 ulcerative colitis-associated neoplasms, 46 sporadic colorectal carcinomas, 9 endometrial cancers, and 3 prostatic carcinomas. We limited our investigation to the serine repeat within E2F-4, reasoning that this tract might be altered in genetically unstable tumors (replication error-positive, or RER+). All tumors were RER+, with the exception of a control group of 15 RER- sporadic colorectal carcinomas. PCR with incorporation of [32P]dCTP was performed using primers flanking the serine trinucleotide (AGC) repeat. Twenty-two of 59 gastrointestinal tumors (37%) contained E2F-4 mutations; these comprised 5 of 16 gastric tumors (31%), 4 of 12 ulcerative colitis-associated neoplasms (33%, including 1 dysplastic lesion), and 13 of 31 sporadic colorectal cancers (42%). No mutation was present in any of the endometrial, prostate, or RER- colorectal tumors. Of note, homozygous mutations occurred in three cases, and two of seven informative patients showed loss of one E2F-4 allele in their tumors. Furthermore, the RER+ sporadic colorectal tumors were evaluated at trinucleotide repeats within the genes for N-cadherin and B-catenin; no tumors demonstrated mutation of these genes. These data suggest that E2F-4 is a target of defective DNA repair in these tumors.


Assuntos
Adenocarcinoma/genética , Proteínas de Ligação a DNA/genética , Neoplasias Gastrointestinais/genética , Mutação , Transativadores , Fatores de Transcrição/genética , Alelos , Caderinas/genética , Deleção Cromossômica , Proteínas do Citoesqueleto/genética , DNA de Neoplasias/genética , Fator de Transcrição E2F4 , Neoplasias do Endométrio/genética , Feminino , Heterozigoto , Humanos , Masculino , Neoplasias da Próstata/genética , beta Catenina
19.
Am J Gastroenterol ; 92(4): 682-5, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9128324

RESUMO

OBJECTIVES: To determine the frequency and outcome of carcinoid tumors in a large series of patients with inflammatory bowel disease (IBD). METHODS: Eleven patients with carcinoid tumors associated with IBD were admitted or readmitted to The Mount Sinai Hospital between 1960 and 1995. These cases were derived from two sources, seven from our clinical series of 3326 IBD patients (0.2%) and four more recent cases from the records of our Pathology Department. Six of the cases were associated with Crohn's disease and five with ulcerative colitis. RESULTS: Nine of the 11 carcinoids were found in the appendix, and 2 were found in the ileum. All carcinoids were found incidentally after surgery for IBD; none of the patients had distant metastases or carcinoid syndrome. Of the 11 cases, 3 were associated with an additional noncarcinoid tumor: 2 with adenocarcinoma of the colon and 1 with endometrial carcinoma. CONCLUSIONS: There appears to be no evidence to substantiate a direct association between IBD and carcinoid tumor, because almost all cases were found incidentally after surgery for IBD, with a frequency in operated IBD patients similar to that reported for patients without IBD.


Assuntos
Tumor Carcinoide/patologia , Neoplasias do Colo/patologia , Doenças Inflamatórias Intestinais/patologia , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adolescente , Adulto , Tumor Carcinoide/cirurgia , Neoplasias do Colo/cirurgia , Feminino , Humanos , Doenças Inflamatórias Intestinais/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
20.
Gastroenterology ; 112(1): 40-5, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8978341

RESUMO

BACKGROUND & AIMS: Numerous gastrointestinal tumors, notably sporadic and ulcerative colitis (UC)-associated colorectal carcinomas and dysplasias, gastric cancers, and esophageal carcinomas, manifest microsatellite instability. Recently, a transforming growth factor beta 1 type II receptor (TGF-beta 1RII) mutation in a coding microsatellite was described in colorectal carcinomas showing instability. One hundred thirty-eight human neoplasms (61 UC-associated, 35 gastric, 26 esophageal, and 16 sporadic colorectal) were evaluated for this TGF-beta 1RII mutation. METHODS: Whether instability was present at other chromosomal loci in these lesions was determined. In lesions manifesting or lacking instability, the TGF-beta 1RII coding region polydeoxyadenine (poly A) microsatellite tract was polymerase chain reaction amplified with 32P-labeled deoxycytidine triphosphate. Polymerase chain reaction products were electrophoresed on denaturing gels and exposed to radiographic film. RESULTS: Three of 18 UC specimens with instability at other chromosomal loci (17%) showed TGF-beta 1RII poly A tract mutation, including 2 cancers and 1 dysplasia; moreover, 2% of UC specimens without instability (1 of 43) (1 cancer), 81% of unstable sporadic colorectal cancers (13 of 16), and none of the 61 stable or unstable gastric or esophageal cancers contained TGF-beta 1RII mutations. CONCLUSIONS: Mutational inactivation of the poly A microsatellite tract within TGF-beta 1RII occurs early and in a subset of unstable UC neoplasms and commonly in sporadic colorectal cancers but may be rare in unstable gastric and esophageal tumors.


Assuntos
Receptores de Ativinas Tipo I , Adenocarcinoma/genética , Carcinoma/genética , Colite Ulcerativa/genética , Neoplasias Colorretais/genética , Neoplasias Esofágicas/genética , Repetições de Microssatélites/genética , Mutação/genética , Proteínas Serina-Treonina Quinases/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Neoplasias Gástricas/genética , Genes Supressores de Tumor/genética , Humanos , Receptor do Fator de Crescimento Transformador beta Tipo I
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