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Intestinal Type (intestinal + type)
Selected AbstractsStatistical Model of the Interactions Between Helicobacter pylori Infection and Gastric Cancer DevelopmentHELICOBACTER, Issue 1 2003Martin Welin ABSTRACT Background. The bacterium Helicobacter pylori is associated with a number of gastrointestinal diseases, such as gastric ulcer, duodenal ulcer and gastric cancer. Several histological changes may be observed during the course of infection; some may influence the progression towards cancer. The aim of this study was to build a statistical model to discover direct interactions between H. pylori and different precancerous changes of the gastric mucosa, and in what order and to what degree those may influence the development of the intestinal type of gastric cancer. Methods. To find direct and indirect interactions between H. pylori and different histological variables, log-linear analyses were used on a case,control study. To generate mathematically and biologically relevant statistical models, a designed algorithm and observed frequency tables were used. Results. The results show that patients with H. pylori infection need to present with proliferation and intestinal metaplasia to develop gastric cancer of the intestinal type. Proliferation and intestinal metaplasia interacted with the variables atrophy and foveolar hyperplasia. Intestinal metaplasia was the only variable with direct interaction with gastric cancer. Gender had no effect on the variables examined. Conclusion. The direct interactions observed in the final statistical model between H. pylori, changes of the mucosa and gastric cancer strengthens and supports previous theories about the progression towards gastric cancer. The results suggest that gastric cancer of the intestinal type may develop from H. pylori infection, proliferation and intestinal metaplasia, while atrophy and foveolar hyperplasia interplay with the other histological variables in the disease process. [source] p16 Immunoreactivity in unusual types of cervical adenocarcinoma does not reflect human papillomavirus infectionHISTOPATHOLOGY, Issue 3 2010Oisin Houghton Houghton O, Jamison J, Wilson R, Carson J & McCluggage W G (2010) Histopathology,57, 342,350 p16 Immunoreactivity in unusual types of cervical adenocarcinoma does not reflect human papillomavirus infection Aims:, The association between human papillomavirus (HPV) and cervical carcinoma is well known, with HPV being identifiable in almost all cervical squamous carcinomas and most adenocarcinomas. However, the prevalence of HPV in unusual morphological types of cervical adenocarcinoma has not been investigated extensively. The aim was to determine HPV status in a series of primary cervical adenocarcinomas, enriched for unusual morphological types. The relationship between HPV and p16 immunoreactivity in these neoplasms was also investigated, as it is generally assumed that in cervical neoplasms diffuse p16 expression is predictive of the presence of high-risk HPV. Methods and results:, Sixty-three cervical adenocarcinomas, comprising those of usual type (n = 43), minimal deviation type (n = 4), gastric type (n = 3), intestinal type (n = 3), mesonephric type (n = 3), clear cell type (n = 4), serous type (n = 2) and hepatoid type (n = 1) underwent linear array HPV genotyping and immunohistochemistry for p16. Overall, HPV was identified in 32 of 56 cases (57%) in which sufficient DNA was present for analysis. The most common HPV types were 16 and 18, with these being identified in 20 and 18 cases, respectively, either alone or in combination. Seventy-eight per cent of usual-type adenocarcinomas were HPV-positive, as was the single serous carcinoma in which there was sufficient DNA for analysis. In contrast, all minimal deviation adenocarcinomas and those of gastric, intestinal, mesonephric and clear cell types were HPV-negative, as was the single hepatoid carcinoma. All usual-type adenocarcinomas exhibited p16 immunoreactivity (diffuse staining in all but one case), as did 11 of 20 of those of unusual morphological type (five focal, six diffuse). Conclusions:, Most, but not all, cervical adenocarcinomas of usual type contain HPV, but those of unusual morphological type are almost always HPV-negative. This has implications for the efficacy of HPV vaccination in the prevention of cervical adenocarcinoma. A significant proportion of cervical adenocarcinomas are p16-positive in the absence of HPV, illustrating that in these neoplasms diffuse p16 immunoreactivity is not a reliable surrogate marker of the presence of high-risk HPV. [source] Cereal fiber intake may reduce risk of gastric adenocarcinomas: The EPIC-EURGAST studyINTERNATIONAL JOURNAL OF CANCER, Issue 7 2007Mendez M.A. Abstract Numerous case-control studies suggest dietary fiber may reduce risk of gastric cancer, but this has not been confirmed prospectively. A previous case-control study reported reduced risk of gastric cardia adenocarcinomas associated with cereal fiber, but not with fruit or vegetable fiber. To date, different food sources of fiber have not been examined with respect to noncardia tumors or diverse histologic sub-types. This study prospectively examines associations between fiber from different food sources and incident gastric adenocarcinomas (GC) among more than 435,000 subjects from 10 countries participating in the European Prospective Investigation into Cancer and Nutrition study. Subjects aged 25,70 years completed dietary questionnaires in 1992,98, and were followed up for a median of 6.7 years. About 312 incident GCs were observed. The relative risk of GC was estimated based on cohort-wide sex-specific fiber intake quartiles using proportional hazards models to estimate hazards ratios (HRs) and 95% confidence intervals (CIs). Intakes of cereal fiber, but not total, fruit or vegetable fiber, were associated with reduced GC risk [adjusted HR for the highest vs. lowest quartile of cereal fiber 0.69, 0.48,0.99]. There was a strong inverse association for diffuse [HR 0.43, 0.22,0.86], but not intestinal type [HR 0.98, 0.54,1.80] tumors. Associations for cardia vs. noncardia tumors were similar to those for overall GC, although cardia associations did not reach significance. Cereal fiber consumption may help to reduce risk of GC, particularly diffuse type tumors. Further study on different food sources of fiber in relation to GC risk is warranted to confirm these relationships. © 2007 Wiley-Liss, Inc. [source] Abnormal Expression of p16INK4a, Cyclin D1, Cyclin-Dependent Kinase 4 and Retinoblastoma Protein in Gastric Carcinomas,JOURNAL OF SURGICAL ONCOLOGY, Issue 1 2008Ichiro Kishimoto MD Abstract Background and Objectives The p16INK4a (p16), cyclin D1, cyclin-dependent kinase (CDK) 4 and retinoblastoma (Rb) genes are components of the Rb pathway that controls the G1-S checkpoint of the cell cycle. The aim of this study was to assess the relationship between their abnormalities and clinicopathological features in gastric carcinomas. Mehtods Immunohistochemical analysis of the encoded proteins was performed on a series of 158 cases. Results Loss of p16/Rb protein (pRb) expression and overexpression of cyclin D1/CDK4 were observed in 49%/40% and 37%/37% of gastric carcinomas, respectively. At least 1 of these abnormalities was found in 86% of the cases and a positive correlation was noted between p16 and pRb (P,=,0.009). Cyclin D1 (P,=,0.042) and CDK4 (P,=,0.008) overexpession was inversely associated with lymph node metastasis and depth of invasion, respectively. Loss of pRb expression was more frequently in diffuse type lesions than in the intestinal type (P,=,0.022). The patients with p16+/pRb,/cyclin D1,/CDK4, or p16,/pRb+/cyclin D1,/CDK4, tumors demonstrated particularly poor survival. With multivariate survival analysis, only depth of invasion and TNM stage could be proven as independent predictors. Conclusions The Rb pathway is disrupted in the vast majority of gastric carcinomas. This study also identified specific immunohistochemical marker profiles for prognosis. J. Surg. Oncol. 2008;98:60,66. © 2008 Wiley-Liss, Inc. [source] Analysis of microsatellite alterations in gastric carcinoma using the crypt isolation techniqueTHE JOURNAL OF PATHOLOGY, Issue 2 2004Yu-Fei Jiao Abstract The crypt isolation technique was used to analyse loss of heterozygosity (LOH) and microsatellite instability (MSI) in gastric carcinomas (36 intestinal type, 17 solid type, and 23 diffuse type) using a polymerase chain reaction assay. Increased LOH frequencies and fractional allelic losses (FAL) were observed in samples prepared using the crypt isolation technique compared with those isolated by the conventional method. A significant increase in LOH was found at several chromosomal loci, and significant differences in FAL were found in patients with intestinal- and solid-type tumours. There was no difference in the frequency of MSI using either technique. In samples prepared by the crypt isolation technique, significant allelic losses (,50%) were observed at most loci tested in intestinal- and solid-type tumours, but not in diffuse-type tumours. Significant losses of some of these loci are novel findings for gastric cancer. FAL values were significantly higher in intestinal- and solid-type tumours than in diffuse-type tumours. MSI-high was observed in intestinal- (17%) and solid-type (12%) tumours. The results suggest that the crypt isolation technique is useful for accurate allelic loss analysis in gastric carcinoma and that LOH and MSI are more common in intestinal- and solid-type tumours than in diffuse-type tumors. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] Distinct promoter hypermethylation of p16INK4a, CDH1, and RAR-beta in intestinal, diffuse,adherent, and diffuse,scattered type gastric carcinomasTHE JOURNAL OF PATHOLOGY, Issue 1 2002Naohide Oue Abstract Hypermethylation of CpG islands in gene promoters is associated with silencing of various tumour suppressor genes. Recent studies of colorectal and gastric carcinomas have defined a CpG island methylator phenotype (CIMP), which involves the targeting of multiple genes by promoter hypermethylation. In this study, methylation-specific polymerase chain reaction (PCR) was performed to study methylation of CpG islands in the promoters of the p16INK4a, cadherin 1 (CDH1), and retinoic acid receptor-beta (RAR-beta) genes in 45 gastric carcinomas and to investigate whether CDH1 and RAR-beta promoter hypermethylation is associated with CIMP-positive gastric carcinoma. CpG island hypermethylation of the p16INK4a, CDH1, and RAR-beta promoters was detected in 12 (27%), 26 (58%), and 24 (53%) of the 45 gastric carcinomas, respectively. Hypermethylation of the p16INK4a promoter was more common in intestinal type than in diffuse type gastric carcinomas (p = 0.0023; Fisher's exact test) and was inversely associated with p53 mutations (p = 0.0225; Fisher's exact test). However, CDH1 and RAR-beta promoter hypermethylation was observed more frequently in diffuse,scattered type gastric carcinoma than in other types (intestinal and diffuse,adherent types) (p = 0.0175 and p = 0.0335, respectively; Fisher's exact test) and was not associated with p53 mutation status. Moreover, hypermethylation of the CDH1 and RAR-beta promoters occurred concordantly (p < 0.0001; Fisher's exact test). These results suggest that at least two types of promoter methylation status are involved in the development of the intestinal (p16INK4a promoter hypermethylation) and diffuse,scattered types (CDH1 and RAR-beta promoter hypermethylation) of gastric carcinoma. Copyright © 2002 John Wiley & Sons, Ltd. [source] | ||||||||||||||||||||||