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Lauren Classification (lauren + classification)
Selected AbstractsThe Relationship Between Helicobacter pylori Infection, the Virulence Genotypes of the Infecting Strain and Gastric Cancer in the African SettingHELICOBACTER, Issue 4 2001J. A. Louw Abstract Background. The relationship between Helicobacter pylori infection and gastric carcinoma remains controversial, especially in the African setting where infection is common, while gastric cancer is perceived to be uncommon, the basis of the so called ,African enigma'. This discrepancy between infection and the development of disease is commonly attributed to differences in host, environment and bacterial factors. Interest in the bacterial factors has focused on heterogeneity in the so-called ,virulence genes'. Aim. The aim of this prospective, case-controlled study was to establish whether H. pylori infection is significantly associated with gastric cancer and to investigate whether gastric cancer is associated with genotypically distinct (as it relates to the candidate virulence genes) organisms in this population. Methods. Patients with histologically confirmed gastric cancer were matched with nonulcer dyspeptic controls for age (within 5 years), gender and ethnicity. Helicobacter pylori status was determined by RUT, histology, culture and serology (locally validated and used as default determinant of H. pylori status). Tumors were classified according to the Lauren classification. The ,virulence genotype' of 17 paired culture samples was determined by previously described and validated molecular techniques (cagA presence, vacA alleles, structure of the cag pathogenicity island and analysis of the iceA alleles). Categorical variables were analysed by the ,2 test. Results. Forty-eight patients (median age 59 years) could be adequately matched to controls. 39/48 (81%) cases and 43/48 (90%) controls were H. pylori positive (NS). Significant differences in the virulence genotypes of infecting strains were noted: vacAs2-controls 24%, cases 0%, p < .00001; vacAs1 present , cases 100%, controls 76%, p < .05; cagA -3,-length > 650 bp , cases 47%, controls 0%, p < .002; cag pathogenicity island intact , cases 82%, controls 43%, p < .04; iceA1 , cases 53%, controls 6%, p < .005. cagA was found in all subjects. Conclusion. This study indicates that, in this African population at least, there is no difference in the prevalence of H. pylori infection when comparing gastric cancer cases with matched controls. However, the findings suggest that gastric cancer may be associated with infection by organisms that are genotypically different from those not associated with disease. [source] E-cadherin expression in early gastric carcinoma and correlation with lymph node metastasisJOURNAL OF SURGICAL ONCOLOGY, Issue 5 2007Dong Yi Kim MD Abstract Objective Abnormal expression of E-cadherin plays an important role in the differentiation and progression of gastric carcinoma. However, the relationship between molecular changes in E-cadherin and metastasis in early gastric carcinoma (EGC) is poorly understood. Materials and Methods Sixty cases of EGC with or without lymph node metastasis (30 node-positive cases and 30 node-negative cases) were investigated to evaluate hypermethylation status using bisulfate-MSP and immunohistochemistry using antibody against E-cadherin. Results Twenty-seven (45.0%) of 60 primary EGCs exhibited methylation in the CpG island of E-cadherin. Abnormal expression of E-cadherin was significantly correlated with patient age, tumor size, Lauren classification, differentiation, and lymph node metastasis. Using multiple logistic regression analysis, two factors were independent, statistically significant parameters associated with lymph node metastasis: abnormal expression of E-cadherin (risk ratio, 2.62; 95% confidence interval, 0.917,7.457; P,<,0.05) and lymphatic invasion (risk ratio, 8.11; 95% confidence interval, 1.612,40.766; P,<,0.05). Conclusion Our results suggest that methylation of E-cadherin is a frequent, early event in gastric carcinoma progression, and is correlated significantly with downregulated E-cadherin expression. Inactivation of E-cadherin might be involved in metastasis in EGC and play an important role in microscopic differentiation. J. Surg. Oncol. 2007;96:429,435. © 2007 Wiley-Liss, Inc. [source] Homeoprotein Cdx2 and nuclear PTEN expression profiles are related to gastric cancer prognosis,APMIS, Issue 12 2007ZHIGANG BAI The aim of the study was to analyze the expression of Cdx2 and nuclear PTEN in relation to clinicopathological features of gastric cancer tissue biopsies in order to determine the value of a combined analysis of Cdx2 and nuclear PTEN expression in distinguishing histological types and prognosis of gastric cancers. The expression of Cdx2 and nuclear PTEN was studied using immunohistochemistry of paraffin-embedded tumor specimens from 99 patients who underwent radical D2 gastrectomy between 1999 and 2001. Cdx2 and nuclear PTEN expression were detected in 39.6% (36 of 91) and 70.3% (64 of 91) of gastric cancer cases, respectively. There was a negative correlation between Cdx2 expression and Lauren classification (p=0.032), and between nuclear PTEN expression and lymph node metastasis (p=0.049). Patients with Cdx2-positive, or nuclear PTEN-positive expression had higher survival rates than those with Cdx2-negative or nuclear PTEN-negative expression (p<0.001 and p=0.003, respectively). Co-expression of Cdx2 and nuclear PTEN showed significantly lower levels in diffuse- or mixed-type cancers than in intestinal-type cancers (p=0.005). Multivariate analysis revealed that Cdx2 expression was an independent prognostic indicator of gastric cancer (p=0.014). These data suggest that combined analysis of Cdx2 and nuclear PTEN expression can have significant value in distinguishing histological types of gastric cancer and assessing prognosis in patients with gastric cancer. [source] Role of PTEN and MMP-7 expression in growth, invasion, metastasis and angiogenesis of gastric carcinomaPATHOLOGY INTERNATIONAL, Issue 10 2003Hua-Chuan Zheng To investigate the role of PTEN and matrix metalloproteinase-7 (MMP-7) expression in tumorigenesis and progression of gastric carcinoma, their expression in 113 gastric carcinomas was studied by immunohistochemistry. Microvessel density (MVD) was counted using the anti-CD34 antibody. The expressions of PTEN and MMP-7, and MVD were compared with the clinicopathological parameters of tumors, and the relationship between PTEN and MMP-7 expression and MVD was analyzed. It was found that PTEN was expressed less frequently in primary gastric carcinoma cells than in adjacent epithelial cells (P < 0.05), whereas this was reversed for MMP-7 (P < 0.05). PTEN expression was negatively correlated with invasion, metastasis, growth pattern, Lauren's classification and histological classification (P < 0.05). Matrix metalloproteinase-7 expression was positively associated with tumor size, Borrmann's classification, invasive depth, metastasis and TNM staging (P < 0.05), but negative with PTEN expression (P < 0.05). A positive correlation of MVD with tumor size, invasive depth, metastasis and TNM staging was found (P < 0.05). Microvessel density depended on decreased PTEN expression and increased MMP-7 expression (P < 0.05). The results of the present study suggested that down-regulated PTEN expression and up-regulated MMP-7 expression were greatly implicated in tumorigenesis and progression of gastric carcinoma. Close correlation between PTEN on MMP-7 expression provided a novel insight into the regulatory effects of PTEN on MMP-7 expression in gastric carcinoma. [source] | ||||||||||