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1.
Oxf Med Case Reports ; 2018(7): omy039, 2018 Jul.
Article in English | MEDLINE | ID: mdl-30046450

ABSTRACT

Delayed gastrointestinal metastasis is a rare complication of hepatocellular carcinoma (HCC). We present the case of a patient who presented with melaena and microcytic anaemia 6 years after receiving an orthotopic liver transplant for hepatitis B-induced HCC. Oesophagogastroduodenoscopy revealed a fungating gastric mass at the lesser curve and histology from biopsies confirmed metastatic recurrence of HCC in the stomach. The route of metastasis is likely due to iatrogenic seeding of tumour cells during pre-transplant endoscopic ultrasound (EUS) and fine needle aspiration (FNA) biopsy. Subsequent positron emission tomography and magnetic resonance imaging failed to reveal further metastatic disease and the patient was managed with a total gastrectomy. This is the first reported description in the literature of needle-track metastasis in the stomach due to liver EUS-FNA for HCC.

2.
Clin Oncol (R Coll Radiol) ; 26(4): 197-202, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24485884

ABSTRACT

AIMS: The pathology of tumours after chemo/radiotherapy for locally advanced rectal cancer can be difficult to interpret. The ypTNM staging does not accurately predict outcomes. Therefore, we developed a new prognostic index for this purpose. MATERIALS AND METHODS: The Nottingham Rectal Cancer Prognostic Index (NRPI) is based on a study of 158 patients with locally advanced rectal cancer treated with preoperative chemo/radiotherapy at Nottingham University Hospital between April 2001 and December 2008. Patients were treated with radiotherapy to a dose of 50 Gy in 25 fractions over 5 weeks with/without concurrent capecitabine chemotherapy. Surgery was carried out after an interval of 6-10 weeks. Factors found to be significant on univariate analysis to predict for disease-free (DFS) and overall survival were further explored in multivariate analysis. The significant factors (Mandard tumour regression grade, perineural invasion, circumferential resection margin status and nodal status) were weighted to establish a score for the index. The median follow-up was 40 months (range 3-90 months). RESULTS: On survival analysis, four distinct prognostic groups were found: Score 0 = excellent prognosis, 1-3 = good prognosis, 4-8 = moderate prognosis, 9-14 = poor prognosis. The NRPI significantly predicted both DFS and overall survival (P < 0.0001). DFS at 5 years was 95, 63, 25 and 0% for the four groups. On multivariate analysis the NRPI was found to be the strongest predictor of DFS including nodal and circumferential resection margin status (P < 0.0001). It was a stronger predictor of overall survival than the American Joint Committee on Cancer/Dukes staging (P < 0.0001). CONCLUSIONS: The NRPI allocates patients into distinct prognostic categories. This seems to be a much stronger predictive factor than the American Joint Committee on Cancer/Dukes staging. This requires further validation, but seems to be a useful clinical index for future studies.


Subject(s)
Rectal Neoplasms/drug therapy , Rectal Neoplasms/radiotherapy , Adult , Aged , Aged, 80 and over , Chemoradiotherapy , Female , Humans , Lymphatic Metastasis , Male , Middle Aged , Neoplasm Grading , Neoplasm Invasiveness , Neoplasm Staging , Prognosis , Rectal Neoplasms/pathology , Rectal Neoplasms/surgery , Rectum/injuries , Survival Rate , Treatment Outcome
4.
Cell Microbiol ; 15(12): 2080-92, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23870035

ABSTRACT

Helicobacter pylori establishes a chronic lifelong infection in the human gastric mucosa, which may lead to peptic ulcer disease or gastric adenocarcinoma. The human beta-defensins (hßDs) are antimicrobial peptides, hßD1 being constitutively expressed in the human stomach. We hypothesized that H. pylori may persist, in part, by downregulating gastric hßD1 expression. We measured hßD1 and hßD2 expression in vivo in relation to the presence, density and severity of H. pylori infection, investigated differential effects of H. pylori virulence factors, and studied underlying signalling mechanisms in vitro. Significantly lower hßD1 and higher hßD2 mRNA and protein concentrations were present in gastric biopsies from infected patients. Those patients with higher-level bacterial colonization and inflammation had significantly lower hßD1 expression, but there were no differences in hßD2. H. pylori infection of human gastric epithelial cell lines also downregulated hßD1. Using wild-type strains and isogenic mutants, we showed that a functional cag pathogenicity island-encoded type IV secretion system induced this downregulation. Treatment with chemical inhibitors or siRNA revealed that H. pylori usurped NF-κB signalling to modulate hßD1 expression. These data indicate that H. pylori downregulates hßD1 expression via NF-κB signalling, and suggest that this may promote bacterial survival and persistence in the gastric niche.


Subject(s)
Helicobacter Infections/immunology , Helicobacter pylori/metabolism , Immune Evasion/immunology , beta-Defensins/biosynthesis , Bacterial Secretion Systems , Cell Line , Down-Regulation , Gastric Mucosa/immunology , Gastric Mucosa/metabolism , Gastric Mucosa/microbiology , Helicobacter Infections/metabolism , Helicobacter Infections/microbiology , Helicobacter pylori/immunology , Helicobacter pylori/pathogenicity , Humans , Mitogen-Activated Protein Kinase 1/genetics , NF-kappa B p50 Subunit/genetics , RNA Interference , RNA, Messenger/biosynthesis , RNA, Small Interfering , Signal Transduction , Stomach/immunology , Stomach/microbiology , Transcription Factor RelA/genetics , beta-Defensins/genetics
5.
Ann R Coll Surg Engl ; 95(2): e38-40, 2013 Mar.
Article in English | MEDLINE | ID: mdl-23484980

ABSTRACT

Neurofibromas of the common bile duct are extremely rare. The lack of specific clinical or radiological features makes preoperative diagnosis in the absence of histology difficult. We report the case of a female patient who presented with obstructive jaundice and evidence of a common bile duct stricture on imaging. She underwent an exploratory laparotomy, and intraoperative frozen section confirmed clear margins and a benign lesion. Excision of the extrahepatic bile duct and A Rouxen-Y hepaticojejunostomy was performed. We discuss the clinical features and management of neurofibromas of the bile duct in light of the literature.


Subject(s)
Common Bile Duct Neoplasms/complications , Jaundice, Obstructive/etiology , Neurofibroma/complications , Aged , Common Bile Duct Neoplasms/pathology , Common Bile Duct Neoplasms/surgery , Female , Humans , Jaundice, Obstructive/pathology , Jaundice, Obstructive/surgery , Neurofibroma/pathology , Neurofibroma/surgery
6.
Neurogastroenterol Motil ; 24(4): 318-e163, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22276853

ABSTRACT

BACKGROUND: Recurrent abdominal pain is reported by a third of patients with diverticulosis, particularly those with previous episodes of acute diverticulitis. The current understanding of the etiology of this pain is poor. Our aim was to assess visceral sensitivity in patients with diverticular disease and its association with markers of previous inflammation and neuropeptides. METHODS: Patients with asymptomatic and symptomatic diverticular disease underwent a flexible sigmoidoscopy and biopsy followed 5-10 days later by visceral sensitivity testing with barostat-mediated rectal distension. Inflammation was assessed by staining of serotonin (5HT) and CD3 positive cells. mRNA levels of tumor necrosis factor alpha (TNF α) and interleukin-6 (IL-6) were quantitated using RT-PCR. Neuropeptide expression was assessed from percentage area staining with substance P (SP) and mRNA levels of the neurokinin 1 & 2 receptors (NK1 & NK2), and galanin 1 receptor (GALR1). KEY RESULTS: Thirteen asymptomatic and 12 symptomatic patients were recruited. The symptomatic patients had a lower first reported threshold to pain (28.4 mmHg i.q.r 25.0-36.0) than the asymptomatic patients (47 mmHg i.q.r 36.0-52.5, P < 0.001). Symptomatic patients had a higher median overall pain rating for the stimuli than the asymptomatic patients (P < 0.02). Symptomatic patients had greater median relative expression of NK1 and TNF alpha mRNA compared with asymptomatic patients. There was a significant correlation between barostat VAS pain scores and NK 1 expression (Figure 4, r(2) 0.54, P < 0.02). CONCLUSIONS & INFERENCES: Patients with symptomatic diverticular disease exhibit visceral hypersensitivity, and this may be mediated by ongoing low grade inflammation and upregulation of tachykinins.


Subject(s)
Abdominal Pain/etiology , Diverticulitis, Colonic/complications , Diverticulosis, Colonic/complications , Neuropeptides/biosynthesis , Abdominal Pain/metabolism , Abdominal Pain/pathology , Aged , Diverticulitis, Colonic/metabolism , Diverticulitis, Colonic/pathology , Diverticulosis, Colonic/metabolism , Diverticulosis, Colonic/pathology , Female , Humans , Hyperesthesia/etiology , Hyperesthesia/metabolism , Hyperesthesia/pathology , Inflammation/complications , Inflammation/metabolism , Inflammation/pathology , Male , Middle Aged , Pain Threshold/physiology , RNA, Messenger/analysis , Real-Time Polymerase Chain Reaction , Receptors, Neuropeptide/biosynthesis , Reverse Transcriptase Polymerase Chain Reaction , Viscera/metabolism , Viscera/pathology
9.
Eur J Cancer ; 47(8): 1138-45, 2011 May.
Article in English | MEDLINE | ID: mdl-21220198

ABSTRACT

PURPOSE: To assess the prognostic value of the Mandard tumour regression score (TRG) following pre-operative chemo/radiotherapy in patients with locally advanced rectal cancer. METHODS AND MATERIALS: The study involved 158 patients with locally advanced rectal cancer treated with pre-operative long course chemo/radiotherapy at Nottingham University Hospital between April 2001 and December 2008. Patients were treated with radiotherapy to a dose of 50 Gy in 25 fractions over 5 weeks with or without concurrent capecitabine chemotherapy at a dose of 1650 mg/m(2)/day. Surgery was normally performed after an interval of 6-10 weeks. The response to pre-operative treatment was carefully graded by a single pathologist using the five point Mandard score. The median follow-up was 40 months (range 3-90 months). RESULTS: Of the 158 patients 14% were TRG1, 41% were TRG2, 31% were TRG3, 13% were TRG4 and 1% were TRG5. The groups were combined into TRG1, TRG2 and TRG3-5 to simplify further analysis. The Mandard score was clearly related to both disease-free (p < 0.001) and overall survival (p = 0.012). On multivariate analysis perineural invasion, nodal status, TRG and circumferential resection margin status were the most powerful predictors of disease-free survival. CONCLUSIONS: The Mandard tumour regression score is an independent prognostic factor and predicts for long-term outcome following pre-operative chemo/radiotherapy in rectal cancer.


Subject(s)
Rectal Neoplasms/diagnosis , Adult , Aged , Aged, 80 and over , Disease-Free Survival , Dose-Response Relationship, Radiation , Drug Therapy/methods , Humans , Middle Aged , Multivariate Analysis , Neoplasm Staging/methods , Prognosis , Proportional Hazards Models , Radiotherapy/methods , Rectal Neoplasms/therapy , Treatment Outcome
10.
J Viral Hepat ; 18(1): 23-31, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20196799

ABSTRACT

Assessment of liver fibrosis is important in determining prognosis and evaluating interventions. Due to limitations of accuracy and patient hazard of liver biopsy, non-invasive methods have been sought to provide information on liver fibrosis, including the European liver fibrosis (ELF) test, shown to have good diagnostic accuracy for the detection of moderate and severe fibrosis. Access to independent cohorts of patients has provided an opportunity to explore if this test could be simplified. This paper reports the simplification of the ELF test and its ability to identity severity of liver fibrosis in external validation studies in patients with chronic hepatitis C (CHC). Paired biopsy and serum samples from 347 naïve patients with CHC in three independent cohorts were analysed. Diagnostic performance characteristics were derived (AUROC, sensitivity and specificity, predictive values), and clinical utility modelling performed to determine the proportion of biopsies that could have been avoided if ELF test was used in this patient group. It was possible to simplify the original ELF test without loss of performance and the new algorithm is reported. The simplified ELF test was able to predict severe fibrosis [pooled AUROC of 0.85 (95% CI 0.81-0.89)] and using clinical utility modelling to predict severe fibrosis (Ishak stages 4-6; METAVIR stages 3 and 4) 81% of biopsies could have been avoided (65% correctly). Issues of spectrum effect in diagnostic test evaluations are discussed. In chronic hepatitis C a simplified ELF test can detect severe liver fibrosis with good accuracy.


Subject(s)
Biomarkers/blood , Hepatitis C, Chronic/complications , Immunoassay/methods , Liver Cirrhosis/diagnosis , Adolescent , Adult , Aged , Algorithms , Cohort Studies , Female , Humans , Hyaluronic Acid/blood , Liver/pathology , Liver Cirrhosis/etiology , Liver Cirrhosis/pathology , Male , Middle Aged , Peptide Fragments/blood , Predictive Value of Tests , Procollagen/blood , Sensitivity and Specificity , Severity of Illness Index , Tissue Inhibitor of Metalloproteinase-1/blood , Young Adult
12.
Br J Surg ; 97(8): 1269-78, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20602499

ABSTRACT

BACKGROUND: This study investigated the association of mucins and cluster of differentiation (CD) 56 with vascular and perineural invasion and survival in patients with periampullary cancer. METHODS: Immunohistochemical staining was performed on formalin-fixed pancreatic tissue microarrays (cancer, chronic pancreatitis and normal pancreatic tissue) constructed from 126 pancreatic resections (cancer, 104; chronic pancreatitis, 22). Mucin (MUC) 1, MUC4 and MUC5AC expression was quantified using the immunohistochemical score (range 0-300), MUC3 expression was described as membranous or cytoplasmic, and expression of CD56, MUC2 and MUC6 as present or absent. RESULTS: In cancers, vascular invasion correlated with overexpression (immunohistochemical score of 100 or more) of MUC1 (P = 0.003) and presence of MUC6 (P = 0.024), and perineural invasion correlated with overexpression of MUC5AC (P = 0.015). Reduced survival was observed with overexpression of MUC4 (P = 0.032) and MUC5AC (P = 0.048), membranous expression of MUC3 (P = 0.048), and presence of CD56 (P = 0.041). Perineural invasion also correlated with CD56 expression (P = 0.001). Overexpression of MUC4 and MUC5AC correlated with tumour recurrence (P = 0.001 and P = 0.034 respectively). Multivariable analysis identified membranous expression of MUC3 (P = 0.023), lymphatic invasion (P = 0.015) and perineural invasion (P = 0.004) as independent predictors of poor survival. CONCLUSION: Mucins and CD56 may be markers of prognosis in patients with periampullary cancer.


Subject(s)
Ampulla of Vater , Biomarkers, Tumor/metabolism , CD56 Antigen/metabolism , Common Bile Duct Neoplasms/diagnosis , Mucins/metabolism , Aged , Ampulla of Vater/pathology , Common Bile Duct Neoplasms/mortality , Common Bile Duct Neoplasms/pathology , Female , Humans , Immunohistochemistry , Kaplan-Meier Estimate , Male , Middle Aged , Neoplasm Invasiveness , Pancreatitis, Chronic/diagnosis , Prognosis
13.
Br J Cancer ; 102(4): 704-9, 2010 Feb 16.
Article in English | MEDLINE | ID: mdl-20087352

ABSTRACT

BACKGROUND: Altered DNA repair may be associated with aggressive tumour biology and impact upon response to chemotherapy and radiotherapy. We investigated whether expression of human AP endonuclease (APE1), a key multifunctional protein involved in DNA BER, would impact on clinicopathological outcomes in ovarian, gastro-oesophageal, and pancreatico-biliary cancer. METHODS: Formalin-fixed human ovarian, gastro-oesophageal, and pancreatico-biliary cancers were constructed into TMAs. Expression of APE1 was analysed by IHC and correlated to clinicopathological variables. RESULTS: In ovarian cancer, nuclear APE1 expression was seen in 71.9% (97 out of 135) of tumours and correlated with tumour type (P=0.006), optimal debulking (P=0.009), and overall survival (P=0.05). In gastro-oesophageal cancers previously exposed to neoadjuvant chemotherapy, 34.8% (16 out of 46) of tumours were positive in the nucleus and this correlated with shorter overall survival (P=0.005), whereas cytoplasmic localisation correlated with tumour dedifferentiation (P=0.034). In pancreatico-biliary cancer, nuclear staining was seen in 44% (32 out of 72) of tumours. Absence of cytoplasmic staining was associated with perineural invasion (P=0.007), vascular invasion (P=0.05), and poorly differentiated tumours (P=0.068). A trend was noticed with advanced stage (P=0.077). CONCLUSIONS: Positive clinicopathological correlations of APE1 expression suggest that APE1 is a potential drug target in ovarian, gastro-oesophageal, and pancreatico-biliary cancers.


Subject(s)
Biliary Tract Neoplasms/diagnosis , Carcinoma/diagnosis , DNA-(Apurinic or Apyrimidinic Site) Lyase/physiology , Esophageal Neoplasms/diagnosis , Ovarian Neoplasms/diagnosis , Pancreatic Neoplasms/diagnosis , Stomach Neoplasms/diagnosis , Adult , Aged , Aged, 80 and over , Biliary Tract Neoplasms/metabolism , Biliary Tract Neoplasms/mortality , Carcinoma/metabolism , Carcinoma/mortality , DNA-(Apurinic or Apyrimidinic Site) Lyase/genetics , Esophageal Neoplasms/metabolism , Esophageal Neoplasms/mortality , Female , Gene Frequency , Humans , Male , Middle Aged , Ovarian Neoplasms/metabolism , Ovarian Neoplasms/mortality , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/mortality , Polymorphism, Single Nucleotide , Prognosis , Stomach Neoplasms/metabolism , Stomach Neoplasms/mortality , Survival Analysis
14.
Clin Oncol (R Coll Radiol) ; 21(1): 23-31, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19027272

ABSTRACT

AIMS: To determine tumour regression (volume-halving time) obtained after chemo/radiotherapy, and thereby the ideal interval between the start of treatment and surgery in order to obtain a high rate of complete response. MATERIALS AND METHODS: In total, 106 patients with cT3,4 rectal cancer who received preoperative radiotherapy alone or concurrently with capecitabine chemotherapy at Nottingham City Hospital, UK were studied. The rectal tumour volume visible on the computed tomography planning scan was compared with the residual pathological volume and the tumour volume-halving time calculated. The radiotherapy response was graded according to the Mandard system. RESULTS: Fifty-three patients had radiotherapy alone, with 53 patients having concurrent chemoradiotherapy. The median tumour volume-halving time was found to be 14 days and not influenced by the addition of chemotherapy. The Mandard score, the interval from the start of treatment to surgery and the tumour volume-halving time were statistically associated with tumour regression. The median tumour volume in our series of 54 cm(3) would require an interval of 20 weeks after the start of treatment to surgery to regress to <0.1 cm(3) (10 volume-halving times; 140 days). CONCLUSIONS: The initial tumour volume and median volume-halving time provide the best estimates for determining the optimum length of interval between the completion of preoperative chemo/radiotherapy and surgery in locally advanced rectal cancer.


Subject(s)
Antimetabolites, Antineoplastic/therapeutic use , Deoxycytidine/analogs & derivatives , Fluorouracil/analogs & derivatives , Neoadjuvant Therapy , Rectal Neoplasms/surgery , Adult , Aged , Aged, 80 and over , Capecitabine , Deoxycytidine/therapeutic use , Female , Fluorouracil/therapeutic use , Humans , Male , Middle Aged , Radiotherapy, Conformal , Rectal Neoplasms/drug therapy , Rectal Neoplasms/pathology , Rectal Neoplasms/radiotherapy
16.
Gut ; 57(10): 1375-85, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18467372

ABSTRACT

BACKGROUND AND AIMS: Helicobacter pylori infection is the major cause of peptic ulceration and gastric adenocarcinoma. To address the hypothesis that the human acquired immune response to H. pylori influences pathogenesis, we characterised the gastric T helper (Th) and regulatory T cell (Treg) response of infected patients. METHODS: The human gastric CD4(+) T cell response of 28 donors who were infected with H. pylori and 44 who were not infected was analysed using flow cytometry. The T cell associated mucosal cytokine response was analysed by real-time polymerase chain reaction assay of samples from 38 infected and 22 uninfected donors. Recombinant interleukin 10 (IL10) was added to co-cultures of H. pylori and AGS cells and its suppressive effects upon inflammatory responses were measured. RESULTS: We found that the H. pylori-specific response consists of both T helper 1 and 2 subsets with high levels of IL10-secreting Tregs. People with peptic ulcer disease had a 2.4-fold reduced CD4(+)CD25(hi)IL10(+) Treg response (p = 0.05) but increased Th1 and Th2 responses (Th1: 3.2-fold, p = 0.038; Th2: 6.1-fold, p = 0.029) compared to those without ulcers. In vitro studies showed that IL10 inhibited IL8 expression and activation of nuclear factor kappa B induced by H. pylori in gastric epithelial cells, and enhanced H. pylori growth in a bacterial-cell co-culture model. CONCLUSIONS: Together our data suggest that H. pylori induces a regulatory T cell response, possibly contributing to its peaceful coexistence with the human host, and that ulcers occur when this regulatory response is inadequate.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , Gastric Mucosa/immunology , Helicobacter Infections/immunology , Helicobacter pylori/immunology , Peptic Ulcer/immunology , Stomach Neoplasms/immunology , Adult , Aged , Aged, 80 and over , Cell Line , Female , Flow Cytometry , Gastric Mucosa/microbiology , Helicobacter pylori/isolation & purification , Humans , Immunity, Cellular , Male , Middle Aged , Polymerase Chain Reaction , Stomach Neoplasms/microbiology
18.
Endoscopy ; 39(8): 725-30, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17620230

ABSTRACT

BACKGROUND AND STUDY AIMS: Both endoscopic ultrasound- (EUS-) guided tissue sampling techniques, fine-needle aspiration (FNA) and Trucut biopsy, have advantages and limitations. The aim of this study was to develop a strategy of combining these two EUS-guided sampling techniques in order to maximize the diagnostic accuracy and minimize duplication. PATIENTS AND METHODS: In this multicenter study we performed "dual sampling" (i. e. with both FNA and Trucut biopsy) in 95 patients during phase 1 of the study and "sequential sampling" (i. e. performing FNA only when Trucut biopsy tissue cores were macroscopically inadequate) in 72 patients during phase 2. RESULTS: During the study period, 167/401 patients referred for EUS-guided sampling were eligible for the study; only solid lesions were included. In 143/167 patients (86 %), sampling was performed via the transesophageal or transgastric routes. When the dual sampling strategy was used, an accurate diagnosis was achieved in 78/95 patients by FNA, compared with 85/95 by Trucut biopsy ( P = 0.21). The combined accuracy of the dual sampling strategy was higher than FNA alone (88/95 vs. 78/95, P = 0.048), but was not significantly higher than Trucut biopsy alone (88/95 vs. 85/95, P = 0.61). Using the sequential sampling strategy, an accurate diagnosis was achieved in 66/72 patients (92 %) compared with 88/95 (93 %) for dual sampling ( P = 1.0), and 8/72 patients (11 %) had to undergo FNA after Trucut biopsy failed to obtain an adequate sample. One patient with mediastinal tuberculosis developed a cold abscess following Trucut biopsy. CONCLUSION: A sequential sampling strategy, in which EUS-guided Trucut biopsy is attempted first, and FNA performed only when Trucut biopsy fails to obtain a macroscopically adequate sample, achieves a diagnostic accuracy of 92 %, with 11 % of patients requiring both sampling procedures.


Subject(s)
Biopsy, Fine-Needle/methods , Endosonography/methods , Pancreatic Neoplasms/diagnostic imaging , Pancreatic Neoplasms/pathology , Biopsy, Needle/methods , Cohort Studies , Female , Humans , Immunohistochemistry , Male , Neoplasm Staging , Reproducibility of Results , Sensitivity and Specificity
20.
J Clin Pathol ; 59(12): 1261-6, 2006 Dec.
Article in English | MEDLINE | ID: mdl-16679349

ABSTRACT

BACKGROUND: The cadherin-catenin complex is the key component of the adherens junction in epithelial cells, and changes in this complex are implicated in gastric adenocarcinoma. Germline mutations in E-cadherin have been described in diffuse-type gastric adenocarcinoma. Helicobacter pylori infection is the first stage in gastric carcinogenesis. AIMS: To determine whether H pylori was associated with changes in the complex, and whether this was affected by virulence of the strain. METHODS: Epithelial cell lines were cultured with H pylori using the wild-type pathogenic and non-pathogenic strains and CagE null and VacA null isogenic mutants. Gastric biopsy specimens at endoscopy were obtained from patients with (n = 17) and without (n = 15) H pylori infection, and E-cadherin and beta-catenin expression was assessed by immunohistochemistry. H pylori was typed by polymerase chain reaction from these patients for CagE and VacA. RESULTS: In vitro studies showed that coculture with a pathogenic strain of H pylori led to disruption of epithelial junctional beta-catenin expression, but without evidence of nuclear translocation or signalling. This effect was independent of a functional Cag pathogenicity island and vacuolating activity, but dependent on live bacteria. No marked differences in beta-catenin or E-cadherin expression were seen in gastric biopsy specimens in patients with and without H pylori infection. CONCLUSION: Acute H pylori infection disrupts junctional beta-catenin in vitro, but chronic infection by H pylori has no effect on E-cadherin and beta-catenin expression, as seen in gastric biopsy specimens at the initial gastritis stage of the proposed Correa pathway of gastric carcinogenesis. A later effect at the later stages of atrophy or intestinal metaplasia cannot be ruled out.


Subject(s)
Cadherins/metabolism , Catenins/metabolism , Helicobacter Infections/metabolism , Helicobacter pylori , Biopsy , Blotting, Western/methods , Cell Line , Coculture Techniques , Epithelial Cells/metabolism , Gastric Mucosa/metabolism , Gastritis/metabolism , Gastritis/microbiology , Helicobacter Infections/pathology , Helicobacter pylori/classification , Helicobacter pylori/pathogenicity , Humans , Virulence
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