Over-expression of cyclooxygenase-2 in endoscopic biopsies of ectopic gastric mucosa

A multidisciplinary approach to identifying and managing heterotopic gastric inlet patches

INTRODUCTION

Gastric inlet patches are often incidental, but can also be a treatable cause of laryngo-esophageal symptoms.

METHODS

We retrospectively reviewed all patients whose gastric inlet patches were diagnosed following assessment for laryngopharyngeal and swallowing symptoms. Improvement following Argon Plasma Coagulation (APC) was assessed using Minimum Clinically-Important Difference methodology combining voice, throat, and swallowing domains. Correlations between APC response and measures of reflux and mucosal barrier integrity, measured during 24-h pH-impedance manometry, were obtained. Proximal and Distal Mean Nocturnal Baseline Impedance (MNBI) values were separately calculated and the novel variable of Mucosal Impedance Gradient was derived as [((Distal MNBI-Proximal MNBI)/((Distal MNBI + Proximal MMBI)/2)) x 100].

KEY RESULTS

Inlet patches were detected in 57 of 651 patients who had Transnasal Panendoscopy (8.7 ± 2.2%). There were 34 males. Mean age was 58 years. Mean duration of symptoms was 2 years. The commonest symptoms were hoarseness (n = 33), throat symptoms (n = 24), and dysphagia (n = 21), respectively. APC was used to ablate patches in 34 patients. Treatment response was 71% at a mean followup of 5.5 months. MIG > - 25% predicted response to APC, with area under the receiver operating characteristic curve of 0.875 (Sensitivity = 81%; Specificity = 100%; p < 0.0001).

CONCLUSIONS

Gastric inlet patches are common and under-recognized. They can cause protracted pharyngo-esophageal symptoms. Patch ablation is an effective treatment for carefully selected patients. Optimal patient selection requires multidisciplinary teamwork. Mucosal Impedance Gradient could further refine patient selection.

Ectopic gastric mucosa in the submucosa of the stomach: A case report

Under normal circumstances, gastric mucosa only exists within the stomach. However, in certain situations, gastric mucosal tissue may undergo ectopia, commonly occurring in the esophagus and intestine, with rare occurrences within the stomach itself. A comprehensive literature review was performed to understand the distinct characteristics of ectopic gastric mucosa (EGM) in the stomach and investigate a rare incident of this disease, providing an in-depth analysis of the clinical, histopathologic, and differential diagnostic findings. The case was a 47-year-old man with acid reflux, heartburn, abdominal distension, and diarrhea (5-10 times daily) for >10 years. A gastroscope indicated a submucosal protuberance lesion in the gastric body that felt hard with biopsy forceps. A well-defined nodule under the mucosal muscle was revealed microscopically, composed of epithelial elements and no atypia. Immunohistochemical staining demonstrated similar EGM expression patterns compared with normal gastric mucosa. The present case report highlights the importance of accurate EGM diagnosis and understanding.

Prevalence and Clinical and Endoscopic Characteristics of Cervical Inlet Patch (Heterotopic Gastric Mucosa): A Systematic Review and Meta-Analysis

BACKGROUND

Cervical inlet patch (CIP), also called gastric inlet patch, is a heterotopic columnar mucosal island located in the cervical esophagus, which has been under-recognized by clinicians.

AIM

We conducted a systemic review and meta-analysis to explore the prevalence and clinical and endoscopic characteristics of CIP.

MATERIALS AND METHODS

Studies were searched through the PubMed, EMBASE, and Cochrane Library databases. The prevalence of CIP with 95% confidence interval (CI) was pooled by using a random-effect model. The association of CIP with demographics, clinical presentations, and endoscopic features was evaluated by odds ratios (ORs).

RESULTS

Fifty-three studies including 932,777 patients were eligible. The pooled prevalence of CIP was 3.32% (95% CI=2.86%-3.82%). According to the endoscopic mode, the pooled prevalence of CIP was higher in studies using narrow-band imaging than in those using white light and esophageal capsule endoscopy (9.34% vs. 2.88% and 0.65%). The pooled prevalence of CIP was higher in studies where the endoscopists paid specific attention to the detection of this lesion (5.30% vs. 0.75%). CIP was significantly associated with male (OR=1.24, 95% CI=1.09-1.42, P=0.001), gastroesophageal reflux disease (OR=1.32, 95% CI=1.04-1.68, P=0.03), reflux symptoms (OR=1.44, 95% CI=1.14-1.83, P=0.002), dysphagia (OR=1.88, 95% CI=1.28-2.77, P=0.001), throat discomfort (OR=4.58, 95% CI=1.00-21.02, P=0.05), globus (OR=2.95, 95% CI=1.52-5.73, P=0.001), hoarseness (OR=4.32, 95% CI=1.91-9.78, P=0.0004), cough (OR=3.48, 95% CI=1.13-10.72, P=0.03), Barrett's esophagus (OR=2.01, 95% CI=1.37-2.94, P=0.0003), and esophagitis (OR=1.62, 95% CI=1.27-2.07, P=0.0001).

CONCLUSION

CIP appears to be common by using narrow-band imaging, especially if the endoscopists would like to pay attention to the detection of this lesion. CIP is clearly associated with acid-related symptoms and Barrett's esophagus.

Effect of Helicobacter pylori infection on Barrett's esophagus and esophageal adenocarcinoma formation in a rat model of chronic gastroesophageal reflux

OBJECTIVES

To investigate the relationship between Helicobacter pylori infection and Barrett's esophagus (BE), a rat model of chronic gastroesophageal reflux with H. pylori infection was established and the degree of inflammation, incidence of BE and esophageal adenocarcinoma (EA) were evaluated.

METHODS

Eight-week-old male specific-pathogen-free SD rats were divided into five groups randomly: pseudo-operation group; esophagojejunum anastomosis (EJA) group; EJA with H. pylori infection group; EJA with H. pylori infection and celecoxib-treated group; EJA with celecoxib-treated group. Rats were kept for 30 weeks after surgery. Esophageal lesion was evaluated grossly and microscopically. The expression of COX-2 and CDX2 was determined by RT-PCR and immunohistochemistry staining. The level of PGE₂ was assessed by enzyme-linked immunosorbent assay.

RESULTS

Esophageal mucosal injury in the group of EJA with H. pylori infection was decreased than that in EJA group (p < .05). The incidence of BE and EA in rats undergoing EJA with H. pylori infection was increased than in rats undergoing EJA with no statistical difference. Celecoxib treatment decreased the incidence of EA in rats undergoing EJA with H. pylori infection (p < .05). The expression of CDX2 mRNA was decreased in rats with H. pylori infection or treated with celecoxib than in the rats of pseudo-operation group (p < .05). When compared with those in rats of pseudo-operation group, the expression of COX-2 mRNA and the level of PGE₂ were upregulated in rats undergoing EJA irrespective of H. pylori infection (p < .05) and downregulated in rats treated with celecoxib (p < .05). When H. pylori colonized in esophagus, the severity of inflammation and the incidence of BE and EA were increased significantly. Higher levels of COX-2 expression and PGE₂ were detected in rats with esophageal H. pylori colonization.

CONCLUSIONS

When H. pylori infect in stomach, it may reduce the severity of inflammation. However, when colonizes in esophagus, H. pylori increases the severity of esophageal inflammation and the incidence of BE and EA. Celecoxib administration attenuates the incidence of EA by inhibiting COX-2 expression.

Expression of cyclooxygenase isoforms in ulcerated tissues of the nonglandular portion of the stomach in horses

OBJECTIVE

To characterize the expression of the cyclooxygenase (COX)-1 and COX-2 isoforms in naturally occurring ulcers of the nonglandular portion of the stomach in horses. SPECIMEN POPULATION: 38 specimens from ulcerated stomachs and 10 specimens from healthy stomachs.

PROCEDURES

Specimens were collected at an abbatoir; for each specimen of squamous gastric mucosa, 1 portion was fixed in neutral-buffered 10% formalin for immunohistochemical analysis and another was frozen at -70 degrees C for immunoblotting analysis. Immunoreactivity to 2 antibodies, MF241 (selective for COX-1) and MF243 (selective for COX-2), was evaluated by a veterinary pathologist using a scoring system. Expression of COX-1 and COX-2 was confirmed by use of immunoblotting analyses.

RESULTS

All specimens from healthy stomachs strongly expressed COX-1, whereas only 2 of 10 expressed COX-2. The expression of both isoforms varied greatly in the ulcerated mucosal specimens. Expression of COX-1 was significantly lower and expression of COX-2 was significantly higher in ulcerated versus healthy specimens.

CONCLUSIONS AND CLINICAL RELEVANCE

Increased expression of COX-2 in gastric ulcers of the squamous portion of the stomach in horses suggested a role for this enzyme in gastric ulcer healing.

Expression of COX-2 in stomach carcinogenesis

BACKGROUND

Gastric cancer is a frequent cause of cancer in Brazil. The understanding of gastric carcinogenesis is not completely known but the progress of the molecular biology has provided that the initiation and progression of gastric cancer process is a consequence of a cumulative series of multiple gene alterations.

AIM

The aim of the study is to investigate the relationship among cytoplasmatic COX-1 and COX-2, Bcl-2 and nuclear P53 in chronic gastritis, metaplasia, and intestinal and gastric cancer.

PATIENTS AND METHODS

COX-1, COX-2, P53, and Bcl-2 were evaluated by immunohistochemistry in 34 gastric adenocarcinoma (GA) tissues obtained from gastric resection, 21 tissues of patients with chronic gastritis (CG), and 34 with intestinal metaplasia (IM) obtained from endoscopic biopsies.

RESULTS

COX-1 and COX-2 were expressed in more than 85% of the tissues. A correlation between COX-1 and COX-2 were observed (r = 0.66). P53 was positive in 29% CG, 20% of IM and in 59 % of GA. Bcl-2 was negative in all the CG, in 88% of IM, and in 85% of GA. P53 staining was expressed more frequently in gastric cancer when compared to CG (p = 0.05) or IM (p = 0.003). The expression of Bcl-2 was also higher in gastric cancer (p = 0.002) and in intestinal metaplasia (p = 0.04) when compared to CG. There were no difference between metaplasia and chronic gastritis for P53 or Bcl-2. The immunoreactivity of COX-2 in gastric cancer was higher in the intestinal type (58%) than in diffuse type. A higher expression of COX-2 was found in advanced gastric cancer (p = 0.019). P53 was also more frequent in node positive cancer (p = 0.04).

CONCLUSION

COX-2 is probably involved in gastric carcinogenesis, being an early alteration in cancer. Although we observed in this study a correlation between COX-2 and depth of cancer, this association as a prognostic marker is not well defined. P53 and Bcl-2 was expressed mainly in gastric cancer, being probably a latest alteration in gastric development.

Effect and Mechanism of Lactobacillus on treating Mongolian Gerbil with Helicobacter pylori infectious gastritis

AIM: To evaluate the therapeutic efficacy of Bacillus acidi lactici for H pylori-related gastritis in clean grade Mongolian Gerbil model, and to explore its therapeutic mechanism.

METHODS: A total of 32 Mongolian Gerbil rats were infected with H pylori to establish the gastritis model, and then were randomly divided into 4 groups. Eight normal rats were taken as normal control group. The first group was treated with available trigeminy therapy, the second group Bacillus acidi lactici strains, the third group Bacillus acidi lactici plus PPI, and the fourth group sodium chloride solution for 10 d. Four weeks after the last treatment, the mice were all sacrificed. The infection of H pylori in gastric mucosa of the mice was detected using rapid urease test, Giemsa staining and culture. The histopathological changes in the gastric mucosa of mice were estimated using hematoxylin-eosin staining. Then protein expression of COX-2, IL-6 and TNF-α in gastric mucosa were examined using immunocytochemical staining assay.

RESULTS: Mongolian Gerbil model with H pylori infectious gastritis was successfully established. There was no significant difference in eradication of H pylori among the first, the second group and the third group. However, eradication rate in either of the first three groups was significantly lower than the fourth group (87.5%, 75%, 75% vs 100%, all P < 0.05). The chronic inflammatory response of the fourth group was more serious than the first, second and third group, especially in body of stomach (4.2 ± 1.06 vs 1.8 ± 0.54, 2.0 ± 0.48, 1.9 ± 0.50, all P < 0.05), sinus ventriculi (4.6 ± 0.74 vs 1.5 ± 0.27, 1.4 ± 0.33, 1.7 ± 0.46, all P < 0.05) and duodenum (4.1 ± 0.83 vs 1.4 ± 0.41, 1.7 ± 0.29, 1.6 ± 0.52, all P < 0.05). There was no significant difference between the first, second and third group in the chronic inflammatory response. At protein level, there was no IL-6 expression in the normal group, expressions of COX-2, IL-6, TNF-α in the first, the second and the third group were significantly decreased compared with the fourth group (COX-2: 3.57 ± 0.32, 3.89 ± 0.51, 2.95 ± 0.76 vs 6.79 ± 1.68, all P < 0.05; IL-6: 2.42 ± 0.60, 2.28 ± 0.71, 1.93 ± 0.52 vs 5.61 ± 0.28, all P < 0.05; TNF-α: 3.30 ± 0.52, 3.65 ± 0.35, 2.84 ± 0.20 vs 6.76 ± 1.63, all P < 0.05), but were significantly increased compared with the control group.

CONCLUSION: The therapy of Bacillus acidi lactici for H pylori-related gastritis was effective, equal to the available trigeminy therapy. Bacillus acidi lactici therapy for Helicobacter pylori-related gastritis decreases the expression of COX-2, IL-6 and TNF-α in gastric mucosa.