Yusei Kanazawa

Enhanced Expression of Interleukin-8 and Activation of Nuclear Factor Kappa-B in Endoscopy-negative Gastroesophageal Reflux Disease

OBJECTIVE:Interleukin-8 (IL-8) mediates neutrophil trafficking via its receptors. Recent studies have shown that IL-8 is likely involved in the development and progression of erosive reflux esophagitis (RE), yet little is known about its implication in endoscopy-negative gastroesophageal reflux disease (GERD). The purpose of this study was to determine IL-8 messenger ribonucleic acid (mRNA) expression levels in endoscopy-negative GERD, along with assessment of nuclear factor kappaB (NF-κB) activation, which upregulates IL-8 expression.METHODS:We studied 31 patients with endoscopy-negative GERD, 15 patients with erosive RE, and 15 asymptomatic controls. Paired biopsy samples were taken from the esophagus 3 cm above the gastroesophageal junction; one biopsy was snap-frozen for measurement of IL-8 mRNA levels by real-time quantitative polymerase chain reaction, and another was formalin-fixed for histopathological evaluation. In nine endoscopy-negative GERD patients, the IL-8 mRNA expression levels were measured before and 8 wk after treatment with lansoprazole. We also sampled additional specimens for NF-κB-DNA binding assay and immunohistochemical analyses of NF-κB p65 and p50 subunits, IL-8 and specific IL-8 receptor, CXCR-1.RESULTS:The relative IL-8 mRNA expression levels were significantly higher in esophageal mucosa of patients with endoscopy-negative GERD than those of the controls. The presence of basal zone hyperplasia and intraepithelial neutrophils, histopathological hallmarks of GERD, were associated with higher levels of IL-8 mRNA. Lansoprazole treatment significantly reduced the IL-8 mRNA expression levels. The esophageal epithelium of patients with GERD showed intense immunoreactivity for IL-8, and expressed CXCR-1 antigen. We found NF-κB activation in esophageal mucosa in GERD patients and the NF-κB subunits were localized predominantly in the nuclei of IL-8-expressing cells.CONCLUSIONS:Our results demonstrate enhanced mucosal expression of IL-8 in incipient GERD even without mucosal breaks. NF-κB activation may be implicated in the pathogenesis in GERD.

Expression of heat shock protein (Hsp) 70 and Hsp 40 in gastric cancer

Heat shock proteins (Hsp) 70 and Hsp 40 are stress proteins that cooperate as chaperones in mammalian cells. We determined the expression of Hsp 70 and Hsp 40 in 81 gastric cancers. Immunoreactivities to Hsp 70 and Hsp 40 were detected in 67.9 and 22.2% of tumors, respectively. Immunohistochemical analysis showed enhanced Hsp 70 and Hsp 40 expression in gastric tumor tissue, relative to the surrounding normal tissue. Overexpression of Hsp 70 and Hsp 40 was also confirmed by immunoblotting. Among various clinicopathological parameters, low histopathological differentiation was associated with reduced expression of both proteins.

Pleiotropic Effects of Proton Pump Inhibitors Guest Editor: Yuji Naito Immune and Inflammatory Responses in GERD and Lansoprazole

The exact pathophysiological mechanisms responsible for gastroesophageal reflux disease (GERD) remain unclear. Recent studies have shown that mucosal immune and inflammatory responses, characterized by specific cytokine and chemokine profiles, may underlie the diverse esophageal phenotypes of GERD. Interleukin 8 (IL-8), a representative chemokine, mediates neutrophil trafficking via its receptors, mainly CXCR-1. The IL-8 mRNA and protein levels are increased in the esophageal mucosa, not only in reflux esophagitis (RE), but also in endoscopy-negative GERD (NERD), through activation of nuclear factor-κB (NF-κB), which is a pivotal transcription factor. Mucosal IL-8 concentrations have been found to parallel the endoscopic severity of RE, implying that this cytokine is a key player in the development of GERD. The mucosal levels of the C-C chemokines, macrophage chemoattractant protein 1 (MCP-1) and regulated on activation normal T-cell-expressed and presumably secreted (RANTES), which primarily attract monocytes and lymphocytes to the site of inflammation, respectively, are also elevated in RE. The secreted levels of IL-8 and IL-1β, a prototype of proinflammatory cytokine, are maximal at the proximal segment within Barrett esophagus (BE) tissue. The expression of the two pleiotrophic proinflammatory cytokines, IL-6 and tumor necrosis factor α, is enhanced in the intestinal epithelium of BE, which places this epithelium at a higher risk for developing malignancy. BE is characterized by a distinct Th-2 predominant cytokine profile (IL-4 and -10), compared to the proinflammatory nature of RE (interferone-γ). Treatment with a proton pump inhibitor, lansoprazole reduces the mucosal levels of IL-8 mRNA and protein in GERD, including RE and NERD. This may occur in part through an anti-inflammatory action of proton pump inhibitors beyond gastric acid inhibition.

Expression of heat shock protein (Hsp) 70 and Hsp 40 in colorectal cancer

Heat shock protein (Hsp) 70 and Hsp 40 are stress proteins that cooperate as chaperones in mammalian cells. The present study was designed to determine the expression levels of Hsp 70 and Hsp 40 in colorectal cancer by immunohistochemistry and Western blot analysis. Among 50 colorectal cancer tissues studied, 80% and 14% of tumors showed specific immunoreactivity to Hsp 70 and Hsp 40, respectively. Hsp 70 and Hsp 40 were overexpressed in cancer tissue samples compared with normal tissues, on both analytic sets. However, there were no significant correlations between their expression and various clinicopathological parameters of colorectal cancer. Hsp 70 and Hsp 40 may be tumor markers for colorectal cancer.

Immune thrombocytopenic purpura in patients with ulcerative colitis.

Extraintestinal manifestations of ulcerative colitis (UC) are well known, but immunologically mediated hematological diseases are relatively rare. We describe two cases of immune thrombocytopenic purpura (ITP) associated with preexisting UC. Our patients had typical symptoms of UC, and endoscopy showed pancolitis. During treatment with 5-aminosalicylic acid and steroids, severe thrombocytopenia was noted. ITP was diagnosed based on a normal to high number of megakaryocytes in the bone marrow, positive autoantibody to platelet membrane antigen, and absence of splenomegaly. Medical treatment, including increased dosage of steroids, failed to control UC and ITP in both patients. In the first patient, the platelet count recovered after colectomy, while the second patient died of a cerebral hemorrhage. We stress that a diagnosis of ITP should be considered for thrombocytopenia in patients with UC, especially those showing extensive and significant colonic inflammation, and that colectomy of UC might resolve resistant ITP.

Pseudoxanthoma elasticum with recurrent gastric hemorrhage managed by endoscopic mechanical hemostasis

A 24‐year‐old‐woman was admitted to our hospital for further examination of recurrent upper gastrointestinal tract hemorrhage. The characteristic xanthomatous papular rash, retinal angioid streaks, and stenosis of cardiac coronary artery confirmed the diagnosis of pseudoxanthoma elasticum. Upper gastrointestinal endoscopy revealed vascular dilation in the gastric body to fornix. The vessel showing conspicuous dilation covered with the discolored mucosa was suspected as the source of the bleeding. The vessel was identified as a dilated vein located in the submucosa by endoscopic ultrasonography and pulsed‐wave Doppler ultrasonography. Abdominal angiography demonstrated aneurysmal dilation in the splenic artery, but not in the gastric artery. Endoscopic band ligation was chosen as an initial treatment for the prevention of recurrent bleeding. The procedure seemed to be successful, but rebleeding occurred on the next day, which was again treated with hemostatic clipping. There have been no further episodes of gastrointestinal hemorrhage during the 15‐month follow up.