• Korean Journal of Clinical Laboratory Science
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• v.47 no.4
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• pp.161-167
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• 2015

These commensal intestinal bacteria can enhance the immune system and aid in nutrient absorption but can also act as opportunistic pathogens. Among these intestinal bacteria, the anaerobic Bacteroides fragilis are divided into enterotoxigenic B. fragilis (ETBF) which secrete the B. fragilis toxin (BFT) and non-enterotoxigenic B. fragilis (NTBF) which do not secrete BFT. ETBF can cause diarrhea and colitis in both humans and livestock but can also be found in asymptomatic individuals. ETBF is predominantly found in patients with inflammatory diarrheal diseases and traveller's diarrhea. Several clinical studies have also reported an increased prevalence of ETBF in human patients with inflammatory bowel disease (IBD), colitis and colorectal cancer. In small animal models (C57BL/6 wild-type mice, germ-free mice, multiple intestinal neoplasia (Min) mice, rabbits and Mongolian gerbils), ETBF have been found to initiate and/or aggravate IBD, colitis and colorectal cancer. BFT induces E-cadherin cleavage in intestinal epithelial cells resulting in loss of epithelial cell integrity. Subsequent activation of the ${\beta}$-catenin pathway leads to increased cellular proliferation. In addition, ETBF causes acute and chronic colitis in wild-type mice as well as enhances tumorigenesis in Min mice via activation of the Stat3/Th17 pathway. Currently, ETBF can be detected using a BFT toxin bioassay and by PCR. Advances in molecular biological techniques such as real-time PCR have allowed both researchers as well as clinicians to rapidly detect ETBF in clinical samples. The emergence of more sensitive techniques will likely advance molecular insight into the role of ETBF in colitis and cancer.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10b
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• pp.15-15
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• 2001

In the present study, we examined the chemopreventive effects of indole-3-carbinol (I3C), a constituent of cruciferous vegetables (the Family of Cruciferae) such as cabbages, cauliflowers and broccoli on multiple intestinal neoplasia (Min) genetic mouse model and on mouse colon carcinogenesis induced by azoxymethane (AOM) as well as on rat mammary carcinogenesis induced by 7, 12-dimethybenz［$\alpha$］anthracene (DMBA).(omitted)

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.58-58
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• 2001

In the present study, we examined the chemopreventive effects of indole-3-carbinol (I3C), a constituent of cruciferous vegetables (the Family of Cruciferae) such as cabbages, cauliflowers and broccoli on multiple intestinal neoplasia (Min) genetic mouse model and on mouse colon carcinogenesis induced by azoxymethane (AOM) as well as on rat mammary carcinogenesis induced by 7, 12-dimethybenz［$\alpha$］anthracene (DMBA).(omitted)

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.1983-1988
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• 2012

High temperature- and pressure-treated garlic (HTPG) has been shown to have enhanced antioxidative activity and polyphenol contents. Previously, we reported that HTPG inhibited 1,2-dimethylhydrazine-induced mucin depleted foci (premalignant lesions) and $O^6$-methylguanine DNA adduct formation in the rat colorectum. In the present study, we investigated the modifying effects of HTPG on N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG)-induced pyloric stomach and small intestinal carcinogenesis in mice. Male C57BL/6 mice were given ENNG (100 mg/l) in drinking water for the first 4 weeks, then a basal diet or diet containing 2% or 5% HTPG for 30 weeks. The incidence and multiplicity of pyloric stomach and small intestinal (duodenal and jejunal) tumors in the 2% HTPG group (but not in the 5% HTPG group) were significantly lower than those in the control group. Cell proliferation of normal-appearing duodenal mucosa was assessed by MIB-5 immunohistochemistry and shown to be significantly lower with 2% HTPG (but again not 5% HTPG) than in controls. These results in dicate that HTPG, at 2% in the diet, inhibited ENNG-induced pyloric stomach and small intestinal (especially duodenal) tumorigenesis in mice, associated with suppression of cell proliferation.

• Korean Journal of Bronchoesophagology
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• v.17 no.1
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• pp.23-28
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• 2011

Diagnosis of early esophageal cancer has become more frequent as a result of improved endoscopic technology, surveillance programmes, and increasing experience and awareness on the part of endoscopists. In early esophageal cancer, squamous cell carcinoma and early adenocarcinoma must be managed differently because they have different origins, pathogenesis. and clinical characteristics. The current treatment options vary widely, from extended resection with lymphadenectomy to endoscopic mucosal resection (EMR) or ablation. None of these treatment options can be recommended universally. Instead, an individualized strategy should be based on the depth of tumor infiltration into the mucosa or submucosa, the presence or absence of lymph node metastases, the multicentricity of tumor growth, the length of the segment of intestinal metaplasia, and comorbidities of the patient. EMR has become increasingly important, both as a diagnostic tool for the staging of esophageal carcinomas and as a method of carrying out definitive treatment when the cancer meets certain criteria in which the risk of lymph-node metastasis is negligible. EMR may be sufficient in a subset of patients who have m1 or m2 squamous cell carcinoma and in patients who have isolated foci of high-grade intraepithelial neoplasia or mucosal cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1115-1118
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• 2012

Diallyl sulfide (DAS), a flavoring compound derived from garlic, is considered to have cancer chemopreventive potential in experimental animals and humans. This study was designated to examine possible chemopreventive effects of DAS on colon carcinogenesis using genetically engineered transgenic $Apc^{Min/+}$ mice, a well-established animal model for familial adenomatous polyposis (FAP) and sporadic colorectal cancer. Male C57BL/6J-$Apc^{Min/+}$ mice were divided into three groups. Animals of group 1 were placed on the basal diet (AIN-76A) as non-treated controls. Animals of groups 2 and 3 were given DAS-containing diets (in doses of 100 and 300 ppm, respectively). All mice were sacrificed at the end of week 10 of the experiment. Histopathological investigation revealed that the incidence of colonic polyps was decreased dose-dependently by 19% (13/16) in group 2 and by 32% (13/20) in group 3 compared to the 100% incidence (10/10) in group 1. The multiplicity of colonic polyps per mouse was also slightly decreased by DAS treatment ($1.88{\pm}0.35$ in group 2 and $1.63{\pm}0.36$ in group 3) compared to $2.00{\pm}0.39$ in group 1. On the other hand, there were no significant differences in the numbers of total polyps per mouse in the small intestine between the groups. Taken together, we suggest that DAS may exert promising inhibitory effects on colon carcinogenesis in the transgenic $Apc^{Min/+}$ mice.

• Journal of Gastric Cancer
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• v.9 no.3
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• pp.78-87
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• 2009

Serum pepsinogen (sPG) is a marker of gastric mucosal atrophy, a condition that has been associated with an increased risk of gastric neoplasia. A low sPGI level and a low PG I/II ratio have been associated with severe gastric atrophy, and are frequently found in gastric cancer. Because the prevalence of gastric cancer is high in Korea, it would be convenient if a good biomarker for gastric cancer were developed. Two studies recently investigated the efficacy of sPG along with Helicobacter pylori (H. pylori) as a screening tool for gastric cancer. In these studies, sPG was measured using a Latex enhanced Turbidimetric Immunoassay. We found that H. pylori IgG status, age and gender were associated with serum pepsinogen levels. Thus, to increase the ability of the PG I/II ratio to detect atrophic gastritis, the cutoff value for the PG I/II ratio should be stratified according to the H. pylori IgG status. In addition, a PG I/II ratio ($\leq3.0$), which has been widely used as an international standard for gastric cancer, was found to be a reliable marker for the detection of gastric dysplasia or gastric cancer, especially of the intestinal type. The efficacy of the test in Korea was lower than the efficacy in Japan. However, the detecting power of a PG I/II ratio ($\leq3.0$) was significantly increased in the presence of H. pylori. The ratio together with H. pylori psotivitiy could provide a means of identifying persons at high risk of developing gastric cancer in Korea.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.5 no.1
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• pp.1-10
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• 2002

Purpose; Dysregulation of gastric epithelial cell proliferation and apoptosis are important in development of ulcer, atrophy and neoplasia in Helicobacter pylori (H. pylori) infection. The aim of this study was to investigate the effect of infection of H. pylori on gastric epithelial cell proliferation and apoptosis in children. Methods: Histological grading by updated Sydney system, PCNA immunostaining and TUNEL method were performed in H. pylori positive (N=58) and negative (N=40) gastric biopsy specimens. Results: In H. pylori positive children, there were significantly higher grade of polymorphonuclear neutrophil activity (P=0.000), chronic inflammation (P=0.000), epithelial damage (P=0.000) and lymphoid follicles (P=0.000) than in H. pylori negative children. Intestinal metaplasia was not seen in H. pylori positive children. PCNA index was significantly different between H. pylori positive children ($67.8{\pm}18.13$) and H. pylori negative children ($54.8{\pm}14.46$, P=0.000). There was positive correlation between PCNA index and H. pylori density (r=0.277, P=0.007), polymorphonuclear neutrophil activity (r=0.280, P=0.007) and chronic inflammation (r=0.284, P=0.006). Apoptosis index of H. pylori positive children ($0.44{\pm}0.447$) was significantly higher than of H. pylori negative children ($0.14{\pm}0.196$, P=0.000). There was positive correlation between apoptosis index and H. pylori density (r=0.472, P=0.000), polymorphonuclear neutrophil activity (r=0.370, P=0.001) and chronic inflammation (r=0.483, P=0.000). There was positive correlation between PCNA index and apoptosis index (r=0.353, P=0.003). Conclusion: The PCNA and apoptosis index in H. pylori positive children were significantly higher than in H. pylori negative children. This study suggested that gastric epithelial cell proliferation and apoptosis are important to pathogenesis of H. pylori infection in children.