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Human diplogonoporiasis caused by the tapeworm Diplogonoporus balaenopterae has been rarely reported in Japan in the last decade. A 38-year-old man complained of a fever, diarrhea, intermittent abdominal pain, and worm excretion. He had a history of consuming raw juvenile Japanese anchovy one month earlier. On admission, the patient had acute enteritis and received intravenous fluids. During hospitalization, he excreted a white worm in his stool. On a macroscopic examination, the worm was found to be a tapeworm with scolexes. His health improved spontaneously without taking anthelmintic agents. Based on the genetic analysis, the tapeworm was identified as Diplogonoporus balaenopterae.

We investigated γ-H2AX formation, a biomarker of DNA damage, and expression of stem cell markers (SCMs), including cytokeratin 14, aldehyde dehydrogenase 1A1 (ALDH1A1), and CD44, in the development of rat bladder tumors induced by short-term administration of N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN). Histopathological examination showed that diffuse simple hyperplasia of the bladder urothelium induced by BBN recovered to the normal-appearing urothelium after withdrawal, whereas focal proliferative lesions were newly developed and subsequently progressed to benign papilloma and carcinoma. Immunohistochemical analysis revealed that BBN-induced γ-H2AX formation and ALDH1A1 and CD44 expression persisted at higher levels in the normal-appearing urothelium than those in the control group for long periods after withdrawal. Since persistent chronic inflammation was observed even after withdrawal, targeted gene expression analysis of inflammation-related factors revealed 101 genes, including Stat3 and Myc, that showed persistent high expression. Pathway analysis suggested that Stat3 and/or Myc activation may be associated with SCM expression. We focused on hepatocyte growth factor (Hgf), one of the genes predicted in relation to Stat3/Myc, and confirmed that HGF-positive cells increased by BBN persisted in the normal-appearing urothelium after withdrawal and colocalized with γ-H2AX and SCMs. These results suggested that the long-term persistence of γ-H2AX formation and SCM expression, which occurred during the early stages of bladder tumorigenesis, is not a transient response to exposure and might contribute to bladder tumorigenesis. Although further studies are needed, BBN-induced rat bladder tumors may originate from focal hyperplasia arising from SCM-positive cells via activation of the STAT3/MYC pathway after DNA damage involving γ-H2AX formation., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Bone marrow mesenchymal stem cells (MSCs) are critical regulators of postnatal bone homeostasis. Osteoporosis is characterized by bone volume and strength deterioration, partly due to MSC dysfunction. Cyclin-dependent kinase 8 (CDK8) belongs to the transcription-related CDK family. Here, CDK8 in MSCs was identified as important for bone homeostasis. CDK8 level was increased in aged MSCs along with the association with aging-related signals. Mouse genetic studies revealed that CDK8 in MSCs plays a crucial role in bone resorption and homeostasis. Mechanistically, CDK8 in MSCs extrinsically controls osteoclastogenesis through the signal transducer and transcription 1 (STAT1)-receptor activator of the nuclear factor κ Β ligand (RANKL) axis. Moreover, aged MSCs have high osteoclastogenesis-supporting activity, partly through a CDK8-dependent manner. Finally, pharmacological inhibition of CDK8 effectively repressed MSC-dependent osteoclastogenesis and prevented ovariectomy-induced osteoclastic activation and bone loss. These findings highlight that the CDK8-STAT1-RANKL axis in MSCs could play a crucial role in bone resorption and homeostasis., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Extracellular signal-regulated kinase 5 (Erk5) belongs to the mitogen-activated protein kinase (MAPK) family. Previously, we demonstrated that Erk5 directly phosphorylates Smad-specific E3 ubiquitin protein ligase 2 (Smurf2) at Thr249 (Smurf2Thr249) to activate its E3 ubiquitin ligase activity. Although we have clarified the importance of Erk5 in embryonic mesenchymal stem cells (MSCs) on skeletogenesis, its role in adult bone marrow (BM)-MSCs on bone homeostasis remains unknown. Leptin receptor-positive (LepR+) BM-MSCs represent a major source of bone in adult bone marrow and are critical regulators of postnatal bone homeostasis. Here, we identified Erk5 in BM-MSCs as an important regulator of bone homeostasis in adulthood. Bone marrow tissue was progressively osteosclerotic in mice lacking Erk5 in LepR+ BM-MSCs with age, accompanied by increased bone formation and normal bone resorption in vivo. Erk5 deficiency increased the osteogenic differentiation of BM-MSCs along with a higher expression of Runx2 and Osterix, essential transcription factors for osteogenic differentiation, without affecting their stemness in vitro. Erk5 deficiency decreased Smurf2Thr249 phosphorylation and subsequently increased Smad1/5/8-dependent signaling in BM-MSCs. The genetic introduction of the Smurf2T249E mutant (a phosphomimetic mutant) suppressed the osteosclerotic phenotype in Erk5-deficient mice. These findings suggest that the Erk5-Smurf2Thr249 axis in BM-MSCs plays a critical role in the maintenance of proper bone homeostasis by preventing excessive osteogenesis in adult bone marrow., (© The Author(s) 2022. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

For gastric lesions in a patient with a history of breast cancer, it is essential to distinguish between primary gastric cancer and gastric metastasis from breast cancer. However, gastric metastasis from breast cancer often mimics primary linitis plastica, and histological diagnosis may be difficult with conventional endoscopic biopsies. Herein, we describe the case of a 75-year-old woman who presented at our hospital with epigastralgia and vomiting. She had a history of mastectomy for carcinoma of the right breast and had received hormone therapy as adjuvant therapy. Computed tomography at arrival showed thickening of the gastric wall at the antrum and peritoneal dissemination. Esophagogastroduodenoscopy showed mucosal swelling of the antrum and stenosis of the pylorus, and histological diagnosis failed with conventional endoscopic biopsies. Endoscopic ultrasound-guided fine-needle biopsy using a Franseen needle was performed, and a diagnosis of gastric metastasis from breast cancer was made. She received hormone therapy and chemotherapy after deployment of a metallic stent for gastric outlet obstruction. To the best of our knowledge, this is the first case of gastric metastasis from breast cancer diagnosed using endoscopic ultrasound-guided fine-needle biopsy., Competing Interests: The authors declare no conflicts of interest., (© 2022 The Authors. DEN Open published by John Wiley & Sons Australia, Ltd on behalf of Japan Gastroenterological Endoscopy Society.)

A 92-year-old woman with gallstone pancreatitis and acute cholangitis was admitted to our hospital where endoscopic retrograde cholangiopancreatography was performed for emergency biliary drainage. Biliary cannulation was unsuccessful. Consequently, percutaneous transhepatic gallbladder drainage (PTGBD) was performed, and her symptoms improved. The PTGBD tube was removed by the patient on the third day of admission resulting in cardiopulmonary arrest two hours later. Cardiopulmonary resuscitation restored spontaneous circulation. Contrast computed tomography revealed intra-abdominal hemorrhage from the right hepatic artery by the removed part of the PTGBD tube. The patient died despite hemostasis by transcatheter artery embolization. PTGBD is generally effective and safe;however, it can cause fatal hemorrhage, especially if PTGBD tubes are removed by the patient. Thus, self-removal should be strictly prevented.

1,3-Dichloro-2-propanol (1,3-DCP), a food contaminant, exerts carcinogenic effects in multiple organs, including the liver and kidneys, in rats. However, the underlying mechanisms of 1,3-DCP-induced carcinogenesis remain unclear. Here, the in vivo mutagenicity and tumor-promoting activity of 1,3-DCP in the liver and kidneys were evaluated using medium-term gpt delta rat models previously established in our laboratory (GPG and GNP models). Six-week-old male F344 gpt delta rats were treated with 0 or 50 mg/kg body weight/day 1,3-DCP by gavage for 4 weeks. After 2 weeks of cessation, partial hepatectomy or unilateral nephrectomy was performed to collect samples for in vivo mutation assays, followed by single administration of diethylnitrosamine (DEN) for tumor initiation. One week after DEN injection, 1,3-DCP treatment was resumed, and tumor-promoting activity was evaluated in the residual liver or kidneys by histopathological analysis of preneoplastic lesions. gpt mutant frequencies increased in excised liver and kidney tissues following 1,3-DCP treatment. 1,3-DCP did not affect the development of glutathione S-transferase placental form-positive foci in residual liver tissues, but enhanced atypical tubule hyperplasia in residual kidney tissues. Detailed histopathological analyses revealed glomerular injury and increased cell proliferation of renal tubular cells in residual kidney tissues of rats treated with 1,3-DCP. These results suggested possible involvement of genotoxic mechanisms in 1,3-DCP-induced carcinogenesis in the liver and kidneys. In addition, we found that 1,3-DCP exhibited limited tumor-promoting activity in the liver, but enhanced clonal expansion in renal carcinogenesis via proliferation of renal tubular cells following glomerular injury., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objectives: Post-ERCP pancreatitis (PEP) after self-expandable metallic stent (SEMS) insertion across the papilla of Vater is an important adverse event that affects the patient's quality of life (QOL). We examined the predictive factors of PEP after SEMS insertion to treat obstructive jaundice due to malignancy., Methods: Ninety patients who underwent biliary SEMS insertion for biliary obstruction due to malignancy at Iwata City Hospital between 2010 and 2018 were reviewed. We evaluated the relationship between the incidence of PEP after biliary SEMS insertion and clinical factors. We measured the thickness of the pancreatic parenchyma and diameter of the main pancreatic duct (MPD) at the left side of the corpus vertebrae., Results: Mild and severe PEP were diagnosed in 10 (11.1%) and 1 (1.1%) patients, respectively. Only the thickness of the pancreatic parenchyma and diameter of MPD significantly differed between the PEP and non-PEP groups. The incidence of PEP among patients whose thickness of the pancreatic parenchyma at the left side of the corpus vertebrae was less than 9.5 mm (0%) on computed tomography was lower than that in patients whose thickness was 9.5 mm or greater (34.4%). Similarly, a wider (5 mm or more) diameter of MPD (4.3%) reduced the incidence of PEP compared with a narrower diameter (40.0%). Logistic regression analysis revealed that the probability of PEP decreases 3.91 times for every 1-mm increase in MPD diameter (95% CI 1.23-12.4, p  = .02)., Conclusion: Based on our study, a dilated MPD is a negative predictive factor of pancreatitis related to biliary SEMS insertion.

Glioblastoma (GBM) is the most malignant form of glioma. Glioma stem cells (GSCs) contribute to the initiation, progression, and recurrence of GBM as a result of their self-renewal potential and tumorigenicity. Cyclin-dependent kinase 8 (CDK8) belongs to the transcription-related CDK family. Although CDK8 has been shown to be implicated in the malignancy of several types of cancer, its functional role and mechanism in gliomagenesis remain largely unknown. Here, we demonstrate how CDK8 plays an essential role in maintaining stemness and tumorigenicity in GSCs. The genetic inhibition of CDK8 by shRNA or CRISPR interference resulted in an abrogation of the self-renewal potential and tumorigenicity of patient-derived GSCs, which could be significantly rescued by the ectopic expression of c-MYC, a stem cell transcription factor. Moreover, we demonstrated that the pharmacological inhibition of CDK8 significantly attenuated the self-renewal potential and tumorigenicity of GSCs. CDK8 expression was significantly higher in human GBM tissues than in normal brain tissues, and its expression was positively correlated with stem cell markers including c-MYC and SOX2 in human GBM specimens. Additionally, CDK8 expression is associated with poor survival in GBM patients. Collectively, these findings highlight the importance of the CDK8-c-MYC axis in maintaining stemness and tumorigenicity in GSCs; these findings also identify the CDK8-c-MYC axis as a potential target for GSC-directed therapy.

Monocyclic aromatic amines, o -toluidine ( o -Tol) and its structural analog o -anisidine ( o -Ans), are IARC Group 1 and Group 2A urinary bladder carcinogens, respectively, and are involved in metabolic activation and DNA damage. Our recent study revealed that 2-methyl- N 4 -(2-methylphenyl) benzene-1,4-diamine (MMBD), a p -semidine-type homodimer of o -Tol, was detected and identified in an in vitro reaction of o -Tol with S9 mix and in vivo urinary samples of o -Tol-exposed rats. Potent mutagenic, genotoxic, and cytotoxic activities were reported with MMBD, suggesting its involvement in urinary bladder carcinogenesis. However, it remains unknown whether o -Ans is converted to active metabolites to induce DNA damage in a similar manner as o -Tol. In this study, we report that a novel o -Ans metabolite, 2-methoxy- N 4 -(2-methoxyphenyl) benzene-1,4-diamine (MxMxBD), a dimer by head-to-tail binding ( p -semidine form), was for the first time identified in o -Ans-exposed rat urine. MxMxBD induced a stronger mutagenicity in N -acetyltransferase overexpressed Salmonella typhimurium strains and potent genotoxicity and cytotoxicity in human bladder carcinoma T24 cells compared with o -Ans. These results suggest that MxMxBD may to some extent contribute toward urinary bladder carcinogenesis. In addition to homodimerization, such as MxMxBD, heterodimerizations were observed when o -Ans was coincubated with o -Tol or aniline (Ani) in in vitro reactions with S9 mix. This study highlights the important consideration of homodimerizations and heterodimerizations of monocyclic aromatic amines, including o -Ans, o -Tol, and Ani, in the evaluation of the combined exposure risk of bladder carcinogenesis.

We previously demonstrated that immunohistochemistry for γ-H2AX, a biomarker of DNA damage, is useful for early detection of urinary bladder carcinogens in rats. In a 28-day repeated-dose study, γ-H2AX was shown to have high sensitivity for detection of bladder carcinogens. However, no reports have evaluated whether a combination of multiple biomarkers may further improve sensitivity. Accordingly, in this study, we aimed to evaluate the applicability of bladder tissue and cancer stem cell markers, including cytokeratin 14 (KRT14), aldehyde dehydrogenase 1A1 (ALDH1A1), and cluster of differentiation 44 (CD44), as complementary markers for early detection of bladder carcinogens. Bladder samples obtained from male F344 rats orally treated with 14 bladder carcinogens and five nonbladder carcinogens for 28 days were used for immunohistochemical analysis of stem cell markers. In the bladder carcinogen-treated rats, increases in KRT14, ALDH1A1, and CD44 expression were observed in 9, 10, and 10 out of 14 groups, respectively, whereas the five nonbladder carcinogens did not cause upregulation of these markers. Although most epithelial cells with KRT14 or ALDH1A1 expression were also positive for CD44, KRT14 and ALDH1A1 expression were mutually exclusive. Twelve bladder carcinogens showed increases in at least one of the three markers, indicating that the combined evaluation showed higher sensitivity than the use of individual markers alone. Importantly, two of three bladder carcinogens that did not induce γ-H2AX immunostaining showed stem cell marker expression. Our results demonstrated that these stem cell markers may be useful as complementary markers for γ-H2AX in evaluation of bladder carcinogens.

Although aromatic amines are widely used as raw materials for dyes, some of them have been concerned about carcinogenicity in the urinary bladder. We examined early changes in histopathology and the formation of γ-H2AX, a biomarker of DNA damage, in the urinary bladder of rats to investigate the mechanisms of mucosal damage induced by monocyclic aromatic amines. 6-week-old male F344 rats were administered 0.4% or 0.8% o-toluidine, 0.3% or 1.0% o-anisidine, 0.4% 2,4-xylidine, 0.2% p-toluidine, or 0.6% aniline in the diet for 4 weeks. Animals were sequentially killed from day 2 to after 2 weeks of recovery, and histopathological and immunohistochemical analyses were performed. In the 0.8% o-toluidine group, there was sequential progression of bladder lesions, characterized by edematous changes and intramucosal hemorrhage at day 2 and formation of granulation tissue with mononuclear cell infiltration at week 1, followed by diffuse hyperplasia at weeks 2 and 4. In the 1.0% o-anisidine group, simple hyperplasia only with slight inflammation was detected from week 1. Whereas γ-H2AX-positive bladder epithelial cells in the 1.0% o-anisidine group were significantly increased in a time-dependent manner, transient increases in γ-H2AX-positive cells were detected at day 2 and week 1 in the 0.8% o-toluidine group. No apparent bladder lesions or increases in γ-H2AX formation were observed in any other groups. These results revealed different mechanisms of bladder mucosal damage associated with o-toluidine and o-anisidine. Moreover, immunohistochemical analysis for γ-H2AX suggested that both compounds may induce DNA damage in epithelial cells, mainly basal cells, of the bladder mucosa.

A 37-year-old woman exhibited abnormal liver enzyme levels without any symptoms at a medical check-up. She was born and raised in Hubei, China, and had immigrated to Japan in her mid-thirties. Ultrasonography revealed an enlarged caudate lobe of the liver and a wide moniliform portal vein, whereas computed tomography revealed lined calcification on the surface of the liver and on the collateral vein of the portal vein. Although imaging studies provided no critical findings, the crucial information that led to diagnosis was gained through the interview with the patient. Schistosomiasis japonica was known to be prevalent in her hometown, and she reported that her father's past infection was due to Schistosoma japonicum. Serological analysis demonstrated high levels of anti-S. japonicum antibodies, which were reduced using praziquantel administration.

Cervical inlet patch (CIP), also referred to as esophageal heterotopic gastric mucosa, is regarded as the residue of columnar epithelium of the embryonic esophagus. Narrow band imaging increases the detection rate of CIP. Herein, we present a 55-year-old man with symptomatic circumferential inlet patch. He exhibited globus and dysphagia, and esophagogastroduodenoscopy found cir-cumferential CIP, where im-munohistochemistry revealed the existence of pro-ton pumps (H + , K + -ATPase). His throat symptoms were relieved by acid suppressive therapy with pump inhibitors. This case indicated that CIP should be considered as a differential diagnosis for the cause of globus symptoms in rare cases., Competing Interests: Conflict-of-interest statement: No conflict interest to declare.

An asymptomatic pancreatic tumor was discovered in a 77-year-old man during a medical check-up. An abdominal computed tomography (CT) and magnetic resonance imaging (MRI) revealed a cystic mass containing a septum-like solid portion in the head of the pancreas, measuring 3.5cm in diameter. Additionally, abdominal contrast-enhanced ultrasonography (US) revealed increased flow in the solid portion and a tumor capsule in its early phase. We preoperatively diagnosed the lesion as a cystic-degenerated pancreatic neuroendocrine tumor or solid-pseudopapillary tumor and performed a pancreatoduodenectomy. Histopathological examination revealed a cystic pancreatic mass consisting of spindle-shaped cells, with S-100-positive and SMA-negative immunohistochemical stainings. This lesion was diagnosed as a pancreatic schwannoma from these findings.

Guggulsterone is a plant sterol derived from gum resin of Commiphora wightii. The gum resin from guggul plants has been used for thousand years in Ayurveda to treat various disorders, including internal tumors, obesity, liver disorders, malignant sores and ulcers, urinary complaints, intestinal worms, leucoderma, sinuses, edema, and sudden paralytic seizures. Guggulsterone has been identified a bioactive components of this gum resin. This plant steroid has been reported to work as an antagonist of certain nuclear receptors, especially farnesoid X receptor, which regulates bile acids and cholesterol metabolism. Guggulsterone also mediates gene expression through the regulation of transcription factors, including nuclear factor-kappa B and signal transducer and activator of transcription 3, which plays important roles in the development of inflammation and tumorigenesis. Guggulsterone has been shown to downregulate the expression of proteins involved in anti-apoptotic, cell survival, cell proliferation, angiogenic, metastatic, and chemoresistant activities in tumor cells. This review aimed to clarify the cell signal pathways targeted by guggulsterone and the bioactivities of guggulsterone in animal models and humans.

Helicobacter pylori (H. pylori) infection is well known to be associated with chronic gastritis and also development of gastric cancer. Raphanobrassica (RB) is an intergeneric hybrid of the genera Raphanus (radish) and Brassica (cabbages) containing appreciable amounts of glucoraphanin (GR) and glucoraphenin (GRe), which are actively hydrolyzed by the enzyme myrosinase to sulforaphane and sulforaphene, respectively. Both of these metabolites exert antimicrobial and anti-inflammatory activity. The purpose of the present study was to investigate the effect of two freeze-dried products of RB (RB1 and RB2) on H. pylori-induced gastritis in Mongolian gerbils. Six-week-old male Mongolian gerbils were inoculated orally with H. pylori (ATCC 43504), and 2weeks later were fed diets containing no additives or diets supplemented with 2% RB1 (containing both GR and GRe) or 2% RB2 (containing GR only) for 10weeks. In the RB1, but not the RB2 group, mononuclear cell infiltration, mRNA expression of IL-6, and cell proliferation in the gastric mucosa were significantly suppressed. These results indicate that RB1 containing both GR and GRe exerted significant inhibitory effects on H. pylori-induced gastritis in Mongolian gerbils apparently mediated via suppression of IL-6 expression and chronic inflammation., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Background: Trinitrobenzenesulfonic acid (TNBS)-induced colitis is one of the most widely used experimental colitis models. However, there is no standard procedure for inducing colitis by TNBS because it is difficult to achieve a uniform distribution of colitis. We have developed a modified method of murine TNBS-induced colitis that involves inhalation anesthesia with sevoflurane combined with both single and repeated TNBS administrations., Aims: To compare the usefulness of our newly developed method for inducing murine TNBS-induced colitis with that of conventional intraperitoneal anesthesia., Methods: TNBS in ethanol was administered to C57BL/6J mice held in an inverted vertical position either under continuous inhalation anesthesia with sevoflurane, in accordance with our newly developed method, or by intraperitoneal injection with 2.5 % avertin, in accordance with the conventional procedure. Body weight change, cytokine profile, and histological findings were examined during the course of colitis., Results: The dispersion of anesthesia time, TNBS retention time, and nadir weight during the course of colitis was decreased using the newly developed method compared with the conventional procedure. Optimization of the modified TNBS-induced colitis, as evidenced by the predominant expression of Th1 and Th17 cytokines on day 7, was attained by the injection of 2.25 mg TNBS in 55 % ethanol. Regulation of the TNBS retention time using inhalation anesthesia with sevoflurane allowed strict control of the disease severity of TNBS-induced colitis. Using the modified method we were also able to develop a chronic TNBS-induced colitis model by repeated TNBS administration without excessive mortality of the mice., Conclusions: Our modified method for murine TNBS-induced colitis using continuous inhalation anesthesia with sevoflurane provides a better experimental colitis model following both single and repeated TNBS administrations.

Diphenylarsinic acid (DPAA), a chemical warfare-related neurotoxic organic arsenical, is present in the groundwater and soil in some regions of Japan due to illegal dumping after World War II. Inorganic arsenic is carcinogenic in humans and its organic arsenic metabolites are carcinogenic in animal studies, raising serious concerns about the carcinogenicity of DPAA. However, the carcinogenic potential of DPAA has not yet been evaluated. In the present study we found that DPAA significantly enhanced the development of diethylnitrosamine-induced preneoplastic lesions in the liver in a medium-term rat liver carcinogenesis assay. Evaluation of the expression of cytochrome P450 (CYP) enzymes in the liver revealed that DPAA induced the expression of CYP1B1, but not any other CYP1, CYP2, or CYP3 enzymes, suggesting that CYP1B1 might be the enzyme responsible for the metabolic activation of DPAA. We also found increased oxidative DNA damage, possibly due to elevated CYP1B1 expression. Induction of CYP1B1 has generally been linked with the activation of AhR, and we found that DPAA activates the aryl hydrocarbon receptor (AhR). Importantly, the promotion effect of DPAA was observed only at a dose that activated the AhR, suggesting that activation of AhR and consequent induction of AhR target genes and oxidative DNA damage plays a vital role in the promotion effects of DPAA. The present study provides, for the first time, evidence regarding the carcinogenicity of DPAA and indicates the necessity of comprehensive evaluation of its carcinogenic potential using long-term carcinogenicity studies., (© 2013.)

Statins, inhibitors of the enzyme 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, are known not only as cholesterol-lowering agents but also as anti-inflammatory mediators. However, their regulatory effect on intestinal mucosal immunity remains unclear. The present study examined the possible direct effects of statin on intestinal intraepithelial lymphocytes (IELs), the front line cells of the intestinal mucosal immune system. Murine IELs were isolated from the small intestines of C57BL/6 mice. IELs activated with anti-CD3/CD28 monoclonal antibodies produced interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-2, and IL-4 in significant numbers; however, they did not produce IL-5. Both simvastatin and lovastatin suppressed IEL production of IFN-γ, TNF-α, IL-2, and IL-4 in a dose-dependent manner, whereas 48-h treatment with high concentrations (5 × 10(-5)M) of simvastatin and lovastatin did not affect the number of IELs. The suppressive effect of the simvastatin was significantly restored by the addition of mevalonate, farnesyl pyrophosphate ammonium salt, and geranylgeranyl pyrophosphate ammonium salt, which are downstream metabolites of HMG-CoA. These findings suggest that statins have direct suppressive effects on the production of T helper 1-cytokines and IL-4 in IELs; these effects are associated with inhibition of the mevalonate pathway to some extent., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Background & Aims: Low doses of aspirin can injure the gastric mucosa. It is not clear whether other drugs such as the antiplatelet agent clopidogrel also cause gastric mucosal injury or exacerbate aspirin-induced injury, or whether proton pump inhibitors prevent damage., Methods: Twenty Japanese subjects with different CYP2C19 genotypes were randomly assigned to groups that were given a low dose of aspirin (100 mg; A), clopidogrel (75 mg; C), low dose of aspirin and clopidogrel (AC), or low dose of aspirin in combination with clopidogrel and rabeprazole (10 mg; ACR) once daily for 7 days. Subjects underwent gastroduodenoscopy and platelet tests on days 3 and 7; gastric mucosal damage was assessed by using the modified Lanza score (MLS). We performed 24-hour intragastric pH monitoring on day 7 of each regimen. We also analyzed the effects of the AC regimen on 30 patients with different CYP2C19 genotypes., Results: Subjects in groups A, C, and AC had significantly higher levels of gastric mucosal damage on days 3 and 7, compared with baseline. The median MLS for the AC group was similar to that of the A group. Helicobacter pylori-negative subjects in the ACR group with different CYP2C19 genotypes had significant differences in MLS, intragastric pH, and platelet function. Gastric mucosal injury was inhibited equally among H pylori-positive subjects in the ACR group. Rabeprazole did not appear to affect platelet function or intragastric pH in subjects given clopidogrel., Conclusions: Clopidogrel and low doses of aspirin cause a similar degree of gastric mucosal damage. Rabeprazole prevented this damage without reducing the antiplatelet function of clopidogrel. However, its prophylactic effect varies with CYP2C19 genotype in H pylori-negative subjects., (Copyright © 2012 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Extranodal natural killer (NK)/T-cell lymphoma, nasal type, exhibits aggressive tumor behavior and carries a poor prognosis. Recently, lymphomatoid gastropathy with NK/T cell infiltration into gastric mucosa has been recognized as a pseudo-malignant disease which regresses without treatment. Because the conventional immunohistochemical criteria of lymphomatoid gastropathy is similar to that of extranodal NK/T-cell lymphoma nasal type, it is difficult to distinguish between the two conditions by histopathological evaluation only. Here, we report a rare case of lymphomatoid gastropathy in a 57-year-old female. Gastroendoscopy on routine check-up revealed elevated reddish lesions < 1 cm in diameter in the gastric fornix and body. Although repeat endoscopies at 1 and 6 mo later revealed no gastric lesions at any locations without any treatments, at 12 mo later gastric lymphomatoid lesions recurred at gastric fornix and body. Histological examination of endoscopic biopsy specimens at 12 mo showed atypical NK cell infiltration with CD3⁺, CD4⁻, CD5⁻, CD7⁺, CD8⁻, CD20⁻, CD30⁻, CD56⁺, CD79a⁻ and T-cell-restricted intracellular antigen-1⁺ into gastric mucosa. After treatment for Helicobacter pylori (H. pylori) eradication, the lesions disappeared in all locations of the gastric fornix and body over the subsequent 12 mo. Here, we report a case of H. pylori-positive lymphomatoid gastropathy with massive NK-cell proliferation, and also review the literature concerning newly identified lymphomatoid gastropathy based on comparison of extra nodal NK/T-cell lymphoma nasal type. In any case, these lesions are evaluated with biopsy specimens, the possibility of this benign entity should be considered, and excessive treatment should be carefully avoided. Close follow-up for this case of lymphomatoid gastropathy is necessary to exclude any underlying malignancy.

We examined whether norepinephrine (NE) had direct effects on cytokine production by murine intestinal intraepithelial lymphocytes (IELs), compared with splenocytes. CD3⁺ IELs and CD3⁺ splenocytes expressed α(1B), α(1D), α(2C), β₁, β₂, and β₃ adrenoceptors (ARs). NE significantly suppressed IFN-γ and TNF-α production by IELs and splenocytes ex vivo. The suppressive effects of NE in IELs were reversed by β₁ AR antagonist CGP-20712A, whereas those in splenocytes were reversed by β₂ AR antagonist ICI118,551. In IELs, β₁ AR agonist xamoterol mimicked the suppressive effects of NE. These results indicated NE regulates intestinal mucosal immune responses mediated by IELs via β₁ AR., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Aim: We investigated the effects of trastuzumab, an anti-HER2 humanized monoclonal antibody, on DNA breaks induced by SN-38, a topoisomerase-1 inhibitor, in gastric cancer cell lines positive or negative for HER2 expression., Materials and Methods: NCI-N87 (HER2+) and MKN74 (HER2-) cells were exposed to SN-38 in the presence or absence of trastuzumab. Trastuzumab was added either prior to or after SN-38. Effects of trastuzumab on the induction of gamma-H2AX, a marker of DNA double-strand breaks, the cytotoxicity of SN-38 and cell cycle progression were determined., Results: When trastuzumab was administered following SN-38, it increased γH2AX levels and cytotoxicity of SN-38 in NCI-N87 cells, but not in MKN74 cells. In contrast, pretreatment with trastuzumab reduced SN-38-induced γH2AX expression and cytotoxicity of SN-38 in NCI-N87 cells, but not in MKN74 cells. Trastuzumab delayed cell cycle progression in NCI-N87 cells only., Conclusion: Trastuzumab has opposing effects on SN-38-induced double-strand breaks and cytotoxicity depending on the order of administration of the two agents.

Gastrointestinal involvement in cytomegalovirus (CMV) infection is well documented among immunocompromised patients and is also observed in immunocompetent individuals. The presentation of this infection can sometimes mimic those of other diseases, thus making accurate diagnosis difficult. We herein report a rare case of an immunocompetent elderly adult with gastrointestinal CMV infection that presented as a vanishing tumor at the cecum. A 76-year old man initially presented with lower abdominal pain. Colonoscopy revealed a tumorous lesion with irregular ulceration observed at the ileocecal valve. Histological findings of a biopsy specimen revealed intranuclear inclusions which were positive for CMV on immunohistochemical staining. However, this tumorous lesion disappeared within 7 wk from the initial hospital visit without any further treatment. Inflammatory pseudotumors associated with CMV infection should be considered as a differential diagnosis of tumorous lesions in the colon, even in immunocompetent adults.

Background: Guggulsterone, a plant polyphenol guggulipid, has several antitumour effects and acts as an antagonist for the farnesoid X receptor. Although bile acids induce caudal-related homeobox 2 (CdX2), a transcription factor essential for intestinal development and gut tumourigenesis, the effects of guggulsterone on regulation of CdX2 in the gut are unknown., Materials and Methods: Regulation of CdX2 expression by treatment with bile acids and/or guggulsterone was analysed by immunoblot analysis in human gut-derived adenocarcinoma, Bic-1 cells. Nuclear factor-kappaB (NF-kappaB) activity and the cell cycle distribution were also examined., Results: Chenodeoxycholic acid and deoxycholic acid increased CdX2 expression in Bic-1 cells. Guggulsterone reduced bile acid-induced and constitutive CdX2 expression at 5 microM. Guggulsterone (up to 5 microM) did not affect cell viability or the cell cycle and did not attenuate bile acid-induced or constitutive NF-kappaB activation., Conclusion: Guggulsterone may be used as a novel drug to target CdX2 expression in certain gut adenocarcinomas.

We report an elderly patient with esophageal adenocarcinoma in whom a complete response (CR) was obtained by chemoradiotherapy using daily low-dose nedaplatin (CDGP) and continuous infusion of 5-FU. A 86-year-old man who had non-tuberculous mycobacterial infection was admitted for dysphagia, and diagnosed with Stage II A (T2N0M0) esophageal adenocarcinoma of the lower esophagus according to the TNM classification (sixth edition) of the International Union against Cancer (UICC). Chemoradiotherapy using daily low-dose CDGP and continuous infusion of 5- FU was performed, and thereafter one cycle of chemotherapy using CDGP and 5-FU was added. As the side effects of treatment, grade 3 leucopenia was observed while he was receiving chemoradiotherapy. A year later, he presented with grade 2 pericardial and pleural effusion and recovered with conservative treatment. CR was obtained and has been continued for two years. Definitive chemoradiotherapy using daily low-dose CDGP and continuous infusion of 5-FU is an effective choice for elderly and high-risk patients with esophageal adenocarcinoma.