Abstract. The gastric pathogen, helicobacter pylori (H. pylori), has been associated with the progression of gastric cancer. It was previously reported that H. pylori induced urokinase plasminogen activator receptor (uPAR) expression and stimulated cell invasiveness in human gastric cancer AGS cells. However, the precise mechanisms for how H. pylori upregulates uPAR are unclear. This study investigated the underlying signal pathways in H. pylori-induced uPAR in human gastric cancer AGS cells. The intracellular H 2 O 2 content, as determined using H 2 O 2 -sensitive probe 2',7'-dichlorodihydrofluorescein, increased after the H. pylori treatment. N-acetyl cysteine (NAC), an antioxidant, prevented the H. pylori-induced production of H 2 O 2 and uPAR expression. In addition, exogenous H 2 O 2 was found to increase uPAR mRNA expression and its promoter activity. Sitedirected mutagenesis of the potential NF-κB element in the uPAR promoter showed that the redox-sensitive transcription factor NF-κB was essential for H. pylori-induced uPAR expression. The expression of vectors encoding a mutatedtype NF-κB-inducing kinase and I-κB, and a specific inhibitor of NF-κB (BAY11-7082) decreased the H. pyloriinduced uPAR promoter activity. Chromatin immunoprecipitation and the electrophoretic mobility shift assay confirmed that H. pylori increased the DNA binding activity of NF-κB. With the aid of NAC and H 2 O 2 , it was determined that reactive oxygen species (ROS) is an upstream signaling molecule for activating the NF-κB induced by H. pylori. The enhanced AGS cell invasiveness by H. pylori was partially abrogated by an NAC and BAY11-7082 treatment. These results suggest that the ROS and NF-κB signaling pathway is important in H. pylori-induced uPAR expression and the increased cell invasiveness of human gastric cancer AGS cells.

More efficient isolation and identification of cancer stem cells (CSCs) would help in determining their fundamental roles in tumor biology. The classical tool for this purpose is anchorage-independent tumorsphere culture. We compared the effects of differently textured culture plates and serum deprivation on the acquisition of CSC properties of A172 glioblastoma cells. Cells were cultured on standard polystyrene-treated plates, ultra-low attachment, poly (2-hydroxyethyl methacrylate)-coated plates, and 1% agar-coated plates with 10% serum or in serum-free glioblastoma sphere medium (GBM). Based on mitochondrial reductase activity and subG1 proportions, non-adherent conditions had a greater impact on A172 cell viability than serum deprivation. Among the stemness-related genes, SOX-2 expression was significantly upregulated by serum deprivation under non-adherent conditions, while several epithelial-to-mesenchymal transition (EMT)-related genes were less dependent on serum. In addition, reactive oxygen species (ROS) accumulation in A172 cells was significantly increased in GBM under non-adherent conditions. Despite the correlation between SOX-2 induction and ROS accumulation, treatment with the ROS scavenger N-acetyl-l-cysteine did not prevent SOX-2 expression, suggesting that ROS accumulation is not an essential requirement for induction of SOX-2. Our results suggested that cultivation of cancer cells under conditions of serum deprivation in an anchorage-independent manner may enrich SOX-2-expressing CSC-like cells in vitro.

The Bis protein is known to be involved in a variety of cellular processes including apoptosis, migration, autophagy as well as protein quality control. Bis expression is induced in response to a number of types of stress, such as heat shock or a proteasome inhibitor via the activation of heat shock factor (HSF)1. We report herein that Bis expression is increased at the transcriptional level in HK-2 kidney tubular cells and A172 glioma cells by exposure to oxidative stress such as H2O2 treatment and oxygen-glucose deprivation, respectively. The pretreatment of HK-2 cells with N-acetyl cysteine, suppressed Bis induction. Furthermore, HSF1 silencing attenuated Bis expression that was induced by H2O2, accompaniedby increase in reactive oxygen species (ROS) accumulation. Using a series of deletion constructs of the bis gene promoter, two putative heat shock elements located in the proximal region of the bis gene promoter were found to be essential for the constitutive expression is as well as the inducible expression of Bis. Taken together, our results indicate that oxidative stress induces Bis expression at the transcriptional levels via activation of HSF1, which might confer an expansion of antioxidant capacity against pro-oxidant milieu. However, the possible role of the other cis-element in the induction of Bis remains to be determined.

Chungkookjang is a Korean fermented soybean containing microorganisms, proteinase, and diverse bioactive compounds, including a high concentration of isoflavones and peptides. Growth of breast cancer MCF7 cells decreased dependent on the concentration of fermented soybean extracts. The effect of fermented soybean on cellular gene expression was determined in a systematic manner comprehensively. DNA microarray analysis was performed using 25,804 probes. Ninety one genes whose expression levels were significantly changed were selected. TGFβI and Smad3 were upregulated. Downregulation of inflammation-related CSF2, CSF2RA, and CSF3 was found. Differential expression of chemokines CCL2, CCL3, CCL3L3, CXCL1, and CXCL2 were observed. Network analysis identified ERβ in the network. Based on the experimental results, taking fermented soybean might be helpful for preventing breast cancer by a mechanism activating TGFβ pathway and depressing inflammation.

Aims/hypothesis B cell CLL/lymphoma 2 (BCL-2)-interacting cell death suppressor (BIS), known as an anti-stress and antiapoptotic protein, has been reported to modulate susceptibility to oxidative stress. This study investigated the potential role of BIS as an antioxidant protein in diabetic nephropathy. Methods Diabetes was induced in BIS-heterozygote (BIS-HT) mice via streptozotocin injections and the resulting phenotypes were compared with those of BIS-wild-type (BIS-WT) mice over the 20 weeks following diabetes induction.Results Renal injuries, represented by increased plasma creatinine levels and increased albuminuria, were greater in diabetic BIS-HT mice than in diabetic BIS-WT mice, and were accompanied by a significant increase in reactive oxygen species (ROS) and oxidative stress markers. Moreover, renal pathological changes and the apoptotic process were accelerated in diabetic BIS-HT mice compared with diabetic BIS-WT mice with the same degree of hyperglycaemia; all were restored by 4-hydroxy-2,2,6,6-tetramethylpiperidine-Noxyl (tempol) treatment. The levels of NADPH oxidase and related proteins were not significantly higher in diabetic BIS-HT mice compared with diabetic BIS-WT mice. However, levels of superoxide dismutase (SOD)1 and SOD2 increased on the induction of diabetes in BIS-WT mice but not in BIS-HT mice, correlating with the total SOD activity. An in vitro study showed that knockdown of BIS production also resulted in impaired induction of SOD activity as well as SOD levels in HK-2 and NMS cells, concomitant with significant ROS accumulation. Conclusion/interpretation Our results suggest that the decreased antioxidant capacity of BIS aggravates diabetic nephropathy in diabetic BIS-HT mice, possibly as a result of the disruption in the regulation of SOD protein quality under oxidative stress. Electronic supplementary material The online version of this article (doi:10.1007/s00125-013-3064-0) contains peer-reviewed but unedited supplementary material, which is available to authorised users.

Aims: GS28 (Golgi SNARE protein, 28 kDa), a member of the soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNARE) protein family, plays a critical role in mammalian endoplasmic reticulum (ER)-Golgi or intra-Golgi vesicle transport. To date, few researches on the GS28 protein in human cancer tissues have been reported. In this study, we assessed the prognostic value of GS28 in patients with colorectal cancer (CRC).Methods and results: We screened for GS28 expression using immunohistochemistry in 230 surgical CRC specimens. The CRCs were right-sided and left-sided in 28.3% (65/230) and 71.3% (164/230) of patients, respectively. GS28 staining results were available in 214 cases. Among these, there were 26 nuclear predominant cases and 188 non-nuclear predominant cases. Stromal GS28 expression was noted in 152 cases of CRC. GS28 nuclear predominant immunoreactivity was significantly associated with advanced tumour stage (p = 0.045) and marginally associated with perineural invasion (p = 0.064). Decreased GS28 expression in the stromal cells was significantly associated with lymph node metastasis (N stage; p = 0.036). GS28 expression was not associated with epidermal growth factor receptor (EGFR) immunohistochemical positivity or KRAS mutation status. Investigation of the prognostic value of GS28 with Kaplan-Meier analysis revealed a correlation with overall survival (p = 0.004). Cases with GS28 nuclear predominant expression had significantly poorer overall survival than those with a non-nuclear predominant pattern.Conclusions: Taken together, these results indicate that GS28 nuclear predominant expression could serve as a prognostic marker for CRC and may help in identifying aggressive forms of CRC.

Golgi S‐nitro‐N‐acetylpenicillamine receptor complex 1 (GS28) has been implicated in Golgi vesicle transport. We examined the role of GS28 and its molecular mechanisms in sodium nitroprusside (SNP)‐induced cell death using GS28 siRNA (siGS28)‐transfected HeLa cells. Significant inhibition of cytotoxicity was observed in the cells treated with SNP, and photodegraded SNP showed equal cytotoxicity to SNP. Pretreatment with an ERK inhibitor or siErk1 cotransfection blocked the inhibition in cytotoxicity. Additionally, increased phosphorylation of ERK was maintained in the cells treated with SNP, and Nrf2 level was dependent on ERK phosphorylation. However, pretreatment with a pan‐caspase inhibitor had no effect on cytotoxicity or procaspase‐3 level. Pretreatment with an autophagy inhibitor or siATG5 cotransfection blocked the inhibition of cytotoxicity. The changes of LC3 corresponded to that in siErk1‐cotransfected cells. These data suggest that GS28 has an inductive role in SNP‐induced cell death via inhibition of ERK, leading to inhibition of autophagic processes in HeLa cells.

Purpose: We performed this study retrospectively to review the diagnostic yield of colonoscopies in children and adolescents with various gastrointestinal symptoms and to investigate the relationship between presenting symptoms and the colonoscopic findings in a secondary hospital. Methods: We reviewed the medical records of patients under the age of 19-years who underwent ileocolonoscopy between January 2001 and December 2010. The total number of patients (n=238) were divided into three age groups and six symptom groups. We analyzed clinical characteristics and the colonoscopic findings, and compared the colonoscopic yield between each groups. Results: The median age of the patients was 16.1 (3.1∼18.9) years. The most common presenting symptoms were lower gastrointestinal (GI) bleeding (48.1%) in the ≤12 years group (n=27), chronic abdominal pain (31.8%) in the 13∼15 years group (n=85), and chronic diarrhea (34.9%) in the ≥16 years group (n=126). Positive colonoscopic findings were found in 21.4% of the bowel habit change group (n=28), 51.9% of the low GI bleeding group (n=54), 37.7% of the chronic diarrhea group (n=69), and 94.4% of the group with suspected inflammatory bowel disease (IBD) (n=18), 38.9% of the chronic abdominal pain group (n=54) and 13.3% of the anemia group (n=15). The diagnostic yield of the total examination was 42.0%. The suspected IBD group had a higher yield than the presenting symptom groups (p＜0.001). Conclusion: Colonoscopy is a safe and useful investigation in children and adolescents with suspected colonic disease. The diagnostic yield of colonoscopy is higher in patients presenting with suspected IBD. Pediatricians practicing in primary or secondary care settings should recommend colonoscopy for patients with suspected IBD. (Korean J Pediatr Gastroenterol Nutr 2011; 14: 368∼375)