Adherent-invasive Escherichia coli LF82 disrupts the tight junctions of Caco-2 monolayers.

BACKGROUND AND STUDY AIMS: Adherent invasive Escherichia coli (AIEC) are enriched in IBD (inflammatory bowel disease) patients, but the role and mechanism of AIEC in the intestinal epithelial barrier is poorly defined. We evaluated the role of the AIEC strain E. coli LF82 in vitro and investigated the role of Th17 in this process. MATERIAL AND METHODS: After coincubation with AIEC, the epithelial barrier integrity was monitored by epithelial resistance measurements. The permeability of the barrier was evaluated by TEER (trans-epithelial electrical resistance) and mucosal-to-serosal flux rate. The presence of interepithelial tight junction proteins ZO-1 and Claudin-1 were determined by immunofluorescence and western blot analysis. Cytokines in the cell culture supernatant were assayed by enzyme-linked immunosorbent assay (ELISA). RESULTS: AIEC infection decreased TEER and increased the mucosal-to-serosal flux rate of Lucifer yellow in the intestinal barrier model in a time- and dose-dependent manner. AIEC infection decreased the expression and changed the distribution of ZO-1 and claudin-1. It also induced the secretion of cytokines such as TNF-α and IL-17. CONCLUSION: AIEC strain E. coli LF82 increased the permeability and disrupted the tight junctions of the intestinal epithelial barrier, revealing that AIEC plays an aggravative role in the inflammatory response.

Effectiveness of Water-Assisted Colonoscopy without Sedation in Patients with Ulcerative Colitis.

BACKGROUND: Studies have found that water-assisted colonoscopy (WAC) including water immersion colonoscopy (WIC) and water exchange colonoscopy (WEC) is superior to air insufflation colonoscopy (AIC) in terms of the cecal intubation rate. However, the application of WAC in ulcerative colitis (UC) has rarely been reported. This study aimed to explore the effectiveness of WAC without sedation in patients with UC. METHODS: One hundred and seventy-two UC patients were randomly divided into the AIC group (n = 56), WIC group (n = 58), and WEC group (n = 58). The cecal intubation rate, abdominal pain score, operator difficulty, bowel cleanliness, insertion, and total time were compared. RESULTS: The cecal intubation rate was higher in the WIC (91.4% vs. 75.0%; mean difference = 16.4%; 95% CI: 3.0-29.8%) and WEC (93.1% vs. 75.0%; mean difference = 18.1%; 95% CI: 5.0-31.2%) compared to the AIC group, while there was no difference between the WIC and WEC groups. The abdominal pain score and operator difficulty were lower in the WIC and WEC groups than in the AIC group, while there was no difference between the WIC and WEC groups. The bowel cleanliness during withdrawal was higher in the WIC and WEC groups than in the AIC group, while the WEC was superior to WIC. Compared with the AIC and WIC groups, the insertion time and total time were longer in the WEC group, and there was no difference in the AIC group and WIC group. CONCLUSION: In comparison with AIC, WAC can increase the cecal intubation rate, reduce abdominal pain scores and improve bowel cleanliness in patients with UC.

Adherent-invasive Escherichia coli LF82 aggravated intestinal inflammation in colitis mice by affecting the gut microbiota and Th17/Treg cell differentiation balance.

The imbalance of Th17 and Treg cell differentiation, intestinal flora imbalance, and intestinal mucosal barrier damage may be important links in the occurrence and development of inflammatory bowel disease (IBD) since Th17 and Treg differentiation are affected by the intestinal flora. This study aimed to explore the effect of Escherichia coli (E. coli) LF82 on the differentiation of Th17 and Treg cells and the role of the intestinal flora in mouse colitis. The effects of E. coli LF82 infection on intestinal inflammation were evaluated by analyzing the disease activity index, histology, myeloperoxidase activity, FITC-D fluorescence value, and claudin-1 and ZO-1 expression. The effects of E. coli LF82 on the Th17/Treg balance and intestinal flora were analyzed by flow cytometry and 16S rDNA sequencing. Inflammatory markers, changes in the intestinal flora, and Th17/Treg cells were then detected after transplanting fecal bacteria from normal mice into colitis mice infected by E. coli LF82. We found that E. coli LF82 infection can aggravate the intestinal inflammation of mice colitis, destroy their intestinal mucosal barrier, increase intestinal mucosal permeability, and aggravate the imbalance of Th17/Treg differentiation and the disorder of intestinal flora. After improving the intestinal flora imbalance by fecal bacteria transplantation, intestinal inflammation and intestinal mucosal barrier damage were reduced, and the differentiation balance of Th17 and Treg cells was restored. This study showed that E. coli LF82 infection aggravates intestinal inflammation and intestinal mucosal barrier damage in colitis by affecting the intestinal flora composition and indirectly regulating the Th17 and Treg cell differentiation balance.

Case Report: Unusual Cause of Fever in Ulcerative Colitis Treated with Infliximab.

Introduction: Patients with inflammatory bowel disease are at high risk for opportunistic infections, and fungal infections are relatively uncommon among various infections. Case: This case is the first reported ulcerative colitis accompanied with Cryptococcus neoformans infection after infliximab treatment. In the course of the disease, the patients had a variety of opportunistic infections, including viruses, fungi and bacteria. Conclusion: This case highlights the importance of paying continued attention to opportunistic infections for patients with inflammatory bowel disease.

The AC006262.5-miR-7855-5p-BPY2C axis facilitates hepatocellular carcinoma proliferation and migration.

Hepatocellular carcinoma (HCC) is typically fatal, and patients with hepatocellular carcinoma are usually diagnosed at the late stages. Although the treatments for HCC have been rapidly advancing, novel targets for HCC are still desperately needed, especially for targeted therapies. Here, we identified an enriched long non-coding RNA, AC006262.5, associated with HCC, that promoted the proliferation, migration, and invasiveness of HCC cells, both in vitro and in vivo. In addition, our results revealed that AC006262.5 bound to and regulated miR-7855-5p, a tumor-suppressive miRNA, in HCC. Moreover, our data show that AC006262.5 regulates the expression of BPY2C via miR-7855-5p. Finally, we found that AC006262.5 and miR-7855-5p formed a regulatory loop. Upregulation of AC006262.5 resulted in decreased expression of miR-7855-5p, and downregulation of miR-7855-5p further facilitated the expression of AC006262.5. Our work provides novel targets for HCC diagnosis and treatment, and sheds light on the lncRNA-miRNA regulatory nexus that controls the pathology of HCC.

RP11-81H3.2 promotes gastric cancer progression through miR-339-HNRNPA1 interaction network.

Recent studies have demonstrated that various long non-coding RNAs (lncRNAs) participate in the gastric cancer (GC) development and metastasis. Some lncRNAs exert their regulatory function by interacting with microRNAs. Here we identified a novel lncRNA RP11-81H3.2 that was highly expressed in the GC tissue and cell lines. RP11-81H3.2 knockdown significantly inhibited the proliferation, migration, and invasion of GC cells. Mechanistically, we demonstrated that RP11-81H3.2 directly interacted with miR-339 while miR-339 regulated the HNRNPA1 expression by targeting HRRNPA1 3'-UTR. RP11-81H3.2-miR-339-HNRNPA1 interaction network regulated the GC cell proliferation, migration, and invasion. Moreover, our results confirmed that RP11-81H3.2 knockdown suppressed the tumor growth of GC in a xenograft model in vivo. In summary, the results suggest that RP11-81H3.2 functions as an oncogene in GC and could be utilized as a promising diagnosis and therapeutic marker for GC treatment.

IL-17 is a protection effector against the adherent-invasive Escherichia coli in murine colitis.

Inflammatory bowel disease (IBD) is caused by aberrant immune responses to the gut microbiota. Among the gut microbiota, adherent-invasive Escherichia Coli (AIEC) is thought to be the pathogen through invading the intestinal epithelial cells and causing inflammation. IL-17 secretion increase, induced by enhanced bacterial adhesion to the intestine epithelium, could on one hand protect the mucosa, but on the other hand, over amount of IL-17 initializes inflammation reactions that in turn damages the mucosa. The relationship between IL-17 and AIEC is still unclear. In this study, we tried to elucidate the function of IL-17 in AIEC-mediated colitis. Wild type (WT) and IL-17 knockout (IL-17 KO) mice were inoculated with AIEC strain E. coli LF82 and treated with dextran sodium sulphate (DSS). Histological examination of the colon was performed. Mucosa damage was assessed and scored. IL-22 and IL-17 in colon tissues were detected by ELISA, qPCR and immunohistochemistry methods. Transient AIEC colonization in IL-17 KO mice resulted in increased intestinal epithelial damage, systemic bacterial burden and mortality compared with WT controls. Moreover, IL-17 is required for the induction of IL-22 in the experimental animal models during AIEC strain E. coli LF82 colonization. These results indicate IL-17 plays a protective role in AIEC strain E. coli LF82 induced colitis by promoting IL-22 secretion.

Prevalence of colorectal cancer in patients with ulcerative colitis: A retrospective, monocenter study in China.

BACKGROUND: Ulcerative colitis-associated colorectal cancer (UC-CRC) is a serious complication of UC. Data on the clinical characteristics of patients in China are scarce. AIMS: We aimed to study the incidence, characteristics, treatment, and prognosis of CRC patients with a history of UC. MATERIALS AND METHODS: We identified patients with UC and followed them until the first occurrence of cancer, death, or emigration in a single study center in China. RESULTS: A total of 4 UC-associated CRC patients were identified among the 642 cases recorded from January 2000 to December 2012. The overall risk of cancer was 0.64%. The overall median duration of UC was 15.5 years (range 6-21 years) in patients with UC-associated CRC. Of these patients, 75% (3/4) were at an advanced stage when they were diagnosed. Longer disease duration and extensive colitis were identified as risk factors for developing CRC, and 5-aminosalicylic acid and steroid therapies were not identified as protective factors against UC-associated CRC. CONCLUSIONS: Patients with UC are at an increased risk for CRC. However, the prevalence of CRC in China remains lower than that in the West.

Interleukin-1ß induces autophagy by affecting calcium homeostasis and trypsinogen activation in pancreatic acinar cells.

The strong up-regulation of inflammatory mediators has been reported to play a key role in acute pancreatitis (AP). Elevated serum levels of interleukin-1ß (IL-1ß) are associated with the development of AP. However, the precise effect and mechanism of IL-1ß in AP remains obscure. In this study, we investigated the potential role and mechanism of IL-1ß in AP. We measured autophagy activation in response to IL-1ß in AR42J cells. The disrupting effects of IL-1ß on cellular Ca(2+) were observed. To determine whether the disruption of Ca(2+) signaling has protective effects in vivo during AP, male C57BL/6 mice were treated with cerulein to induce AP. We found that the treatment of AR42J cells with IL-1ß triggered autophagy and that the autophagic flux was impaired. In addition, IL-1ß induced Ca(2+) release from the ER. Furthermore, the expression of the ER stress markers GRP78 and IRE1 also increased. 2APB, an antagonist of the InsP3 receptor, inhibited increased expression of autophagy markers. Subsequent biochemical assays revealed that co-culture with IL-1ß could induce the activation of trypsinogen to trypsin and reduce the viability of acinar cells. Pathological changes of the pancreas were also observed in vivo. We found that the pathological injuries of the pancreas were significantly alleviated in mice co-treated with 2APB. Taken together, our results indicate that IL-1ß can induce trypsin activation and decrease cellular viability in pancreatic acinar cells. These effects depend on impaired autophagy via intracellular calcium changes. Ca(2+) signaling may become a promising therapeutic target in the treatment of pancreatitis.

Preventive effects of Escherichia coli strain Nissle 1917 with different courses and different doses on intestinal inflammation in murine model of colitis.

OBJECTIVE: To analyze the in vivo effect of Escherichia coli Nissle 1917 (EcN) with different courses and different doses to Sprague-Dawley rats with trinitrobenzene sulfonic acid (TNBS)-induced colitis. METHODS: The probiotic was orally administered with different courses of treatment (with or without pre-administration) and different doses (10(7)-10(9) CFU/day) to Sprague-Dawley rats with TNBS-induced colitis. Therapeutic effects, levels of cytokine in serum, mRNA and protein expression were analyzed. RESULTS: Oral EcN administration after TNBS-induced improved colitis dose dependently. In parallel, a reduction of disease activity index and colonic MPO activity together with a decreased level of TNF-α and a trend of increased IL-10 expression was detected. Pre-administration of 10(7)CFU/day EcN to TNBS-treated rats resulted in a significant protection against inflammatory response and colons isolated from these rats exhibited a more pronounced expression of ZO-1 than the other groups. In the group of pre-administration of 10(9)CFU/day, the condition was not improved but deteriorated. CONCLUSIONS: This study convincingly demonstrates that pre-administration of probiotic EcN with low dose is able to protect colitis of rats and mediate up-regulation of ZO-1 expression, but long-term of high-dose EcN may do harm to colitis.

DBC1 is over-expressed and associated with poor prognosis in colorectal cancer.

BACKGROUND: Deleted in breast cancer 1 (DBC1) was initially cloned from a region homozygously deleted in breast cancers, but its role in colorectal cancer remains unknown. The present study aims to examine the expression level of DBC1 and assess its prognostic value in human colorectal cancer. METHODS: Immunohistochemical staining was performed to detect the expression level of DBC1 in a series of 186 colorectal cancer patients. Immunohistochemical staining results were analyzed and compared statistically with various clinicopathological characters and overall survival. RESULTS: Compared with the corresponding non-tumor tissues, a higher expression level of DBC1 was detected in colorectal cancer (P < 0.01). Tissue microarray analysis revealed that DBC1 expression is significantly associated with tumor histological grade, TNM stage and metastatic status (P < 0.01). Importantly, Kaplan-Meier analysis showed that DBC1 expression is associated with shorter overall survival (P < 0.01). Univariate Cox regression suggested that DBC1 expression, poorly differentiation status and the presence of lymph node metastasis predict shorter overall survival in colorectal cancer (P < 0.05). Multivariate Cox regression analysis indicated that DBC1 acts as an independent prognostic factor in colorectal cancer (P < 0.01). CONCLUSIONS: These results suggest that DBC1 is over-expressed in colorectal cancer and that it might serve as a predictor for selecting patients at high risk of poor prognosis.

Decreased expression of HOXB9 is related to poor overall survival in patients with gastric carcinoma.

BACKGROUND: Studies have demonstrated the implication of HOXB9 in tumorigenesis, but its role in gastric carcinoma remains unknown. AIMS: To investigate the expression and prognostic value of HOXB9 in patients with gastric carcinoma. METHODS: The localization and expression of HOXB9 in gastric cancer cells lines were detected by immunofluorescence and western blot. The mRNA and protein expression level of HOXB9 was detected in subjects with gastric carcinoma and paired non-cancerous tissues. Correlation between HOXB9 expression and clinicopathological parameters, the association of HOXB9 expression with the patients' survival rate was also assessed. RESULTS: HOXB9 was predominantly localized in the cell nucleus. A significant decrease in HOXB9 intensity in poorly differentiated gastric cancer cells is evident (P<0.01). A lower mRNA and protein expression level of HOXB9 was detected in gastric carcinoma (P<0.01). Decreased expression of HOXB9, poorly differentiation status and the presence of lymph node metastasis predict shorter overall survival (P<0.05). Patients without HOXB9 expression had a lower overall survival rate (P<0.01). Multivariate Cox regression analysis showed HOXB9 was an independent prognostic factor in gastric carcinoma (P<0.01). CONCLUSIONS: HOXB9 is down-regulation in gastric carcinoma and may be a novel prognostic marker for poorer clinical outcome for patients with gastric carcinoma.

The biodiversity and composition of the dominant fecal microbiota in patients with inflammatory bowel disease.

Clinical and experimental observations in animal models indicate that intestinal commensal bacteria are involved in the initiation and amplification of inflammatory bowel disease (IBD). As the majority of colonic bacteria cannot be identified by culture techniques, the aim of this study was to use sequence-based methods to investigate and characterize the composition of the dominant fecal microbiota in both patients with inflammatory bowel disease and healthy subjects. Fecal microbiota was isolated and quantified using real-time quantitative polymerase chain reaction. Denaturing gradient gel electrophoresis (DGGE) of 16S rDNA was used to evaluate the diversity of the dominant species. Analysis of individual bacterial groups showed a greater change in the fecal microbiota of patients with IBD, especially in those with active ulcerative colitis and active Crohn's disease. DGGE demonstrated the diversity of microbial flora in ulcerative colitis and Crohn's disease was less than in healthy subjects. Our results provide a better understanding of changes in fecal microbiota among patients with inflammatory bowel disease.

Berberine increases the expression of NHE3 and AQP4 in sennosideA-induced diarrhoea model.

Berberine, a compound isolated from Chinese Goldthread Rhizome, has been widely used as a non-prescription drug to treat diarrhoea in China. Previous studies have demonstrated multiple pharmacological activities for berberine, including its significant role in antimicrobial activity. However, its effect on ion exchange and water transfer remains unclear. The present study aims to explore the effect of berberine on the expression of Na(+)/H(+) exchanger3 (NHE3) and aquaporin4 (AQP4) in both diarrhoea mouse model induced by sennosideA and human intestinal epithelium cell line (HIEC). Semi-quantitative RT-PCR, immunohistochemistry and western blotting were adopted to detect the mRNA and protein expression levels of NHE3 and AQP4. Furthermore, the absorption of berberine and the PKC activity were detected by HPLC and PepTag® Assay to elucidate the underlying mechanisms. It was shown that the expression levels of NHE3 and AQP4 were significantly increased in the diarrhoea mice treated with berberine compared with the untreated diarrhoea mice. Similarly, the expression levels of NHE3 and AQP4 were strikingly enhanced in HIEC co-treated with sennosideA and berberine compared with samples treated with sennosideA only. We also found the maximal absorption of berberine to be approximately 0.01%. In addition, no significant change of PKC activity was observed in the different HIEC treated groups. These results showed that berberine was able to increase the expression of NHE3 and AQP4, suggesting that berberine might exhibit its anti-diarrhoeal effect partially by enhancing the absorption of Na(+) and water.

Activating transcription factor 4 confers a multidrug resistance phenotype to gastric cancer cells through transactivation of SIRT1 expression.

BACKGROUND: Multidrug resistance (MDR) in gastric cancer remains a major challenge to clinical treatment. Activating transcription factor 4 (ATF4) is a stress response gene involved in homeostasis and cellular protection. However, the expression and function of ATF4 in gastric cancer MDR remains unknown. In this study, we investigate whether ATF4 play a role in gastric cancer MDR and its potential mechanisms. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrated that ATF4 overexpression confered the MDR phenotype to gastric cancer cells, while knockdown of ATF4 in the MDR variants induced re-sensitization. In this study we also showed that the NAD(+)-dependent histone deacetylase SIRT1 was required for ATF4-induced MDR effect in gastric cancer cells. We demonstrated that ATF4 facilitated MDR in gastric cancer cells through direct binding to the SIRT1 promoter, resulting in SIRT1 up-regulation. Significantly, inhibition of SIRT1 by small interfering RNA (siRNA) or a specific inhibitor (EX-527) reintroduced therapeutic sensitivity. Also, an increased Bcl-2/Bax ratio and MDR1 expression level were found in ATF4-overexpressing cells. CONCLUSIONS/SIGNIFICANCE: We showed that ATF4 had a key role in the regulation of MDR in gastric cancer cells in response to chemotherapy and these findings suggest that targeting ATF4 could relieve therapeutic resistance in gastric cancer.