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Background Inflammatory bowel disease (IBD) is a complex chronic disorder characterized by systemic inflammation, which may cause abnormal state of coagulation, resulting in cardiac events. This study aimed to investigate the incidences and risks of cardiac events in patients with IBD in China. Methods A retrospective cohort study was performed comprising 1435 patients with IBD from 12 IBD centers in China. Cases were matched with 1588 eligible participants without IBD from 12 medical centers according to age, sex, and laboratory parameters. Results Patients with IBD in China exhibited significantly higher incidences of ischemic heart disease (IHD; coronary heart disease included) but lower frequencies of right bundle branch block and premature contraction than those of matched controls. The risk of IHD increased in patients with IBD, peaking at the age of 18-35 years. Female patients with IBD were more likely to experience IHD than male patients. The C-reactive protein (CRP) levels and neutrophil count in the peripheral blood were positively related with the risk of IHD among patients with Crohn’s disease, whereas plasma fibrinogen levels were negatively related with the risk of IHD both in patients with Crohn’s disease and ulcerative colitis. Conclusions The risk of IHD is increased in patients with IBD, especially in young female patients with IBD when compared with matched non-IBD subjects. The CRP and plasma fibrinogen levels and neutrophil count in the peripheral blood may be potential predictors associated with the occurrence of IHD in patients with IBD. The study’s findings have significant implications for the management and prevention of cardiac events in patients with IBD.

Insulin, as a growth factor, can increase the risk of certain types of cancer. The present study showed that insulin promoted the proliferation of hepatocellular carcinoma cells in vitro and in vivo through pyruvate kinase M2 (PKM2), which is a rate-limiting enzyme in the process of glycolysis. Moreover, the expression of PKM2 was up-regulated by insulin at the posttranslational level in a nuclear orphan receptor TR3-dependent manner. In addition, insulin could enhance the interaction between PKM2 and TR3 and protect PKM2 from degradation. Our results identified a specific mechanism of insulin affecting cancer metabolism and thus promoting cancer progression, and they contribute to a better understanding of the observation that insulin is linked to an increased cancer risk under hyperinsulinemic conditions.

Background Apolipoprotein H (APOH), also known as beta2-glycoprotein I (beta2-GPI), is an acute phase protein in hepatitis B virus (HBV) infection and binds to hepatitis B surface antigen (HBsAg) with high-affinity. APOH expression is upregulated by HBV and the large surface protein (LHBs), but also elevated in HBV-related hepatoma cells. Previous studies show that intracellular retention of HBsAg induces endoplasmic reticulum (ER) stress, a key driver of hepatocyte damage during chronic liver injury, but the mechanisms are unclear. We hypothesize that APOH mediates HBV-induced ER stress through increased retention of HBsAg. Methods VR-APOH-myc and VR-LHBs-flag plasmids were constructed by PCR using pcDNA3.1(-)-APOH or an HBV expression vector, respectively. APOH and ER stress markers were examined at protein and mRNA levels by Western Blot or RT-qPCR. HBsAg titer was assayed by ELISA. RNA-seq was performed to elucidate the transcriptional impact of APOH manipulation in HBV-producing cells (HepG2.2.15 cells). Results We found that HBV upregulates APOH expression in 293 T cells, and APOH overexpression subsequently inhibits secretion of HBsAg. Next, we show that LHBs overexpression in conjunction with APOH leads to ER stress in 293 T cells, as evidenced by production of the binding immunoglobulin protein (BiP) and C/EBP homologous protein (CHOP), as well as increased splicing of X-box binding protein 1 (XBP1). We further observed that loss of beta2-GPI reduced CHOP expression in HepG2.2.15 cells, while beta2-GPI overexpression enhanced CHOP production. Conclusion The interaction of beta2-GPI and HBV initiates ER stress through driving intracellular retention of HBsAg and activates the UPR.

Mindin is important in broad spectrum of immune responses. On the other hand, we previously reported that mindin attenuated human colon cancer development by blocking angiogenesis through Egr‐1–mediated regulation. However, the mice original mindin directly suppressed the syngenic colorectal cancer (CRC) growth in our recent study and we aimed to further define the role of mindin during CRC development in mice. We established the mouse syngeneic CRC CMT93 and CT26 WT cell lines with stable mindin knock‐down or overexpression. These cells were also subcutaneously injected into C57BL/6 and BALB/c mice as well as established a colitis‐associated colorectal cancer (CAC) mouse model treated with lentiviral‐based overexpression and knocked‐down of mindin. Furthermore, we generated mindin knockout mice using a CRISPR‐Cas9 system with CAC model. Our data showed that overexpression of mindin suppressed cell proliferation in both of CMT93 and CT26 WT colon cancer cell lines, while the silencing of mindin promoted in vitro cell proliferation via the ERK and c‐Fos pathways and cell cycle control. Moreover, the overexpression of mindin significantly suppressed in vivo tumour growth in both the subcutaneous transplantation and the AOM/DSS‐induced CAC models. Consistently, the silencing of mindin reversed these in vivo observations. Expectedly, the tumour growth was promoted in the CAC model on mindin‐deficient mice. Thus, mindin plays a direct tumour suppressive function during colon cancer progression and suggesting that mindin might be exploited as a therapeutic target for CRC.

Figure S1. Human GC cells were transfected with miR-632-mimic or inhibitor. (A) miRNA mimic upregulated miR-632 expression compared with the negative control in AGS and BGC823 cells. (B) miRNA inhibitor downregulated miR-632 expression compared with the negative control in MKN45 and MGC803 cells. The experiments were performed at least three times independently. **Pâ

Background Gastric cancer (GC) is a common malignant disease worldwide. Aberrant miRNAs expression contributes to malignant cells behaviour, and in preclinical research, miRNA targeting has shown potential for improving GC therapy. Our present study demonstrated that miR-632 promotes GC progression in a trefoil factor 1 (TFF1)-dependent manner. Methods We collected GC tissues and serum samples to detect miR-632 expression using real-time PCR. A dual-luciferase reporter assay was used to identify whether miR-632 directly regulates TFF1 expression. Tube formation and endothelial cell recruitment assays were performed with or without miR-632 treatment. Western blot and in situ hybridization assays were performed to detect angiogenesis and endothelial recruitment markers that are affected by miR-632. Results Our results showed that miR-632 is highly expressed in GC tissue and serum and negatively associated with TFF1 in GC. miR-632 improves tube formation and endothelial cell recruitment by negatively regulating TFF1 in GC cells. Recombinant TFF1 reversed miR-632-mediated angiogenesis. TFF1 is a target gene of miR-632. Conclusions Our study demonstrated that miR-632 promotes GC progression by accelerating angiogenesis in a TFF1-dependent manner. Targeting of miR-632 may be a potential therapeutic approach for GC patients. Electronic supplementary material The online version of this article (10.1186/s12885-018-5247-z) contains supplementary material, which is available to authorized users.

The trefoil factor family (TFF) is a group of short secretory peptides of gastric mucous neck cells. The loss of TFF2 protein expression enhances gastric inflammation and occurs in gastric cancer. In this study, we examined the effect of TFF2 on gastric cancer cell lines in vitro and characterized the interaction between TFF2 and Sp3, including the mechanisms that mediate this interaction, using genomics and proteomics approaches, as well as genetics techniques, such as RNA interference and gene knockdown. Assays were performed to examine the role of TFF2 and Sp3 in cancer cell proliferation, invasion and migration. We found that TFF2 expression inhibited the proliferation and invasion capacity of gastric cancer cells, and induced apoptosis. TFF2 interacted with the Sp3 protein, as shown by immunofluorescence staining and immunoprecipitation with western blot analysis. Sp3 knockdown in gastric cancer cells antagonized TFF2 anti-tumor activity. Additionally, TFF2 upregulated the expression of pro-apoptotic proteins, such as Bid, but downregulated the expression of NF-κB and the anti-apoptotic proteins, Bcl-xL and Mcl-1. By contrast, Sp3 knockdown significantly blocked TFF2 activity, affecting the expression of these proteins. The data from our study demonstrate that the antitumor activity of TFF2 is mediated by an interaction with the Sp3 protein in gastric cancer cells. Additional in vivo and ex vivo warrned in order to fully characterize this interaction.

// Ying Shi 1, * , Xiao-Xiao Huang 1, * , Guo-Bin Chen 1, 6, * , Ying Wang 1 , Qiang Zhi 1 , Yuan-Sheng Liu 1 , Xiao-Ling Wu 1 , Li-Fen Wang 1 , Bing Yang 1 , Chuan-Xing Xiao 1 , Hui-Qin Xing 5 , Jian-Lin Ren 1 , Yin Xia 3, 4 , Bayasi Guleng 1, 2 1 Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, China 2 State Key Laboratory of Cellular Stress Biology, Xiamen University, Xiamen, China 3 School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China 4 School of Biomedical Sciences Core Laboratory, The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China 5 Department of Basic Medical Sciences, Institute of Neuroscience, Medical College of Xiamen University, Xiamen, China 6 Xiamen Branch, Zhongshan Hospital, Fudan University, Xiamen, China * These authors contributed equally to this work Correspondence to: Bayasi Guleng, email: bayasi@xmu.edu.cn Yin Xia, email: Xia.Yin@cuhk.edu.hk Ying Shi, email: shiying@stu.xmu.edu.cn Keywords: Dragon, oxaliplatin resistance, colon cancer, JNK, p38 MAPK Received: December 21, 2015 Accepted: June 12, 2016 Published: June 30, 2016 ABSTRACT Colorectal cancer (CRC) is one of the most commonly diagnosed cancers and a major cause of cancer mortality. Chemotherapy resistance remains a major challenge for treating advanced CRC. Therefore, the identification of targets that induce drug resistance is a priority for the development of novel agents to overcome resistance. Dragon (also known as RGMb) is a member of the repulsive guidance molecule (RGM) family. We previously showed that Dragon expression increases with CRC progression in human patients. In the present study, we found that Dragon inhibited apoptosis and increased viability of CMT93 and HCT116 cells in the presence of oxaliplatin. Dragon induced resistance of xenograft tumor to oxaliplatinin treatment in mice. Mechanistically, Dragon inhibited oxaliplatin-induced JNK and p38 MAPK activation, and caspase-3 and PARP cleavages. Our results indicate that Dragon may be a novel target that induces drug resistance in CRC.

Aim Genetic analysis has revealed a subset of recurrently mutated genes and aberrant cellular signaling pathways in hepatocellular carcinoma. To investigate genetic alterations and dysregulated pathways in hepatocellular carcinoma, we performed targeted sequencing and exome analysis using next-generation sequencer. Methods We analyzed the somatic mutational profiles of 16 genes in primary hepatocellular carcinoma by targeted ultra-deep sequencing using nine pairs of specimens (tumor and peripheral blood) and whole-exome sequencing using one pair of samples. Results Overall, somatic mutations with high allele fraction were identified in tumor tissues by targeted deep sequencing. Somatic mutations with high allele fraction were observed in TP53 (3/9; 33%) and CTNNB1 (2/9; 22%) genes in five out of nine (55%) specimens. In vitro analysis showed that CTNNB1 H36P mutant protein identified in tumor samples was resistant to protein degradation and promoted cell proliferation. Exome sequencing identified SLIT3 mutation, implying that dysregulation of axon guidance genes is involved in the development of hepatocellular carcinoma. These results showed that TP53 and WNT/β-catenin signaling pathways were commonly mutated in hepatocellular carcinoma. Conclusion These results suggest that targeted sequencing and exome sequencing enable the identification of putative oncogenic driver mutations during the development of hepatocarcinoma.

Background Esophageal squamous cell carcinomas (ESCC) is the fourth most lethal cancer in China. Previous studies reveal several highly conserved mutational processes in ESCC. However, it remains unclear what are the true regulators of the mutational processes. Results We analyzed the somatic mutational signatures in 302 paired whole-exome sequencing data of ESCC in a Chinese population for potential regulators of the mutational processes. We identified three conserved subtypes based on the mutational signatures with significantly different clinical outcomes. Our results show that patients of different subpopulations of Chinese differ significantly in the activity of the “NpCpG” signature (FDR = 0.00188). In addition, we report ZNF750 and CDC27, of which the somatic statuses and the genetic burdens consistently influence the activities of specific mutational signatures in ESCC: the somatic ZNF750 status is associated with the AID/APOBEC-related mutational process (FDR = 0.0637); the somatic CDC27 copy-number is associated with the “NpCpG” (FDR = 0.00615) and the AID/APOBEC-related mutational processes (FDR = 8.69 × 10− 4). The burdens of germline variants in the two genes also significantly influence the activities of the same somatic mutational signatures (FDR

Background Gastric cancer (GC) is a common malignant disease worldwide. Aberrant miRNAs contribute to cells malignant behaviour, and targeted miRNAs have the potential ability in preclinical development to improve GC therapy. Our present studies demonstrated that miR-632-inhibitor attenuates GC progression in a trefoil factor 1 (TFF1)-dependent manner. Methods We collected GC tissues and plasma samples to detect the expression of miR-632 by using real-time PCR. Dual luciferase reporter assay was used to identify that miR-632 regulate TFF1 expression directly. Gene array, western blot and in situ hybridization assays were performed to detect the angiogenesis and endothelial recruitment markers which were affected by miR-632. In addition, candidates of histones regulating miR-632 were detected in GC cells. Results We found that miR-632 highly expressed in GC tissues and plasma (Fig.A) and identified that miR-632-inhibitor worked against tumour angiogenesis and endothelial recruitment by negatively regulated TFF1 expression (Fig.B-E). Recombinant protein of TFF1 reversed the angiogenesis increased by miR-632. We also found that miR-632 affected angiogenesis marker CD34 and MMP9 (Fig.F) and was degraded by histones H3K4 me3 and H3K27ac. Conclusions Thus, our study demonstrated that miR-632-inhibitor attenuates gastric cancer progression by suppressing angiogenesis in a TFF1-dependent manner. miR-632-inhibitor may be as a novel therapeutic approach for GC patients.

Figure S5. Correlation of the somatic events with the genetic burdens of the SMGs in ESCC. (a) The genetic burdens of PTCH1 are associated with the activity of the “AID/APOBEC-2” signature. (b) The genetic burdens of NOTCH1 are associated with the frequencies of C > G. (c) The genetic burdens of TP53 and PTCH1 are associated with the frequencies of T > C. FDR is based on the adjusted SKAT P values, in which the age, the clinical stage and ancestry are considered as covariates. (PDF 278 kb)

Figure S1. Significantly mutated genes in 302 ESCC. The samples are sorted by the counts of somatic mutations per megabase, with the synonymous and non-synonymous mutations shown in different colors. (top); the Significantly mutated genes (FDRâ

Figure S2. Significantly modified subnetworks in ESCC. The subnetworks are identified by HotNet2 from public protein-protein interactions databases of HINT+HI2012 (a), HPRD (b), iRefIndex (c) and MultiNet (d). The colored nodes represent the genes with different types of somatic alterations in ESCC, the sizes of the nodes correspond to the frequency of alteration in the population. All the subnetworks are identified with the minimum edge weight (δ), the minimum size of subnetwork (k) and the P less than 0.05. (PDF 158 kb)

Figure S3. Population stratification of 302 ESCC patients. Two hundred eight genotyped reference individuals are obtained from TGP including 103 CHB and 105 CHS. After filtering 20 outliers, the remaining 282 samples are classified into CHB and CHS at a threshold level of 0 for PC2. (PDF 165 kb)

Figure S4. Comparison of total SNV counts and the frequencies of specific base substitutions with the somatic statuses of certain genes. (a) The total SNV counts are compared to the somatic statuses of TP53, ZNF750, FAT1, FBXW7 and PIK3CA. (b) The frequencies of substitutions are compared to the somatic statuses of TP53. (c) The total SNV counts are compared to the somatic copy-number statuses of MYC, CDC27 and FHIT. (d) The frequency of Câ >â A substitution is compared to the somatic copy-number statuses of CDC27. FDR is based on the adjusted Wilcoxon rank-sum test P values. (PDF 418 kb)

// Ying Shi 1 , Guo-Bin Chen 1 , Xiao-Xiao Huang 1 , Chuan-Xing Xiao 1 , Huan-Huan Wang 1 , Ye-Sen Li 6,7 , Jin-Fang Zhang 4 , Shao Li 8 , Yin Xia 4,5 , Jian-Lin Ren 1 and Bayasi Guleng 1,2,3 1 Department of Gastroenterology, Zhongshan Hospital, Xiamen University, Xiamen, Fujian Province, China 2 Faculty of Clinical Medicine, Medical College, Xiamen University, Xiamen, Fujian Province, China 3 State Key Laboratory of Cellular Stress Biology, Xiamen University, Xiamen, Fujian Province, China 4 School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China 5 School of Biomedical Sciences Core Laboratory, The Chinese University of Hong Kong Shenzhen Research Institute, Shenzhen, China 6 Department of Nuclear Medicine, The First Affiliated Hospital of Xiamen University, Xiamen, Fujian Province, China 7 Center for Molecular Imaging and Translational Medicine, School of Public Health, Xiamen University, Xiamen, Fujian Province, China 8 MOE Key Laboratory of Bioinformatics, Tsinghua University, Beijing, China Correspondence to: Bayasi Guleng, email: // Jian-Lin Ren, email: // Yin Xia, email: // Keywords: dragon, colorectal cancer, BMP, Smad1/5/8, Erk1/2, proliferation Received : January 11, 2015 Accepted : April 21, 2015 Published : May 12, 2015 Abstract Colorectal cancer (CRC) is one of the most commonly diagnosed cancers and a major cause of cancer death. However, the molecular mechanisms underlying CRC initiation, growth and metastasis are poorly understood. Dragon (RGMb), a member of the repulsive guidance molecule (RGM) family, has been recently identified as a co-receptor for bone morphogenetic protein (BMP) signaling, but the role of Dragon in CRC development is undefined. Here, we show that Dragon expression was increased in colon cancer tissues compared to control tissues in CAC mouse model and in human patients. Dragon promoted proliferation of CT26.WT and CMT93 colon cancer cells and accelerated tumor growth in the xenograft mouse model. Dragon’s action on colon cancer development was mediated via the BMP4-Smad1/5/8 and Erk1/2 pathways. Therefore, our results have revealed that Dragon is a novel gene that promotes CRC growth through the BMP pathway. Dragon may be exploited as a potential therapeutic target for CRC treatment.

Gastric cancer (GC) is the second most frequent oncological cause of death, the fifth most common malignancy in the world, and accounts for 6.8% of all tumors. As an aggressive disease, GC is often diagnosed at an advanced stage, which is why it is a major cause of cancer-related death. In the last several decades, the incidence of GC has decreased, which should be credited to advances in diagnostic and therapeutic technologies including tumor-marker detection systems, imaging modalities, pathological methods, gastroscopy, and particularly surgical and pharmacologic interventions. Because they are economical, convenient, and noninvasive, the detection of conventional serum tumor biomarkers (e.g., CEA, CA19-9, and CA72-4) has been widely employed in the diagnosis and evaluation of GC. However, due to their poor specificity and sensitivity, these molecular markers cannot meet the demand of early GC detection. Hence, new and reliable tumor biomarkers are desperately needed. This review systematically summarizes the three most commonly used biomarkers of GC (e.g., CEA, CA19-9, and CA72-4) and addresses two categories of potential molecular biomarkers for the diagnosis of GC: microRNA and methylated DNA.

Mindin, a secreted, highly conserved extracellular matrix (ECM) protein, exerts a broad spectrum of effects on the innate immune system. However, its function in colorectal cancer (CRC) progression is not well established, and its upstream regulation mechanisms remain unclear. Contrary to previous reports, this study used two different enzyme-linked immunosorbent assay (ELISA) kits to show that the serum level of mindin was significantly decreased in CRC patients and that this decreased level is more significantly associated with the early stages of the disease. To explore the regulation of mindin, we used a bioinformatics approach to predict potential transcription factors and determined that early growth response factor (Egr)-1 directly regulates mindin expression at the transcriptional level using dual luciferase, chromatin immunoprecipitation (ChIP) DNA and electrophoretic mobility shift assay (EMSA) methods. Egr-1 regulates mindin mRNA and protein expression in CRC cells, and the protein expression of both Egr-1 and mindin was significantly decreased in tumor lesions of patients compared with adjacent control tissues. Mindin is essential for Egr-1-mediated inhibition of endothelial cell tube formation, and mindin inhibits endotheliocyte proliferation, migration and angiogenic sprouts in vitro. Overexpression of mindin suppressed xenograft tumor growth by blocking angiogenesis instead of directly suppressing CRC cell proliferation. Mechanically, mindin inhibits the hypoxia-induced HIF-1a and VEGFA protein expression in CRC cells and the phosphorylation of VEGFR-2 in endothelial cells. The results suggest that the serum level of mindin can be used as a novel biomarker for early detection of CRC and that the Egr-1/mindin axis is a potential therapeutic target for the inhibition of angiogenesis in CRC development.

Trefoil factor family 1 (TFF1) is a member of the TFF-domain peptide family involved in epithelial restitution and cell motility. Recently, we screened Piezo1 as a candidate TFF1-binding protein. We aimed to confirm Piezo1 as a novel TFF1 binding protein and to assess the role of this interaction in mediating gastric cancer cell mobility. This interaction was confirmed by co-immunoprecipitation and co-localisation of TFF1 and Piezo1 in GES-1 cells. We used stable RNA interference to knockdown Piezo1 protein expression and restored the expression of TFF1 in the gastric cancer cell lines SGC-7901 and BGC-823. Cell motility was evaluated using invasion assay and migration assay in vitro. The expression levels of the integrin subunits β1, β5, α1 as well as the expression of β-catenin and E-cadherin were detected by Western blot. We demonstrate that TFF1, but not TFF2 or TFF3, bind to and co-localize with Piezo1 in the cytoplasm in vitro. TFF1 interacts with the C-terminal portion of the Piezo1 protein. Wound healing and trans-well assays demonstrated that the restored expression of TFF1 promoted cell mobility in gastric cancer cells, and this effect was attenuated by the knockdown of Piezo1. Western blots demonstrated the decreased expression of integrin β1 in Piezo1-knockdown cells. Our data demonstrate that Piezo1 is a novel TFF1 binding protein that is important for TFF1-mediated cell migration and suggest that this interaction may be a therapeutic target in the invasion and metastasis of gastric cancer.

Chronic infection with hepatitis B virus is a cause of end-stage liver disease and hepatocellular carcinoma (HCC). We previously screened fructose-bisphosphate aldolase B (ALDOB) as a candidate binding protein of hepatitis B surface antigen (HBsAg) using a yeast 2-hybrid assay. In this study we aimed to confirm ALDOB as a binding protein of the S region of the HbsAg (HBs) and to investigate the function and involved mechanism between its interactions during HCC development. Our results demonstrated that both of exogenous and endogenous ALDOB proteins bind to HBs and colocalize in the cytoplasm in vitro. The coexistence of HBs and ALDOB inhibit apoptosis of cisplatin-induced HepG2 cells. Furthermore, western blot analysis showed the coexistence of HBs and ALDOB enhance the phosphorylations of AKT and its downstream of GSK-3β (phosphorylation); decreased expression of the pro-apoptotic proteins Bax, Bid, Bim, and Puma; and increased expression of the prosurvival proteins Bcl-2, Bcl-xl, and Mcl-1 in HepG2 cells. These findings suggest that interaction between HBs and ALDOB might be applied as a potential therapeutic target during the treatment of HBV-related hepatitis or HCC.

Background: Infection with the hepatitis B virus (HBV) is one of most important risk factors for hepatocellular carcinoma (HCC). Indeed, HBV is considered a group 1 human carcinogen and is a highly oncogenic agent. HBV cannot be effectively controlled or completely eliminated, so chronic HBV infection is a public health challenge worldwide. Summary: It is now believed that HBV-induced HCC involves a complex interaction between multiple viral and host factors. Many factors contribute to HBV-associated HCC, including products of HBV, viral integration and mutation, and host susceptibility. This review outlines the main pathogenic mechanisms with a focus on those that suggest novel targets for the prevention and treatment of HCC. Key Message: HBV infection is an important risk factor for HCC. Understanding the interaction between viral and host factors in HBV-induced HCC will reveal potential targets for future therapies. Practical Implications: The two main therapeutic strategies consist of antiviral agents and immunotherapy-based approaches. Dendritic cell-based immunotherapy is promising for restoring the T cell-mediated antiviral immune response. Another approach is the specific expansion of the host's pool of HBV-specific T cells. Stimulation of the Toll-like receptors (TLRs), particularly TLR9, provides another means of boosting the antiviral response. Combination therapy with cytokines (interferon gamma and tumor necrosis factor alpha) plus lamivudine is more effective than these agents used alone. Therapeutic vaccines are being developed as an alternative to long-term antiviral treatment or as an adjunct.

Peutz–Jeghers Syndrome (PJS) is an autosomal dominant disorder which predisposes to the development of various cancers. Germline mutation in the serine/threonine kinase 11 gene (STK11) is known as one of the major causes of PJS. However, a notable proportion of PJS samples do not carry any mutation in STK11, suggesting possible genetic heterogeneity in the disease and the existence of other causative variants. In order to identify other germline variants in the coding regions of the genome that are associated with PJS, we performed exome sequencing in three Chinese individuals with PJS and identified 16 common germline variants (12 protein-coding including STK11, 4 in pre-microRNAs). We further validated protein-coding variants in six PJS individuals (three with wild-type STK11) and predicted the functional impact. As result, we found that 7 coding variants are likely to have functional impacts. Especially, we identified 2 new germline variants which are represented in all six PJS samples and are independent of STK11 mutation. Our study provided an exomic view of PJS. The germline variants identified in our analysis may help to resolve the complex genetic background of the disease and thus lead to the discovery of novel causative variants of PJS.

Summary Circulatory antigens transit through the small intestine via the fenestrated capillaries in the lamina propria prior to entering into the draining lymphatics. But whether or how this process controls mucosal immune responses remains unknown. Here we demonstrate that dendritic cells (DCs) of the lamina propria can sample and process both circulatory and luminal antigens. Surprisingly, antigen cross-presentation by resident CX3CR1 + DCs induced differentiation of precursor cells into CD8 + T cells that expressed interleukin-10 (IL-10), IL-13, and IL-9 and could migrate into adjacent compartments. We conclude that lamina propria CX3CR1 + DCs facilitate the surveillance of circulatory antigens and act as a conduit for the processing of self- and intestinally absorbed antigens, leading to the induction of CD8 + T cells, that partake in the control of T cell activation during mucosal immune responses.

Trefoil factor family 2 (TFF2) participates in mucus stabilization and repair, apoptosis, and inflammatory responses. Previously published reports have indicated that several growth factors and basal transcription factors are associated with the expression of TFF2. However, the detailed mechanisms that regulate TFF2 expression are not fully understood. The present study was designed to assess the essential role of the transcription factor SP3 with respect to TFF2 expression. We first demonstrated that there was a negative correlation between the expression levels of SP3 and TFF2. Thus, in the examined cells, the overexpression of SP3 decreased the expression level of TFF2, whereas the inhibition of SP3 increased the expression level of TFF2. Moreover, we discovered two GC boxes in the TFF2 promoter and confirmed the specific binding of SP3 to this promoter. On the whole, this study indicated that Sp3 was a major regulator of TFF2 expression. This knowledge should contribute to our understanding of the role that is played by SP3 in the regulation of TFF2 expression.

Public Health Bureau of Xiamen in China [3502z20077038]; National Natural Science Foundation of China [30971362, 81072013]; Fundamental Research Funds for the Central Universities in China [2010111082]

Chronic inflammation, such as that seen in patients with inflammatory bowel disease (IBD), greatly increases the risk of developing colon cancer. Growing evidence supports a role for T cell-mediated immune response and release of various cytokines in the pathogenesis of colitis-associated cancer (CAC). In fact, CD4+ effector T cells promote chronic inflammation associated with IBD through release of proinflammatory cytokines, which leads to initiation and progression of colon cancer. Furthermore, CD8+ T cells reduce tumor growth through cancer immunosurveillance, which can also contribute to intestinal inflammation and thereby might promote tumor growth. In contrast, regulatory T cells (Tregs) release the immunosuppressive cytokines IL-10, TGF-β and thus have protective effects in CAC. In addition, dendritic cells (DCs) are important components of antitumor immunity. Recently, a novel mouse model that was associated with repeated inflammation was established for investigating the immunopathogenesis of CAC. This review discusses the role of T cell-mediated immune response, and DCs and involved cytokines in the immunopathogenesis of CAC in an animal model, which may also provide future therapeutic targets in CAC.

Genetic analysis has revealed a subset of recurrently mutated genes and aberrant cellular signaling pathways in hepatocellular carcinoma. To investigate genetic alterations and dysregulated pathways in hepatocellular carcinoma, we performed targeted sequencing and exome analysis using next-generation sequencer.We analyzed the somatic mutational profiles of 16 genes in primary hepatocellular carcinoma by targeted ultra-deep sequencing using nine pairs of specimens (tumor and peripheral blood) and whole-exome sequencing using one pair of samples.Overall, somatic mutations with high allele fraction were identified in tumor tissues by targeted deep sequencing. Somatic mutations with high allele fraction were observed in TP53 (3/9; 33%) and CTNNB1 (2/9; 22%) genes in five out of nine (55%) specimens. In vitro analysis showed that CTNNB1 H36P mutant protein identified in tumor samples was resistant to protein degradation and promoted cell proliferation. Exome sequencing identified SLIT3 mutation, implying that dysregulation of axon guidance genes is involved in the development of hepatocellular carcinoma. These results showed that TP53 and WNT/β-catenin signaling pathways were commonly mutated in hepatocellular carcinoma.These results suggest that targeted sequencing and exome sequencing enable the identification of putative oncogenic driver mutations during the development of hepatocarcinoma.

Purpose: It is important to identify the definitive molecular switches involved in the malignant transformation of premalignant tissues. Cellular senescence is a specific characteristic of precancerous tissues, but not of cancers, which might reflect tumorigenesis-protecting mechanisms in premalignant lesions. Polycomb protein Bmi1, which is a potent negative regulator of the p16INK4 gene, suppresses senescence in primary cells and is overexpressed in various cancers. We hypothesized that Bmi1 expression would also be dysregulated in precancerous lesions in human digestive precancerous tissues. Experimental Design: Bmi1 expression was investigated in cancerous and precancerous tissues of the digestive tract. The expression of p16, β-catenin, and Gli1 and the in vivo methylation status of the p16 gene were also analyzed in serial sections of colonic precancerous lesions. Results: Bmi1 was clearly overexpressed across a broad spectrum of gastrointestinal cancers, and the expression of Bmi1 increased in a manner that reflected the pathologic malignant features of precancerous colonic tissues (low-grade dysplasia, 12.9 ± 2.0%; high-grade dysplasia, 82.9 ± 1.6%; cancer, 87.5 ± 2.4%). p16 was also strongly expressed in high-grade dysplasia, but not in cancers. p16 promoter methylation was detected only in some Bmi1-positive neoplastic cells. Conclusions: Bmi1 overexpression was correlated with the malignant grades of human digestive precancerous tissues, which suggests that advanced Bmi1 dysregulation might predict malignant progression. The abnormal Bmi1 expression might link to malignant transformation via the disturbance of orderly histone modification.

The activation of Hedgehog (Hh) signaling has been implicated in the growth of various tumor types, including gastric carcinoma. However, the precise mechanisms of Hh activation and suppression of tumor growth by the blockade of Hh signaling in gastric carcinoma cells remain unknown. The aim of this study was to elucidate the mechanism of abnormal Hh signaling and the key molecules contributing to dysregulated growth of gastric carcinoma. The Sonic hedgehog (Shh) ligand and its receptor Patched were expressed in all five gastric carcinoma cell lines examined (MKN1, MKN7, MKN45, MKN74, and AGS cells). The blockade of Hh signaling with anti-Shh antibody inhibited the growth of all five gastric carcinoma cell lines. Shh was overexpressed (mean, 12.8-fold) in 8 of 14 (57.0%) cancerous tissue samples from patients with gastric carcinoma as compared with expression in the surrounding noncancerous tissues. The disruption of glioma-associated oncogene 1 (Gli1) by small interfering RNA induced an increase in p21/cyclin-dependent kinase–interacting protein 1 (CIP1), interfered with the G1-S transition, and suppressed cell proliferation. The stimulation or inhibition of Hh signaling did not affect p53 activity and the induction of p21/CIP1 expression and the G1 arrest by inhibition of Hh signaling were not affected by the p53 status. These findings suggest that the overexpression of Shh contributes to constitutive Hh activation and that this signaling pathway negatively regulates p21/CIP1 through a Gli1-dependent and p53-independent mechanism in gastric carcinoma cells.

The gastrointestinal tract is a major target of graft-versus-host disease (GVHD), which constitutes a life-threatening complication of bone marrow transplantation. GVHD is mainly caused by the activation of donor-derived lymphocytes, in which cytokine cascades play essential roles. Since p38 MAPK (p38) has been identified as a regulator of cytokine reactions and proposed as a molecular target for anti-inflammatory therapy, we investigated the contribution of p38 to the severity of murine intestinal GVHD. Unexpectedly, p38alpha(+/-) donor graft induced more acute GVHD-related mortality and more severe gut injury. The survival of p38alpha(+/-) donor-derived intestinal intraepithelial lymphocytes (IEL) was prolonged in vitro and in vivo, and TNF-alpha expression in the p38alpha(+/-) donor-derived IEL was also increased compared with wild-type cells. In contrast, the p38alpha(+/-) grafted mice resulted in decreased expansion of donor lymphocytes in mesenteric lymph nodes, and the up-regulation of IL-12p40 and IL-18 was diminished. These findings suggest that p38 has dichotomous effects for inflammatory response in vivo; not only regulates inflammatory cytokine expression and lymphocyte expansion, but also has distinct regulatory functions for IEL in intestinal GVHD. In conclusion, the inhibition of p38 may not be a suitable anti-inflammatory strategy for GVHD due to the associated intestinal injury.

Mutations in the B-raf gene have been reported in a number of human cancers, including melanoma and lung cancer. More than 80% of the reported B-raf mutations were V599E; however, non-V599E mutations have been frequently found in non-small cell lung cancers as compared with melanoma. Some non-V599E mutations have been found surrounding Thr439, which is thought likely to be one of the three Akt phosphorylation sites in the B-raf protein. However, as a previous report indicated that Thr439 was not phosphorylated by Akt, the functional consequences of these mutations have been unclear. Here, we examined the effects of cancer-related B-raf mutations surrounding Thr439 on the activation of the mitogen-activated protein/ extracellular signal-regulated kinase kinase (MEK)/extracellular signal-regulated kinase (Erk) pathway and the transformation of NIH 3T3 fibroblasts. Among the three reported mutations (K438Q, K438T, and T439P) found in non-small cell lung carcinoma and melanoma, none elevated the activity of the MEK/Erk cascade as determined by in vitro kinase assays, immunoblots using antibody specific for phosphorylated Erk, or Elk1-dependent reporter assays. The inhibition of phosphatidylinositol 3-kinase (PI3K)/Akt signaling by LY294002 increased the Erk activation induced by the mutant B-raf proteins, as well as by wild-type B-raf. Furthermore, the B-raf mutants did not have increased NIH 3T3-transforming activities, as determined by colony-formation assays. These results suggest that the B-raf mutations surrounding Thr439 found in human cancers are unlikely to contribute to increased oncogenic properties of B-raf.

Previous studies have highlighted the role of genetic predispositions in disease and several genes had been identified as important in Crohn’s disease (CD). However, many of these genes are likely rare and not associated with susceptibility in Chinese CD patients. We found 294 shared identical variants in the CD patients of which 26 were validated by Sanger sequencing. Two heterozygous IFN variants (IFNA10 c.60 T > A; IFNA4 c.60 A > T) were identified as significantly associated with CD susceptibility. The single-nucleotide changes alter a cysteine situated before the signal peptide cleavage site to a stop code (TGA) in IFNA10 result in the serum levels of IFNA10 were significantly decreased in the CD patients compared to the controls. Furthermore, the IFNA10 and IFNA4 mutants resulted in an impairment of the suppression of HCV RNA replication in HuH7 cells and the administration of the recombinant IFN subtypes restored DSS-induced colonic inflammation through the upregulation of CD4+ Treg cells. We identified heterozygous IFNA10 and IFNA4 variants as a cause of impaired function and CD susceptibility genes in Chinese patients from multiple center based study. These findings might provide clues in the understanding of the genetic heterogeneity of CD and lead to better screening and improved treatment.

Tyrosine kinases, which are important regulators of intracellular signal-transduction pathways, have mutated forms that are often associated with oncogenesis and are attractive targets for therapeutic intervention. Recently, systematic mutational analyses of tyrosine kinases revealed that a minimum of 30% of colorectal cancer contain at least one mutation in the tyrosine kinases. To further explore these mutations, we examined all reported mutations of NTRK3, FES, KDR, EPHA3, NTRK2, JAK1, PDGFRA, EPHA7, EPHA8, ERBB4, FGFR1, MLK4 and GUCY2F genes in the 24 colorectal cancer cell lines. Unexpectedly, among 24 colorectal cancer cell lines, only two cell lines (LoVo and CaR1) harbored mutation C1408T (R470C) in MLK4 gene. The mutation rate was extremely low compared to that previously reported. Therefore, we analyzed mutations in 46 colorectal cancer samples resected from the same number of Japanese patients. Surprisingly, none of the 46 samples contained any of the mutations reported. Based on our study, we advise that a more comprehensive tyrosine kinase gene mutation assay is necessary in the future.

A recent study revealed that the p110alpha (PIK3CA), catalytic subunit of phosphatidylinositol 3-kinase (PI3K), is somatically mutated in many types of cancer. For example, PIK3CA is mutated in an estimated 35.6% of hepatocellular carcinoma (HCC) cases. To measure the frequency of PIK3CA hotspot mutations in Japanese HCC patients, exons 9 and 20 of the PIK3CA gene were sequenced in 47 clinical HCC samples. Contrary to expectations, no hotspot mutations were found any of the HCC samples. In addition, we found abnormally migrating waves near the end of exon 9 in the PCR chromatograms from 13 of the 47 samples. PCR amplification and subsequent cloning and sequencing revealed that these chromatograms contained two distinct sequences, the wild-type p110alpha sequence and a different sequence found on human chromosome 22q11.2, the Cat Eye Syndrome region, which contains a putative pseudogene of PIK3CA. These abnormally migrating waves were also found in noncancerous liver tissue, indicating that this was not a result of HCC-associated mutations. Therefore, it is likely that the percentage of hotspot mutations in the PIK3CA gene of Japanese HCC patients is lower than was previously reported.

The role of Pokemon (POK erythroid myeloid ontogenic actor), a recently identified POK transcription factor with proto-oncogenic activity, in hepatocellular carcinogenesis has only been assessed by a few studies. Our previous study revealed that Pokemon is overexpressed in hepatocellular carcinomas (HCC) and promotes HCC cell proliferation and migration via an AKT- and ERK- dependent manner. In the present study, we used the TUNEL assay and FACS analysis to demonstrate that oxaliplatin induced apoptosis was significantly increased in cells with silenced Pokemon. Western blots showed that p53 expression and phosphorylation were significantly increased in Pokemon defective cells, thereby initiating the mitochondria-mediated and death receptor-mediated apoptotic pathways. In the mitochondria-mediated pathway, expression of pro-apoptotic Bcl-2 family members (including Bad, Bid, Bim and Puma) as well as AIF was increased and decreasing the mitochondrial membrane potential resulted in cytochrome C released from mitochondrial in HepG2 si-Pokemon cells. In addition, upon oxaliplatin treatment of Pokemon-silenced cells, the FAS receptor, FADD and their downstream targets caspase-10 and caspase-8 were activated, causing increased release of caspase-8 active fragments p18 and p10. Increased activated caspase-8-mediated cleavage and activation of downstream effector caspases such as caspase-9 and caspase-3 was observed in HepG2 si-Pokemon cells as compared to control. Therefore, Pokemon might serve as an important mediator of crosstalk between intrinsic and extrinsic apoptotic pathways in HCC cells. Moreover, our findings suggest that Pokemon could be an attractive therapeutic target gene for human cancer therapy.

Inflammatory bowel disease (IBD) can lead to an increased risk of developing colorectal cancer (CRC). The aim of this study was to establish a model for combined bone marrow transplantation (BMT) and colitis-associated colorectal cancer (CAC) and to define the contribution of BM-derived cells during the inflammation associated with carcinogenesis. We established a model for BMT using green fluorescent protein (GFP) transgenic mice, followed by AOM/DSS-induced CAC, and performed confocal microscopy analysis on in vivo living tissue and frozen tumor sections. Our imaging analyses showed that GFP-positive cells extensively infiltrated the tumor stroma and that some WGA and GFP or CD31 and GFP double-positive cells were observed in the lining of tumor vessels. Flow cytometry analysis of the tumor-infiltrating cells showed that the GFP-positive CD11c+ DCs cells were one-third of the GFP+/CD11C- cells, and that half of these DCs (0.96% vs 1.02%) were GFP-positive BM-derived cells. The majority of CD4(+) T cells were GFP-negative (12.02% vs 1.9%), and we discovered a novel CD4(+) CD11c(+) DC subset (0.34% vs 1.64%). In conclusion, we defined the distribution of BM-derived endothelial cells, CD11c(+) DCs and CD4(+) T cells in tumors. This model might be useful for elucidating the diverse BM-derived cell types and functions during the progression of colitis-associated colorectal cancer.

Leptospirosis is a reemerging zoonosis of global importance. Outbreaks are related to agricultural environments and exposure to flooding, and it is primarily found in tropical countries. Although cases with typical presentation are relatively easy to diagnose and treat, atypical cases make it difficult to differentiate from other diseases, especially those patients with digestive symptoms who present to departments of gastroenterology. A 54-year old man was admitted to hospital for jaundice, vomiting and fatty liver. leptospirosis antibody test and polymerase chain reaction did not help us to make a definite diagnosis. However, based on the patient’s presentation, physical characteristics and the muscular biopsy, Weil’s syndrome was diagnosed. This is a reminder that leptospirosis may be found in a developed city of southern China. Clinical experience, disease characterizations, physical signs and biopsy should be applied as more efficient ways to recognize atypical cases of leptospirosis.