Berberine ameliorates nonalcoholic fatty liver disease-induced bone loss by inhibiting ferroptosis.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) may contribute to osteoporosis. Berberine is a traditional Chinese medicine and was recently shown to be beneficial in NAFLD. However, little is known about its impact on bone loss induced by NAFLD. AIM: We aimed to explore the role of berberine in bone loss and determine its underlying mechanisms in NAFLD. METHODS: C57BL/6 mice were fed a high-fat high-fructose high-glucose diet (HFFGD) for 16 weeks to establish a NAFLD mouse model. The mice were administered berberine (300 mg/kg/d) by gavage, and fatty liver levels and bone loss indicators were tested. RESULTS: Berberine significantly improved HFFGD-induced weight gain, hepatic lipid accumulation and increases in serum liver enzymes, thereby alleviating NAFLD. Berberine increased trabecular number (Tb. N), trabecular thickness (Tb. Th), bone volume to tissue volume ratio (BV/TV), and decreased trabecular separation (Tb. Sp) and restored bone loss in NAFLD. Mechanistically, berberine significantly inhibited ferroptosis and 4-hydroxynonenal (4-HNE), prostaglandin-endoperoxide synthase 2 (PTGS2), and transferrin (TF) levels and increased ferritin heavy chain (FTH) levels in the femurs of HFFGD-fed mice. Moreover, berberine also activated the solute carrier family 7 member 11 (SLC7A11)/glutathione (GSH)/glutathione peroxidase 4 (GPX4) signaling pathway. CONCLUSION: Berberine significantly ameliorates bone loss induced by NAFLD by activating the SLC7A11/GSH/GPX4 signaling pathway and inhibiting ferroptosis. Therefore, berberine may serve as a therapeutic agent for NAFLD-induced bone loss.

Development and validation of metabolic models for predicting survival and immune status of hepatocellular carcinoma patients.

BACKGROUND: Metabolic reprogramming is associated with the carcinogenesis of hepatocellular carcinoma (HCC). The effects of metabolism-related genes on predicting survival and immune status in HCC remain unclear. OBJECTIVES: To develop and validate metabolic models for predicting the survival and immune status of HCC patients. MATERIAL AND METHODS: The metabolic core genes for overall survival (OS) and disease-free survival (DFS) were retrieved. Then, glycolysis and fatty acid metabolism prognostic models were constructed and validated using The Cancer Genome Atlas (TCGA) and the International Cancer Genome Consortium (ICGC) data. Decision trees based on machine learning were developed for classifying the prognostic risks of HCC patients. The associations between the metabolic signatures, immunotherapy and immune cell infiltration were investigated. Experimental validations were performed using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry (IHC). RESULTS: We identified 30 prognostic core genes for glycolysis metabolism and 12 prognostic core genes for fatty acid metabolism. Subsequently, 2 glycolysis models and 2 fatty acid metabolism models were developed to predict the OS and DFS of HCC patients, respectively. Two decision trees were constructed to classify the low-, intermediateand high-risk groups of HCC patients for OS and DFS. Moreover, the patients in the high-risk groups of glycolysis and fatty acid metabolic models tended to have higher expression of programmed cell death ligand-1 (PD-L1 or CD274), programmed cell death 1 (PDCD1), cytotoxic T-lymphocyte-associated protein-4 (CTLA-4), and lymphocyte activating 3 (LAG3). Most of the metabolic core genes were significantly associated with immune cell infiltration. In addition, ATP-binding cassette subfamily B member 6 (ABCB6), peptidylprolyl isomerase A (PPIA), uroporphyrinogen decarboxylase (UROD), and non-SMC condensin II complex subunit H2 (NCAPH2) were positively correlated with both tumor mutational burden (TMB) and microsatellite instability (MSI) scores. The expression of ABCB6, PPIA, UROD, and NCAPH2 was validated using RT-qPCR and IHC. CONCLUSIONS: We established novel prognostic models based on metabolism-related genes to better predict the outcome and immune status of HCC patients.

Ruxolitinib Alleviates Inflammation, Apoptosis, and Intestinal Barrier Leakage in Ulcerative Colitis via STAT3.

BACKGROUND: Ulcerative colitis (UC) is an idiopathic, chronic inflammatory disorder of the colonic mucosa with increasing prevalence and limited management. Ruxolitinib is a new anti- JAK/STAT3 biologic agent that has shown potential in protecting against colitis. METHODS: We first constructed an in vivo UC model and an in vitro colonic epithelial cell inflammation model. Ruxolitinib was administered via gavage in mice. After treatment, colon tissues, cells, and cell lysates were collected and prepared for histological evaluation, immunohistochemistry, immunofluorescence staining, quantitative reverse-transcriptase polymerase chain reaction, Western blotting, terminal deoxynucleotidyl transferase mediated dUTP nick end labeling staining, and cytokine analysis. STAT3 expression was silenced and overexpressed via small interfering RNA and overexpression plasmid transfection, respectively, and quantitative reverse-transcriptase polymerase chain reaction was used to examine the downstream effects. RESULTS: Ruxolitinib administration significantly alleviated colitis both in vivo and in vitro, as manifested by reduced body weight loss, shortened colon lengths, relieved disease activity (measured by the disease activity index), and prolonged survival. A mechanistic study showed that ruxolitinib attenuated nuclear factor kappa B-induced inflammation, reduced apoptosis, and ameliorated epithelial barrier leakage, and thereby reduced colitis activity in vivo. STAT3 knockdown partially reversed the protective effect of ruxolitinib against colitis, while STAT3 overexpression exaggerated the reductions in proinflammatory cytokine levels upon ruxolitinib treatment. CONCLUSIONS: We demonstrate that ruxolitinib alleviates colitis by inhibiting nuclear factor kappa B-related inflammation and apoptosis in addition to restoring epithelial barrier function via STAT3, providing a new strategy for UC treatment.

We studied the effect and mechanism of ruxolitinib on ulcerative colitis. We discovered that ruxolitinib administration significantly alleviated murine colitis by relieving disease activity and prolonged survival through intestinal epithelial cell nuclear factor kappa B­induced inflammation, reduced apoptosis, and ameliorated epithelial barrier leakage via STAT3.

Tumor budding as an indicator for lymph node metastasis and prognosis of early gastric cancer.

BACKGROUND: Tumor budding, considered as an independent risk factor reflecting prognosis of some malignant tumors, has been recognized as an important clinicopathological indicator of colorectal carcinoma. However, the evaluation of tumor budding and its clinicopathological significance in gastric cancer remain controversial. AIM: To investigate the relationship between tumor budding and clinical biological behavior of early gastric cancer (EGC) and assess the predictive value of tumor budding for lymph node metastasis as well as its impact on prognosis of EGC patients. METHODS: Tissue specimens of 164 EGC patients who underwent radical gastrectomy between June 2011 and January 2017 from a single center were selected to carry out HE and CK staining respectively, so as to evaluate tumor budding under light microscopy. Clinicopathological data and follow-up results of all EGC patients were collected for statistical analysis among tumor budding, EGC clinicopathological factors and prognosis. RESULTS: Of all 164 EGC patients, there were 84 (51.2%) cases with mucosal invasion and 80 (48.8%) cases with submucosal invasion. Meanwhile, 32 cases (19.5%) had lymph node metastasis, 19 (11.6%) had lympho-vascular invasion and 4 (2.4%) had early recurrence. Tumor budding were observed in 90 (54.9%) patients, with low-grade budding 68 (41.5%) cases and high-grade budding 22 (13.4%) cases. Tumor budding was closely correlated with tumor size (c2 = 6.609, P = 0.037), tumor histologic differentiation (c2 = 10.522, P = 0.032), depth of invasion (c2 = 8.787, P = 0.012), lymph node metastasis (c2 = 24.226, P < 0.01), TNM stage (c2 = 24.226, P < 0.01), lympho-vascular invasion (c2 = 8.225, P = 0.016) and early recurrence (c2 = 6.462, P = 0.040). Additionally, tumor budding was correlated with postoperative survival rate as well. Multiple regression analysis revealed that tumor budding was an independent influencing factor of postoperative 3-year survival rate, 5-year survival rate, OS, DFS and DSS (P < 0.05). Furthermore, tumor budding was an independent risk factor of lymph node metastasis of EGC patients, and high-grade budding was a high-risk indicator of lymph node metastasis. CONCLUSION: Tumor budding is related to tumor size, tumor histologic differentiation, depth of invasion, lymph node metastasis, lympho-vascular invasion and early recurrence of EGC. Tumor budding, especially high-grade budding can serve as an indicator for predicting lymph node metastasis of EGC, and high-grade budding could be an important parameter for evaluating prognosis of EGC patients.

Resveratrol synergizes with cisplatin in antineoplastic effects against AGS gastric cancer cells by inducing endoplasmic reticulum stress­mediated apoptosis and G2/M phase arrest.

Gastric cancer (GC) is a common gastrointestinal malignancy, and cisplatin (DDP) is an important component of chemotherapeutic regimens for GC. However, the application of DDP is limited by its dose­dependent systemic toxicity. Resveratrol (RES) is a natural polyphenol compound that has chemopreventive and therapeutic effects against various cancers, including GC. However, whether RES can sensitize GC cells to DDP remains unknown. Following RES/DDP combination treatment, cell viability was determined by Cell Counting Kit­8 and colony­forming assays, and cell apoptosis and the cell cycle were detected by FITC­Annexin V/PI staining assay and PI staining assay, respectively, followed by flow cytometry. Moreover, western blotting was performed to evaluate the protein expression levels, and the intracellular free Ca2+ concentration was determined by a Fluo­4 AM probe after cell cotreatment with RES and DDP. The present results demonstrated that RES/DDP combination treatment significantly inhibited cell viability, promoted cell apoptosis and induced G2/M phase arrest in AGS cells. In addition, it was determined that RES combined with DDP significantly increased the levels of Bax, cleaved poly­ADP­ribose polymerase (PARP), glucose­regulated protein 78 (GRP78), PRKR­like ER kinase (PERK), p­eukaryotic translation initiation factor 2α (p­eIF2α), CCAAT/enhancer binding protein homologous protein (CHOP) and cleaved caspase­12, whereas Bcl­2 expression was downregulated following RES/DDP cotreatment. Moreover, RES/DDP cotreatment significantly upregulated phosphorylated cyclin­dependent kinase 1 (p­CDK1, Tyr15), p21Waf1/Cip1 and p27Kip1 protein levels and downregulated Cdc25C protein levels. In conclusion, RES and DDP synergistically inhibited the growth of the gastric adenocarcinoma cell line AGS by inducing endoplasmic reticulum stress­mediated apoptosis and G2/M phase arrest via activation of the PERK/eIF2α/activating transcription factor 4 (ATF4)/CHOP signaling pathway and caspase­12 and by inactivating the CDK1­cyclin B1 complex. These results indicated that RES is a promising adjuvant for DDP during GC chemotherapy.

Blockage of ETS homologous factor inhibits the proliferation and invasion of gastric cancer cells through the c-Met pathway.

BACKGROUND: Gastric cancer (GC) is one of the most common and deadliest types of cancer worldwide due to its delayed diagnosis and high metastatic frequency, but its exact pathogenesis has not been fully elucidated. ETS homologous factor (EHF) is an important member of the ETS family and contributes to the pathogenesis of multiple malignant tumors. To date, whether EHF participates in the development of GC via the c-Met signaling pathway remains unclear. AIM: To investigate the role and mechanism of EHF in the occurrence and development of GC. METHODS: The expression of EHF mRNA in GC tissues and cell lines was measured by quantitative PCR. Western blotting was performed to determine the protein expression of EHF, c-Met, and its downstream signal molecules. The EHF expression in GC tissues was further detected by immunohistochemical staining. To investigate the role of EHF in GC oncogenesis, small interfering RNA (siRNA) against EHF was transfected into GC cells. The cell proliferation of GC cells was determined by Cell Counting Kit-8 and colony formation assays. Flow cytometry was performed following Annexin V/propidium iodide (PI) to identify apoptotic cells and PI staining to analyze the cell cycle. Cell migration and invasion were assessed by transwell assays. RESULTS: The data showed that EHF was upregulated in GC tissues and cell lines in which increased expression of c-Met was also observed. Silencing of EHF by siRNA reduced the proliferation of GC cells. Inhibition of EHF induced significant apoptosis and cell cycle arrest in GC cells. Cell migration and invasion were significantly inhibited. EHF silencing led to c-Met downregulation and further blocked the Ras/c-Raf/extracellular signal-related kinase 1/2 (Erk1/2) pathway. Additionally, phosphatase and tensin homolog was upregulated and glycogen synthase kinase 3 beta was deactivated. Moreover, inactivation of signal transducer and activator of transcription 3 was detected following EHF inhibition, leading to inhibition of the epithelial-to-mesenchymal transition (EMT). CONCLUSION: These results suggest that EHF plays a key role in cell proliferation, invasion, apoptosis, the cell cycle and EMT via the c-Met pathway. Therefore, EHF may serve as an antineoplastic target for the diagnosis and treatment of GC.

Sirtuin 1 alleviates endoplasmic reticulum stress-mediated apoptosis of intestinal epithelial cells in ulcerative colitis.

BACKGROUND: Sirtuin 1 (SIRT1) is a nicotinamide adenine dinucleotide (NAD+)-dependent protein deacetylase that is involved in various diseases, including cancers, metabolic diseases, and inflammation-associated diseases. However, the role of SIRT1 in ulcerative colitis (UC) is still confusing. AIM: To investigate the role of SIRT1 in intestinal epithelial cells (IECs) in UC and further explore the underlying mechanisms. METHODS: We developed a coculture model using macrophages and Caco-2 cells. After treatment with the SIRT1 activator SRT1720 or inhibitor nicotinamide (NAM), the expression of occludin and zona occludens 1 (ZO-1) was assessed by Western blot analysis. Annexin V-APC/7-AAD assays were performed to evaluate Caco-2 apoptosis. Dextran sodium sulfate (DSS)-induced colitis mice were exposed to SRT1720 or NAM for 7 d. Transferase-mediated dUTP nick-end labeling (TUNEL) assays were conducted to assess apoptosis in colon tissues. The expression levels of glucose-regulated protein 78 (GRP78), CCAAT/enhancer-binding protein homologous protein (CHOP), caspase-12, caspase-9, and caspase-3 in Caco-2 cells and the colon tissues of treated mice were examined by quantitative real-time PCR and Western blot. RESULTS: SRT1720 treatment increased the protein levels of occludin and ZO-1 and inhibited Caco-2 apoptosis, whereas NAM administration caused the opposite effects. DSS-induced colitis mice treated with SRT1720 had a lower disease activity index (P < 0.01), histological score (P < 0.001), inflammatory cytokine levels (P < 0.01), and apoptotic cell rate (P < 0.01), while exposure to NAM caused the opposite effects. Moreover, SIRT1 activation reduced the expression levels of GRP78, CHOP, cleaved caspase-12, cleaved caspase-9, and cleaved caspase-3 in Caco-2 cells and the colon tissues of treated mice. CONCLUSION: SIRT1 activation reduces apoptosis of IECs via the suppression of endoplasmic reticulum stress-mediated apoptosis-associated molecules CHOP and caspase-12. SIRT1 activation may be a potential therapeutic strategy for UC.

Sigmoid colon translocation of an intrauterine device misdiagnosed as a colonic polyp: A case report.

RATIONALE: Intrauterine contraceptive devices (IUDs) are recommended as a means of contraception. Translocation of IUD is a rare and serious complication. Colonic inflammatory mass caused by translocated IUD initially misdiagnosed as a colonic polyp is extremely rare and has not been reported yet. PATIENT CONCERNS: This report presents a case of sigmoid colon translocation of intrauterine device on a 37-year-old female patient. Colonoscopy was performed due to her complain of repeated blood in stools and subsequently the patient was misdiagnosed as a sigmoid colon polyp. Nonetheless, the "polyp" was not able to be removed endoscopically. DIAGNOSES: Sigmoid colon translocation of an intrauterine device. INTERVENTIONS: To further clarify the diagnosis, computed tomography (CT) scan was performed and the "polyp" was confirmed to be caused by a translocated IUD. OUTCOMES: The translocated IUD was removed easily by surgery, and the patient recovered soon after the operation. LESSONS: The present case indicates that an annual gynaecologic examination is necessary to determine the position of the IUD, and a CT examination may help confirm an ectopic IUD.

Histone acetyltransferase p300/CBP inhibitor C646 blocks the survival and invasion pathways of gastric cancer cell lines.

The histone acetyltransferases (HATs) adenovirus E1A-associated protein (p300) and CREB binding protein (CBP) serve as coactivators during a diverse assortment of cellular processes. In the present study, p300 and CBP were highly expressed in 5 gastric cancer (GC) cell lines (SGC­7901, MKN45, MGC-803, BGC-823 and KATO III) compared with human normal gastric epithelial cell line (GES-1). C646, a selective inhibitor of p300 and CBP, inhibited cell viability and cell cycle and promoted cell apoptosis in all 5 GC cell lines. In addition, C646 suppressed the migration and invasion capability of the GC cell lines, except for the middle-differentiated SGC-7901 cell line. Furthermore, we detected the differential expression of corresponding oncogenic signalling molecules, such as c-Met, Akt, Bcl-2, Bax, cyclin D1, MMP7 and MMP9, in GC cells following C646 treatment. In conclusion, our results suggest that C646 inhibits the acetylation of histone H3 via inactivation of p300 and CBP, resulting in antineoplastic effects toward GC cells. Thus, the selective HAT inhibitor C646 could be a promising antitumour reagent for GC treatment.

Emodin alleviates intestinal mucosal injury in rats with severe acute pancreatitis via the caspase-1 inhibition.

BACKGROUND: Emodin, a traditional Chinese medicine, has a therapeutic effect on severe acute pancreatitis (SAP), whereas the underlying mechanism is still unclear. Studies showed that the intestinal mucosa impairment, and subsequent release of endotoxin and proinflammatory cytokines such as IL-1ß, which further leads to the dysfunction of multiple organs, is the potentially lethal mechanism of SAP. Caspase-1, an IL-1ß-converting enzyme, plays an important role in this cytokine cascade process. Investigation of the effect of emodin on regulating the caspase-1 expression and the release proinflammatory cytokines will help to reveal mechanism of emodin in treating SAP. METHODS: Eighty Sprague-Dawley rats were randomly divided into four groups (n=20 each group): SAP, sham-operated (SO), emodin-treated (EM) and caspase-1 inhibitor-treated (ICE-I) groups. SAP was induced by retrograde infusion of 3.5% sodium taurocholate into the pancreatic duct. Emodin and caspase-1 inhibitor were given 30 minutes before and 12 hours after SAP induction. Serum levels of IL-1ß, IL-18 and endotoxin, histopathological alteration of pancreas tissues, intestinal mucosa, and the intestinal caspase-1 mRNA and protein expressions were assessed 24 hours after SAP induction. RESULTS: Rats in the SAP group had higher serum levels of IL-1ß and IL-18 (P<0.05), pancreatic and gut pathological scores (P<0.05), and caspase-1 mRNA and protein expressions (P<0.05) compared with the SO group. Compared with the SAP group, rats in the EM and ICE-I groups had lower IL-1ß and IL-18 levels (P<0.05), lower pancreatic and gut pathological scores (P<0.05), and decreased expression of intestine caspase-1 mRNA (P<0.05). Ultrastructural analysis by transmission electron microscopy found that rats in the SAP group had vaguer epithelial junctions, more disappeared intercellular joints, and more damaged intracellular organelles compared with those in the SO group or the EM and ICE-I groups. CONCLUSIONS: Emodin alleviated pancreatic and intestinal mucosa injury in experimental SAP. Its mechanism may partly be mediated by the inhibition of caspase-1 and its downstream inflammatory cytokines, including IL-1ß and IL-18. Our animal data may be applicable in clinical practice.

Systematic review with network meta-analysis: dual therapy for high-risk bleeding peptic ulcers.

BACKGROUND: Adding a second endoscopic therapy to epinephrine injection might improve hemostatic efficacy in patients with high-risk bleeding ulcers but the optimum modality remains unknown. We aimed to estimate the comparative efficacy of different dual endoscopic therapies for the management of bleeding peptic ulcers through random-effects Bayesian network meta-analysis. METHODS: Different databases were searched for controlled trials comparing dual therapy versus epinephrine monotherapy or epinephrine combined with another second modality until September, 30 2016. We estimated the ORs for rebleeding, surgery and mortality among different treatments. Adverse events were also evaluated. RESULTS: Seventeen eligible articles were included in the network meta-analysis. The addition of mechanical therapy (OR 0.19, 95% CrI 0.07-0.52 and OR 0.10, 95% CrI 0.01-0.50, respectively) after epinephrine injection significantly reduced the probability of rebleeding and surgery. Similarly, patients who received epinephrine plus thermal therapy showed a significantly decreased rebleeding rate (OR 0.30, 95% CrI 0.10-0.91), as well as a non-significant reduction in surgery (OR 0.47, 95% CrI 0.16-1.20). Although differing, epinephrine plus mechanical therapy did not provide a significant reduction in rebleeding (OR 0.62, 95% CrI 0.19-2.22) and surgery (OR 0.21, 95% CrI 0.03-1.73) compared to epinephrine plus thermal therapy. Sclerosant failed to confer further benefits and was ranked highest among the 5 treatments in relation to adverse events. CONCLUSIONS: Mechanical therapy was the most appropriate modality to add to epinephrine injection. Epinephrine plus thermal coagulation was effective for controlling high risk bleeding ulcers. There was no further benefit with sclerosants with regard to rebleeding or surgery, and sclerosants were also associated with more adverse events than any other modality.

An inhibitor of the acetyltransferases CBP/p300 exerts antineoplastic effects on gastrointestinal stromal tumor cells.

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasm featured by activated mutations of KIT and PDGFRA. Although overall survival rates have greatly improved by the development of receptor tyrosine kinase inhibitors, most patients ultimately acquire resistance due to secondary mutations of KIT or PDGFRA. Inhibition of the histone acetyltransferases (HATs) CREB­binding protein (CBP) and p300 results in antineoplastic effects in various cancers. To determine whether CBP/p300 can serve as an antineoplastic target for GISTs, specific short interfering RNA sequences and the selective HAT inhibitor C646 were administered to GIST882 cells. Cell viability, apoptosis and the cell cycle were analysed using the Cell Counting Kit-8, a caspase-3/7 activity assay or Annexin V-fluorescein isothiocyanate/propidium iodide (PI) staining and PI staining. Gene and protein expression levels were measured by quantitative real-time polymerase chain reaction and western blotting, respectively. Transcriptional blockage of CBP, rather than p300, resulted in suppression of cell proliferation. Interestingly, both CBP and p300 depletion enhanced caspase-3/7 activity. A lack of CBP and p300 caused ETS translocation variant 1 (ETV1) downregulation and KIT inhibition in GIST cells. Nevertheless, the absence of CBP, not p300, leads to extracellular signal-regulated kinase 1/2 inactivation and c-Jun NH2-terminal kinase activation, suggesting a more crucial role for CBP than p300 in cell proliferation and survival. Furthermore, proliferation of GIST cells was reduced by administration of C646, a selective HAT inhibitor for CBP/p300. Apoptosis induction and cell cycle arrest were detected after exposure to C646, indicating that its antitumor activities were supported by its antiproliferative and proapoptotic effects. Additionally, C646 treatment attenuated ETV1 protein expression and inactivated KIT-dependent pathways. Taken together, the present study suggests that CBP/p300 may serve as novel antineoplastic targets and that use of the selective HAT inhibitor C646 is a promising antitumor strategy for GISTs.

Succinate dehydrogenase-deficient gastrointestinal stromal tumors.

Most gastrointestinal stromal tumors (GISTs) are characterized by KIT or platelet-derived growth factor alpha (PDGFRA) activating mutations. However, there are still 10%-15% of GISTs lacking KIT and PDGFRA mutations, called wild-type GISTs (WT GISTs). Among these so-called WT GISTs, a small subset is associated with succinate dehydrogenase (SDH) deficiency, known as SDH-deficient GISTs. In addition, GISTs that occur in Carney triad and Carney-Stratakis syndrome represent specific examples of SDH-deficient GISTs. SDH-deficient GISTs locate exclusively in the stomach, showing predilection for children and young adults with female preponderance. The tumor generally pursues an indolent course and exhibits primary resistance to imatinib therapy in most cases. Loss of succinate dehydrogenase subunit B expression and overexpression of insulin-like growth factor 1 receptor (IGF1R) are common features of SDH-deficient GISTs. In WT GISTs without succinate dehydrogenase activity, upregulation of hypoxia-inducible factor 1α may lead to increased growth signaling through IGF1R and vascular endothelial growth factor receptor (VEGFR). As a result, IGF1R and VEGFR are promising to be the novel therapeutic targets of GISTs. This review will update the current knowledge on characteristics of SDH-deficient GISTs and further discuss the possible mechanisms of tumorigenesis and clinical management of SDH-deficient GISTs.

Rabeprazole exhibits antiproliferative effects on human gastric cancer cell lines.

Intracellular proton extrusion in gastric cancer cells has been reported to promote cancer cell survival under acidic conditions via hydrogen/potassium adenosine triphosphatase (H+/K+-ATPase). Rabeprazole is a frequently used second-generation proton pump inhibitor (PPI) that irreversibly inactivates gastric H+/K+-ATPase. Therefore, we hypothesized that rabeprazole could reduce the viability of gastric cancer cells. In the present study, four human gastric cancer cell lines and one non-cancer gastric cell line were cultured. Cell viability, the α- and ß-subunits of H+/K+-ATPase and cellular apoptosis were analyzed by dye exclusion assay, reverse transcription-polymerase chain reaction and annexin V-fluorescein isothiocyanate/propidium iodide staining, respectively. The expression level of total extracellular signal-regulated protein kinase 1/2 (ERK 1/2) and phosphorylated-ERK protein was detected by western blot analysis. Gastric cancer cell lines were more tolerant of the acidic culture media than non-cancer cells. Administration of rabeprazole led to a marked decrease in the viability of MKN-28 cells. Exposure to rabeprazole induced significant apoptosis in AGS cells. Rabeprazole completely inhibited the phosphorylation of ERK 1/2 in the MKN-28 cells, whereas the same effect was not observed in either the KATO III or MKN-45 cells. The ERK 1/2 inhibitor, PD98059, attenuated the viability of the AGS cells. A similar antiproliferative effect was observed in the rabeprazole treatment group. In addition, PD98059 and rabeprazole were able to efficaciously inhibit the phosphorylation of ERK 1/2 in the gastric cancer cells. Therefore, it was concluded that rabeprazole can attenuate the cell viability of human gastric cancer cells through inactivation of the ERK1/2 signaling pathway. The results of the present study demonstrate that rabeprazole inhibits the viability of gastric cancer cells in vitro and may serve as a novel antineoplastic agent.

Altered expression of ETV1 and its contribution to tumorigenic phenotypes in gastrointestinal stromal tumors.

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal neoplasm of the gastrointestinal tract. ETV1 is a unique transcription factor specific to GIST that has been reported to date. The present study aimed to determine aberrant ETV1 expression and its contribution to tumorigenesis in GISTs. Altered expression levels of ETV1 and its relevant signaling pathways were assessed using western blotting and quantitative real-time PCR in 72 paired patient tissue samples. In addition, immunochemistry was performed on 156 GISTs using tissue microarray to analyze the correlation between ETV1 and clinical parameters. The results revealed that ETV1 was highly expressed in the GISTs at both the transcription and protein levels. Immunochemical analysis revealed that increased expression of ETV1 was correlated with KIT in the 156 patients. In addition, the frequency of ETV1 positivity was higher when compared with KIT [50.0% (9/18) vs 38.9% (7/18)] particularly in high-risk GISTs. Analysis of western blotting data showed that total protein isoforms of Raf, MEK and ERK were similar in the GIST tissues as well as in the uninvolved normal tissues. In contrast, the level of phospho-Raf, phospho-MEK and phospho­ERK were decreased in the tumor group. Moreover, enhanced signaling molecules such as Bcl-2 and Dvl2/GSK-3ß/ß-catenin/Smad2 were detected, showing a significant difference in comparison with the uninvolved normal cases. We conclude that ETV1, a member of the ETS family, is upregulated in GISTs, and its signaling is integrated into a cellular signaling network for resistance to apoptosis, tumor cell invasion and survival.