Evaluation of vital genes correlated with CD8 + T cell infiltration as prognostic biomarkers in stomach adenocarcinoma.

BACKGROUND: Infiltration of CD8 + T cells in the tumor microenvironment is correlated with better prognosis in various malignancies. Our study aimed to investigate vital genes correlated with CD8 + T cell infiltration in stomach adenocarcinoma (STAD) and develop a new prognostic model. METHODS: Using the STAD dataset, differentially expressed genes (DEGs) were analyzed, and co-expression networks were constructed. Combined with the CIBERSORT algorithm, the most relevant module of WGCNA with CD8 + T cell infiltration was selected for subsequent analysis. The vital genes were screened out by univariate regression analysis to establish the risk score model. The expression of the viral genes was verified by lasso regression analysis and in vitro experiments. RESULTS: Four CD8 + T cell infiltration-related genes (CIDEC, EPS8L3, MUC13, and PLEKHS1) were correlated with the prognosis of STAD. Based on these genes, a risk score model was established. We found that the risk score could well predict the prognosis of STAD, and the risk score was positively correlated with CD8 + T cell infiltration. The validation results of the gene expression were consistent with TCGA. Furthermore, the risk score was significantly higher in tumor tissues. The high-risk group had poorer overall survival (OS) in each subgroup. CONCLUSIONS: Our study constructed a new risk score model for STAD prognosis, which may provide a new perspective to explore the tumor immune microenvironment mechanism in STAD.

Transcriptome sequencing and miRNA-mRNA network construction in exosome of macrophage M2 in stomach adenocarcinoma.

BACKGROUND: Stomach adenocarcinoma (STAD) is the most common histological type of gastric cancer (GC). Macrophages are an essential part of the tumor microenvironment. We attempted to search for potential molecular markers associated with macrophages, which might be helpful for STAD diagnosis and treatment. METHODS: Firstly, exosome in macrophages was extracted for RNA sequencing to identify differentially expressed microRNAs (miRNAs) (DEmiRNAs). Then, DEmiRNAs and differentially expressed mRNAs (DEmRNAs) were screened in the Cancer Genome Atlas (TCGA) database. The miRNAs related to macrophage M2 polarization were obtained by intersecting the DEmiRNAs obtained from the sequencing data and TCGA data. Using the Pearson correlation coefficient method, the mRNAs significantly related to macrophage M2 were screened out, followed by construction of the macrophage M2-miRNA-mRNA network. Subsequently, real-time-polymerase chain reaction (RT-PCR) and online datasets were applied to validate the expression of DEmiRNAs and DEmRNAs. RESULTS: A total of 6 DEmiRNAs were identified in RNA sequencing; 59 DEmiRNAs and 1838 DEmRNAs were identified in TCGA database. Among which, a common miRNA (hsa-miR-133a-3p) associated with the M2 polarization of macrophages was identified. Fifteen common mRNAs were obtained between DEmRNAs and mRNAs targeted by DEmiRNAs. Eventually, a core macrophage M2-1 down-regulated miRNA-7 and up-regulated mRNAs network was constructed, including hsa-miR-133a-3p, SLC39A1, TTYH3, HAVCR2, TPM3, XPO1, POU2F1, and MMP14. The expression of miRNA and mRNAs was in line with the validation results of RT-PCR and online datasets. CONCLUSION: In this study, the screening of biomarkers in exosome of macrophage M2 may contribute to the prognosis of STAD patients.

Identification of 8-gene risk prediction signature associated with NOTCH1 in stomach adenocarcinoma based on bioinformatics analysis.

Background: Stomach adenocarcinoma (STAD), is the most common histological type of gastric cancer (GC) with high mortality and poor prognosis. We sought to investigate the contribution of Notch receptor 1 (NOTCH1) to STAD immunity. Methods: The profiles of immune cells in STAD cohorts were compared, and a correlation analysis between the NOTCH1 gene and tumor immune cell infiltration was then conducted. The immune-related genes (IRGs) associated with the NOTCH1 gene were identified. Based on the NOTCH1-associated IRGs, multiple-gene risk prediction signatures were established. The relationship between the expression levels of the selected IRGs and overall survival (OS) was analyzed by a univariate analysis. The risk score was calculated using the formula of ß1x1 + ß2x2 +... + ßixi. A prognostic nomogram was constructed to predict individuals' survival probabilities. Results: In STAD, NOTCH1 expression levels were significantly negatively associated with tumor-infiltrating lymphocyte (TIL) Act dendritic cells (DCs) (r=-0.196, P value =6.24e-05), TIL cluster of differentiation (CD) 56 bright cells (r=-0.115, P value =0.0193), TIL immature DCs (r=-0.293, P value =1.16e-09), TIL monocyte cells (r=-0.185, P value =0.000149), TIL central memory T CD4 cells (r=-0.126, P value =0.0103), and TIL gamma delta T cells (r=-0.149, P value =0.00229). The resulting risk scores of the 8-gene risk prediction signature (corticotrophin releasing hormone receptor 2 (CRHR2) (HR =1.858, P value =0.048), fms related receptor tyrosine kinase 1 (FLT1) (HR =1.268, P value =0.048), fms related receptor tyrosine kinase 4 (FLT4) (HR =1.334, P value =0.031), glial fibrillary acidic protein (GFAP) (HR =2.739, P value =0.008), platelet-derived growth factor receptor beta (PDGFRB) (HR =1.192, P value =0.02), prostaglandin D2 receptor (PTGDR) (HR =1.564, P value =0.049), semaphorin 5B (SEMA5B) (HR =1.154, P value =0.029), and tyrosine kinase 2 (TYK2) (HR =0.734, P value =0.041) were independent prognostic predictors for STAD patients. Conclusions: NOTCH1 could be a potential target for STAD. The mechanisms underpinning NOTCH1-medicated prognostic values of immune signatures should be further explored.

Inorganic Pillar Center-Facilitated Counterdiffusion Synthesis for Highly H2 Perm-Selective KAUST-7 Membranes.

Fluorinated metal-organic framework materials (NbOFFIVE-1-Ni, also referred to as KAUST-7) have attracted widespread attention because of their high chemical stability and thermal stability, outstanding tolerance with water and H2S, and high CO2-adsorption selectivity over H2 and CH4. KAUST-7 was expected to be a new membrane material candidate for H2/CO2 separation because of the hindered permeation of CO2 resulting from the interaction between CO2 and (NbOF5)2- of the KAUST-7 framework. A highly H2 perm-selective KAUST-7 membrane was first achieved using a novel strategy of inorganic pillar center-facilitated counterdiffusion (IPCFCD) proposed by us. The IPCFCD method not only effectively avoided the corrosion of hydrofluoric acid to α-Al2O3 tubes in the process of preparing KAUST-7 membranes, but also better reduced grain boundary defects because of the faster nucleation rate and resultant high crystallinity. The KAUST-7 membrane exhibited a high H2/CO2 separation factor (SF) of 27.30 for the 1:1 H2/CO2 binary gas mixture with a high H2 permeance of 5.30 × 10-7 mol m-2 s-1 Pa-1 under ambient conditions and a slight decrease of the H2/CO2 SF with increasing operation temperature and presence of steam. This study highlighted the importance of pre-synthesizing inorganic pillar centers (NiNbOF5 intermediate) and the innovation of a membrane formation process for synthesizing polycrystalline KAUST-7 membranes. Most important of all, our study provided a novel approach to overcome the challenge in fabricating metal-organic framework membranes containing corrosive reactants for the corresponding supports.

Integrated analysis and knockdown of RAB23 indicate the role of RAB23 in gastric adenocarcinoma.

BACKGROUND: The present study aimed to identify key differentially expressed genes (DEGs) and miRNAs (DEmiRNAs) in gastric adenocarcinoma. METHODS: We performed integrated analysis to determine DEGs and DEmiRNAs of gastric adenocarcinoma based on the GEO database. A DEmiRNA-target interaction network was established. GO and KEGG pathway enrichment analyses were utilized. Then, MKN45 cells were transfected with shRNA-RAB23 to knock down the expression of RAB23. CCK-8, transwell and flow cytometry assays were utilized to measure the capacities for cell proliferation, migration and apoptosis, and the apoptosis-related gene and protein levels were measured by using polymerase chain reaction (PCR) and Western blot, respectively. Colocalization analysis of Snc1 with the vesicular protein VAMP3 and the endoplasmic reticulum protein Calnexin was performed to assess the influence of RAB23 on vesicle transport. Finally, we performed metabolomic analysis by using gas chromatography mass spectrometry (GC-MS). RESULTS: We performed MMIA of gastric adenocarcinoma based on two miRNA datasets and two mRNA datasets. A total of 4,586 DEmRNAs and 30 DEmiRNAs were obtained. The DEmRNAs of gastric adenocarcinoma were significantly enriched in PI3K/Akt signaling. We identified three interactions, hsa-miR-23a-3p-PTPN4, hsa-miR-20b-5p (hsa-miR-130a-3p)-TNFRSF10B, and hsa-miR-130a-3p (hsa-miR-363-3p)-RAB23, that may be related to the pathogenesis of gastric adenocarcinoma. The growth of MKN45 cells was inhibited by RAB23 knockdown via shRNA-RAB23 transfection. Metabolic analysis of three groups revealed a number of significantly altered metabolites, including glycerol, niacinamide, and nonadecanoic acid methylester. CONCLUSIONS: RAB23 might be a target gene of hsa-miR-130a-3p and hsa-miR-363-3p. In gastric adenocarcinoma cells, knockdown of RAB23 inhibited cell proliferation, migration, and invasion and increased apoptosis by downregulating the PI3K/Akt pathway.

Dual inhibitor of PI3K and mTOR (NVP-BEZ235) augments the efficacy of fluorouracil on gastric cancer chemotherapy.

PURPOSE: NVP-BEZ235 is a recently developed dual inhibitor of PI3K and mTOR and shows good inhibitory effects on several types of tumors. However, the efficacy of NVP-BEZ235 on gastric cancer therapy remains unclear. This study aimed to investigate the potential of NVP-BEZ235 as a new agent to enhance chemotherapy for gastric cancer. METHODS: Human gastric cancer MKN-45 cells or nude mice xenografted with MKN-45 cells were treated by NVP-BEZ235 and fluorouracil (5-FU) alone or in combination. The proliferation, invasion, apoptosis, and chemoresistance of gastric cancer cells were examined in vivo and in vitro. RESULTS: In vitro, combined treatment with NVP-BEZ235 and 5-FU showed synergistic inhibitory effects on proliferation, migration, and invasion and synergistic stimulating effects on apoptosis of MKN-45 cells. In vivo, NVP-BEZ235 and 5-FU synergistically inhibited the growth and induced apoptosis of MKN-45 xenografts. Mechanistically, NVP-BEZ235 inhibited PI3K/Akt/mTOR signaling; decreased the levels of Bcl-2, MMP9, and VEGF; but increased the levels of Bax and cleaved caspase-3 in MKN-45 xenografts. CONCLUSION: NVP-BEZ235 enhances the antitumor efficacy of 5-FU. Therefore, NVP-BEZ235 is a promising agent to enhance chemotherapy for gastric cancer.

Sensitization of Gastric Cancer Cells to 5-FU by MicroRNA-204 Through Targeting the TGFBR2-Mediated Epithelial to Mesenchymal Transition.

BACKGROUND/AIMS: Gastric cancer (GC) is the most common gastrointestinal malignancy, causing cancer-related deaths in East Asia. MicroRNAs (miRNAs) are small non-coding RNAs aberrantly expressed in human tumors. In this study, we aim to investigate the roles of miR-204 in the epithelial to mesenchymal transition (EMT)-associated chemosensitivity. METHODS: The expression of miR-204 was detected in clinical tumor samples and GC cell lines by real time PCR. Tumor cell's growth, invasion, and migration were measured by MTT assay, wound healing assay, and transwell invasion assay, respectively. Western blot method was used to detect the protein levels of indicated genes. Luciferase reporter assay was performed to validate the target gene of miR-204. The in vivo role of miR-204 was measured using a xenograft mouse model of GC. RESULTS: By comparing the expressions of miR-204 in human gastric tumors and their adjacent normal tissues, it was disclosed that miR-204 was significantly downregulated in gastric tumors. Moreover, miR-204 was downregulated in multiple GC cell lines compared with normal gastric epithelial cells. Overexpression of miR-204 suppressed GC cells' proliferation, invasion, and migration. It is noteworthy that 5-FU treatments induced miR-204 expression and suppressed TGF-ß pathway. By establishment of 5-FU resistant GC cell line, it was revealed that miR-204 was significantly downregulated in 5-FU resistant GC cells, representing mesenchymal features with downregulation of epithelial marker, while mesenchymal markers were upregulated. We identified TGFBR2 as a direct target of miR-204 by Western blot method and luciferase assay in GC cells and tumor samples as well. In addition, overexpression of miR-204 sensitized GC cells to 5-FU in vitro. Xenograft experiments demonstrated that the combination of miR-204 and 5-FU efficiently inhibited tumor growth and improved survival rate of mice as well. Eventually, we illustrated the restoration of TGFBR2 in miR-204 overexpression GC cells, which recovered resistance to 5-FU treatments compared with miR-204 overexpression GC cells. CONCLUSION: This study describes a miRNA-based therapeutic strategy against 5-FU resistance in GC, contributing to the development of anti-chemoresistance therapeutic agents.

Effect of Splenectomy Combined with Resection for Gastric Carcinoma on Patient Prognosis.

BACKGROUND For patients with stage IV gastric cancer, it is unclear whether splenectomy combined with palliative surgery is needed to reduce tumor load and relieve symptoms. The objective of the present study was to investigate the effect of splenectomy combined with palliative resection for stage IV gastric carcinoma on immunological dysfunction and patient prognosis. MATERIAL AND METHODS We retrospectively analyzed medical records of 106 stage IV gastric cancer patients who underwent palliative surgery; of these, 49 patients were treated with palliative resection for gastric carcinoma combined with splenectomy, while the other 57 patients retained their spleens. The immunologic function and prognosis in these 2 groups were examined and compared. RESULTS The immune function of patients in the group that retained their spleens was better later in the postoperative course than in the resection group. The groups did not show statistically significant differences in postoperative infectious complications, median survival time, and survival rate; however, the average postoperative hospitalization time of patients in the retained group was significantly shorter. CONCLUSIONS Splenectomy combined with gastric cancer resection did not improve the prognosis of the patients; patients who retained their spleens had faster recovery and improved immune function. However, whether retaining the spleen is an independent factor improving the prognosis needs further investigation.

MicroRNA-181b inhibits glycolysis in gastric cancer cells via targeting hexokinase 2 gene.

Cancer cells usually utilize glucose as a carbon source for aerobic glycolysis, which is named as ``Warburg effect''. Recent studies have shown that MicroRNAs (miRNAs), a class of short and non-coding RNAs, play a role in the regulation of metabolic reprograming in cancer cells. In the present study, we report that miR-181b negatively regulates glycolysis in gastric cancer cells. Over-expression of miR-181b mimics reduces the glucose uptake and lactate production, while increasing the cellular ATP levels in NCI-N87 and MGC80-3 cells. At the molecular level, miR-181b directly inhibits the expression level of hexokinase 2 (HK2), a key enzyme that catalyzes the first step of glycolysis, through targeting its 3'-untranslated region. In addition, miR-181b represses cell proliferation and migration and is dramatically down-regulated in human gastric cancers. Therefore, our data disclose a novel function of miR-181b in reprogramming the metabolic process in gastric cancer.

F-box protein FBXL2 inhibits gastric cancer proliferation by ubiquitin-mediated degradation of forkhead box M1.

F-box/LRR-repeat protein 2 (FBXL2), a component of Skp-Cullin-F box (SCF) ubiquitin E3 ligase, has been shown to inhibit tumorigenesis by targeting and ubiquitinating several oncoproteins. However, its role in gastric cancer remains poorly understood. Here, by tandem mass spectrometry, we show that FBXL2 interacts with forkhead box M1 (FoxM1) transcription factor. As a result, FBXL2 promotes ubiquitination and degradation of FoxM1 in gastric cancer cells. Furthermore, overexpression of FBXL2 inhibits, while its deficiency promotes cell proliferation and invasion. Expression levels of cell-cycle regulators (Cdc25B and p27), which are down-stream target effectors of FoxM1, are also regulated by FBXL2. Therefore, our results uncover a previous unknown network involving FBXL2 and FoxM1 in the regulation of gastric cancer growth.

Inhibition of autophagy by bafilomycin A1 promotes chemosensitivity of gastric cancer cells.

Autophagy is an intracellular degradation pathway that delivers organelles or protein to the lysosome and has been recently implicated in the resistance of gastric cancer to chemotherapy. This study aimed to investigate whether blocking autophagy is a new approach for the treatment of chemoresistant gastric cancer. SGC-7901 gastric cancer cell line was treated with 5-fluorouracil (5-FU) or/and autophagy inhibitor bafilomycin A1. Cell viability and growth were evaluated by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) and clonogenic assay. Apoptosis was evaluated by flow cytometry. Cell migratory and invasive ability were evaluated by migration and invasion assays. Autophagy was evaluated by scanning electron microscopic, acridine orange staining, and Western blot analysis. We observed that 5-FU induced autophagy in SGC-7901 cells. Bafilomycin A1 decreased the viability and clone formation, inhibited the invasive and migratory ability, and increased the apoptosis of SGC-7901 cells. Taken together, our data suggest that chemotherapy-induced autophagy contributes to gastric cancer chemoresistance, and the inhibition of autophagy is a promising strategy for gastric cancer therapy.

[Effect of bafilomycin A1 on proliferation and oxaliplatin sensitivity in gastric cancer MGC-803 cells].

OBJECTIVE: To investigate the effect of bafilomycin A1 (BAF) on the cell proliferation, invasiveness, apoptosis, and oxaliplatin sensitivity in gastric cancer MGC-803 cells. METHODS: MGC-803 cells were divided into control group, BAF group, oxaliplatin group, and BAFµ oxaliplatin group. MTT assay and plate clone formation assay were used to assess the viability and colony forming ability of the cells after the treatments. The expression of nucleosomes in the cells was examined with ELISA. The cell migration and invasion after the treatments were evaluated. Western blotting was performed to detect the expression of Bcl-2 and Bax in the treated cells, and scanning electron microscopy, immunohistochemistry and Western blotting were employed to to observe the cell autophagy. RESULTS: Compared with the control cells, the cells treated with BAF showed a substantial decrease in autophagosome accumulation with attenuated cell proliferation, migration and invasion. Compared with cells treated with oxaliplatin alone, the cells treated with both BAF and oxaliplatin showed significantly lowered autophagosome accumulation, suppressed cell proliferation, migration and invasion, increased cell apoptosis, increased Bax expression and lowered Bcl-2 expression. CONCLUSION: BAF can inhibit the proliferation and invasiveness of MGC-803 cells, promote cell apoptosis by inhibiting autophagy, and enhances the sensitivity of the cells to oxaliplatin.

[Application of a lipid emulsion for parenteral nutrition support in intensive care patients following gastrointestinal surgeries].

OBJECTIVE: To investigate the effect of parenteral nutrition support with a lipid emulsion formulation (containing soybean oil, medium chain triglycerides, olive oil, and fish oil [SMOF]) in intensive care patients following major gastrointestinal surgeries. METHODS: According to a randomized, prospective and case-controlled design, 72 intensive care patients following major gastrointestinal surgeries between January and December, 2014 were randomized equally into SMOF group and control group to receive parenteral nutrition support with SMOF and medium or long chain lipid emulsion, respectively. Before and at 4 and 9 days after commencement of parenteral nutrition support, the patients were examined for alanine aminotransferase (ALT), total bilirubin (TBIL), albumin (propagated), C-reactive protein (CRP), interleukin 6 (IL-6), and endotoxin levels. The patients' average length of stay in intensive care unit (ICU), the days of using antibiotics, and the incidence rate of postoperative complication were recorded. RESULTS: On day 4 postoperatively, the levels of CRP and IL-6 were significantly lower in SMOF group than in the control group (t=2.669 and 2.676, respectively; P<0.05), and on day 9, the patients in SMOF group showed significantly lower levels of ALT, TBIL, CRP and IL-6 (t=2.487, 3.497, 3.762, 2.180, respectively; P<0.05) than the control group, but ALB and endotoxin levels remained comparable between the two groups. The average length of stay in ICU and the days of using antibiotics were significantly shorter in SMOF group than in the control group (t=2.94 and 2.17, respectively; P<0.05); SMOF group showed a lower incidence of postoperative infections than the control group, but the difference was not statistically significant (χ² =1.047, P>0.05). CONCLUSION: For intensive care patients following major gastrointestinal surgeries, postoperative parenteral nutrition support with SMOF can effectively reduce the release of inflammatory mediators, protect important visceral functions, reduce postoperative complications, shorten the length of ICU stay, and improve the prognosis of the patients.

Geldanamycin induces apoptosis in human gastric carcinomas by affecting multiple oncogenic kinases that have synergic effects with TNF-related apoptosis-inducing ligand.

The aim of the present study was to evaluate the effect of geldanamycin (GA) on the treatment of human gastric carcinomas and to investigate the molecular mechanism that provides the basis for the combination of GA with the tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) induction strategy. The expression of target proteins at the mRNA level was determined using reverse transcription-polymerase chain reaction (RT-PCR), and apoptosis was evaluated with the terminal deoxynucleotidyl transferase mediated digoxigenin-dUTP nick-end labeling and Annexin V/propidium iodide (PI) staining methods. Phosphorylation of targeted kinases was studied using immunocytochemistry methods, and malignant phenotypes were studied using in vitro assays. GA treatment inhibits proliferation, migration and invasion, and induces apoptosis in human gastric cancer SGC-7901 cells, most likely by decreasing the expression of B-RAF and by phosphorylation of protein kinase B (AKT) and ERK. The inhibitory role of AKT in TRAIL regulation holds considerable potential for achieving a synergic effect in clinical therapy, using a combination of GA treatment and TRAIL induction. The present study provides a basis for the future application of heat shock protein 90 (Hsp90) inhibitors, such as GA, in the clinical treatment of gastric cancer, particularly in combination therapies with TRAIL inducers.

Tuning aluminum spatial distribution in ZSM-5 membranes: a new strategy to fabricate high performance and stable zeolite membranes for dehydration of acetic acid.

A novel ZSM-5 membrane with a low Si/Al ratio and homogeneous aluminum spatial distribution was achieved from an organic template-free inorganic gel in the presence of both OH(-) and F(-) ions and the obtained ZSM-5 membrane exhibited excellent selectivity and high flux and stability for dehydration of acetic acid in a wide AcOH content range.

[Risk factors associated with postoperative complications after reoperation for recurrent Crohn disease].

OBJECTIVE: To evaluate the risk factors of postoperative complications after reoperation for recurrent Crohn disease(CD). METHODS: From 1995 to 2009, 65 patients undergoing reoperation for recurrent CD were identified in the First Affiliated Hospital of Fujian Medical University. Risk factors of postoperative complications were analyzed. These patients were matched by age to 65 patients undergoing primary operation and treatment outcomes were compared between primary operation and reoperation. RESULTS: Postoperative complications were observed in 25 cases(38.5%) undergoing reoperation for CD recurrence and the rate of postoperative complication was higher than that after primary operation(12.3%). Postoperative complications rate in patients with stoma was significantly lower than those without stoma(15.8% vs. 47.8%, χ(2)=5.831, P=0.016). Compared to primary operation, reoperation had longer operative time, more severe intraperitoneal adhesion, and a longer postoperative hospital stay(all P<0.05). CONCLUSION: Reoperation for CD recurrence is associated with higher postoperative complications. Temporary stoma may decrease the rate of postoperative complication.