Normal Gastric Mucosa Tissues Research Articles

Methionine restriction promotes cisplatin sensitivity of gastric cancer resistant cells by down-regulating circ-CDK13 level

BackgroundMethionine restriction (MR) is a research direction in the treatment of gastric cancer (GC). The aim of this study was to investigate the molecular mechanism of MR on enhancing cisplatin (DDP) sensitivity of drug-resistant GC cells. MethodsTwenty pairs of GC tissues and adjacent normal gastric mucosa tissues were collected. DDP-resistant cell lines (KATO/DDP and MKN45/DDP), mouse model of GC and GC patient-derived organoid (PDO) models were established. Lentivirus-mediated METase overexpression was used for MR. Cell viability and apoptosis were detected by MTT assay and flow cytometry. Western blotting was used to detect multi-drug resistance-1 (MDR1), MDR-associated protein 1 (MRP1) eukaryotic initiation factor 4A-Ⅲ (EIF4A3), and METase protein expressions. The levels of circRNAs were detected by qRT-PCR. Tumor volume and weight were measured. The proliferation of tumor cells was detected by immunohistochemical staining. ResultsThe differentially expressed circRNAs of GC were screened in Gene Expression Omnibus database. MR in KATO/DDP and MKN45/DDP cells significantly down-regulated circ-CDK13 level. Overexpression of circ-CDK13 significantly inhibited apoptosis of sensitive cells (KATO III and MKN45). Interference with circ-CDK13 significantly promoted apoptosis of drug-resistant cells (KATO/DDP and MKN45/DDP). MR enhanced the DDP sensitivity of GC resistant cells, GC PDO and GC mice by down-regulating circ-CDK13. EIF4A3 binds to the downstream flanking sequence of circ-CDK13, and interference with EIF4A3 reduces circ-CDK13 levels, but does not affect CDK13. The expressions of circ-CDK13 and EIF4A3 in GC clinical samples were increased and positively correlated. Simultaneously overexpression of METase and EIF4A3 in resistant cells inhibited apoptosis, and further interference with circ-CDK13 reversed this effect. ConclusionMR inhibits circ-CDK13 level by down-regulating EIF4A3, thereby increasing the sensitivity of GC drug-resistant cells to DDP.

Clinical Analysis of Multidrug Resistance-Related Protein Expression in Gastric Cancer Cells

Objective: This study aims to clinically analyze the expression of multidrug resistance-related proteins in gastric cancer cells. Methods: In this study, archival paraffin blocks from 50 surgical specimens of gastric cancer collected in our hospital between 2021 and 2022 were included. Each specimen included tumor lesion tissue and normal gastric mucosa tissue located more than 5 cm away from the cancer. Immunohistochemistry was performed to detect P-glycoprotein (P-gp), glutathione S-transferase pi (GST-π), and B-cell lymphoma-extra-large (Bcl-xL) expression, and the relevant data were collected and analyzed. Results: The positive expression rates and high expression levels of P-gp, GST-π, and Bcl-xL in gastric cancer tissues were significantly higher than in normal gastric mucosa tissues (p < 0.05). The expression of multidrug resistance proteins (P-gp, GST-π, Bcl-xL) in gastric cancer was not associated with patient clinical characteristics (tumor clinical stage, depth of invasion, and lymph node metastasis) (p > 0.05); Bcl-xL expression level was positively correlated with tumor differentiation degree (p < 0.05). Conclusion: The results of this study reveal the expression patterns of multidrug resistance-related proteins in gastric cancer tissues and shed light on the relationship between the expression of these proteins and multidrug resistance in gastric cancer.

Dark horse target Claudin18.2 opens new battlefield for pancreatic cancer.

Pancreatic cancer is one of the deadliest malignant tumors, which is a serious threat to human health and life, and it is expected that pancreatic cancer may be the second leading cause of cancer death in developed countries by 2030. Claudin18.2 is a tight junction protein expressed in normal gastric mucosal tissues, which is involved in the formation of tight junctions between cells and affects the permeability of paracellular cells. Claudin18.2 is highly expressed in pancreatic cancer and is associated with the initiation, progression, metastasis and prognosis of cancer, so it is considered a potential therapeutic target. Up to now, a number of clinical trials for Claudin18.2 are underway, including solid tumors such as pancreatic cancers and gastric cancers, and the results of these trials have not yet been officially announced. This manuscript briefly describes the Claudia protein, the dual roles of Cluadin18 in cancers, and summarizes the ongoing clinical trials targeting Claudin18.2 with a view to integrating the research progress of Claudin18.2 targeted therapy. In addition, this manuscript introduces the clinical research progress of Claudin18.2 positive pancreatic cancer, including monoclonal antibodies, bispecific antibodies, antibody-drug conjugates, CAR-T cell therapy, and hope to provide feasible ideas for the clinical treatment of Claudin18.2 positive pancreatic cancer.

LINC00665 activating Wnt3a/β-catenin signaling by bond with YBX1 promotes gastric cancer proliferation and metastasis.

Long noncoding RNAs (lncRNAs) play a key role in human cancer development; nevertheless, the effect of lncRNA LINC00665 on the progression of gastric cancer (GC) still unclear. In this study, we found that LINC00665 expression is upregulated in GC than normal gastric mucosa tissues and higher LINC00665 expression is associated with a poor prognosis in GC patients. Downregulated LINC00665 inhibited GC cells proliferation, invasion, and migration in vitro. Pulmonary metastasis animal models showed that downregulated LINC00665 could reduce the lung metastasis of GC in vivo. Tumor organoids were generated from human malignant GC tissues, downregulated LINC00665 could inhibit the growth of the organoids of GC tissues. Mechanistically, downregulated LINC00665 could inhibit GC cells EMT. RNA pulldown, RIP, and RIP-seq studies found that LINC00665 can bind to the transcription factor YBX1 and form a positive feed-forward loop. The luciferase reporter and CHIP results showed that YBX1 could regulate the transcriptional activity of Wnt3a, and downregulation of LINC00665 could block the activation of Wnt/β-catenin signaling. In conclusion, our results identified a feedback loop between LINC00665 and YBX1 that activates Wnt/β-catenin signaling, and it may be a potential therapeutic approach to suppress GC progression.

FJX1 overexpression is associated with poor prognosis and promotes gastric cancer proliferation via the PI3K/AKT signaling pathway

To investigate the expression of four-jointed box kinase 1 (FJX1) in gastric cancer (GC), its correlation with survival outcomes of the patients, and its role in GC progression. The expression level of FJX1 in GC tissues and normal gastric mucosal tissues and its correlation with the survival outcomes of GC patients were analyzed using TCGA and GEO database GC cohort. Immunohistochemistry was used to detect FJX1 expression level in clinical specimens of GC tissue, and its correlations with the patients' clinicopathological parameters and prognosis were analyzed. Bioinformatic analysis was performed to identify the potential pathways of FJX1 in GC. The effects of FJX1 overexpression or FJX1 silencing on GC cell proliferation and expressions of proliferation-related proteins, PI3K, AKT, p-PI3K, and p-AKT were evaluated using CCK-8 assay and Western blotting. The effect of FJX1 overexpression on GC cell tumorigenicity was evaluated in nude mice. GC tissues showed significantly higher expressions of FJX1 mRNA and protein compared with normal gastric mucosa tissues (P < 0.05). The high expression of FJX1 was associated with poor prognosis of GC patients (P < 0.05) and served as an independent risk factor for poor survival outcomes in GC (P < 0.05). FJX1 was expressed mainly in the cytoplasm of GC cells in positive correlation with Ki67 expression (R=0.34, P < 0.05), and was correlated with CA199 levels, depth of tumor infiltration and lymph node metastasis of GC (P < 0.05). In the cell experiment, FJX1 level was shown to regulate the expressions of Ki67 and PCNA and GC cell proliferation (P < 0.05). Gene set enrichment analysis indicated that the PI3K/AKT pathway potentially mediated the effect of FJX1, which regulated the expressions of PI3K and AKT and their phosphorylated proteins. In nude mice, FJX1 overexpression in GC cells significantly promoted the growth of the transplanted tumors (P < 0.05). FJX1 is highly expressed in GC tissues and is correlated with poor prognosis of GC patients. FJX1 overexpression promotes GC cell proliferation through the PI3K/AKT signaling pathway, and may serve as a potential prognostic biomarker and therapeutic target for GC.

Function of hsa_circ_0006646 as a competing endogenous RNA to promote progression in gastric cancer by regulating the miR-665-HMGB1 axis.

Mounting evidences indicate that circular RNAs (circRNAs) are a novel class of non-coding RNAs and play vital roles in the tumorigenesis and aggressiveness including gastric cancer (GC). Nevertheless, the precise functions and underlying mechanisms of circRNAs in GC remain largely unknown. The Gene Expression Omnibus (GEO) data set GSE163416 was analyzed to screen the key circRNAs in GC. hsa_circ_0006646 was chosen for further study. GC tissues and matched adjacent normal gastric mucosal epithelial tissues were obtained from the Fourth Hospital of Hebei Medical University. The expressions of hsa_circ_0006646 was detected using quantitative real-time polymerase chain reaction (qRT-PCR). hsa_circ_0006646 was knocked down to identify its effects on GC cells. Bioinformatics algorithms were analyzed to predict the microRNA (miRNAs) potentially sponged by hsa_circ_0006646 and its target genes. Fluorescence in situ hybridization (FISH) was conducted to determine the subcellular location of hsa_circ_0006646 and the predicted miRNA. Then, qRT-PCR, luciferase reporter assay, radioimmunoprecipitation assay, Western blotting, and miRNA rescue experiments were used to confirm the hsa_circ_0006646-related regulatory axis in GC. Cell Counting Kit-8 (CCK-8), colony formation, wound healing, and Transwell experiments were performed to determine the effect of the hsa_circ_0006646-related regulatory axis on GC cells' malignant behaviors in vitro. The xenograft tumor mouse model was established to evaluate the effect of hsa_circ_0006646 in vivo. hsa_circ_0006646 exhibited a high expression in GC tissues as compared to corresponding adjacent normal gastric mucosal epithelial tissues and its high expression was positively correlated with TNM stage, lymph node invasion and poor prognosis (P<0.05). Knockdown of hsa_circ_0006646 suppressed the proliferation, colony formation, migration, and invasion in GC cells (all P<0.05). hsa_circ_0006646 upregulated high mobility group box 1 (HMGB1) by sponging miR-665 in GC cells (P<0.05). The hsa_circ_0006646-miR-665-HMGB1 axis promoted malignant behaviors and epithelial-mesenchymal transition (EMT) in GC cells by activating the Wnt/β-catenin pathway (P<0.05). The existence of hsa_circ_0006646-miR-665-HMGB1 axis was confirmed in GC specimens (P<0.05). Consequently, down-regulated hsa_circ_0006646 inhibited the progression and EMT of GC cells in vivo (P<0.05). For the first time, we demonstrated that hsa_circ_0006646-miR-665-HMGB1 axis exerted its tumor-promoting effects in GC, which suggested that hsa_circ_0006646 could be potentially targeted for GC treatment.

CircSCUBE3 Reduces the Anti-gastric Cancer Activity of Anti-PD-L1.

The progression of gastric cancer (GC) is closely related to tumor immune escape. The research, therefore, studied the impact of possible circRNAs on the immune escape of GC tumors and the underlying mechanisms. Here, to explore circRNAs that may affect GC, the differential circRNAs in six normal gastric mucosal tissues and six GC samples (GSM2005868-GSM2005879) were analyzed through the bioinformatics website circmine, and hsa_circ_0076092 (circSCUBE3) was identified as the research object. In vitro assays revealed the functions of circSCUBE3 and its downstream miRNA/mRNA axis in GC cells. The effect of circSCUBE3 against PD-1 anti-tumor activity was evaluated in vivo. The relationship between circSCUBE3 and miR-744-5p, miR-744-5p, and SLC7A5 was identified by RNA immunoprecipitation and dual-luciferase reporter experiments. The effect of SLC7A5 on GC immune escape by regulating PD-L1 expression was assessed by co-culture system and flow cytometry. CircSCUBE3 was up-regulated in human GC tissues and GC cell lines. circSCUBE3 was associated with poor prognosis in GC patients. Functional experiments reported that circSCUBE3 knockdown could suppress GC immune escape. Mechanistically, circSCUBE3 bound to miR-744-5p, which further targeted SLC7A5, and SLC7A5 can affect GC immune escape by regulating PD-L1. Furthermore, in vivo assay manifested that circSCUBE3 attenuated the anti-tumor effect of PD-L1. Our study revealed the importance of the circSCUBE3/miR-744-5p/SLC7A5 axis in GC immune escape and anti-PD-1 resistance.

Circular RNA 0001789 sponges miR-140-3p and regulates PAK2 to promote the progression of gastric cancer

BackgroundGastric cancer (GC) is the third-leading cause of cancer-associated mortalities globally. The deregulation of circular RNAs (circRNAs) and microRNAs (miRNAs or miRs) is widely implicated in the pathogenesis and progression of different cancer types.MethodsThe expression profiling of circRNAs in GC is required to identify crucial circRNAs as biomarkers or therapeutic targets. In the present study, a published circRNA microarray dataset was used to identify differentially expressed circRNAs between GC tissues and normal gastric mucosa tissues. Reverse transcription-quantitative PCR was performed to validate the expression of circ_0001789. Fisher’s exact test, receiver operating characteristic curve and Kaplan-Meier plots were employed to analyze the clinical significance of circ_0001789. The miRNA targets of circ_0001789 were predicted using an online database, and their functional interaction was further confirmed by RNA pull-down, RNA immunoprecipitation and dual luciferase reporter assays. Transwell assays were conducted to investigate the biological functions of circ_0001789, miR-140-3p and p21 activated kinase 2 (PAK2) in the migration and invasion of GC cells. A xenograft mouse model was established to validate the role of circ_0001789 in the tumorigenesis of GC cells.Resultscirc_0001789 was identified as a highly expressed circRNA in GC tissues versus normal gastric mucosa tissues. Silencing circ_0001789 attenuated the malignancy of GC cells, and exosomal circ_0001789 was sufficient to regulate the malignant phenotype of GC cells. miR-140-3p was further identified as a downstream target of circ_0001789, which showed a negative correlation with circ_0001789 expression in GC tissues. Overexpression of miR-140-3p suppressed cell migration, invasion and epithelial-mesenchymal transition in GC cells. PAK2 was identified as the target of miR-140-3 to mediate the malignant phenotype of GC cells.ConclusionThe present data suggested that the upregulation of circ_0001789 was associated with the progression of GC and with poor prognosis in patients with GC, and that miR-140-3p/PAK2 served as the downstream axis to mediate the oncogenic effect of circ_0001789.

Identification and validation of crucial lnc-TRIM28-14 and hub genes promoting gastric cancer peritoneal metastasis

BackgroundGastric cancer peritoneal metastasis (GCPM) is an important cause of cancer-related deaths worldwide. Long non-coding RNAs (lncRNAs) play a key role in the regulation of GCPM, but the underlying mechanisms have not been elucidated.MethodsHigh-throughput RNA sequencing (RNA-seq) was performed on four groups of clinical specimens (non-metastatic gastric cancer primary tumor, adjacent normal gastric mucosal tissue, gastric cancer primary tumor with peritoneal metastasis and adjacent normal gastric mucosal tissue). After sequencing, many lncRNAs and mRNAs were screened for further Weighted Gene Co-expression Network Analysis (WGCNA). GCPM-related hub lncRNAs and genes were identified by cytoHubba and validated by Quantitative real-time PCR (qRT-PCR), Receiver operating characteristic curve (ROC) analysis and Kaplan-Meier survival analysis. GO, KEGG and GSEA showed GCPM-related pathways. Correlation analysis revealed the potential relationship between hub lncRNAs and genes.ResultsBy analyzing lncRNA expression data by WGCNA, we found that blue module was highly correlated with GCPM (r = 0.44, p = 0.04) and six lncRNAs involved in this module (DNM3OS, lnc-MFAP2-53, lnc-PPIAL4C-4, lnc-RFNG-1, lnc-TRIM28-14 and lnc-YARS2-4) were identified. We then performed qRT-PCR validation of gastric cancer specimens and found that the expression of lnc-RFNG-1 and lnc-TRIM28-14 was significantly increased in gastric cancer tissues with peritoneal metastasis. Kaplan-Meier survival analysis showed shorter overall survival time (OS) for gastric cancer patients with high expression of lnc-TRIM28-14. Receiver operating characteristic curve (ROC) analysis showed that lnc-TRIM28-14 could improve the sensitivity and specificity of GCPM diagnosis. In addition, we identified three key mRNAs (CD93, COL3A1 and COL4A1) associated with gastric cancer peritoneal metastasis through WGCNA analysis and clinical specimen validation. Moreover, there was a positive correlation between lnc-TRIM28-14 and the expression of CD93 and COL4A1 in gastric cancer peritoneal metastasis, suggesting a regulatory relationship between them. Subsequent GO, KEGG and GSEA analysis suggested that ECM-receptor interaction and focal adhesion were the hub pathways of GCPM.ConclusionIn summary, lnc-RFNG-1, lnc-TRIM28-14, CD93, COL3A1 and COL4A1 could be novel tumor biomarkers and potential therapeutic targets for GCPM.

C5aR1 shapes a non-inflammatory tumor microenvironment and mediates immune evasion in gastric cancer.

C5a receptor 1 (C5aR1) is associated with various inflammatory processes, the pathogenesis of immune diseases, and tumor growth. However, its role in the tumor microenvironment of gastric cancer (GC) remains unclear. In this study, the expression of C5aR1 in GC and normal gastric mucosa tissues was compared using data retrieved from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases, and the results were validated by in vitro qRT-PCR and immunohistochemical analyses. The relationship between C5aR1 expression and the overall survival of patients with GC was analyzed using the Kaplan-Meier method. Subsequently, enrichment analysis was performed, and the signaling pathways were screened. C5aR1 expression was also correlated with genes related to the immune checkpoint and immune cell infiltration. The results revealed that C5aR1 expression was enhanced in GC tissues compared to normal gastric tissues, and that patients with high expression of C5aR1 had a worse 10-year overall survival compared to those showing low expression of C5aR1. Functional analysis revealed that C5aR1 is a gene related to theimmune system and may play a crucial role in inflammatory and tumor immune responses. Additionally, C5aR1 showed a positive correlation with most immune checkpoint-related genes and a negative correlation with natural killer cells, dendritic cells, and CD8+ T cells. Immune evasion risk was observed to be significantly greater in patients with higher expression of C5aR1 than in those with lower expression. The results of this study reveal that C5aR1 shapes a non-inflammatory tumor microenvironment in GC and mediates immune evasion.

Multiplexed immunofluorescence analysis of CAF-markers, EZH2 and FOXM1 in gastric tissue: associations with clinicopathological parameters and clinical outcomes

BackgroundThe aim of this study is to explore the expression and clinical relevance of CAF-associated markers, EZH2 and FOXM1 in gastric samples.MethodsProtein expression were detected and evaluated by multi-plex immunofluorescence (mIF) in 93 cases of gastric cancer (GC) and 31 cases of gastric intraepithelial neoplasia (GIN). The correlation among their expression, and the relationship of them with clinicopathological parameters and prognosis in GC were then analyzed.ResultsFAP was specific expressed in the CAFs of GC samples, and thus be utilized as a CAF-associated marker in our subsequently analysis. The immunostaining of EZH2, FOXM1 and FAP were significantly upregulated in patients with GC tissues than in those normal gastric mucosa or GIN tissues. The average fluorescence intensity of FAP was slightly positively correlated with EZH2 in GC, GIN and normal samples, whereas the percentage of FAP positive cells has no correlation with that of EZH2. Both the percentage of positive cells and the average fluorescence intensity of FOXM1 were positively correlated with that of FAP and EZH2 in GC, GIN and normal samples, except for FOXM1 and EZH2 expression in normal tissue samples. No significant association was observed between FAP expression and any clinicopathological parameters, whereas the positive frequency of EZH2 and FOXM1 were correlated with tumor location significantly and tumor invasion depth, respectively. In addition, there was strong positive correlations between FAP protein expression and overall survival (OS) and disease-free survival (DFS), and EZH2 expression was positively associated with OS in patients with GC. Furthermore, EZH2 and FAP protein expression was an independent prognostic factor for OS and DFS, respectively.ConclusionsThese results suggest that both EZH2 and FOXM1 expression was positively associated with CAFs abundance in GC. They may be potential cellular target for therapeutic intervention, especially in patients with a large number of CAFs.

Effects of Autologous Platelet-Rich Plasma on Healing of Peptic Ulcers: A Randomized Controlled Trial.

Purpose Peptic ulcer is a multifactorial and complex disease and affects a wide range of people worldwide. We provided a novel therapeutic approach for peptic ulcer and observed its effect. Methods Peptic ulcer patients were enrolled from 2016 to 2017 in Chongqing and randomly assigned to two groups: a control group that used only rabeprazole and a platelet-rich plasma (PRP) group that received a combination therapy of autologous PRP (aPRP) and rabeprazole. The therapeutic effect was assessed via the ulcer size and symptom score. Results A total of 27 patients were included (12 patients in the control group and 15 patients in the PRP group) in this study. Our results showed that all participants have healed in 30 days, and there was no significant difference in healing time between the PRP group and the control group in different independent variables. However, regression analysis revealed that the healing time was 6.99 days shorter in the PRP group than that in the control group, and patients with higher symptom scores in the initial examination need more time to heal during treatment. Endoscopic results showed that the repaired ulcer in the PRP group was more similar to the normal gastric mucosa tissue than that the control group. Conclusion This study showed an encouraging preliminary result that aPRP has a positive result in patients with peptic ulcer and seems to be a better choice for refractory peptic ulcer treatment. Although further follow-up studies are needed to determine the duration of efficacy of aPRP, the approach will be helpful in improving the clinical treatment of peptic ulcer.

LncRNA HIT000218960 enhances resistance to 5-fluorouracil by promoting HMGA2 and activating the AKT/mTOR/P70S6K pathway in gastric cancer cells.

The aim of the present study was to investigate the effect of the long noncoding RNA HIT000218960 on gastric cancer cell resistance to 5-fluorouracil (5-FU) and to explore the underlying molecular mechanism. HIT000218960 expression was measured in gastric cancer tissues and cells lines using reverse transcription-quantitative PCR and western blotting. Gastric cancer cell lines with overexpressed or repressed HIT000218960 levels were generated to study its influence on apoptosis induced by 5-FU, which was analyzed using flow cytometry analysis. Compared with those in normal gastric mucosal tissues and non-cancerous gastric mucosal epithelial cells, HIT000218960 and high mobility group A2 (HMGA2) proteins were found to be upregulated in gastric cancer tissues and cells. Additionally, a positive correlation was found between the expression of HIT000218960 and HMGA2 in gastric cancer tissues. In patients with gastric cancer, HIT000218960 expression was revealed to associate negatively with the efficacy of chemotherapy and 3-year overall survival rate. Overexpression of HIT000218960 suppressed apoptosis in SNU-5 cells, whilst HIT000218960 knockdown increased the apoptosis of NCI-N87 cells following 5-FU treatment. Downstream, HIT000218960 was demonstrated to promote HMGA2 protein expression in gastric cancer cells. In these cells, knocking down HMGA2 expression significantly increased apoptosis in addition to reducing AKT, mTOR and P70S6 kinase (P70S6K) phosphorylation after 5-FU treatment. In conclusion, HIT000218960 is overexpressed in gastric cancer tissues and cells, which is associated with the efficacy of chemotherapy. Mechanistically, this may be mediated by the upregulation HMGA2 expression and AKT/mTOR/P70S6K signaling.

Characterization of the Prognostic Values of CXCL Family in Epstein-Barr Virus Associated Gastric Cancer.

Background CXCL family is a class of secreted growth factors signaling through G-protein-coupled receptors, and abnormal expression is associated with the growth and progression of many tumors. However, their prognostic value has been poorly studied in Epstein–Barr virus- (EBV-) associated gastric cancer (EBVaGC). Therefore, it is of great significance to explore the prognostic value of the CXCL family in EBVaGC. Methods CXCL family mRNA expression was analyzed in STAD data from The Cancer Genome Atlas (TCGA). Kaplan-Meier Plotter was used to assess the prognostic value of the CXCL family. Transcription factors (TFs) and miRNAs associated with the CXCL family were identified by TFCheckpoint, miRWalk, and ViRBase databases. The prognostic model was evaluated using the EBVaGC patient cohort GSE51575. Results The mRNA expression of CXCL1/3/5/6/8/9/10/11/16 was significantly upregulated, while the expression of CXCL12/14 was downregulated in EBVaGC compared with normal tissues from TCGA-STAD. The mRNA expressions of CXCL9, CXCL10, CXCL11, and CXCL17 in EBVaGCs were higher than those in EBVnGCs, but the mRNA expressions of CXCL6, CXCL12, and CXCL17 were lower than those in EBVnGCs. The mRNA expression levels of CXCL9, CXCL10, and CXCL11 in EBVaGCs were higher than those in EBVnGCs regardless of the tumor stage. High mRNA expression of CXCL8 was associated with better OS in patients with EBVaGC, while high expression of CXCL9 was associated with better OS in patients with EBVnGC. We obtained 10 candidate potential transcription factors (TFs) associated with CXCLs: OTOP3, NKX6-2, NKX2-2, FEV, SMYD1, TRIMSO, TBX10, CDX1, SLC26A3, and ARC. 576 miRNA-mRNA interactions were obtained. Among them, 65 miRNAs were predicted to be correlated with CXCL6, CXCL9, CXCL10, and CXCL11. Similar to the results of TCGA-STAD, the GSE51575 dataset also showed that the mRNA expression levels of CXCL1/3/9/10/11/16 were markedly enhanced in EBVaGC tissues compared with corresponding normal gastric mucosa tissues, while the mRNA expression levels of CXCL12/14 were significantly reduced. The mRNA expression levels of CXCL3/9/10/11/13/17 were increased in EBVaGC compared with EBVnGC tissues. Conclusions The expression differences of CXCL family members are closely associated with the progression of EBVaGC. Expression of CXCL9/10/11/17 mRNA may be a promising prognostic indicator for EBVaGC patients.

Prognosis of gastric adenocarcinoma associated with girdin, Akt, and cortactin.

BACKGROUND: The actin-binding protein girdin regulates tumor cell migration and invasion by maintaining actin structure. PI3K/Akt signaling is an important actin-remodeling pathway. The protein cortactin acts directly on microfilaments and promotes tumor invasion and metastasis by rearranging the cytoskeleton. However, there are few reports on the co-expression of girdin, Akt, and cortactin in gastric adenocarcinoma (GAC).OBJECTIVES: Evaluate girdin, Akt, and cortactin expression in GAC tissues and assess their relationship to the prognosis of GAC patients.DESIGN: Survival analysisSETTING: Medical college in ChinaPATIENTS AND METHODS: We compared survival in 110 paraffin-preserved GAC with corresponding normal gastric mucosa tissues in relationship to girdin, Akt, and cortactin expression levels.MAIN OUTCOME MEASURE: Expression levels of the proteins.SAMPLE SIZE: 110RESULTS: The expression of girdin, Akt, and cortactin were all upregulated in GAC tissues compared with corresponding normal tissues (66.4% vs 36.3%, 57.3% vs 28.2% and 69.1% vs 22.7%, respectively; P<.05) and expression was mutually positive (all P<.05). Overall survival in the girdin, Akt, and cortactin high expression groups was reduced. Multivariate analysis showed that girdin, Akt, cortactin, lymph node metastasis (LNM) and TNM stages were independent factors affecting GAC patients prognosis (P<.05).CONCLUSIONS: Girdin and cortactin may promote GAC invasion and metastasis via the PI3-K/Akt signaling pathway. Girdin, Akt, and cortactin co-expression might serve as a novel molecular target for GAC therapy and improve the prognosis of patients with this disease.LIMITATIONS: A small sample size and lack of related research on molecular mechanisms.CONFLICT OF INTEREST: None.

MiR-4484 regulates the expression of integrin α 6 in gastric cancer tissues and its significance

Objective: To investigate the relationship between the expression of integrin α 6 (ITGA6), miR-4484 and the pathologic stage of gastric cancer. Methods: Gastric cancer tissues and normal gastric mucosa tissues adjacent to cancer (>5 cm from tumor margin) of 30 patients with primary gastric cancer who underwent direct surgical resection without adjuvant therapy from June to September 2017 in West China Hospital of Sichuan University were selected. Real-time quantitative polymerase chain reaction (PCR) was used to detect the expression levels of miR-4484 and ITGA6, western blot was used to detect the expression level of ITGA6 protein, dual luciferase reporter gene was used to verify the relationship between ITGA6 and miR-4484. Spearman's correlation analysis was used to determine the relationship between miR-4484 and ITGA6 expression levels in gastric cancer tissues. Results: The expression level of ITGΑ6 in gastric cancer (32.30±13.47) was higher than that in matched normal gastric tissues (24.55±10.25, P=0.015), the area under the receiver operating characteristic (ROC) curve was 0.660 and the diagnostic sensitivity and specificity were 43.3% and 96.7%, respectively. The expression level of miR-4484 in gastric cancer (4.11±2.87) was lower than that of matched normal gastric tissues (5.75±2.80, P=0.029), the area under the ROC curve was 0.690 and the diagnostic sensitivity and specificity were 30.0% and 86.7%, respectively. The expression level of miR-4484 was negatively correlated with ITGA6 in gastric cancer tissues (r=-0.621, P<0.001). The expression level of ITGA6 protein in gastric cancer tissues (0.65±0.19) was higher than that in normal adjacent tissues (0.26±0.12, P<0.001). Compared with ITGA6 3'UTR wild-type+ miR-NC group, ITGA6 3'UTR wild-type+ miRNA mimics group had lower luciferase activity (50.69±5.10, 34.00±1.19, P<0.001), while the luciferase activity of ITGA6 3'UTR wild-type+ ASO miR-4484 group was higher than that of ITGA6 3'UTR wild-type+ miR-NC group (82.44±6.37, 50.69±5.10, P<0.001), indicated that ITGA6 was the direct target gene of miR-4484. The expression levels of miR-4484 in T1, T2, T3 and T4 (4a and 4b) gastric cancer tissues were 9.98±2.24, 5.28±2.03, 2.92±2.04 and 4.11±2.87, respectively, with statistical significance (P<0.001). The expression levels of ITGA6 in N0, N1, N2 and N3 gastric cancer tissues were 29.55±8.32, 21.71±3.75, 24.60±8.79 and 40.69±15.83, respectively, with statistical significance (P=0.022). The expression levels of miR-4484 in N0, N1, N2 and N3 gastric cancer tissues were 5.01±3.52, 5.48±2.76, 5.88±1.83 and 2.30±1.56, respectively, with statistical significance (P=0.032). The expression levels of ITGA6 in M0 and M1 gastric cancer tissues were 26.28±7.66 and 52.08±8.12, respectively, with statistical significance (P<0.001). The expression levels of miR-4484 in M0 and M1 gastric cancer tissues were 4.95±2.74 and 1.34±0.80, respectively, with statistical significance (P<0.001). Conclusions: ITGA6 is upregulated in gastric cancer tissues, while miR-4484 is downregulated in the gastric cancer group, and its expression level is related to the clinicopathological features of gastric cancer. ITGA6 is the direct target gene of miR-4484, implicates that miR-4484 may inhibit the invasion and metastasis of gastric cancer by regulating the expression of ITGA6. Both miR-4484 and ITGA6 may be the new prognostic markers and potential therapeutic targets of gastric cancer.

Overexpression of IL-8 and Wnt2 is associated with prognosis of gastric cancer.

This study is to detect the expression of inflammatory factor or neutrophil-activating factor IL-8 and Wnt2 in gastric cancer (GC) and investigate the involvement of IL-8 and Wnt2 expressions in the clinicopathological indexes and prognosis. We detected the expression of IL-8 and Wnt2 in 100 GC tissues and 40 normal gastric mucosae using immunohistochemistry. The relationships between the IL-8 and Wnt2 expression and the clinicopathological characteristics were explored. The relationship between IL-8 expression, Wnt2 expression, and prognosis of GC was analyzed by survival curve and survival regression. The expression of IL-8 and Wnt2 in GC tissue was 64% and 75% respectively, which was significantly higher than that in adjacent normal gastric mucosa tissues, moreover, expressions of IL-8 and Wnt2 were positively correlated. The positive rate of IL-8 and Wnt2 expressions were correlated with lymph node metastasis and TNM staging （P < 0.01, and Wnt2 was also correlated with infiltration depth (P = 0.021), but there was no difference with age, sex, and differentiation (P > 0.05). The 3-year survival analysis showed that the survival rates of IL-8- and Wnt2-positive patients were 20% and 24%, respectively, which were significantly lower than those of negative patients. Cox regression analysis showed that IL-8 and Wnt2 may be independent factors affecting the prognosis of GC. Our data demonstrated that the overexpression of IL-8 and Wnt2 could be isolated prognostic factors in patients with GC and, possibly, may present new targets for the treatment of GC.

Characterization of E-cadherin expression in normal mucosa, dysplasia and adenocarcinoma of gastric cardia and its influence on prognosis.

BACKGROUNDGastric cardia adenocarcinoma (GCA), which has been classified as type II adenocarcinoma of the esophagogastric junction in western countries, is of similar geographic distribution with esophageal squamous cell carcinoma in China, and even referred as "sister cancer" by Chinese oncologists. The molecular mechanism for GCA is largely unknown. Recent studies have shown that decreased expression of E-cadherin is associated with the invasion and metastasis of multiple cancers. However, the E-cadherin expression has not been well characterized in gastric cardia carcinogenesis and its effect on GCA prognosis.AIMTo characterize E-cadherin expression in normal gastric cardia mucosa, dysplasia and GCA tissues, and its influence on prognosis for GCA.METHODSA total of 4561 patients with GCA were enrolled from our previously established GCA and esophageal cancer databases. The enrollment criteria included radical surgery for GCA, but without any radio- or chemo-therapy before operation. The GCA tissue from 4561 patients and matched adjacent normal epithelial tissue (n = 208) and dysplasia lesions (n = 156) were collected, and processed as tissue microarray for immunohistochemistry. The clinicopathological characteristics were retrieved from the medical records in hospital and follow-up was carried out through letter, telephone or home interview. E-cadherin protein expression was determined by two step immunohistochemistry. Kaplan–Meier and Cox regression analyses were used to correlate E-cadherin protein expression with survival of GCA patients.RESULTSOf the 4561 GCA patients, there were 3607 males with a mean age of 61.6 ± 8.8 and 954 females with a mean age of 61.9 ± 8.6 years, respectively. With the lesions progressed from normal gastric cardia mucosa to dysplasia and GCA, the positive immunostaining rates for E-cadherin decreased significantly from 100% to 93.0% and 84.1%, respectively (R2 = 0.9948). Furthermore, E-cadherin positive immunostaining rate was significantly higher in patients at early stage (0 and I) than in those at late stage (II and III) (92.7% vs 83.7%, P = 0.001). E-cadherin positive expression rate was significantly associated with degree of differentiation (P = 0.001) and invasion depth (P < 0.001). Multivariate analysis showed that the GCA patients with positive E-cadherin immunostaining had better survival than those with negative (P = 0.026). It was noteworthy that E-cadherin positive expression rate was similar in patients with positive and negative lymph node metastasis. However, in patients with negative lymph node metastasis, those with positive expression of E-cadherin had better survival than those with negative expression (P = 0.036). Similarly, in patients with late stage GCA, those with positive expression of E-cadherin had better survival than those with negative expression (P = 0.011). CONCLUSIONE-cadherin expression may be involved in gastric cardia carcinogenesis and low expression of E-cadherin may be a promising early biomarker and overall survival predictor for GCA.

The upregulation of proteins light chain 3 and autophagy-related 5 and the occurence of intestinal-type gastric cancer.

This study aims to investigate the expression levels and values of autophagy genes light chain 3 (LC3) and autophagy-related 5 (ATG5) in intestinal-type gastric cancer. Ninety samples of normal gastric mucosa, intraepithelial neoplasia, and gastric cancer tissue were used in this study. The messenger ribonucleic acid (mRNA) and protein expression levels of autophagy genes LC3 and ATG5 were detected using quantitative reverse transcription polymerase chain reaction, Western blot, and the immunohistochemistry method. The correlations of the autophagy genes and certain clinical pathological parameters were analyzed. The results showed that LC3 mRNA expression was 43.76 ± 20.31 in the normal group, 111.29 ± 18.65 in the intraepithelial neoplasia group, and 131.78 ± 26.29 in the gastric cancer group, while ATG5 mRNA expression was 4.52 ± 2.37 in the normal group, 7.09 ± 1.88 in the intraepithelial neoplasia group, and 10.25 ± 2.81 in the gastric cancer group. The differences between the groups were statistically significant (P < 0.05). The protein expression of LC3 in the normal group was 1.05 ± 0.41, 1.53 ± 0.36 in the intraepithelial neoplasia group, and 1.99 ± 0.14 in the gastric cancer group. The protein expression of ATG5 was 0.78 ± 0.24 in the normal group, 1.37 ± 0.39 in the intraepithelial neoplasia group, and 2.04 ± 0.63 in the gastric cancer group. The differences between the groups were statistically significant (P < 0.05). The positive rate of LC3 protein expression was 33.3% in the normal group and 60% in the intraepithelial neoplasia group, and the difference was statistically significant (χ2 = 4.89; P = 0.04). In the gastric cancer group, the positive rate of LC3 protein expression was 83.3%, making it significantly higher than the intraepithelial neoplasia group, with a statistically significant difference (χ2 = 4.02, P = 0.045). The positive rate of ATG5 protein expression was 23.3% in the normal group, 50.0% in the intraepithelial neoplasia group, and 76.7% in the gastric cancer group. The expression in the intraepithelial neoplasia group was much higher than in the normal group, with a statistically significant difference (χ2 = 4.59, P = 0.03), and that of the gastric cancer group was much higher than that of the intraepithelial neoplasia group, with a statistically significant difference (χ2 = 4.59, P = 0.03). LC3 protein expression was significantly correlated with depth of infiltration, and lymph node status. ATG5 protein expression was significantly correlated with age, depth of infiltration, and lymph node status. There was also a correlation between the LC3 and ATG5 proteins (correlation coefficient r = 0.72, P = 0.001). The enhanced autophagy activity of LC3 and ATG5 may participate in the occurrence and development of intestinal gastric cancer, and they may play a synergistic role in promoting the occurrence and development of intestinal gastric cancer. These findings provide clinical value for the diagnosis of intestinal gastric cancer.

Expression of hepatocyte nuclear factor 4γ in gastric carcinoma and its role in cell proliferation and stemness

Objective: To explore the role and molecular mechanism of hepatocyte nuclear factor 4γ (HNF4γ) in proliferation and stemness of gastric cancer. Methods: A total of 102 cases of paraffin-embedded gastric cancer tissues and matched adjacent gastric tissues and 42 cases of fresh-frozen tissues derived from gastric patients who received radical gastrectomy were collected from the First Affiliated Hospital of Zhengzhou University between 2012 to 2015. The expression of HNF4γ was tested by immunohistochemical staining, quantitative real-time polymerase chain reaction (qRT-PCR). HNF4γ overexpressed (AGS-HNF4γ) and shRNA silenced (HGC27-shHNF4γ) gastric cell lines were established. The effects of HNF4γ on cell proliferation and stemness were verified by XTT, clone formation and sphere formation assay. The expression of CD44 was detected by western blot. Results: The mRNA expression level of HNF4γ in fresh-frozen gastric cancer tissue was (12.43±2.702), which was significantly higher than (3.639±1.109) in normal tissue (P<0.001). The high protein expression rate of HNF4γ in paraffin-embedded gastric cancer tissues was 41.2% (42/102), which was significantly higher than 8.8% (9/102) in normal gastric mucosa tissue (P< 0.001). The protein expression of HNF4γ was closely related to the tumor differentiation, infiltration depth, lymph node metastasis and tumor stage (P<0.05). The median survival interval of patients with HNF4γ high expression was 25 months, the 3-year survival rate was 4.8% (2/42), significantly lower than 38 months and 51.7% (31/60) of patients with normal HNF4γ expression (P<0.001). The proliferation and CD44 protein expression of AGS-HNF4γ cells were significantly higher than those of the AGS-Vector cells. The number of clone formation, sphere formation rate of AGS-HNF4γ cells were 243.5±24.5 and (83.5±3.9)%, significantly higher than 81.0±16.0 and (21.8±5.6)% of AGS-Vector cells (P=0.030 and P=0.010, respectively). The proliferation and CD44 protein expression of HGC27-shHNF4 cells were significantly lower than those of the HGC27-vector cells. The number of clone formation, sphere formation rate of HGC27-shHNF4 cells were 26.0±1.0 and (20.8±8.4)%, significantly higher than 83.5±4.5 and (72.5±4.8)% of HGC27-vector cells (P=0.006 and P=0.030, respectively). Conclusions: HNF4γ is upregulated in the gastric cancer tissues and related with the poor prognosis of patients with gastric cancer. Overexpression of HNF4γ promotes the proliferation and remains the stemness of gastric cancer cells by upregulating the expression of CD44.