The value of lymph nodes ratios in the prognosis of resectable remnant gastric cancer through the retrospective propensity score matching analysis.

PURPOSE: Currently, the characteristics and prognosis of remnant gastric cancer (RGC) are not fully understood yet. The present study aimed to describe the details of clinicopathological features of resectable RGC and investigated the factors affecting survival after the curative operation. METHODS: From Jan. 2006 to Dec. 2015, a total of 118 resectable RGC patients (the RGC group) and 236 age-, sex- and TNM stages-matched resectable gastric cancer (GC) patients (the control group) were recruited retrospectively. Clinicopathological characteristics and overall survival were compared between the two groups. RESULTS: The overall survival rate was 46.61% for RGC patients compared to 55.08% for control groups (P < 0.01), and the mean overall survival time of RGC patients was 40.23 ± 32.27 months, compared to 55.06 ± 34.29 months in the control group (P = 0.023 after matching). The overall survival (OS) of RGC patients with stage IIb was much worse than IIa (P < 0.001) and similar to IIIa (P = 0.463) and IIIb (P = 0.014). Multivariate Cox proportional hazards model analysis revealed that TNM stage (HR: 3.899, P < 0.001) and lymph nodes ratio (LNR) (HR: 2.405, P = 0.028) were independent prognostic significance to OS. CONCLUSIONS: The OS of RGC was much worse than GC with similar TNM stages, and LNR might consider a highly reliable indicator to evaluate the prognostic in RGC.

Endothelial-Related Biomarkers in Evaluation of Vascular Function During Progression of Sepsis After Severe Trauma: New Potential Diagnostic Tools in Sepsis.

Purpose: This study aimed to investigate the changes in endothelial-related biomarkers and their relationship with the incidence and prognosis of patients with sepsis after severe trauma. Methods: A total of 37 severe trauma patients admitted to our hospital from Jan. to Dec. 2020 were enrolled in our research. All enrolled patients were divided into the sepsis and the non-sepsis groups. Endothelial progenitor cells (EPCs), circulating endothelial cells (CECs), and endothelial microparticles (EMPs) were detected on admission time; 24-48 hours and 48-72 hours after admission respectively. Demographic data, Acute Physiology, Chronic Health Evaluation (APACHE) II, and Sequential Organ Failure Assessment (SOFA) score were calculated every 24 h of admission to assess the severity of organ dysfunction. Receiver operating characteristic (ROC) curves were drawn to compare the areas under the curve (AUC) of endothelial-related biomarkers for the diagnosis of sepsis. Results: The incidence rate of sepsis was 45.95% in all patients. The SOFA score in the sepsis group was significantly higher than that in the non-sepsis group (2 points vs 0 points, P<0.01). The number of EPCs, CECs, and EMPs all rose quickly in the early phase after trauma. The number of EPCs was similar in both groups, but the number of CECs and EMPs in the Sepsis Group was much higher than in the non-Sepsis Group (all P<0.01). Logistic regression analysis showed that the occurrence of sepsis was closely related to the expression of 0-24h CECs and 0-24h EMPs. The AUC ROC for CECs in different time periods were 0.815, 0.877, and 0.882, respectively (all P<0.001). The AUC ROC for EMPs in 0-24h was 0.868 (P=0.005). Conclusion: The expression of EMPs was higher in early severe trauma, and high levels of EMPs were significantly higher in patients with early sepsis and poor prognosis.

LncRNA NEAT-2 regulate the function of endothelial progenitor cells in experimental Sepsis model.

BACKGROUND: Sepsis is a life-threatening disease with a limited effectiveness and the potential mechanism remains unclear. LncRNA NEAT-2 is reported to be involved in the regulation of cardiovascular disease. This study aimed to investigate the function of NEAT-2 in sepsis. METHODS: We built sepsis animal model with Male Balb/C mice induced by cecal ligation and puncture (CLP). A total of 54 mice were randomly assigned into eight groups: sham operation group (n = 18), CLP group (n = 18), CLP plus si-control group (n = 3), CLP plus si-NEAT2 group (n = 3), CLP plus mimic control group (n = 3), CLP plus miR-320 group (n = 3), CLP plus normal saline group (n = 3), and normal control group (n = 3). The number of peripheral endothelial progenitor cells (EPCs), the expression level of NEAT-2 and miR-320 were detected during progression of sepsis, as well as the number of peripheral EPCs and level of TNF-α, IL-6, VEGF, ALT, AST and Cr. In addition, the function of EPCs was evaluated after NEAT-2 knockdown and miR-320 overexpression in vitro. RESULTS: The number of circulating EPCs increased significantly in sepsis. NEAT-2 expression was significantly increased in the progress of sepsis, accompanied with miR-320 downregulated. NEAT-2 knockdown and miR-320 overexpression attenuated hepatorenal function and increased cytokines in sepsis. Moreover, NEAT-2 knockdown and miR-320 overexpression decreased the proliferation, migration and angiogenesis of endothelial progenitor cells in vitro. CONCLUSIONS: LncRNA-NEAT2 regulated the number and function of endothelial progenitor cells via miR-320 in sepsis, which may contribute to the development of novel potential clinical therapy for sepsis.

Analysis of risk factors and prevention strategies for functional delayed gastric emptying in 1243 patients with distal gastric cancer.

BACKGROUND: Analysis of the risk factors associated with functional delayed gastric emptying after distal gastric cancer surgery to provide a basis for further reduction of the incidence of this complication. METHODS: Total of 1382 patients with distal gastric cancer from January 2016 to October 2018 were enrolled. Correlation analysis was performed in 53 patients with FDGE by logistic regression. Subgroup risk analysis was performed in 114 patients with preoperative pyloric obstruction. A Pearson Chi-square analysis was used to compare categorical variables between normal distribution groups. Meanwhile, a t test was used to compare continuous variables between groups. Odds ratio (OR) was used for comparison of the two groups, and it was summarized with its 95% confidence interval (CI) and p value using logistic regression. RESULT: In multivariable analysis, age (OR 1.081, 95% CI, 1.047-1.117), BMI (OR 1.233, 95% CI, 1.116-1.363), preoperative pyloric obstruction (OR 3.831, 95% CI, 1.829-8.023), smaller volume of residual stomach (OR 1.838, 95% CI, 1.325-6.080), and anastomosis in greater curvature perpendicular (OR 3.385, 95% CI, 1.632-7.019) and in greater curvature parallel (OR 2.375, 95% CI, 0.963-5.861) were independent risk factors of FDGE. In the preoperative pyloric obstruction group, higher BMI (OR 1.309, 95% CI, 1.086-1.579) and preoperative obstruction time (OR 1.054, 95% CI, 1.003-1.108) were independent risk factors of FDGE and preoperative gastrointestinal decompression (OR 0.231, 95% CI, 0.068-0.785) was independent protective factor of FDGE. CONCLUSION: Adequate gastrointestinal decompression should be performed before the operation to reduce the incidence of postoperative gastroparesis in patients with preoperative pyloric obstruction. We also could improve the surgical methods to reduce the occurrence of FDGE, such as controlling the size of the residual stomach, ensuring blood supply. Especially selecting an appropriate stapler and anastomosis during the anastomosis process, the occurrence of FDGE can be reduced.

Delivery of TSPAN1 siRNA by Novel Th17 Targeted Cationic Liposomes for Gastric Cancer Intervention.

Several studies focus on the relationship between immune cells in the tumor microenvironment and tumor cells. Th17 cells, a naïve CD4+ T cell subtype, secrete IL-17 cytokines that further the progression and metastasis of tumors, such as gastric cancer, which is a leading cause of cancer-related death worldwide. Moreover, previous studies have demonstrated that the polarization ratio of CD4+ T cells to Th17 cells is closely related to the Tetraspanin 1 (TSPAN1) protein. Therefore, in this study, we designed a novel Th17 antibody-modified liposome polycation-DNA complex (LPD) encapsulated with TSPAN1 small interfering RNA (siRNA) (Th17-LPDT), to decrease the polarization of CD4+ T cells, and thereby inhibit the development of gastric cancer. Our in vitro results demonstrated the decrease in CD4+ T cells polarization to Th17 cells follwing Th17-LPDT treatment. Furthermore, in vivo data proved that Th17-LPDT treatment significantly inhibits the formation of gastric tumors. We believe that Th17-LPDT is a promising targeted nanoparticle drug for the clinical treatment of gastric cancer and this study provides a new strategy for tumor intervention.

Development and validation of a nomogram for preoperative prediction of lymph node metastasis in early gastric cancer.

BACKGROUND: The status of lymph nodes in early gastric cancer is critical to make further clinical treatment decision, but the prediction of lymph node metastasis remains difficult before operation. This study aimed to develop a nomogram that contained preoperative factors to predict lymph node metastasis in early gastric cancer patients. METHODS: This study analyzed the clinicopathologic features of 823 early gastric cancer patients who underwent gastrectomy retrospectively, among which 596 patients were recruited in the training cohort and 227 patients in the independent validation cohort. Significant risk factors in univariate analysis were further identified to be independent variables in multivariable logistic regression analysis, which were then incorporated in and presented with a nomogram. And internal and external validation curves were plotted to evaluate the discrimination of the nomogram. RESULTS: Totally, six independent predictors, including the tumor size, macroscopic features, histology differentiation, P53, carbohydrate antigen 19-9, and computed tomography-reported lymph node status, were enrolled in the nomogram. Both the internal validation in the training cohort and the external validation in the validation cohort showed the nomogram had good discriminations, with a C-index of 0.82 (95%CI, 0.78 to 0.86) and 0.77 (95%CI, 0.60 to 0.94) respectively. CONCLUSIONS: Our study developed a new nomogram which contained the most common and significant preoperative risk factors for lymph node metastasis in patients with early gastric cancer. The nomogram can identify early gastric cancer patients with the high probability of lymph node metastasis and help clinicians make more appropriate decisions in clinical practice.

Cancer-associated fibroblasts promote malignancy of gastric cancer cells via Nodal signalling.

The roles of cancer-associated fibroblasts (CAFs) in progression of gastric cancer (GC) are far from well illustration. Here, we show that CAFs can trigger the proliferation and decrease the doxorubicin (Dox) sensitivity of GC cells via secretion of Nodal, one embryonic morphogen that can promote malignancy of various cancers. The neutralization antibody of Nodal can attenuate CAFs-induced cell proliferation. Further, CAFs can activate the Smad2/3 signal, which further increase the phosphorylation and nuclear localization of Akt, in GC cells. While anti-Nodal can abolish the CAFs-induced activation of Smad2/3/Akt signals. Further, both inhibitors of Smad2/3 and Akt can attenuate CAFs-induced proliferation of GC cells. All these data suggest that CAFs can increase the malignancy of GC cells via Nodal-induced activation of Smad2/3/Akt signals. It indicates that CAFs/Nodal signals might be a potential new target of clinical interventions for GC patients. SIGNIFICANCE OF THE STUDY: The roles about CAFs in progression of GC are not well illustrated. Our present study reveals that CAFs can increase the proliferation and decrease the Dox sensitivity of GC cells via secretion of Nodal. The secreted Nodal further activated Samd2/3/Akt signals to trigger the GC progression. It suggests that targeted inhibition CAFs/Nodal might be a potential approach for GC therapy.

MALAT1 promotes gastric adenocarcinoma through the MALAT1/miR-181a-5p/AKT3 axis.

Gastric adenocarcinoma, which originates from the gastric mucosal epithelium, has the highest incidence among various malignant tumours in China. As a crucial long non-coding RNA, metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) has been suggested to play an important role in many tumours. Here, we aimed to investigate the role and underlying mechanism of MALAT1 in gastric adenocarcinoma. Quantitative reverse transcription polymerase chain reaction was applied to determine the expression levels of MALAT1 in serum and cell lines. A CCK-8 assay and a clonogenic survival assay were used to examine cell proliferation and apoptosis. The protein level of RAC-γ serine/threonine-specific protein kinase (AKT3) was determined by western blot. Our results showed that MALAT1 was highly expressed in the serum of patients with gastric adenocarcinoma and in cell lines. Downregulating MALAT1 inhibited proliferation and promoted apoptosis of MGC-803 cells. In addition, MALAT1 directly targeted and decreased the expression of miR-181a-5p, which in turn upregulated the expression of AKT3. Further, overexpressing miR-181a-5p or directly inhibiting the AKT pathway with the inhibitor ipatasertib exhibited similar effects to MALAT1 knockdown. Our research proposes a novel mechanism where the role of MALAT1 is dependent on the MALAT1/miR-181a-5p/AKT3 axis. MALAT1 competes with AKT3 for miR-181a-5p binding, thereby upregulating the AKT3 protein level and ultimately promoting the growth of gastric adenocarcinoma.

Potential Role of Caveolin-1 in Regulating the Function of Endothelial Progenitor Cells from Experimental MODS Model.

Multiple organ dysfunction syndrome (MODS) remains a great challenge in critical care because of its common occurrence, high cost of care, and high mortality. Vascular endothelial injury is the initiation step in the development of MODS, and EPCs are essential for the process of organ repair. It is unclear whether and how caveolin-1 (Cav-1) in EPCs contributes to the pathogenesis of MODS. The present study is aimed at investigating the potential role of Cav-1 in EPCs during MODS. We established a MODS model in pigs, isolated and characterized EPCs from the MODS model, and tracked Cav-1 expression and various in vitro behaviors of EPCs from the MODS model. Then, we knockdown Cav-1 expression with siRNA or induce Cav-1 expression with proinflammatory factors to evaluate potential effects on EPCs. Our results suggest that Cav-1 expression correlated with EPC functions during MODS and Cav-1 regulates the function of endothelial progenitor cells via PI3K/Akt/eNOS signaling during MODS. Thus, Cav-1 in EPCs could be an attractive target for the treatment of MODS.

Targeted eradication of gastric cancer stem cells by CD44 targeting USP22 small interfering RNA-loaded nanoliposomes.

AIM: USP22, a member of ubiquitin-specific proteases (USPs), is a well-defined protein that promotes poor prognosis, invasion and metastasis, and also participates in the maintenance of cancer stem cells. USP22 siRNA-loaded nanoliposomes conjugated with CD44 antibodies (USP22-NLs-CD44) were constructed to enhance the therapeutic effect of USP22 siRNA against gastric cancer stem cells. MATERIALS & METHODS: The targeting and therapeutic efficacies of USP22-NLs-CD44 against gastric cancer stem cells were evaluated. RESULTS & CONCLUSION: USP22-NLs-CD44 was demonstrated to be able to effectively deliver USP22 siRNA to CD44+ gastric cancer stem cells, achieving superior therapeutic effects against CD44+ gastric cancer stem cells than nontargeted nanoliposomes. USP22-NLs-CD44 may provide a novel approach to eradicate gastric cancer stem cells in the near future.

SATB1 siRNA-encapsulated immunoliposomes conjugated with CD44 antibodies target and eliminate gastric cancer-initiating cells.

Purpose: Gastric cancer, the cancer initiated from the stomach, is ranked as the third most frequent reason of cancer death worldwide. Gastric cancer-initiating cells (CICs) are one of the crucial causes for the metastasis and recurrence of gastric cancer, and CD44 is considered to be one marker for gastric CICs. Special AT-rich sequence binding protein 1 (SATB1) is a protein that promotes cancer progression, metastasis, and invasion and also participates in the maintenance of CICs. In this study, we investigated the therapeutic effect of SATB1 siRNA against gastric CICs and we constructed SATB1 siRNA-encapsulated immunoliposomes conjugated with CD44 antibodies (CD44-SATB1-ILs) to enhance the therapeutic effect of SATB1 siRNA against gastric CICs. Methods: We investigated the therapeutic effect of the SATB1 suppression by SATB1 siRNA on CD44+ gastric CICs. CD44-SATB1-ILs were developed by the lyophilization/hydration approach. The targeting and cytotoxic effect of CD44-SATB1-ILs toward gastric CICs were evaluated in vitro. Results: In this study, for the first time, we confirmed that SATB1 suppression by SATB1 siRNA preferentially eliminated CD44+ gastric CICs. The results showed that CD44-SATB1-ILs could efficiently and specifically promote the SATB1 siRNA delivery to CD44+ gastric CICs, achieving superior therapeutic effects against CD44+ gastric CICs than non-targeted liposomes. Conclusion: As far as we know, our report is the first research that indicated the promotion of siRNA delivery via nanoparticles to gastric CICs and achievement of superior therapeutic effect against gastric CICs by utilization of CD44 antibody. Therefore, CD44-SATB1-ILs represent an up-and-coming approach for eliminating gastric CICs and also a promising treatment for therapy of gastric cancer.

Characterization of long non-coding RNAs and MEF2C-AS1 identified as a novel biomarker in diffuse gastric cancer.

Previous studies proved that long noncoding RNAs (lncRNAs) play important role in human cancer. However, the knowledge of genome scale expression of lncRNAs and their potential biological function in gastric cancer is still lacking. Next generation RNA sequencing (RNA-seq) was performed on tumor tissues and matched adjacent normal tissues of six diffuse gastric cancer (DGC) patients. Then we performed a comprehensive analysis on lncRNAs and mRNA. Fifty-eight lncRNAs were upregulated and 54 lncRNAs were downregulated in diffuse gastric cancer tissue compared with adjacent tissue. The numbers of up- and downregulated mRNAs were 306 and 161, respectively. In addition, we inferred the function of lncRNAs by construction of a co-expression network for deregulated mRNAs and lncRNAs. Co-expressed genes of MEF2C-AS1 and FENDRR were enriched to RAS and TGF-beta signaling pathway. MEF2C-AS1 and FENDRR expression were re-evaluated by Real-time Quantitative PCR in 42 DGC patients' tumor and normal tissues, and other 46 DGC patents' and 21 healthy controls' plasma. Validation data showed MEF2C-AS1 and FENDRR were significantly downregulated in tumor tissues compared with normal tissues. And decreased FENDRR are associated with aggressive tumor characteristics including more advanced stage (P = .030), poor differentiation (P = .043) and lymphatic metastasis (P = .001). The expression level MEF2C-AS1 was significantly lower in DGC patients' plasma than that in healthy controls' plasma. In gastric cancer cell lines, knock-down of MEF2C-AS1 or FENDRR reduced the protein levels of FAT3, NTN1 and LYVE1 (the co-expressed genes), which were related with gastric cancer cell proliferation and invasion by previous studies. In addition, knock-down of MEF2C-AS1 or FENDRR promoted aggressive tumor behaviors in in-vitro assays. In this study, we provide a valuable resource of lncRNAs which might play important roles in the function of oncogenes or tumor suppressors affecting the development and progression of diffuse gastric cancer.

The novel long noncoding RNA RP11-357H14.17 acts as an oncogene by promoting cell proliferation and invasion in diffuse-type gastric cancer.

Current evidence indicates that long noncoding RNAs (lncRNAs) play pivotal roles in human cancers. The present study aims to assess differentially expressed lncRNAs related to diffuse-type gastric carcinoma (DGC). Next-generation RNA sequencing was carried out to detect aberrantly expressed lncRNAs in DGC. Real-time polymerase chain reaction (RT-PCR) was performed to evaluate RP11-357H14.17 gene expression levels in DGC cell lines/tissues comparatively with normal gastric epithelial cell lines and adjacent normal tissues. The associations of RP11-357H14.17 expression levels with the clinicopathological features were also analyzed. The regulatory effects of RP11-357H14.17 on the biological behaviors of DGC cells were evaluated by MTT, colony formation assays, flow cytometry for apoptosis, wound healing assay, and transwell migration and invasion assays. RP11-357H14.17 expression was remarkably increased in DGC tissues and cell lines compared with normal gastric epithelial cells and adjacent normal tissues. High levels of RP11-357H14.17 were associated with increased tumor size, deeper depth of invasion, lymphatic metastasis, and advanced pathological stage. Further experiments demonstrated that the DGC cells MGC-803 transfected with si-RP11-357H14.17 showed reduced cell proliferation, migration, invasion, enhanced G1 phase arrest and cell apoptosis. These findings suggest that the novel lncRNA RP11-357H14.17 is associated with poor prognosis, and may serve as a potential prognostic biomarker and target for new antineoplastic therapies in human DGC.

TSPAN1 functions as an oncogene in gastric cancer and is downregulated by miR-573.

Tetraspanin 1 (TSPAN1) has been reported to be upregulated in gastric cancer (GC). However, whilst TSPAN1 is positively correlated with clinical stage and negatively correlated with survival rates, its function in GC remains elusive. Here we show that expression of TSPAN1 is significantly higher in GC tissues compared to non-cancerous tissues. Furthermore, we demonstrate that RNAi-mediated down-regulation of TSPAN1 expression markedly blocks GC cell proliferation, cell cycle progression and invasive activity. We identified TSPAN1 as a novel target gene of miR-573. Overexpression of miR-573 suppressed proliferation and invasion of GC cells by down-regulation of TSPAN1 expression. Restoration of TSPAN1 rescued the effects of miR-573 overexpression. Therefore, our findings suggest that the miR-573/TSPAN1 axis is important in the control of gastric carcinogenesis.

Caveolin-1 is a modulator of fibroblast activation and a potential biomarker for gastric cancer.

Stromal fibroblasts play an important role in chronic cancer-related inflammation and the development as well as progression of malignant diseases. However, the difference and relationship between inflammation-associated fibroblasts (IAFs) and cancer-associated fibroblasts (CAFs) are poorly understood. In this study, gastric cancer-associated fibroblasts (GCAFs) and their corresponding inflammation-associated fibroblasts (GIAFs) were isolated from gastric cancer (GC) with chronic gastritis and cultured in vitro. These activated fibroblasts exhibited distinct secretion and tumor-promoting behaviors in vitro. Using proteomics and bioinformatics techniques, caveolin-1 (Cav-1) was identified as a major network-centric protein of a sub-network consisting of 121 differentially expressed proteins between GIAFs and GCAFs. Furthermore, immunohistochemistry in a GC cohort showed significant difference in Cav-1 expression score between GIAFs and GCAFs and among patients with different grades of chronic gastritis. Moreover, silencing of Cav-1 in GIAFs and GCAFs using small interfering RNA increased the production of pro-inflammatory and tumor-enhancing cytokines and chemokines in conditioned mediums that elevated cell proliferation and migration when added to GC cell lines AGS and MKN45 in vitro. In addition, Cav-1 status in GIAFs and GCAFs independently predicted the prognosis of GC. Our findings indicate that Cav-1 loss contributes to the distinct activation statuses of fibroblasts in GC microenvironment and gastritis mucosa, and Cav-1 expression in both GCAFs and GIAFs may serve as a potential biomarker for GC progression.

Experimental study on sustained-release 5-Fluorouracil implantation in canine peritoneum and para-aortic abdominalis.

OBJECTIVE: To observe local and systemic toxicity after sustained-release 5-fluorouracil (5-Fu) implantation in canine peritoneum and para-aortic abdominalis and the changes of drug concentration in the local implanted tissue with time. METHODS: 300 mg sustained-release 5-Fu was implanted into canine peritoneum and para-aorta abdominalis. Samples were taken 3, 5, 7 and 10 days after implantation for assessment of changes and systemic reactions. High performance liquid chromatography was applied to detect the drug concentrations of peritoneal tissue at different distances from the implanted site, lymphatic tissue of para-aortic abdominalis, peripheral blood and portal venous blood. RESULTS: 10 days after implantation, the drug concentrations in the peritoneum, lymphatic tissue and portal vein remained relatively high within 5 cm of the implanted site. There appeared inflammatory reaction in the local implanted tissue, but no visible pathological changes such as cell degeneration and necrosis, and systemic reaction like anorexia, nausea, vomiting and fever. CONCLUSIONS: Sustained-release 5-Fu implantation in canine peritoneum and para-aortic abdominalis can maintain a relatively high tumour- inhibiting concentration for a longer time in the local implanted area and portal vein, and has mild local and systemic reactions. Besides, it is safe and effective to prevent or treat recurrence of gastrointestinal tumours and liver metastasis.

Long non-coding RNA GHET1 promotes gastric carcinoma cell proliferation by increasing c-Myc mRNA stability.

Long non-coding RNAs (lncRNAs), a recently characterized class of non-coding RNAs, have been shown to have important regulatory roles and are de-regulated in a variety of tumors. However, the contributions of lncRNAs to gastric carcinoma and their functional mechanisms remain largely unknown. In this study, we found that lncRNA gastric carcinoma high expressed transcript 1 (lncRNA-GHET1) was up-regulated in gastric carcinoma. The over-expression of this lncRNA correlates with tumor size, tumor invasion and poor survival. Gain-of-function and loss-of-function analyses demonstrated that GHET1 over-expression promotes the proliferation of gastric carcinoma cells in vitro and in vivo. Knockdown of GHET1 inhibits the proliferation of gastric carcinoma cells. RNA pull-down and immunoprecipitation assays confirmed that GHET1 physically associates with insulin-like growth factor 2 mRNA binding protein 1 (IGF2BP1) and enhances the physical interaction between c-Myc mRNA and IGF2BP1, consequently increasing the stability of c-Myc mRNA and expression. The expression of GHET1 and c-Myc is strongly correlated in gastric carcinoma tissues. Depletion of c-Myc abolishes the effects of GHET1 on proliferation of gastric carcinoma cells. Taken together, these findings indicate that GHET1 plays a pivotal role in gastric carcinoma cell proliferation via increasing c-Myc mRNA stability and expression, which suggests potential use of GHET1 for the prognosis and treatment of gastric carcinoma.

Influence of ERCC1 and ERCC4 polymorphisms on response to prognosis in gastric cancer treated with FOLFOX-based chemotherapy.

Polymorphisms in the excision repair cross-complimentary group 1 (ERCC1)-excision repair cross-complimentary group 4 (ERCC4) genes have been implicated in the prognosis of various cancers. We conducted a cohort study to investigate the role of ERCC1-ERCC4 gene polymorphisms on the response to chemotherapy and the role of these two gene polymorphisms on the clinical outcomes of gastric cancer. Four hundred forty-seven patients with newly diagnosed and histopathologically confirmed primary gastric cancer were collected in our study and were followed up until March 2012. ERCC1 (rs11615, rs3212986C>A, and rs2298881) and ERCC4 (rs226466C>G, rs2276465, and rs6498486) were selected and genotyped. The overall chemotherapy response rate for treatment was 68 %. Carriers of the rs11615 TT and T allele and ERCC1 rs2298881 CC and C allele had a marginally significantly higher response rate to the chemotherapy. In the Cox proportional hazard model, the hazard ratios (HRs) for overall survival (OS) in patients carrying ERCC1 rs11615 TT genotype and T allele were 0.53 (0.29-0.95) and 0.63 (0.42-0.94), respectively. Similarly, we found a significant decreased risk of death from gastric cancer among patients carrying ERCC1 rs2298881 CC genotype and C allele when compared with CC genotype, and HRs (95% confidence interval (CI)) of OS were 0.50 (0.24-0.98) and 0.62 (0.40-0.96), respectively. Moreover, individuals carrying ERCC1 rs11615 T allele and rs2298881 C allele could decrease a 0.62-fold risk of death from gastric cancer. This study reported a carriage of ERCC1 rs11615, and rs2298881 polymorphism can be used as a predictor of response to folinic acid/5-fluorouracil (5-FU)/oxaliplatin (FOLFOX)-based chemotherapy in gastric cancer patients.

Genetic polymorphisms of XRCC1 gene and susceptibility to gastric cancer in Chinese Han population.

This study aims to evaluate whether the c.1471G > A and c.1686C > G genetic polymorphisms of XRCC1 gene influencing gastric cancer susceptibility. A total of 813 subjects with Chinese Han ethnicity were enrolled. Our data suggest that the allele and genotype frequencies are significantly different from gastric cancer patients with cancer-free controls. We find that c.1471G > A and c.1686C > G genetic polymorphisms statistically increase the risk of gastric cancer. Our findings indicate these two genetic polymorphisms are related with the susceptibility to gastric cancer, and could be used as molecular markers for detecting gastric cancer in Chinese Han ethnicity.

Long noncoding RNA CCAT1, which could be activated by c-Myc, promotes the progression of gastric carcinoma.

PURPOSE: Long noncoding RNAs (lncRNAs) have been shown to have functional roles in cancer biology and are deregulated in many tumors. The specific aim of this study was to determine the role of a long noncoding RNA CCAT1 in the progression of gastric carcinoma and discover which factors contribute to the deregulation of CCAT1. METHODS: A computational screen of CCAT1 promoter was conducted to search for transcription-factor-binding sites. The association of c-Myc with the CCAT1 promoter in vivo was tested by chromatin immunoprecipitation assay. CCAT1 promoter activities were examined by luciferase reporter assay. The function of the c-Myc binding site in the CCAT1 promoter region was tested by a promoter assay with nucleotide substitutions in the putative E-box. The effect of CCAT1 on gastric carcinoma cell proliferation and migration was tested using in vitro cell proliferation and migration assays. RESULTS: CCAT1 levels were markedly increased in gastric carcinoma tissues compared with normal tissues. c-Myc directly binds to the E-box element in the promoter region of CCAT1, and when ectopically expressed increased promoter activity and expression of CCAT1. Nucleotide substitutions in the E-box element in the promoter region abrogated c-Myc-dependent promoter activation. The expression of CCAT1 and c-Myc shows strong association in gastric carcinomas. Moreover, abnormally expressed CCAT1 promotes cell proliferation and migration. CONCLUSIONS: These data suggest that c-Myc induction of CCAT1 holds an important role in gastric carcinoma and implicate the potential application of CCAT1 in the treatment of gastric carcinoma.