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Background: The initiation time and formula for supplemental parenteral nutrition after surgery require optimization, especially in older patients undergoing major gastrointestinal surgery. This study aimed to assess the effect of early supplementation with a branched-chain amino acid (BCAA)-enriched formula (BAF) on short-term postoperative outcomes in older patients undergoing gastric surgery., Methods: This single-center, prospective, double-blinded, randomized clinical trial was conducted from March 10, 2020, to September 15, 2022. Patients aged 65-80 years with gastric cancer scheduled for curative resection were assessed for eligibility and randomly allocated to a high-proportion BCAA (HBCAA) (early supplementation with the BAF) or control (routine nutrition) group. The primary outcome was the standardized length of hospital stay (LOS)., Results: A total of 150 patients were randomized. Thirteen patients were excluded due to the resection of other organs, presence of metastasis, or withdrawal of consent. Finally, we included 70 and 67 patients in the HBCAA and control groups, respectively (mean age: 70.5 ± 4.2 years; 96 men [70.1%]). The standardized LOS was significantly shorter in the treatment group than in the control group (median [interquartile range]: 8.0 [7.8, 8.0] vs. 8.5 [8.0, 9.0] days; mean difference, 0.38; 95% confidence interval [CI], 0.02-0.74 days; P < .001). Patients in the HBCAA group showed better gastrointestinal function with faster defecation (4.0 [3.6, 5.0] vs. 5.0 [4.0, 5.5] days; mean difference, 0.6 days; 95% CI, 0.26-0.94 days; P < .001) and semi-liquid diet initiation (8.0 [7.5, 8.0] vs. 8.0 [8.0, 8.8] days; mean difference, 0.36 days; 95% CI, 0.03-0.7 days; P < .001) and had lesser weight loss at postoperative day 5 than those in the control group did (3.5 [2.7, 6.5] vs. 4.9 [3.3, 7.6]%; mean difference, 1.23%; 95% CI, 0.27-2.19%; P = .011)., Conclusions: In this randomized clinical trial, compared with routine nutrition, early supplementation with a BAF was associated with a shorter standardized LOS in older patients undergoing gastric surgery, suggesting that it may be a favorable strategy for patients with a poor tolerance to external nutrition who are undergoing major surgery., Trial Registration: ClinicalTrials.gov; Identifier: ChiCTR2000029635., (© 2024. The Author(s).)

Tumor imaging represents an ideal environment for collecting novel biomarkers from different technologies, as patients with tumors often undergo multiple imaging studies.With the aging of the Chinese population, the number of elderly patients with gastric cancer is also increasing. In the past, patients with gastric cancer in the elderly have been conservative in whether surgical treatment can be performed, and advanced age is regarded as a relative contraindication to the effect of surgical treatment on gastric cancer patients. To investigate the clinical characteristics of patients with upper gastrointestinal hemorrhage complicated by deep vein thrombosis in elderly patients with gastric cancer. One patient with upper gastrointestinal hemorrhage complicated by deep venous thrombosis, and elderly gastric cancer patients admitted to our hospital on 11 October 2020, were selected. After anti-shock symptomatic support, filter placement, prevention and treatment of thrombosis, gastric cancer eradication, anticoagulation, immune regulation, etc. Treatment and long-term follow-up observation. Long-term follow-up showed that the patient's condition was stable, there was no sign of metastasis or recurrence after radical gastrectomy for gastric cancer, and there were no serious pre- and post-operative complications such as upper gastrointestinal bleeding and deep vein thrombosis, and the prognosis was satisfactory. How to choose the appropriate operation timing and method for elderly gastric cancer patients with upper gastrointestinal bleeding and deep vein thrombosis at the same time to maximize benefits, clinical experience in this area is particularly valuable.

New biomarkers for early diagnosis of gastric cancer (GC), the second leading cause of cancer-related death, are urgently needed. IGFBP7, known to play various roles in multiple tumours, is complexly regulated across diverse cancer types, as evidenced by our pancancer analysis. Bioinformatics analysis revealed that IGFBP7 expression was related to patient prognosis, tumour clinicopathological characteristics, tumour stemness, microsatellite instability and immune cell infiltration, as well as the expression of oncogenes and immune checkpoints. GSEA links IGFBP7 to several cancer-related pathways. IGFBP7 deficiency inhibited GC cell proliferation and migration in vitro. Furthermore, an in vivo nude mouse model revealed that IGFBP7 downregulation suppressed the tumorigenesis of GC cells. Western blotting analysis showed that the JAK1/2-specific inhibitor ruxolitinib could rescue alterations induced by IGFBP7 overexpression in GC cells. Additionally, our bioinformatics analysis and in vitro assays suggested that IGFBP7 is regulated by DNA methylation at the genetic level and that the RNA m 6 A demethylase FTO modulates it at the posttranscriptional level. This study emphasizes the clinical relevance of IGFBP7 in GC and its influence on cell proliferation and migration via the JAK/STAT signalling pathway. This study also highlights the regulation of IGFBP7 in GC by DNA and m 6 A RNA methylation., (© 2024 The Author(s). Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Background: Alpha-fetoprotein elevated gastric cancer (AFPGC) got growing interests for its aggressive nature and unfavorable prognosis. Here, a phase 1 dose escalation study was conducted to evaluate safety and efficacy of zimberelimab (GLS-010, anti-PD-1) plus lenvatinib and chemotherapy (XELOX) as the first-line treatment for AFPGC., Methods: Histologically confirmed HER2-negative, advanced GC patients with elevated serum AFP level (≥ 20 ng/ml) were screened. Using a 3 + 3 dose escalation design, patients were administered varying doses of lenvatinib (12, 16, 20 mg) with GLS-010 and XELOX. The primary endpoints were safety and determination of recommended phase II dose (RP2D). Secondary endpoints included overall response rate (ORR), progression-free survival (PFS) and disease control rate., Results: Nine patients were enrolled with no dose-limiting toxicities observed. Most frequent treatment-related AEs were fatigue (55.6%), hand-foot syndrome (55.6%) and rash (55.6%), and no grade ≥ 4 AEs were reported. All patients exhibited disease control with ORR reaching 33.3%. The median PFS and OS reached 7.67 months (95% CI 4.07-11.27) and 13.17 months (95% CI 2.78-23.56), respectively. Serum AFP level was found correlated with therapeutic responses. Further 16s rRNA sequencing analysis demonstrated altered gut microbiota with elevated abundance of Lachnospiraceae bacterium-GAM79 and Roseburia hominis A2-183., Conclusions: GLS-010 plus lenvatinib and XELOX demonstrated a manageable safety profile with promising efficacy for AFPGC. With RP2D of lenvatinib determined as 16 mg, further expansion cohort is now ongoing. Translational investigation suggested that serum AFP can be indictive for therapeutic responses and certain microbiota species indicating favorable responses to immunotherapy was elevated after the combinational treatment., (© 2024. The Author(s).)

Objective: To investigate the prognostic value of death-associated protein 5 (DAP5) in gastric cancer (GC) and its regulatory effect on aerobic glycolysis in GC cells., Methods: We analyzed DAP5 expression levels in GC and adjacent tissues and its association with survival outcomes of GC patients using public databases. We collected paired samples of GC and adjacent tissues from 102 patients undergoing radical resection of GC in our hospital from June, 2012 to July, 2017, and analyzed the correlation of DAP5 expression level detected immunohistochemically with the clinicopathological parameters of the patients. Cox regression analysis, Kaplan-Meier analysis, and ROC curves were used to explore the independent risk factors and the predictive value of DAP5 expression for 5-year survival of the patients. In the cell experiments, we observed the changes in aerobic glycolysis in MGC-803 cells following lentivirus-mediated DAP5 knockdown or overexpression by measuring glucose uptake and cellular lactate level and using qRT-PCR and Western blotting., Results: Analysis using the public databases showed that DAP5 was highly expressed in GC and correlated with tumor progression and poor survival outcomes of the patients ( P < 0.05). In the clinical samples, DAP5 expression was significantly higher in GC than in the adjacent tissues (3.19±0.60 vs 1.00±0.12; t =36.863, P < 0.01), and a high expression of DAP5 was associated with a reduced 5-year survival rate of the patients (17.6% vs 72.5%; χ 2 =29.921, P < 0.05). A high DAP5 expression, T3-4, N2-3, and CEA≥5 ng/mL were identified as independent risk factors affecting 5-year survival outcomes of GC ( P < 0.05), for which DAP5 expression showed a prediction sensitivity, specificity and accuracy of 73.2%, 80.4% and 79.0%, respectively. In MGC-803 cells, DAP5 knockdown significantly reduced glucose uptake, lactate level and the expressions of GLUT1, HK2 and LDHA, and DAP5 overexpression produced the opposite effects ( P < 0.05)., Conclusion: A high expression of DAP5 in GC, which enhances cellular aerobic glycolysis to promote cancer progression, is correlated with a poor survival outcome and may serve as a biomarker for evaluating long-term prognosis of GC patients.

Background: The prognosis of patients with previously treated advanced gastric or gastroesophageal junction (GEJ) cancer remains poor. Given the robust development of immunotherapy and targeted therapy during the last decades, we aimed to investigate if the combination of traditional second-line chemotherapy with sintilimab and apatinib could bring survival benefits for these patients., Methods: In this single-center, single-arm, phase II trial, patients with previously treated advanced gastric or GEJ adenocarcinoma received specific dose level of intravenous paclitaxel or irinotecan (investigator's choice), 200 mg intravenous sintilimab on day 1, and 250 mg oral apatinib once daily continuously in each cycle until disease progression, intolerable toxicity, or withdrawal of consent. The primary endpoints were objective response rate and progression-free survival. The secondary endpoints were mainly overall survival and safety., Results: From May 2019 to May 2021, 30 patients were enrolled. At the data cutoff date (March 19, 2022), the median follow-up duration was 12.3 months and 53.6% (95% CI, 33.9-72.5%) patients achieved objective response. The median progression-free survival and overall survival were 8.5 months (95% CI, 5.4-11.5) and 12.5 months (95% CI, 3.7-21.3), respectively. Grade 3-4 adverse events included hematological toxicities, elevated alanine aminotransferase, elevated aspartate aminotransferase, elevated alkaline phosphatase, elevated gamma-glutamyl transpeptidase, hyperbilirubinemia and proteinuria. The most frequent grade 3-4 adverse event was neutropenia (13.3%). No serious treatment-related adverse events or treatment-related deaths occurred., Conclusion: Sintilimab plus apatinib and chemotherapy demonstrates promising anti-tumor activity with manageable safety profile in patients with previously treated advanced gastric or GEJ cancer., Trial Registration: ClinicalTrials.gov: NCT05025033, 27/08/2021., (© 2023. The Author(s).)

Diffuse-type gastric cancer (DGC) and intestinal-type gastric cancer (IGC) are the major histological types of gastric cancer (GC). The molecular mechanism underlying DGC and IGC differences are poorly understood. In this research, we carry out multilevel proteomic analyses, including proteome, phospho-proteome, and transcription factor (TF) activity profiles, of 196 cases covering DGC and IGC in Chinese patients. Integrative proteogenomic analysis reveals ARIDIA mutation associated with opposite prognostic effects between DGC and IGC, via diverse influences on their corresponding proteomes. Systematical comparison and consensus clustering analysis identify three subtypes of DGC and IGC, respectively, based on distinct patterns of the cell cycle, extracellular matrix organization, and immune response-related proteins expression. TF activity-based subtypes demonstrate that the disease progressions of DGC and IGC were regulated by SWI/SNF and NFKB complexes. Furthermore, inferred immune cell infiltration and immune clustering show Th1/Th2 ratio is an indicator for immunotherapeutic effectiveness, which is validated in an independent GC anti-PD1 therapeutic patient group. Our multilevel proteomic analyses enable a more comprehensive understanding of GC and can further advance the precision medicine., (© 2023. The Author(s).)

Circulating tumour DNA (ctDNA) has emerged as an ideal biomarker for the early diagnosis and prognosis of gastric cancer (GC). In this work, a pump-free, high-throughput microfluidic chip coupled with catalytic hairpin assembly (CHA) and hybridization chain reaction (HCR) as the signal cascade amplification strategy (CHA-HCR) was developed for surface-enhanced Raman scattering (SERS) assays of PIK3CA E542K and TP53 (two GC-related ctDNAs). The chip consisted of six parallel functional units, enabling the simultaneous analysis of multiple samples. The pump-free design and hydrophilic treatment with polyethylene glycol (PEG) realized the automatic flow of reaction solutions in microchannels, eliminating the dependence on external heavy-duty pumps and significantly improving portability. In the reaction region of the chip, products generated by target-triggered CHA initiated the HCR, forming long nicked double-stranded DNA (dsDNA) on the Au nanobowl (AuNB) array surface, to which numerous SERS probes (Raman reporters and hairpin DNA-modified Cu 2 O octahedra) were attached. This CHA-HCR strategy generated numerous active "hot spots" around the Cu 2 O octahedra and AuNB surface, significantly enhancing the SERS signal intensity. Using this chip, an ultralow limit of detection (LOD) for PIK3CA E542K (1.26 aM) and TP53 (2.04 aM) was achieved, and the whole process was completed within 13 min. Finally, a tumour-bearing mouse model was established, and ctDNA levels in mouse serum at different stages were determined. To verify the experimental accuracy, the gold-standard qRT-PCR assay was utilized, and the results showed a high degree of consistency. Thus, this rapid, sensitive and cost-effective SERS microfluidic chip has potential as an ideal detection platform for ctDNA monitoring., (© 2022. The Author(s).)

Despite success in hematologic malignancies, the treatment landscape of chimeric antigen receptor (CAR) T cell therapy for solid tumors remains limited. Claudin18.2 (CLDN18.2)-redirected CAR T cells showed promising efficacy against gastric cancer (GC) in a preclinical study. Here we report the interim analysis results of an ongoing, open-label, single-arm, phase 1 clinical trial of CLDN18.2-targeted CAR T cells (CT041) in patients with previously treated, CLDN18.2-positive digestive system cancers ( NCT03874897 ). The primary objective was safety after CT041 infusion; secondary objectives included CT041 efficacy, pharmacokinetics and immunogenicity. We treated 37 patients with one of three CT041 doses: 2.5 × 10 8 , 3.75 × 10 8 or 5.0 × 10 8 cells. All patients experienced a grade 3 or higher hematologic toxicity. Grade 1 or 2 cytokine release syndrome (CRS) occurred in 94.6% of patients. No grade 3 or higher CRS or neurotoxicities, treatment-related deaths or dose-limiting toxicities were reported. The overall response rate (ORR) and disease control rate (DCR) reached 48.6% and 73.0%, respectively. The 6-month duration of response rate was 44.8%. In patients with GC, the ORR and DCR reached 57.1% and 75.0%, respectively, and the 6-month overall survival rate was 81.2%. These initial results suggest that CT041 has promising efficacy with an acceptable safety profile in patients with heavily pretreated, CLDN18.2-positive digestive system cancers, particularly in those with GC., (© 2022. The Author(s).)

Objective: To investigate the expression of aldehyde dehydrogenase 3B1 (ALDH3B1) in gastric cancer and explore its correlation with the pathological parameters and long-term prognosis of the patients., Methods: We analyzed the clinical data of 101 patients who underwent radical gastrectomy for gastric cancer in our hospital between January, 2013 and November, 2016, and examined the expression of ALDH3B1 in paraffin-embedded samples of gastric cancer tissues and adjacent tissues from these cases by immunohistochemical staining. We evaluated the correlation between ALDH3B1 expressions and histopathological parameters and assessed the predictive value of ALDH3B1 expression for long-term survival of the patients. We also examined the effect of lentivirus-mediated interference and overexpression of ALDH3B1 on the malignant behaviors of MGC-803 gastric cancer cells., Results: The expressions of ALDH3B1 and Ki67 were significantly higher in gastric cancer tissues than in adjacent tissues ( P < 0.05). In gastric cancer patients, ALDH3B1 expression was positively correlated with peripheral blood CEA and CA19-9 levels ( P < 0.01). The proportion of patients with CEA ≥5 μg/L, CA19-9 ≥37 kU/L, T stage of 3- 4, and N stage of 2-3 was significantly greater in high ALDH3B1 expression group than in low expression group. Kaplan-Meier survival analysis showed that the 5-year survival rate was significantly lower in gastric cancer patients with high ALDH3B1 expressions ( P < 0.01). Univariate and Cox multiple regression analyses identified a high expression of ALDH3B1 ( P < 0.05, HR= 0.231, 95% CI : 0.064-0.826), CEA≥5 μg/L ( P < 0.01, HR=4.478, 95% CI : 1.530-13.110), CA19-9≥37 kU/L ( P < 0.01, HR=3.877, 95% CI : 1.625-9.247), T stage of 3-4 ( P < 0.01, HR=4.953, 95% CI : 1.768-13.880), and N stage of 2-3 ( P < 0.05, HR=2.152, 95% CI : 1.152-4.022) as independent risk factors affecting 5-year survival after radical gastrectomy. The relative ALDH3B1 expression level, at the cut-off point of 4.66, showed a sensitivity of 76.47% and a specificity of 76% for predicting 5-year postoperative death ( P < 0.01). In the cell experiment, overexpression of ALDH3B1 obviously promoted the proliferation, migration and invasion of MGC-803 cells., Conclusion: As an independent risk factor affecting 5-year survival after radical gastrectomy, ALDH3B1 is highly expressed in gastric cancer and correlated with pathological parameters of the tumor, and a high ALDH3B1 expression may promote proliferation, invasion and metastasis of gastric cancer cells.

Gastric cancer (GC) is the fifth leading cause of cancer-related death worldwide and is accompanied by low diagnosis and survival rates. The molecular mechanism of GC must be elucidated to improve treatment strategies. Recent research has shown that the expression of myelin and lymphocyte (MAL) protein is reduced in a variety of adenocarcinomas and has the function of suppressing tumor growth. However, the mechanism by which MAL regulates the epithelial-mesenchymal transition (EMT) in GC remains unclear. Here, we showed that MAL expression was downregulated in specimens from patients with GC and was negatively correlated with the clinical stage. Gain- and loss-of function assays showed that interference with MAL significantly increased tumor cell proliferation, metastasis, invasion and the EMT. Overexpression of MAL significantly inhibited the malignant behavior of GC cells. Moreover, MAL suppressed the malignant behavior of GC cells by inhibiting STAT3 phosphorylation in vitro and in vivo. Our data indicate that MAL suppresses the malignant behavior of GC cells via the STAT3/EMT axis. This study also provides insights into the pathophysiological process of GC and a reference for diagnosis and treatment., (© 2022. The Author(s).)

RhoA is a member of the RHO family GTPases and is associated with essential functions in gastric cancer. In this study, we identified a gastric cancer biomarker, termed the "regulation of RhoA activity panel" (RRAP). Patients with gastric cancer from The Cancer Genome Atlas database were divided into training (N=160) and validation (N=155) cohorts. A cohort of 109 Chinese gastric cancer patients was utilized as an independent validation. Patients with mutated RRAP showed significantly better overall survival than patients with wild type RRAP. We also analyzed the association between RRAP and the migration capacity, immune-related signatures, and the tumor microenvironment. RRAP-mutant tumors had a significantly lower degree of lymph node metastasis and lower activities of migration-related pathways. These tumors also showed significantly increased immune cell infiltration and cytotoxic activity. Furthermore, two independent patient cohorts who received immune checkpoint blockade therapy were assessed for RRAP mutant status. As expected, for both immunotherapy cohorts, higher response rates to immune checkpoint blockade therapy were observed in patients with RRAP-mutant tumors than in patients with wild type RRAP tumors. Overall, this study indicates that the RRAP gene set is a potential biomarker for gastric cancer prognosis and therapeutic selection.

Background Gastric malignancy is the third most frequently encountered cancer globally and have been documented to confer extremely poor prognosis, given their limited treatment options. The up-regulation of hepatocyte growth factor (HGF) has been found in various tumor tissues, including GC tissue, and has been linked with tumor development. Nevertheless, the pathways leading to HGF upregulation have yet to be fully explored. Methods Immunohistochemistry (IHC) assay was used to detect HGF expression in human gastric tumor tissues, while western blotting allowed quantification of protein levels. Bioinformatics tools were used to predict potential miRNA that may target HGF mRNA. Relative levels of miR-15a/16/195 as well as the target mRNA levels were analyzed with qRT-PCR. Direct targeting between miRNA and mRNA was then validated by luciferase assay. Finally, a mouse xenograft tumor model was selected to demonstrate the in vivo effects of miR-15a/16/195. Results HGF protein expressions were markedly raised, while miR-15a/16/195 levels were dramatically down-regulated in tumor tissues of GC. miR-15a/16/195 were shown to directly bind with the 3'-UTR of HGF mRNA. This study demonstrated that HGF can be repressed by overexpressed miR-15a/16/195, which resulted in the suppression of GC cell proliferation and migration. Furthermore, in the xenograft mouse model, miR-15a/16/195 were also found to have a tumor growth suppression effect. Conclusions miR-15a/16/195 suppresses tumorigenesis by targeting HGF and may have a potential therapeutic application in the clinical treatment of GC.

Background: Ferroptosis is a novel mode of non-apoptotic cell death induced by build-up of toxic lipid peroxides (lipid-ROS) in an iron dependent manner. Cancer-associated fibroblasts (CAFs) support tumor progression and drug resistance by secreting various bioactive substances, including exosomes. Yet, the role of CAFs in regulating lipid metabolism as well as ferroptosis of cancer cells is still unexplored and remains enigmatic., Methods: Ferroptosis-related genes in gastric cancer (GC) were screened by using mass spectrum; exosomes were isolated by ultra-centrifugation and CAF secreted miRNAs were determined by RT-qPCR. Erastin was used to induce ferroptosis, and ferroptosis levels were evaluated by measuring lipid-ROS, cell viability and mitochondrial membrane potential., Results: Here, we provide clinical evidence to show that arachidonate lipoxygenase 15 (ALOX15) is closely related with lipid-ROS production in gastric cancer, and that exosome-miR-522 serves as a potential inhibitor of ALOX15. By using primary stromal cells and cancer cells, we prove that exosome-miR-522 is mainly derived from CAFs in tumor microenvironment. Moreover, heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1) was found to mediate miR-522 packing into exosomes, and ubiquitin-specific protease 7 (USP7) stabilizes hnRNPA1 through de-ubiquitination. Importantly, cisplatin and paclitaxel promote miR-522 secretion from CAFs by activating USP7/hnRNPA1 axis, leading to ALOX15 suppression and decreased lipid-ROS accumulation in cancer cells, and ultimately result in decreased chemo-sensitivity., Conclusions: The present study demonstrates that CAFs secrete exosomal miR-522 to inhibit ferroptosis in cancer cells by targeting ALOX15 and blocking lipid-ROS accumulation. The intercellular pathway, comprising USP7, hnRNPA1, exo-miR-522 and ALOX15, reveals new mechanism of acquired chemo-resistance in GC.

Objectives: Hepatoid adenocarcinoma of the stomach (HAS) is characterized by histological resemblance to hepatocellular carcinoma and a poor prognosis. The aim of this study is to elucidate the clinicopathological and molecular characteristics of HAS., Methods: Forty-two patients with HAS who received gastrectomy were enrolled in this study. Based on a panel of 483 cancer-related genes, targeted sequencing of 24 HAS and 22 clinical parameter-matched common gastric cancer (CGC) samples was performed. Prognostic factors for overall survival (OS) and disease-free survival (DFS) were analysed with the Kaplan-Meier method., Results: The most frequently mutated gene in both HAS and CGC was TP53, with a mutation rate of 30%. Additionally, CEBPA, RPTOR, WISP3, MARK1, and CD3EAP were identified as genes with high-frequency mutations in HAS (10-20%). Copy number gains (CNGs) at 20q11.21-13.12 occurred frequently in HAS, nearly 50% of HAS tumours harboured at least one gene with a CNG at 20q11.21-13.12. This CNG tended to be related to more adverse biobehaviour, including poorer differentiation, greater vascular and nerve invasion, and greater liver metastasis. Pathway enrichment analysis revealed that the HIF-1 signalling pathway and signalling pathways regulating stem cell pluripotency were specifically enriched in HAS. The survival analysis showed that a preoperative serum AFP level ≥ 500 ng/ml was significantly associated with poorer OS (p = 0.007) and tended to be associated with poorer DFS (p = 0.05)., Conclusion: CNGs at 20q11.21-13.12 happened frequently in HAS and tended to be related to more adverse biobehaviour. The preoperative serum AFP level was a sensitive prognostic biomarker for DFS and OS.

Transforming growth factor-beta (TGF-β) signaling pathway plays pivotal roles in various types of cancer. TGF-β receptor 2 (TGFβR2) contains a kinase domain that phosphorylates and activates the downstream of the TGF-β signaling pathway. Our previous microarray analysis revealed marked changes in miR-181a expression in gastric cancers, and the bioinformatics analysis suggested that miR-181a negatively regulated TGFβR2. In order to verify the effect of miR-181a on TGFβR2 and clarify the influence of miR-181a on the migration and proliferation of gastric cancer, studies in gastric cancer cell lines and xenograft mouse models were carried out. We found that a reduced expression of TGFβR2 and an increased expression miR-181a in gastric cancer tissues compared to adjacent noncancerous tissues. A luciferase reporter assay confirmed that TGFβR2 was a target of miR-181a. In addition, we found that miR-181a mimics, which increased the level of miR-181a, downregulated the expression of TGFβR2 in the gastric cancer cell line SGC-7901. Moreover, both the overexpression of miR-181a and the downregulation of TGFβR2 promoted the migration and proliferation of SGC-7901 cells. Conversely, SGC-7901 cell migration and proliferation were inhibited by the downregulation of miR-181a and the overexpression of TGFβR2. Furthermore, the increased expression of miR-181a and the decreased expression of TGFβR2 also enhanced the tumor growth in mice bearing gastric cancer. Our results herein indicated that miR-181a promoted the migration and proliferation of gastric cancer cells by downregulating TGFβR2 at the posttranscriptional level. The present study suggests that miR-181a is a novel negative regulator of TGFβR2 in the TGF-β signaling pathway and thus represents a potential new therapeutic target for gastric cancer.

Objective: To explore association of the expression levels of adenylate cyclase-associated protein 2 (CAP2) in gastric cancer tissues with the histopathology and long-term prognosis of the malignancy., Methods: This study was conducted among a total of 105 patients with gastric cancer undergoing radical gastrectomy in our hospital between January, 2010 and October, 2013. Immunohistochemistry was used to quantitatively assess the expression of CAP2 in gastric cancer tissues and the adjacent tissues. Based on the median relative expression level of CAP2 of 3.5, the patients were divided into low CAP2 expression group ( n =52) and high CAP2 expression group ( n =53). The Cox regression model was used to analyze the effect of CAP2 expression on the 5-year survival rate of the patients, and ROC curve analysis was used to assess the predictive value of CAP2 expression for the patients' long-term survival., Results: Immunohistochemical analysis showed that the expression levels of CAP2 ( P &lt; 0.01) and Ki67 ( P &lt; 0.01) were significantly higher in gastric cancer tissues than in the adjacent tissues, and the expression level of CAP2 was positively correlated with Ki67 ( P &lt; 0.01), peripheral blood CEA ( P &lt; 0.01) and CA19-9 ( P &lt; 0.01). The percentages of patients with CEA≥5 μg/L, CA19-9≥37 kU/L, pathological grade of G3-G4, T stage of 3-4, and N stage of 2-3 were significantly higher in patients with high CAP2 expression than in those with low CAP2 expression ( P &lt; 0.05). Kaplan- Meier survival analysis showed that the 5-year survival rate was significantly lower in patients with a high CAP2 expression ( P &lt; 0.01). A high expression level of CAP2, CEA≥5μg/L, CA19-9≥37 and pathological grades G3-G4 were all independent risk factors for shortened 5-year survival after radical gastrectomy ( P &lt; 0.01). With the relative expression level of 3.45 as the cut-off value, the sensitivity of CAP2 was 70.15% for predicting death 5 years after the surgery, with a specificity of 71.05% and an area under the curve of 0.779 ( P &lt; 0.01)., Conclusions: CAP2 is highly expressed in gastric cancer tissues in close relation with the tumor progression. CAP2 is an independent risk factor for 5-year survival rate after radical gastrectomy for gastric cancer and can be of clinical value in prognostic evaluation of the patients.

Background: As the most abundant epigenetic modification on mRNAs and long non-coding RNAs, N6-methyladenosine (m6A) modification extensively exists in mammalian cells. Controlled by writers (methyltransferases), readers (signal transducers), and erasers (demethylases), m6A influences mRNA structure, maturation, and stability, thus negatively regulating protein expression in a post-translational manner. Nevertheless, current understanding of m6A's roles in tumorigenesis, especially in gastric cancer (GC) remains to be unveiled. In this study, we assessed m6A's clinicopathological relevance to GC and explored the underlying mechanisms., Methods: By referring to a proteomics-based GC cohort we previously generated and the TCGA-GC cohort, we merged expressions of canonical m6A writers (METTL3/METTL14), readers (YTHDF1/YTHDF2/YTHDF3), and erasers (ALKBH5/FTO), respectively, as W, R, and E signatures to represent m6A modification. We stratified patients according to these signatures to decipher m6A's associations with crucial mutations, prognosis, and clinical indexes. m6A's biological functions in GC were predicted by gene set enrichment analysis (GSEA) and validated by in vitro experiments., Results: We discovered that W and R were potential tumor suppressive signatures, while E was a potential oncogenic signature in GC. According to W/R/E stratifications, patients with low m6A-indications were accompanied with higher mutations of specific genes (CDH1, AR, GLI3, SETBP1, RHOA, MUC6, and TP53) and also demonstrated adverse clinical outcomes. GSEA suggested that reduced m6A was correlated with oncogenic signaling and phenotypes. Through in vitro experiments, we proved that m6A suppression (represented by METTL14 knockdown) promoted GC cell proliferation and invasiveness through activating Wnt and PI3K-Akt signaling, while m6A elevation (represented by FTO knockdown) reversed these phenotypical and molecular changes. m6A may also be involved in interferon signaling and immune responses of GC., Conclusions: Our work demonstrated that low-m6A signatures predicted adverse clinicopathological features of GC, while the reduction of RNA m6A methylation activated oncogenic Wnt/PI3K-Akt signaling and promoted malignant phenotypes of GC cells., (© 2019 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

Dendrobium officinale is a herb in traditional Chinese medicine where D. officinale polysaccharides (DOP) are the main active ingredient. This study aimed at evaluating DOP efficiency at inhibiting 1-Methyl-2-nitro-1-nitrosoguanidine (MNNG) induced precancerous lesions of gastric cancer (PLGC) in rats through the Wnt/b-catenin pathway and analyzing the variations of serum endogenous metabolites. PLGC was established in male Sprague-Dawley (SD) rats by administering 150 μg/mL MNNG in drinking water for 7 months and giving 0.1 mL of 10% NaCl once weekly during the initial 20 weeks. Treatment with DOP inhibited the progress of PLGC through decreasing the expression of β-catenin by immunohistochemical analysis. The futher study indicated DOP downregulated gene expression of Wnt2β, Gsk3β, PCNA, CyclinD1, and β-catenin, as well as protein expression of Wnt2β, PCNA, and β-catenin. On the other hand, there were nine endogenous metabolites identified after the DOP treatment. Among these, the most significant one is betaine because of its strong antioxidant activity, leading to an anti-tumor effect. DOP can inhibit MNNG-induced PLGC models via regulating Wnt/β-catenin pathway and by changing endogenous metabolites.

Background: DNA aneuploidy has attracted growing interest in clinical practice. Nevertheless, its prognostic value in gastric cancer patients remains controversial. This meta-analysis aims to explore the impact of DNA ploidy status on the survival of gastric cancer patients., Methods: We used PubMed and Web of Science databases to retrieve relevant articles. The correlation between DNA aneuploidy and the clinicopathological features of gastric cancer, such as stage, depth of invasion (T), lymph node metastasis (N), distant metastasis (M), differentiation (G), tumor types (Lauren classification) and overall survival (OS) were evaluated. Hazard ratios (HRs) with corresponding 95% confidence intervals (CIs) were collected carefully from each article OS was presented with HRs. The relationships between DNA aneuploidy and each characteristic were analyzed using risk ratios (RR) and a 95% confidence interval (CI). Significance was established using P < 0.05. Funnel plot was conducted to detect the publication bias., Results: After careful selection, 25 studies involving 3449 cases were eligible for further analyses. Patients with DNA aneuploidy were considered at risk of more advanced stages (stage III-IV vs. stages I-II, RR = 1.23; 95% CI, 1.07 to 1.42; P = 0.003), lymph node metastasis (N+ vs. N-: RR = 1.43; 95% CI, 1.12 to 1.82, P = 0.004), and intestinal tumor type (intestinal vs. diffuse: RR = 1.45; 95% CI, 1.02 to 2.06; P = 0.04). And an adverse relation was observed between DNA aneuploidy and tumor differentiation. While no association was found between DNA aneuploidy and distant metastasis (P = 0.42) nor depth of tumor invasion (P = 0.86). Regarding overall survival, aneuploid tumors were associated with worse survival in all patients (P < 0.00001)., Conclusions: We found that DNA aneuploidy was an important predictor for gastric cancer patients, and should be used as a potential biomarker for further classification in gastric cancer.

γ-Tocotrienol (γ-T3) exhibits the activity of anticancer via regulating cell signaling pathways. Nuclear factor-κB (NF-κB), one of the crucial pro-inflammatory factors, is involved in the regulation of cell proliferation, apoptosis, invasion, and migration of tumor. In the present study, NF-κB activity inhibited by γ-T3 was investigated in gastric cancer cells. Cell proliferation, NF-κB activity, active protein phosphatase type 2A (PP2A), and ataxia-telangiectasia mutated (ATM) protein were explored using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT), methylene blue, enzyme-linked immunosorbent assay (ELISA), malachite green, luciferase, and Western blotting assays. The effects of γ-T3 on tumor growth and the expression of NF-κB and PP2A proteins were also further examined by implanting human gastric cancer cells in a BALB/c nude mouse model. The results showed that γ-T3 significantly inhibited the cell proliferation and attenuated the NF-κB activity in vitro and in vivo. γ-T3 dramatically increased PP2A activity and protein expression, which suppressed ATM phosphorylation and its translocation to the cytoplasm in gastric cancer cells. Thus, our findings may provide mechanistic insight into effects of γ-T3 on the regulation of NF-κB activity by a PP2A-dependent mechanism and suggest that PP2A may serve as a molecular target for a potential chemopreventive agent.

GC (gastric cancer) remains one of the most lethal malignancies worldwide. EGFR (epidermal growth factor receptor) plays an important role in the malignant process of GC, therefore, the present study addressed the relationship between EGFR and its potential regulators and examined their regulatory mechanisms in GC. We examined differences in the expression levels of EGFR in GC and adjacent non‑cancerous tissues. Bioinformatics analyses and dual luciferase reporter assays were used to confirm the putative relationship between miR‑138 or miR‑204 and EGFR, and their relationship was further detected using western blotting, RT‑PCR, and a series of cell studies. EGFR proteins were abundantly expressed in GC tissues, however EGFR mRNA levels remained indistinctive. Consequently, EGFR was revealed as a putative target of miR‑138 and miR‑204 which bound to the 3'UTR of EGFR mRNA. Further analysis revealed that miR‑138 and miR‑204 were significantly downregulated in GC tissues and the overexpression of miR‑138 and miR‑204 in GC cell lines resulted in the significant inhibition of EGFR protein levels and GC cell proliferation and metastasis. Rescue experiments confirmed that the roles of the two microRNAs were specific to EGFR. EGFR is a pivotal oncogene in GC progression that may be regulated by miR‑138 and miR‑204.

The diffuse-type gastric cancer (DGC) is a subtype of gastric cancer with the worst prognosis and few treatment options. Here we present a dataset from 84 DGC patients, composed of a proteome of 11,340 gene products and mutation information of 274 cancer driver genes covering paired tumor and nearby tissue. DGC can be classified into three subtypes (PX1-3) based on the altered proteome alone. PX1 and PX2 exhibit dysregulation in the cell cycle and PX2 features an additional EMT process; PX3 is enriched in immune response proteins, has the worst survival, and is insensitive to chemotherapy. Data analysis revealed four major vulnerabilities in DGC that may be targeted for treatment, and allowed the nomination of potential immunotherapy targets for DGC patients, particularly for those in PX3. This dataset provides a rich resource for information and knowledge mining toward altered signaling pathways in DGC and demonstrates the benefit of proteomic analysis in cancer molecular subtyping.

Chemoresistance is one of the causes of adverse effects in gastric cancer, including a poor response to cisplatin (DDP). Exosomes loaded with microRNA (miRNA), mRNA, and other non-coding RNAs could regulate drug resistance. Exo-anti-214 was extracted and verified. A Cell Counting Kit-8 (CCK-8) cell viability assay, flow cytometry, and transwell and immunofluorescence assays were performed to determine whether exo-anti-214 could sensitize cells to DDP in vitro. A combination of intravenously injected exo-anti-214 and intraperitoneal DDP was utilized in vivo. Additionally, potential targets of miR-214 were screened by mass spectrometry (MS) and confirmed via western blotting (WB). The levels of miR-214 in the human immortalized gastric epithelial cell line ges-1 and the human gastric adenocarcinoma cell lines SGC7901 and SGC7901/DDP gradually increased. Exo-anti-214 could fuse with cells and regulate potential targets, reducing cell viability, suppressing migration, and promoting apoptosis in vitro. Caudally injected exo-anti-214 was applied to reverse chemoresistance and repress tumor growth in vivo due to the downregulation of miR-214 and overexpression of possible target proteins in tumors. Exo-anti-214 could reverse the resistance to DDP in gastric cancer, which might serve as a potential alternative for the treatment of cisplatin-refractory gastric cancer in the future., (Copyright © 2018 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.)

Exosomes derived from cells have been found to mediate signal transduction between cells and to act as efficient carriers to deliver drugs and small RNA. Hepatocyte growth factor (HGF) is known to promote the growth of both cancer cells and vascular cells, and the HGF-cMET pathway is a potential clinical target. Here, we characterized the inhibitory effect of HGF siRNA on tumor growth and angiogenesis in gastric cancer. In addition, we showed that HGF siRNA packed in exosomes can be transported into cancer cells, where it dramatically downregulates HGF expression. A cell co-culture model was used to show that exosomes loaded with HGF siRNA suppress proliferation and migration of both cancer cells and vascular cells. Moreover, exosomes were able to transfer HGF siRNA in vivo, decreasing the growth rates of tumors and blood vessels. The results of our study demonstrate that exosomes have potential for use in targeted cancer therapy by delivering siRNA., (© 2018 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

Epidermal growth factor receptor (EGFR) plays an important role in various types of cancer. However, the therapeutic agents that target EGFR have not produced favorable results in gastric cancer. miRNAs are known to regulate gene expression at the post-transcriptional level. We wondered if miRNAs could be potential therapeutic agents for the targeted therapy against EGFR. In this study, we found an increase in the copies of EGFR mRNA and the upregulated expression of the EGFR protein in gastric cancer tissues compared with normal gastric tissues. Both bioinformatic analysis and luciferase reporter assay revealed that miR-455 could directly bind with the 3'-untranslated region (3'UTR) of EGFR mRNA. Subsequently, in vitro studies were conducted to identify the effects of miR-455 on cell proliferation and migration and further confirm the cancer-promoting role of EGFR in gastric cancer. The results revealed that miR-455 negatively regulated EGFR expression at the post-transcriptional level, thus suppressing cell growth and migration. To conclude, our results offer a potential targeted therapeutic method against EGFR in gastric cancer mediated by miR-455.

Epidermal growth factor receptor (EGFR) is known to be overexpressed in ~30% of gastric cancer (GC) cases, and may serve as an effective biomarker for predicting the clinical benefit of anti-EGFR therapy. However, the mechanism underlying the regulation of EGFR expression remains unknown. Evidence indicates that post-transcriptional regulation may exist in the process of EGFR expression. In the present study, we aimed to explore whether miR-370 is involved in this process, and how it impacts the biological behaviors of GC cells. In the present study, we first determined the role of EGFR in GC by means of an EGFR overexpression plasmid and siRNAs. Then, the expression levels of EGFR protein and mRNA in GC tissues were analyzed through immunohistochemistry and quantitative RT-PCR (RT-qPCR). Bioinformatics tools and dual-luciferase assay were applied to predict and validate the relevant miRNA targeting EGFR. Finally, human GC MGC-803 cells were selected to explore the effect of miRNA on cell proliferation and migration. We found that suppression of EGFR inhibited the proliferation and migration of GC cells. In addition, the levels of EGFR protein in the GC tissues were ~4 times higher than that in the corresponding paired non-cancerous tissues while the mRNA levels of EGFR were only ~2-fold as high as that in the adjacent non-cancerous tissues. Bioinformatics tools predicted that miRNA-370 was a regulator of EGFR and dual‑luciferase assay validated that miR-370 could directly bind to the 3'-untranslated region (3'-UTR) of EGFR mRNA. Meanwhile, an inverse correlation between miR-370 and EGFR was found in the GC tissues. Overexpression of miR-370 suppressed the proliferation and migration of GC cells, while downregulation of miR-370 promoted proliferation and migration. The present study may provide new information for understanding the molecular mechanism underlying the regulation of EGFR protein expression in GC and may be of important clinical significance to guide targeted therapy.

Gastric cancer is a common malignancy with limited treatment options and poor prognosis. Introduction of novel pathways of gastric cancer will provide candidates for target therapy. Hepatocyte growth factor activator inhibitor type 1 is an integral-membrane proteinase inhibitor. Hepatocyte growth factor activator inhibitor type 1 abnormality is found in various cancers and correlates with tumor progression and metastasis. However, the mechanisms underlying the dysregulation of hepatocyte growth factor activator inhibitor type 1 expression in gastric cancer remain unclear. Although microRNAs have been reported to be involved in the development of cancer, the roles of miR-221 and miR-222 in gastric cancer have not been reported yet. In this study, we showed that hepatocyte growth factor activator inhibitor type 1 protein was downregulated, while miR-221 and miR-222 were significantly increased in gastric cancer tissues. Bioinformatic predictions and luciferase assay verified that the 3'-untranslated region of the HAI-1 gene is a direct target site for miR-221 and miR-222. Overexpression of miR-221 and miR-222 in MGC-803 cells leads to the inhibition of hepatocyte growth factor activator inhibitor type 1 protein expression, thus promoting cell proliferation and migration; whereas knockdown of miR-221 and miR-222 showed opposite effects. Moreover, we found that the expression level of hepatocyte growth factor activator protein was increased when hepatocyte growth factor activator inhibitor type 1 was knocked down in MGC-803 cells. Thus, gastric cancer is probably an autocrine tumor, and the antitumor mechanism of hepatocyte growth factor activator inhibitor type 1 in vitro might be mediated by regulating the expression of hepatocyte growth factor activator protein. Therefore, our data illustrated a novel pathway comprising miR-221and miR-222 and hepatocyte growth factor activator inhibitor type 1 in gastric cancer, which is a potential target for future clinical use.

MicroRNAs (miRNAs) have been reported to be involved in each stage of tumor development in various types of cancers. We have previously showed that miR-16 is downregulated in cancer and acts as a tumor suppressor. Other studies indicated that hepatocyte growth factor (HGF)/c-Met is implicated in proliferation, migration, and other pathophysiological processes. However, little is known about the relationship between miR-16 and HGF/c-Met in gastric cancer (GC). In the present study, we used bioinformatics tools and related experiments to search for miRNAs targeting HGF. Here, we found that miR-16 suppressed HGF protein expression by directly targeting 3'-untranslated region (UTR) of HGF mRNA. Subsequently, it was illustrated the downregulation of miR-16 promotes, while overexpressed of miR-16 significantly inhibits cell proliferation and migration by negatively regulating HGF/c-Met pathway. Moreover, the biological role of HGF in GC cells was determined by using HGF siRNA and HGF-overexpressing plasmid, respectively. To conclude, our results provide a potential target by using miR-16 for the future clinical treatment of GC.

Systemic immune-inflammation index (SII), based on lymphocyte (L), neutrophil (N), and platelet (P) counts, was recently developed and reflects comprehensively the balance of host inflammatory and immune status. We explored its prognostic value in localized gastric cancer (GC) after R0 resection and the potential associations with Thymidine phosphorylase (TYMP), which was reported to increase the migration and invasion of gastric cancer cells. A total of 455 GC patients who received D2 gastrectomy were enrolled. Blood samples were obtained within 1 week before surgery to measure SII (SII = P × N/L). TYMP expression was measured on tumor sections by immunohistochemical analysis. Preoperative high SII indicated worse prognosis (HR: 1.799; 95% CI: 1.174-2.757; p = 0.007) in multivariate analysis and was associated with higher pathological TNM stage, deeper local invasion of tumor and lymph node metastasis (all p < 0.001). SII predicted poor overall survival in pathological TNM stage I subgroup also (p < 0.001). Furthermore we found that in high SII group, positive rate of TYMP expression increased (53.7% vs 42.7%, p = 0.046) and TYMP positive patients had higher SII score (median 405.9 vs. 351.9, p = 0.026). SII, as a noninvasive and low cost prognostic marker, may be helpful to identify higher-risk patients after R0 resection, even for stage I GC patients., Competing Interests: The authors declare no conflicts of interest.

UHRF1 is best known for its positive role in the maintenance of DNMT1-mediated DNA methylation and is implicated in a variety of tumor processes. In this paper, we provided evidence to demonstrate a role of UHRF2 in cell motility and invasion through the regulation of the epithelial-mesenchymal transition (EMT) process by acting as a transcriptional co-regulator of the EMT-transcription factors (TFs). We ectopically expressed UHRF2 in gastric cancer cell lines and performed multidimensional proteomics analyses. Proteome profiling analysis suggested a role of UHRF2 in repression of cell-cell adhesion; analysis of proteome-wide TF DNA binding activities revealed the up-regulation of many EMT-TFs in UHRF2-overexpressing cells. These data suggest that UHRF2 is a regulator of cell motility and the EMT program. Indeed, cell invasion experiments demonstrated that silencing of UHRF2 in aggressive cells impaired their abilities of migration and invasion in vitro Further ChIP-seq identified UHRF2 genomic binding motifs that coincide with several TF binding motifs including EMT-TFs, and the binding of UHRF2 to CDH1 promoter was validated by ChIP-qPCR. Moreover, the interactome analysis with IP-MS uncovered the interaction of UHRF2 with TFs including TCF7L2 and several protein complexes that regulate chromatin remodeling and histone modifications, suggesting that UHRF2 is a transcription co-regulator for TFs such as TCF7L2 to regulate the EMT process. Taken together, our study identified a role of UHRF2 in EMT and tumor metastasis and demonstrated an effective approach to obtain clues of UHRF2 function without prior knowledge through combining evidence from multidimensional proteomics analyses., (© 2016 by The American Society for Biochemistry and Molecular Biology, Inc.)

The aim of the present study was to investigate the clinical significance of microRNA-218 (miR-218) in gastric cancer. We enrolled 112 patients having undergone surgery for gastric cancer between May 2008 and June 2014. Expression of miR-218 was determined by real-time quantitative reverse transcription-polymerase chain reaction. Survival curves were plotted using the Kaplan-Meier method and compared by the log-rank test. We found that miR-218 expression was significantly downregulated in gastric cancer tissues compared to adjacent normal tissues (P < 0.001). Low miR-218 expression was significantly associated with tumor differentiation (P < 0.001), depth of tumor invasion (P = 0.006), and tumor node metastasis stage (P < 0.001). Kaplan-Meier survival analysis revealed that patients with low miR-218 levels showed significantly lower 5-year overall survival than those demonstrating high expression (P = 0.04). Multivariate Cox regression analyses indicated that low miR-218 expression constitutes an independent molecular biomarker for prediction of poor overall survival of gastric cancer patients (hazard ratio = 3.187, 95% confidence interval = 1.551-8.365, P = 0.037). In conclusion, miR-218 was remarkably downregulated in gastric cancer tissues and may serve as a prognostic biomarker for patients suffering from this disease.

Microvesicles (MVs) secreted from cells have been found to mediate signal transduction between cells. In the tumor microenvironment, VEGF released from cancer cells plays a key role in promoting tumor angiogenesis. In this study, we characterized the inhibitory effect of MV-delivered miR-29a/c on angiogenesis and tumor growth in gastric cancer (GC). We found that the downregulation of miR-29a/c increases VEGF expression and release in GC cells, promoting the growth of vascular cells. By simulating the tumor microenvironment, the MV-delivered miR-29a/c significantly suppresses VEGF expression in GC cells, inhibiting vascular cell growth, metastasis, and tube formation. We also used a tumor implantation mouse model to show that secreted MVs containing overexpressed miR-29a/c significantly reduced the growth rate of the vasculature and tumors in vivo. To conclude, our results contribute to a novel anti-cancer strategy using miRNA-containing MVs to control tumor cell growth by blocking angiogenesis., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

TGFBR2 serves as an initial regulator of the TGF-β signaling pathway, and loss or reduction of its expression leads to uncontrolled cell growth and invasion. TGFBR2 plays a crucial role in the carcinogenesis and malignant process of gastric cancer, but the mechanism remains unclear. In this study, we found that TGFBR2 protein levels were consistently upregulated in gastric cancer tissues, whereas TGFBR2 mRNA levels varied among these tissues, indicating that a post-transcriptional mechanism is involved in the regulation of TGFBR2. MiRNAs are known to regulate gene expression at the post-transcriptional level. Therefore, we performed bioinformatics analyses to search for miRNAs potentially targeting TGFBR2. MiR-17-5p was found to bind to the 3'UTR of TGFBR2 mRNA, and further validation of this specific binding was performed through a reporter assay. An inverse correlation between miR-17-5p and TGFBR2 protein was observed in gastric cancer tissues. Cell studies revealed that miR-17-5p negatively regulated TGFBR2 expression by directly binding to the 3'UTR of TGFBR2 mRNA, thereby promoting cell growth and migration. We also validated the role of TGFBR2 using siRNA and an overexpression plasmid. The results of our study suggest a novel regulatory network in gastric cancer mediated by miR-17-5p and TGFBR2 and may indicate that TGFBR2 could serve as a new therapeutic target in gastric cancer., Competing Interests: The authors declare that there is no conflict of interests regarding the publication of this article.

Gastric cancer is one of the most common malignant tumors worldwide; however, the efficacy of clinical treatment is limited. MicroRNAs (miRNAs) are a class of small non-coding RNAs that have been reported to play a key role in the development of cancer. They also provide novel candidates for targeted therapy. To date, in-depth studies on the molecular mechanisms of gastric cancer involving miRNAs are still absent. We previously reported that 5 miRNAs were identified as being significantly increased in gastric cancer, and the role of these miRNAs was investigated in the present study. By using bioinformatics tools, we found that more than 4,000 unique genes are potential downstream targets of gastric cancer miRNAs, and these targets belong to the protein class of nucleic acid binding, transcription factor, enzyme modulator, transferase and receptor. Pathway mapping showed that the targets of gastric cancer miRNAs are involved in the MAPK signaling pathway, pathways in cancer, the PI3K-Akt signaling pathway, the HTLV-1 signaling pathway and Ras signaling pathway, thus regulating cell growth, differentiation, apoptosis and metastasis. Analysis of the pathways related to miRNAs may provides potential drug targets for future therapy of gastric cancer.

Gastric cancer is one of the most common malignancies worldwide; however, the molecular mechanism in tumorigenesis still needs exploration. BCL2L11 belongs to the BCL-2 family, and acts as a central regulator of the intrinsic apoptotic cascade and mediates cell apoptosis. Although miRNAs have been reported to be involved in each stage of cancer development, the role of miR-24 in GC has not been reported yet. In the present study, miR-24 was found to be up-regulated while the expression of BCL2L11 was inhibited in tumor tissues of GC. Studies from both in vitro and in vivo shown that miR-24 regulates BCL2L11 expression by directly binding with 3'UTR of mRNA, thus promoting cell growth, migration while inhibiting cell apoptosis. Therefore, miR-24 is a novel onco-miRNA that can be potential drug targets for future clinical use.

Objective: miR-215 was reported to be downregulated and functioned as a tumor suppressor in several cancers. In contrast, miR-215 was preferentially upregulated in gastric cancer (GC) according to our data. Thus, we studied the potential biological function of miR-215 in GC., Methods: miR-215 expression was measured in 77 paired GC tissues and adjacent non-tumor tissues. Biological functions of miR-215 were analyzed using cell viability, colony formation, migration, invasion, cell cycle, apoptosis and luciferase assays as well as via tumorigenicity and metastasis analysis., Results: miR-215 was significantly upregulated in 7 GC cell lines and 77 GC tissues compared to adjacent non-tumor tissues (P < 0.05), and miR-215 expression was greater in advanced GC (stage III/IV; P < 0.05). Ectopic expression of miR-215 in GES-1 and HGC-27 cells (low miR-215 expression) promoted cell growth, migration, invasion, and metastasis, and these were reversed in NCI-N87 cells (high miR-215 expression) after miR-215 downregulation. Potential target genes of miR-215 were predicted and RUNX1, a transcription factor and a tumor suppressor, was confirmed to be potential target according to luciferase studies. RUNX1 was downregulated in GC tissues compared to adjacent non-tumor tissues (P < 0.05), and RUNX1 reversed partial function of miR-215 in vitro., Conclusions: miR-215 promotes malignant progression of GC by targeting RUNX1, and RUNX1 can partially reverse miR-215 effects.

Background: MicroRNAs (miRNAs) have been demonstrated to play a crucial role in tumorigenesis. Previous studies have shown that miR-520b/e acts as a tumor suppressor in several tumors. Other studies indicated that epidermal growth factor receptor (EGFR) is highly expressed in many tumors, and involved in the development of tumors, such as cell proliferation, migration, angiogenesis and apoptosis. However, the correlation of miRNAs and EGFR in gastric cancer (GC) has not been adequately investigated. Our aim was to explore the relationship., Methods: The expression levels of EGFR and miR-520b/e were examined by RT-PCR and Western blot. We also investigated the relationship between EGFR and miR-520b/e in GC cell lines by relevant experiments., Results: In this study, we found that miR-520b/e inhibits the protein expression of EGFR by directly binding with the 3'-untranslated region (3'-UTR). And it was shown that the down-regulation of miR-520b/e promotes cell proliferation and migration by negative regulation of the EGFR pathway, while over-expression of miR-520b/e inhibits these properties. In addition, the biological function of EGFR in GC cell lines was validated by silencing and over-expression assays respectively., Conclusions: Taken together, our results demonstrate that miR-520b/e acts as a tumor suppressor by regulating EGFR in GC, and provide a novel marker and insight for the potential therapeutic target of GC., (© 2016 The Author(s) Published by S. Karger AG, Basel.)

Objective: As the new oral selective VEGFR tyrosine kinase inhibitor, axitinib (AG-013736) exerts powerful antitumor activity in multiple solid tumors, while its' effect was unclear in gastric cancer. We aimed to investigate the antitumor activity of axitinib alone or combined with chemotherapeutic drugs against human gastric cancer cells in vitro and in vivo., Methods: The IC50 values of drugs were determined by MTS assay. The median effect of Chou-Talalay was used to assess the synergistic effect of two drugs. Flow cytometry was employed to analyze cell cycle and cell apoptosis. Cell senescence and microvessel density were evaluated by SA-β-gal staining and CD34 staining, respectively. BGC-823-derived xenografts in nude mice were established to investigate the effects of drugs in vivo., Results: Axitinib alone could inhibit cell proliferation and retard tumor growth through inducing cell cycle arrest at G2/M phase, cell senescence, cell apoptosis, and antiangiogenesis in vitro and in vivo. Axitinib combined with 5-fluorouracil (5-FU) had synergistic inhibitory effect compared to axitinib or 5-FU alone. However, the highest inhibitory effect was found between axitinib and cisplatin (inhibitory ratio >80 % compared to control), which was significantly higher than any single drug (inhibitory ratio for single 5-FU, cisplatin, and axitinib >10, >40, and >40 %, respectively, compared to control) or axitinib combined with 5-FU (inhibitory ratio >50 % compared to control)., Conclusion: We highlighted for the first time that axitinib alone or in combination with 5-fluorouracil or cisplatin has potent antitumor activity against human gastric cancer in vitro and in vivo, which provided solid evidence for future clinical trial.

Background: Karyotyping and phenotyping of circulating tumor cells (CTCs) in therapeutic cancer patients is of particular clinical significance in terms of both identifying chemo-resistant CTC subtypes and understanding CTC evolution., Methods: The integrated subtraction enrichment (SET) and immunostaining-fluorescence in situ hybridization (iFISH) platform was applied to detect and characterize CTCs in patients with advanced gastric cancer (AGC). Status of human epidermal growth factor receptor 2 (HER2) expressing and aneuploidy of chromosome 8 in CTCs enriched from the patients was examined by SET-iFISH following clinical chemotherapy or HER2-targeted therapy. CellSearch system was applied as a reference control., Results: Phenotyping of CTCs in HER2 positive AGC patients demonstrated that HER2⁺ CTCs could be effectively eliminated in response to HER2-targeted therapy. Karytotyping of CTCs indicated that distinct CTCs with different ploidies of chromosomes 8 in AGC patients correlated to either sensitivity or resistance of paclitaxel or cisplatin-based chemotherapy. Examination of the copy number of chromosome 8 in CTCs provides a potential approach for predicting chemotherapeutic efficacy and monitoring chemo-resistance., Conclusions: Phenotyping and karyotyping of the enriched CTCs upon ploidy of chromosome 8 or HER2 expression is of clinical potential for monitoring chemo-resistance and evaluating therapeutic efficacy for AGC patients.

We previously identified five miRNAs (miR-1, miR-20a, miR-27a, miR-34a, and miR-423-5p) that are up-regulated in gastric cancer. The goal of this study was to investigate the value of these miRNAs as potential biomarkers for predicting chemosensitivity and prognosis in metastatic or recurrent gastric cancer patients who received first-line chemotherapy. A total of 82 patients with metastatic or recurrent GC receiving first-line chemotherapy were included in our study. The expression levels of the five miRNAs were evaluated using hydrolysis probe-based stem-loop quantitative reverse transcription polymerase chain reaction (qRT-PCR) in individual samples before first-line chemotherapy. Patients receiving first-line chemotherapy with fluoropyrimidine combined with oxaliplatin or paclitaxel were chosen for the chemosensitivity analysis. The relationships between expression of the five-miRNAs and clinicopathological parameters, response to chemotherapy and prognosis were analyzed statistically. Patients with higher miRNA1 expression levels tended to have a higher rate of liver metastasis, and higher miRNA34a expression levels occurred more frequently in males (P = 0.022). The expression of the remaining three miRNAs showed no obvious relationship to any of the clinicopathological features. The partial response rates of the patients with high miRNA1 expression and low miRNA1 expression were 11.1% and 23.1%, respectively (P = 0.048). Similar results were observed for miRNA27a (the partial response rate was 7.7% vs. 25.9%, P = 0.018). Patients with up-regulated miRNA27a expression had a significantly worse overall survival (OS) than patients with lower miRNA27a expression (P = 0.024). In patients with MRGC, miRNA27a is a potential biomarker for predicting resistance to fluoropyrimidine-based chemotherapy and a novel prognostic marker for gastric cancer., (© 2013 Wiley Periodicals, Inc.)

Background and Aims: MET, the hepatocyte growth factor receptor, is a receptor tyrosine kinase overexpressed and activated in a subset of gastric cancer. Several studies investigated the relationship between MET amplification and expression with the clinical outcome in patients with gastric cancer, but yielded conflicting results. We performed a systematic review and meta-analysis to determine the influence of MET amplification and expression on prognosis in gastric cancer., Methods: MEDLINE and EMBASE were searched for studies that explored the association between MET amplification and expression with survival in patients with gastric cancer up to 1 April, 2013. Data of individual hazard ratios (HRs) and 95% confidence intervals (CIs) for meta-analyses were extracted from the publications and combined in pooled HRs., Results: Fourteen studies involving 2,258 patients with gastric cancer were included. It was suggested that MET overexpression had an unfavorable impact on survival of patients with gastric cancer, with HRs (95% CIs) of 2.57 (95% CI: 1.97-3.35) overall, 2.82 (95% CI: 1.86-4.27) among studies using amplification for measure scale of MET and 2.42 (95% CI: 1.66-3.54) for expression. The magnitude of association was reduced whereas remained statistically significant in high quality studies or in larger sample size studies and corresponding HRs were 2.18(1.76, 2.70) and 2.35(1.93, 2.87), respectively, without significant heterogeneity., Conclusion: The findings from present study indicated that higher MET gene amplification and expression in gastric cancer was an indicator of poor prognosis.