Unmet needs and challenges in gastric cancer: the way forward

A novel combined therapeutic strategy of Nano-EN-IR@Lip mediated photothermal therapy and stem cell inhibition for gastric cancer

Recurrence and metastasis of gastric cancer is a major therapeutic challenge for treatment. The presence of cancer stem cells (CSCs) is a major obstacle to the success of current cancer therapy, often leading to treatment resistance and tumor recurrence and metastasis. Therefore, it is important to develop effective strategies to eradicate CSCs. In this study, we developed a combined therapeutic strategy of photothermal therapy (PTT) and gastric cancer stem cells (GCSCs) inhibition by successfully synthesizing nanoliposomes loaded with IR780 (photosensitizer) and EN4 (c-Myc inhibitor). The nanocomposites are biocompatible and exhibit superior photoacoustic (PA) imaging properties. Under laser irradiation, IR780-mediated PTT effectively and rapidly killed tumor cells, while EN4 synergistically inhibited the self-renewal and stemness of GCSCs by suppressing the expression and activity of the pluripotent transcription factor c-Myc, preventing the tumor progression of gastric cancer. This Nano-EN-IR@Lip is expected to be a novel clinical nanomedicine for the integration of gastric cancer diagnosis, treatment and prevention.

Anticancer Effects of α-Pinene in AGS Gastric Cancer Cells

Gastric cancer is the fifth most common cancer globally and the third leading cause of cancer-related mortality. Existing treatment strategies for gastric cancer often present numerous side effects. Consequently, recent studies have shifted toward devising new treatments grounded in safer natural substances. α-Pinene, a natural terpene found in the essential oils of various plants, such as Lavender angustifolia and Satureja myrtifolia, displays antioxidant, antibiotic, and anticancer properties. Yet, its impact on gastric cancer remains unexplored. This research assessed the effects of α-pinene in vitro using a human gastric adenocarcinoma cell-line (AGS) human gastric cancer cells and in vivo via a xenograft mouse model. The survival rate of AGS cells treated with α-pinene was notably lower than that of the control group, as revealed by the 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide assay. This decline in cell viability was linked to apoptosis, as verified by 4',6-diamidino-2-phenylindole and annexin V/propidium iodide staining. The α-pinene-treated group exhibited elevated cleaved-poly (ADP-ribose) polymerase and B cell lymphoma 2 (Bcl-2)-associated X (Bax) levels and reduced Bcl-2 levels compared with the control levels. Moreover, α-pinene triggered the activation of extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38 within the mitogen-activated protein kinase (MAPK) pathway. In the xenograft mouse model, α-pinene induced apoptosis through the MAPK pathway, devoid of toxicity. These findings position α-pinene as a promising natural therapeutic for gastric cancer.

Pro-tumorigenic activity of PYCR1 in gastric cancer through regulating the PI3K/AKT signaling

Background

The primary objective of this investigation was to assess the impact of pyrroline-5-carboxylate reductase 1 (PYCR1) on the progression of gastric cancer (GC), specifically focusing on tumor growth and metastatic potential.

Methods

Surgical specimens from patients with different stages of GC were assayed for PYCR1 expression using immunohistochemistry. PYCR1 expression was manipulated by depletion or overexpression approaches in GC cells, and these cells were applied to explore the functional roles of PYCR1. Expression of apoptosis- and metastasis-related markers was quantified through quantitative real-time PCR and Western blot.

Results

Higher PYCR1 expression was ascertained in surgical specimens from patients with GC as compared to noncancerous adjacent tissues. Additionally, PYCR1 overexpression in GC tissues was linked to adverse clinical outcomes. The depletion of PYCR1 in GC cells resulted in a pronounced reduction in proliferation, the induction of apoptosis, and the attenuation of invasion and metastasis. Conversely, its ectopic expression notably augmented proliferation, restricted apoptosis, and stimulated invasion and metastasis. In addition, the knockdown of PYCR1 resulted in a significant elevation in the activation of caspase 3, a key protein involved in apoptosis. This depletion also led to a decrease in the activation or expression of proteins associated with metastasis, such as phosphorylated (p)-phosphatidylinositol 3-kinase (PI3K), p-AKT serine/threonine kinase (AKT), and snail family transcriptional repressor 1 (Snail). Additionally, it resulted in an upregulation of E-cadherin expression. Conversely, the overexpression of PYCR1 notably increased the levels of p-PI3K, p-AKT, and Snail, while simultaneously reducing E-cadherin expression.

Conclusion

PYCR1, by activating PI3K/AKT signaling, assumes a crucial role in governing malignant characteristics of GC cells, including proliferation, apoptosis, and metastasis. These findings underscore the promising potential of PYCR1 as a diagnostic biomarker and a target for tailored therapeutic interventions in patients with GC.

Navigating the Future: A Comprehensive Review of Artificial Intelligence Applications in Gastrointestinal Cancer

This comprehensive review explores the transformative role of artificial intelligence (AI) in the realm of gastrointestinal cancer. Gastrointestinal cancers present unique challenges, necessitating precise diagnostic tools and personalized treatment strategies. Leveraging AI, particularly machine learning and deep learning algorithms, has demonstrated remarkable potential in revolutionizing early detection, treatment planning, prognosis, and drug development. The analysis of current research and technological advancements underscores the capacity of AI to unravel intricate patterns within extensive datasets, providing actionable insights that enhance diagnostic accuracy and treatment efficacy. The transformative impact of AI on the landscape of gastrointestinal cancer is emphasized, signaling a paradigm shift towards more precise and targeted cancer care. The conclusion emphasizes the need for sustained research efforts and collaborative initiatives among AI researchers, healthcare professionals, and policymakers. By fostering interdisciplinary collaboration, we can navigate the evolving field of gastrointestinal cancer care, embracing the potential of AI to improve patient outcomes and contribute to a more effective and personalized approach to cancer management.

Neoadjuvant Chemotherapy Improves Oncological Outcomes and Long-Term Survival Among Elderly Patients with Locally Advanced Gastric Cancer: A Propensity Score Matched Analysis

INTRODUCTION

In the USA, approximately half of newly diagnosed patients with GC are 75 years or older. The objective of the current population-based study was to investigate the impact of neoadjuvant chemotherapy (NAC) on the outcomes of elderly patients with locally advanced GC.

PATIENTS AND METHODS

Patients aged > 75 years were identified from the National Cancer Database (NCDB). The primary outcome of the study was overall survival (OS). Secondary outcomes included lymph node (LN) harvest, surgical margin status, and 30-day mortality. To minimize the effect of selection bias on the assessed outcome between the two study groups (NAC versus no NAC), propensity score matching (PSM) was performed.

RESULTS

After PSM, a total of 1958 patients were included in both groups. NAC utilization increased from 2013 to 2019 (21% versus 42.7%, ptrend < 0.001). On pathologic analysis, patients who received NAC were more likely to have ≥ 16 LNs evaluated (NAC 60.1% versus no NAC 55.5%, p = 0.044) and negative resection margins (NAC 88.6% versus no NAC 83%, p = 0.001). Patients who received NAC were also less likely to experience 30-day mortality following resection (NAC 4.1% versus no NAC 7.1%). Receipt of NAC was associated with improved 1-year (73.9% versus 68.3%), 3-year (48.2% versus 43.5%), and 5-year OS (36.9% versus 30.5%) compared with patients who underwent upfront surgery (p = 0.01).

CONCLUSIONS

Receipt of NAC was associated with improved oncological outcomes among elderly patients undergoing resection for locally advanced GC.

Curcumin-encapsulated fish gelatin-based microparticles from microfluidic electrospray for postoperative gastric cancer treatment

Gastric cancer is the fifth most frequently diagnosed malignant neoplasm and the third leading cause of cancer-related mortality. Nevertheless, the therapeutic efficacy of conventional surgical and chemotherapeutic interventions in clinical practice is often unsatisfactory. Curcumin (Cur) has shown promise as a therapeutic agent in prior studies. However, its progress in this context has been impeded by challenges including low solubility, instability in aqueous environments, and rapid metabolism. In this study, we develop methacrylate fish gelatin (FGMA) hydrogel microparticles (FGMPs@Cur) encapsulating Cur via microfluidic electrospray technology for postoperative comprehensive treatment of gastric cancer. Comprehensive characterizations and analyses were conducted to assess the cytotoxicity against gastric cancer cells and potential tissue reparative effects of FGMPs@Cur. In vitro experiments revealed that FGMPs@Cur exhibited a remarkable cytotoxic effect on nearly 80 % of gastric cancer cells while maintaining at least 95 % viability of normal cells in cell compatibility tests. In vivo results demonstrated that FGMPs@Cur significantly reduced tumor volume to 47 % of the control group, and notable tissue regeneration was observed at the surgical site. These properties indicated that such a hydrogel microparticle system is a promising candidate for postoperative gastric cancer treatment in practical application.

"Hurdles race for CAR T-cell therapy in digestive tract cancer"

Digestive tract cancers (DTC) belong to the most investigated family of tumors. The incidence, prevalence, and mortality rate of DTC remain high, especially for patients with pancreatic cancer. Even though immunotherapy such as immune checkpoint inhibitors (ICI) have revolutionized the treatment of solid cancer types, ICI are still restricted to a very small group of patients and seem to be more efficacious in combination with chemotherapy. Cellular immunotherapy such as CAR T-cell therapy has entered clinical routine in hematological malignancies with outstanding results. There is growing interest on translating this kind of immunotherapy and success into patients with solid malignancies, such as DTC. This review attempts to describe the major advances in preclinical and clinical research with CAR T cells in DTC, considering the most relevant hurdles in each subtype of DTC.

A novel adenosine signalling-based prognostic signature in gastric cancer and its association with cancer immune features and immunotherapy response

Reliable prognostic signatures that can reflect the intrinsic characteristics of gastric cancer (GC) are still rare. Here, we developed an adenosine-based prognostic signature and explored its association with the tumour immune in GC patients, aiming at confirming the prognostic value of adenosine-related genes and guiding the GC risk stratification and immunotherapeutic response prediction. We collected adenosine pathway-related genes from STRING websites and manual searching. We enrolled the The Cancer Genome Atlas cohort and four gene expression omnibus cohorts of GC for generating and validating the adenosine pathway-based signature using the Cox regression method. Gene expression in the signature was verified using polymerase chain reaction. We also performed gene set enrichment analysis, immune infiltration assessment and immunotherapy response prediction based on this signature. Our study resulted in a six-gene adenosine signature (GNAS, CXCR4, PPP1R1B, ADCY6, NT5E and NOS3) for risk stratification of GC prognosis, with the highest area under the receiver operating characteristic curve up to 0.767 for predicting 10-year overall survival (OS). In the training cohort, patients with signature-defined high risk had significantly poorer OS than those with low risk (p < .001). Multivariate analysis identified the signature as an independent prognostic factor (hazard ratio 2.863, 95% confidence interval [1.871-4.381], p < .001). These findings were confirmed in four independent cohorts. Expression detection showed that all signature genes were upregulated in both GC tissues and cell lines. Further analysis revealed that the signature-defined high-risk patients were characterised by immunosuppressive states and associated with a poor immunotherapy response. In conclusion, the adenosine pathway-based signature represents a promising risk stratification tool for GC in guiding individualised prognostication and immunotherapy.

Predictors of survival outcomes among patients with gastric cancer in a leading tertiary, teaching and referral hospital in Kenya

INTRODUCTION

The incidence of gastrointestinal malignancies in Kenya is increasing, although there is a paucity of data on survival outcomes among gastric cancer patients. Hence, this study aimed to assess survival outcomes among adult gastric cancer patients at Kenyatta National Hospital.

METHODS

A retrospective cohort study design was used to assess the survival outcomes among 247 gastric cancer patients. All medical records of adult (≥18 years) gastric cancer patients with complete medical records of diagnosis, stage of cancer, and treatment regimen in the study setting in the last 5 years (2016-2020) were included. A simple random sampling technique was employed to select the study participants. Data were collected using a data abstraction tool composed of socio-demographic and clinical characteristics. Survival outcomes were reported as the percentage of mortality, mean survival estimate, and mean cancer-specific survival. The data were entered and analyzed using version 20.0 SPSS statistical software. The mean survival estimates and predictors of mortality were computed using the Kaplan-Meier and Cox regression analysis.

RESULTS

The study showed that 33.3% (64) had new distant metastasis, and 42.1% (104) had disease progression. Besides, the mortality rate was high (33.6%), and 14.6% and 7.7% of patients had complete and partial responses, respectively. The five-year survival was 32.7% among gastric cancer patients. Comorbidity (p = 0.014), advanced-stage diseases (p = 0.03), chemotherapy (p = 0.008), and gastrectomy (p = 0.016) were significant determinants of mortality.

CONCLUSIONS

A significant proportion of patients had distant metastasis, disease progression, and a low five-year survival rate. Hence, early cancer-screening programs are indispensable to circumvent disease progression and improve survival outcomes.

Risk prediction model of peritoneal seeding in advanced gastric cancer: A decision tool for diagnostic laparoscopy

BACKGROUND

Selective diagnostic laparoscopy in gastric cancer patients at high risk of peritoneal metastasis is essential for optimal treatment planning. In this study available clinicopathologic factors predictive of peritoneal seeding in advanced gastric cancer (AGC) were identified, and this information was translated into a clinically useful tool.

METHODS

Totally 2833 patients underwent surgery for AGC between 2003 and 2013. The study identified clinicopathologic factors associated with the risk of peritoneal seeding for constructing nomograms using a multivariate logistic regression model with backward elimination. A nomogram was constructed to generate a numerical value indicating risk. Accuracy was validated using bootstrapping and cross-validation.

RESULTS

The proportion of seeding positive was 12.7% in females and 9.6% in males. Of 2833 patients who underwent surgery for AGC, 300 (10.6%) were intraoperatively identified with peritoneal seeding. Multivariate analysis revealed the following factors associated with peritoneal seeding: high American Society of Anesthesiologists score, fibrinogen, Borrmann type 3 or 4 tumors, the involvement of the middle, anterior, and greater curvature, cT3 or cT4cN1 or cN2 or cN3, cM1, and the presence of ascites or peritoneal thickening or plaque or a nodule on the peritoneal wall on computed tomography. The bootstrap analysis revealed a robust concordance between mean and final parameter estimates. The area under the ROC curve for the final model was 0.856 (95% CI, 0.835-0.877), which implies good performance.

CONCLUSIONS

This nomogram provides effective risk estimates of peritoneal seeding from gastric cancer and can facilitate individualized decision-making regarding the selective use of diagnostic laparoscopy.

Integration of transcriptomics, proteomics, and metabolomics data to reveal HER2-associated metabolic heterogeneity in gastric cancer with response to immunotherapy and neoadjuvant chemotherapy

Background

Currently available prognostic tools and focused therapeutic methods result in unsatisfactory treatment of gastric cancer (GC). A deeper understanding of human epidermal growth factor receptor 2 (HER2)-coexpressed metabolic pathways may offer novel insights into tumour-intrinsic precision medicine.

Methods

The integrated multi-omics strategies (including transcriptomics, proteomics and metabolomics) were applied to develop a novel metabolic classifier for gastric cancer. We integrated TCGA-STAD cohort (375 GC samples and 56753 genes) and TCPA-STAD cohort (392 GC samples and 218 proteins), and rated them as transcriptomics and proteomics data, resepectively. 224 matched blood samples of GC patients and healthy individuals were collected to carry out untargeted metabolomics analysis.

Results

In this study, pan-cancer analysis highlighted the crucial role of ERBB2 in the immune microenvironment and metabolic remodelling. In addition, the metabolic landscape of GC indicated that alanine, aspartate and glutamate (AAG) metabolism was significantly associated with the prevalence and progression of GC. Weighted metabolite correlation network analysis revealed that glycolysis/gluconeogenesis (GG) and AAG metabolism served as HER2-coexpressed metabolic pathways. Consensus clustering was used to stratify patients with GC into four subtypes with different metabolic characteristics (i.e. quiescent, GG, AAG and mixed subtypes). The GG subtype was characterised by a lower level of ERBB2 expression, a higher proportion of the inflammatory phenotype and the worst prognosis. However, contradictory features were found in the mixed subtype with the best prognosis. The GG and mixed subtypes were found to be highly sensitive to chemotherapy, whereas the quiescent and AAG subtypes were more likely to benefit from immunotherapy.

Conclusions

Transcriptomic and proteomic analyses highlighted the close association of HER-2 level with the immune status and metabolic features of patients with GC. Metabolomics analysis highlighted the co-expressed relationship between alanine, aspartate and glutamate and glycolysis/gluconeogenesis metabolisms and HER2 level in GC. The novel integrated multi-omics strategy used in this study may facilitate the development of a more tailored approach to GC therapy.

The Expression and Prognostic Significance of VEGF and CXCR4 in Gastric Cancer: Correlation with Angiogenesis, Lymphangiogenesis and Progression

The cellular response to hypoxia includes the expression of hypoxia-inducible factor-1 (HIF-1) and its target genes: vascular endothelial growth factor (VEGF) and CXC chemokine receptor 4 (CXCR4). The aim of this study was to investigate the expression and prognostic significance of VEGF and CXCR4, which are responsible for angiogenesis and progression in gastric cancer. Twenty-eight gastric cancer patients were analyzed. The mRNA expression was examined in primary tumors and corresponding normal gastric mucosa by RT-PCR. The protein level was examined by immunohistochemistry staining. The high expression of VEGF and CXCR4 was found in 71.0 and 64.0% of tumors, respectively. The mean levels of VEGF and CXCR4 were upregulated in primary tumors compared to normal mucosa (p = 0.0007, p = 0.0052). A correlation between VEGF expression and tumor invasion (p = 0.0216) and stage (p = 0.0181) was found. CXCR4 expression correlated with lymph node metastases (p = 0.0237) and stage (p = 0.0054). The VEGF expression correlated with microvessel density (MVD) (p = 0.0491). The overall 3-year survival rate was 46.4% and correlated negatively with high CXCR4 mRNA expression (p = 0.0089). VEGF and CXCR4 play an important role in tumor progression. Their overexpression correlates with a bad prognosis and may improve high-risk patient selection, and these patients may obtain additional survival benefits if treated more aggressively.

Evaluation of CSTB and DMBT1 expression in saliva of gastric cancer patients and controls

Background

Gastric cancer (GC) is the fifth most common cancer and the third cause of cancer deaths globally, with late diagnosis, low survival rate, and poor prognosis. This case-control study aimed to evaluate the expression of cystatin B (CSTB) and deleted in malignant brain tumor 1 (DMBT1) in the saliva of GC patients with healthy individuals to construct diagnostic algorithms using statistical analysis and machine learning methods.

Methods

Demographic data, clinical characteristics, and food intake habits of the case and control group were gathered through a standard checklist. Unstimulated whole saliva samples were taken from 31 healthy individuals and 31 GC patients. Through ELISA test and statistical analysis, the expression of salivary CSTB and DMBT1 proteins was evaluated. To construct diagnostic algorithms, we used the machine learning method.

Results

The mean salivary expression of CSTB in GC patients was significantly lower (115.55 ± 7.06, p = 0.001), and the mean salivary expression of DMBT1 in GC patients was significantly higher (171.88 ± 39.67, p = 0.002) than the control.

Multiple linear regression analysis demonstrated that GC was significantly correlated with high levels of DMBT1 after controlling the effects of age of participants (R² = 0.20, p < 0.001).

Considering salivary CSTB greater than 119.06 ng/mL as an optimal cut-off value, the sensitivity and specificity of CSTB in the diagnosis of GC were 83.87 and 70.97%, respectively. The area under the ROC curve was calculated as 0.728. The optimal cut-off value of DMBT1 for differentiating GC patients from controls was greater than 146.33 ng/mL (sensitivity = 80.65% and specificity = 64.52%). The area under the ROC curve was up to 0.741.

As a result of the machine learning method, the area under the receiver-operating characteristic curve for the diagnostic ability of CSTB, DMBT1, demographic data, clinical characteristics, and food intake habits was 0.95. The machine learning model’s sensitivity, specificity, and accuracy were 100, 70.8, and 80.5%, respectively.

Conclusion

Salivary levels of DMBT1 and CSTB may be accurate in diagnosing GCs. Machine learning analyses using salivary biomarkers, demographic, clinical, and nutrition habits data simultaneously could provide affordability models with acceptable accuracy for differentiation of GC by a cost-effective and non-invasive method.

Identification of a novel m6A-related lncRNA pair signature for predicting the prognosis of gastric cancer patients

Background

Accumulating studies have demonstrated that lncRNAs play vital roles in the prognosis of gastric cancer (GC); however, the prognostic value of N6-methyladenosine-related lncRNAs has not been fully reported in GC. This study aimed to construct and validate an m6A-related lncRNA pair signature (m6A-LPS) for predicting the prognosis of GC patients.

Methods

GC cohort primary data were downloaded from The Cancer Genome Atlas. We analysed the coexpression of m6A regulators and lncRNAs to identify m6A-related lncRNAs. Based on cyclical single pairing along with a 0-or-1 matrix and least absolute shrinkage and selection operator-penalized regression analyses, we constructed a novel prognostic signature of m6A-related lncRNA pairs with no dependence upon specific lncRNA expression levels. All patients were divided into high-risk and low-risk group based on the median risk score. The predictive reliability was evaluated in the testing dataset and whole dataset with receiver operating characteristic (ROC) curve analysis. Gene set enrichment analysis was used to identify potential pathways.

Results

Fourteen m6A-related lncRNA pairs consisting of 25 unique lncRNAs were used to construct the m6A-LPS. Kaplan–Meier analysis showed that the high-risk group had poor prognosis. The area under the curve for 5-year overall survival was 0.906, 0.827, and 0.882 in the training dataset, testing dataset, and whole dataset, respectively, meaning that the m6A-LPS was highly accurate in predicting GC patient prognosis. The m6A-LPS served as an independent prognostic factor for GC patients after adjusting for other clinical factors (p < 0.05). The m6A-LPS had more accuracy and a higher ROC value than other prognostic models for GC. Functional analysis revealed that high-risk group samples mainly showed enrichment of extracellular matrix receptor interactions and focal adhesion. Moreover, N-cadherin and vimentin, known biomarkers of epithelial–mesenchymal transition, were highly expressed in high-risk group samples. The immune infiltration analysis showed that resting dendritic cells, monocytes, and resting memory CD4 T cells were significantly positively related to the risk score. Thus, m6A-LPS reflected the infiltration of several types of immune cells.

Conclusions

The signature established by pairing m6A-related lncRNAs regardless of expression levels showed high and independent clinical prediction value in GC patients.

Ethanol Extract of Eryngium Foetidum Leaves Induces Mitochondrial Associated Apoptosis via ROS Generation in Human Gastric Cancer Cells

Background: Eryngium foetidum has long been used as a food ingredient and folk medicine in tropical regions. The anticancer activity of EF extract and the mechanisms remains unclear. Herein, we prepared four solvent extracts of EF leaves, detected the cytotoxic effects, and explored the potential mechanism by which these extracts induce cell death. Methods: The anticancer activity of the EF extracts was measured by MTT, CCK-8 and BrdU assays. The cell cycle was evaluated by flow cytometry and western blot. Apoptotic events were investigated with Hoechst, Annexin V/PI assays and western blot. The mitochondrial membrane potential was monitored using JC-1 staining, and ROS production was assessed with immunofluorescence. Results: The ethanol extract of EF leaves exhibited the strongest cytotoxic effect against SGC-7901 cells. The EFE extract significantly inhibited the SGC-7901 cells viability, arrested the cell cycle, increased the numbers of apoptotic cells, caused the loss of MMP, increased the Bax/Bcl-2 ratio, and led to cytochrome c release, and triggered ROS production. Conclusion: Our findings demonstrated for the first time that EFE extract induces mitochondrial associated apoptosis via ROS generation in SGC-7901 cells. Thus, EFE extract could be identified as a potential edible phytotherapy for the treatment of human gastric cancer.

Palliative Gastrectomy vs. Gastrojejunostomy for Advanced Gastric Cancer: A Systematic Review and Meta-Analysis

Background: Advanced gastric cancer is the fifth leading cause of cancer-related deaths. Patients with metastatic advanced gastric cancer commonly develop a gastric outlet obstruction that considerably worsens their quality of life. Surgical interventions such as gastrojejunostomy and palliative gastrectomy are commonly administered to alleviate this obstruction. However, whether one intervention is better than another at improving morbidity- and mortality-related outcomes is unclear. Thus, in this meta-analysis, we compare outcomes of palliative gastrectomy and gastrojejunostomy (overall hospital stay length, time to oral intake, survival, and complication rates) in patients with metastatic advanced gastric cancer to identify the best procedure.

Objective: To compare morbidity and mortality outcomes of palliative gastrectomy and gastrojejunostomy in patients with metastatic advanced gastric cancer.

Methods: We followed the PRISMA guidelines to systematically search Web of Science, EMBASE, CENTRAL, Scopus, and MEDLINE for relevant studies. We conducted a random-effects meta-analysis to find differential outcomes between palliative gastrectomy and gastrojejunostomy among variables such as time to oral intake, overall hospital stay length, complication rates, and survival in patients with metastatic advanced gastric cancer.

Results: From 963 studies, we found 7 eligible studies with 642 patients (70.3 ± 4.7 years) who had undergone palliative gastrectomy or gastrojejunostomy. Our meta-analysis revealed an insignificant (p > 0.05) differences in terms of overall survival duration (Hedge's g, 1.22), complication risks (odds ratio, 1.35), and time to oral intake (g, 0.62) and hospital stay length (g, 0.12) between patients undergoing gastrojejunostomy and palliative gastrectomy.

Conclusion: In this present study we observed no statistically significant differences in terms of morbidity and mortality outcomes after palliative gastrectomy and gastrojejunostomy in patients with metastatic advanced gastric cancer. Therefore, no conclusions can be drawn for the variables evaluated. This study provides a preliminary overview of the risks associated with gastrojejunostomy and palliative gastrectomy to help gastroenterologists manage patients with metastatic advanced-stage gastric cancer.

Circ_0021087 acts as a miR-184 sponge and represses gastric cancer progression by adsorbing miR-184 and elevating FOSB expression

BACKGROUND

Gastric cancer (GC) ranks third among the causes of cancer-related deaths in the world. Circular RNA hsa_circ_0021087 (circ_0021087) plays a repressive role in GC. Nevertheless, the mechanism by which circ_0021087 constrains GC advancement is unclear.

MATERIALS AND METHODS

Expression patterns of circ_0021087, microRNA (miR)-184 and FBJ murine osteosarcoma viral oncogene homolog B (FOSB) mRNA were assessed by quantitative real-time polymerase chain reaction (RT-qPCR). Gain-of-function experiments were conducted to verify the biological function of circ_0021087 in vitro and in vivo, including cell counting kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), flow cytometry, transwell and xenograft assays. Protein levels were analysed by Western blotting and immunohistochemistry (IHC). The regulatory mechanism of circ_0021087 was analysed by bioinformatics analysis, dual-luciferase reporter and RNA immunoprecipitation (RIP) assays.

RESULTS AND CONCLUSION

Circ_0021087 and FOSB were lowly expressed in GC, whereas miR-184 had an opposite result. Circ_0021087 overexpression repressed GC cell proliferation and epithelial-mesenchymal transition (EMT) in xenograft models in vivo and induced GC cell apoptosis, repressed GC cell proliferation, EMT, migration and invasion in vitro. Circ_0021087 could elevate FOSB expression by adsorbing miR-184. MiR-184 mimic reversed the inhibitory influence of circ_0021087 overexpression on GC cell malignancy. Also, FOSB knockdown offset the suppressive impact of miR-184 silencing on GC cell malignancy. In conclusion, circ_0021087 played a repressive influence on GC progression by elevating FOSB expression by adsorbing miR-184, offering a new mechanism for circ_0021087 to inhibit the progression of GC.

The Role of CAR-T Cells in Peritoneal Carcinomatosis from Gastric Cancer: Rationale, Experimental Work, and Clinical Applications

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) have shown poor effectiveness in treating peritoneal carcinomatosis (PC) of gastric origin with a high tumor burden (high peritoneal cancer index), though there are scarce therapy alternatives that are able to improve survival. In experimental studies, chimeric antigen receptor-T (CAR-T) cell therapy has shown encouraging results in gastric cancer and is currently being evaluated in several clinical trials. Regarding PC, CAR-T cell therapy has also proven useful in experimental studies, especially when administered intraperitoneally, as this route improves cell distribution and lifespan. Although these results need to be supported by ongoing clinical trials, CAR-T cells are a promising new therapeutic approach to peritoneal metastases from gastric cancer. In this review, we summarize the current evidence of the use of CAR-T cells in gastric cancer and PC of gastric origin.

Apatinib inhibits the proliferation of gastric cancer cells via the AKT/GSK signaling pathway in vivo

Gastric cancer (GC) is the third leading cause of cancer-associated mortality globally. Although the diagnosis and therapeutic strategies for GC have improved, the prognosis for advanced gastric cancer (AGC) remains poor. Hence, the present study sought to design a zebrafish model established by microinjecting human MGC-803 GC cell line for studying personalized molecular-targeted cancer therapy. Apatinib, a novel molecular-targeted agent, was evaluated for its in vivo efficacy through a comparison among the control groups (no treatment) and subject groups (treatment). Newly formed vessel length and tumor volume were measured in all of the groups for further study. The length of newly formed vessels was obviously shortened after apatinib treatment in the zebrafish model established in this study. Meanwhile, apatinib exhibited the best antitumor growth effect with dose and time dependence by suppressing AKT/GSK3α/β signaling, which may be the mechanism underlying the profound antitumor clinical effect of apatinib. The data indicated that apatinib therapy exerts an anti-angiogenesis effect and it can be recommended as a proper antitumor growth therapy for GC patients. Additionally, zebrafish models could be designed as a potential practical tool to explore new anti-GC cancer drugs.

Molecularly Targeted Therapies for Gastric Cancer. State of the Art

Many phase III trials failed to demonstrate a survival benefit from the addition of molecular therapy to conventional chemotherapy for advanced and metastatic gastric cancer, and only three agents were approved by the FDA. We examined the efficacy and safety of novel drugs recently investigated. PubMed, Embase and Cochrane Library were searched for phase III randomized controlled trials published from January 2016 to December 2020. Patients in the experimental arm received molecular therapy with or without conventional chemotherapy, while those in the control arm had conventional chemotherapy alone. The primary outcomes were overall and progression-free survival. The secondary outcomes were the rate of tumor response, severe adverse effects, and quality of life. Eight studies with a total of 4223 enrolled patients were included. The overall and progression-free survival of molecular and conventional therapy were comparable. Most of these trials did not find a significant difference in tumor response rate and in the number of severe adverse effects and related deaths between the experimental and control arms. The survival benefits of molecular therapies available to date for advanced and metastatic gastric cancer are rather unclear, mostly due to inaccurate patient selection, particularly concerning oncogene amplification and copy number.

LINC01133 hampers the development of gastric cancer through increasing somatostatin via binding to microRNA-576-5p

Aim: Our study aimed at investigating how LINC01133 functions in gastric cancer (GC) progression. Materials & methods: Gain-of-function and loss-of-function approaches were applied to analyze the effects of LINC01133, microRNA-576-5p (miR-576-5p) and somatostatin (SST) on the biological behaviors of GC cells and in tumor-bearing nude mice. Results: GC tissues and cells showed low expression of LINC01133, and LINC01133 overexpression decreased malignant phenotypes of GC cells. Moreover, LINC01133 upregulated SST through binding to miR-576-5p. Overexpressing miR-576-5p or suppressing SST reversed the functions of LINC01133 in biological potentials of GC cells and tumor growth. Conclusion: LINC01133 overexpression may inhibit GC development by downregulation of miR-576-5p and upregulation of SST, which suggests new therapeutic targets for GC.

Apatinib Suppresses Gastric Cancer Stem Cells Properties by Inhibiting the Sonic Hedgehog Pathway

The presence of gastric cancer stem cells (GCSCs) marks the onset of gastric carcinoma. The sonic hedgehog (SHH) pathway plays a vital role in the maintenance of GCSC characteristics. Apatinib has been approved in China for advanced gastric cancer (GC) treatment. However, whether apatinib can target GCSCs and affect the SHH pathway remains unclear. The present study aimed to investigate the underlying mechanism of apatinib’s antitumor effects on GC. The expression levels of GCSC markers and number of CD133⁺ cells were significantly elevated in the sphere-forming cells. Apatinib effectively suppressed GCSC traits by inhibiting tumorsphere formation and cell proliferation, suppressing GCSC markers expression and CD133⁺ cell number, and inducing apoptosis. Apatinib downregulated the activation of the SHH pathway; while upregulation of the SHH pathway attenuated the inhibitory effects of apatinib on GCSCs. Moreover, apatinib treatment significantly delayed tumor growth and inhibited GCSC characteristics in the xenograft model. Our data suggested that apatinib exhibited inhibitory effects on GCSCs by suppressing SHH pathway both in vitro and in vivo, thus providing new insights into the therapeutic application of apatinib in GCSC suppression and advanced gastric cancer treatment.

WBP2 promotes gastric cancer cell migration via novel targeting of LATS2 kinase in the Hippo tumor suppressor pathway

Dysregulation of signaling pathways is responsible for many human diseases. The lack of understanding of the molecular etiology of gastric cancer (GC) poses a substantial challenge to the development of effective cancer therapy. To better understand the molecular mechanisms underlying the pathogenesis of GC, which will facilitate the identification and development of effective therapeutic approaches to improve patient outcomes, mass spectrometry-based phosphoproteomics analysis was performed to map the global molecular changes in GC. A total of 530 proteins with altered phosphorylation levels were detected across a panel of 15 normal and GC cell lines. WW domain-binding protein 2 (WBP2) was validated to be upregulated in a subset of GC cell lines. WBP2 is overexpressed in 61% cases of GC compared to non-cancer tissues and high WBP2 expression correlates with poor clinical outcomes. WBP2 was found to be required for GC cell migration but is dispensable for cell growth and proliferation. WBP2 knockdown increased p-LATS2 with a concomitant increase in p-YAP, resulting in the cytoplasmic retention of YAP and ultimately the inhibition of YAP/TEAD activity and downregulation of TEAD target genes--CTGF and CYR61. Importantly, the loss of LATS2 reversed the activation of Hippo pathway caused by WBP2 knockdown, indicating that WBP2 acts through LATS2 to exert its function on the Hippo pathway. Moreover, WBP2 interacted with LATS2 to inhibit its phosphorylation and activity. In conclusion, our study established a pivotal role for WBP2 in the promotion of GC cell migration via a novel mechanism that inactivates the Hippo pathway transducer LATS2.

Asporin represses gastric cancer apoptosis via activating LEF1-mediated gene transcription independent of β-catenin

Asporin (ASPN) presents in the tumor microenvironment and exhibits a cancer-promoting effect as a stroma protein. Even though ASPN has already been observed inside cancer cells, the functions of intracellular ASPN and its underlying mechanisms remain unknown. Here we reported that ASPN was upregulated in different stages of gastric cancer (GC), and associated with a poor prognosis. Moreover, we found that ASPN markedly inhibited GC cell apoptosis and promoted cell growth in vitro and in vivo. Further mechanism investigations revealed that ASPN directly binding to lymphoid enhancer-binding factor 1 (LEF1) and promoted LEF1-mediated gene transcription independent of β-catenin, the classic co-factor in the Wnt/LEF1 pathway. We also demonstrated that ASPN selectively facilitated LEF1 binding to and activating the promoters of PTGS2, IL6, and WISP1 to promote their transcription. The suppression of cell apoptosis by ASPN overexpression could be attenuated by LEF1 knockdown or 100 µM aspirin (PTGS2 inhibitor), and siASPN mediated apoptosis could be rescued by LEF1 ectopic expression or adding recombinant IL6. Therefore, we concluded that ASPN repressed GC cell apoptosis via activating LEF1-mediated gene transcription independent of β-catenin, which could serve as a potential prognostic biomarker in GC patients.

Characterization of the Prognostic m6A-Related lncRNA Signature in Gastric Cancer

N6-methyladenosine (m⁶A) is a common form of mRNA modification regulated by m6A RNA methylation regulators and play an important role in the progression of gastric cancer (GC). However, the prognostic role of m⁶A-related lncRNA in gastric cancer has not been fully explored. This study aims at exploring the biological function and prognostic roles of the m⁶A-related lncRNA signature in gastric cancer. A total of 800 m6A-related lncRNAs were identified through Pearson correlation analysis between m6A regulators and all lncRNAs. Eleven m6A-related lncRNA signatures were identified through a survival analysis and the Kaplan-Meier (KM) curve analysis results suggest that patients in the low-risk group have a better overall survival (OS) and disease-free survival (DFS) outcome than the high-risk group. Also, the lncRNA signature can serve as an independent prognostic factor for OS and DFS. The gene set enrichment analysis (GSEA) result suggests that patients in the high-risk group were mainly enriched in the ECM receptor interaction, focal adhesion, and cytokine-cytokine receptor interaction pathway, while the low-risk group was characterized by the base excision repair pathway. We further constructed an individualized prognostic prediction model via the nomogram based on the independent prognostic factor for the OS and DFS, respectively. In addition, some candidate drugs aimed at GC risk group differentiation were identified using the Connective Map (CMAP) database. Lastly, four subgroups (C1, C2, C3, and C4) were identified based on the m6A-related lncRNA expression, through a consensus clustering algorithm. Among them, C1 and C2 have a greater likelihood to respond to immune checkpoint inhibitor immunotherapy, suggesting that the C1 and C2 subgroup might benefit from immunotherapy. In conclusion, the m6A-related lncRNA signature can independently predict the OS and DFS of GC and may aid in development of personalized immunotherapy strategies.

Cancer-Associated Fibroblasts Promote Aggressive Gastric Cancer Phenotypes via Heat Shock Factor 1-Mediated Secretion of Extracellular Vesicles

Gastric cancer is the third most lethal cancer worldwide, and evaluation of the genomic status of gastric cancer cells has not translated into effective prognostic or therapeutic strategies. We therefore hypothesize that outcomes may depend on the tumor microenvironment (TME), in particular, cancer-associated fibroblasts (CAF). However, very little is known about the role of CAFs in gastric cancer. To address this, we mapped the transcriptional landscape of human gastric cancer stroma by microdissection and RNA sequencing of CAFs from patients with gastric cancer. A stromal gene signature was associated with poor disease outcome, and the transcription factor heat shock factor 1 (HSF1) regulated the signature. HSF1 upregulated inhibin subunit beta A and thrombospondin 2, which were secreted in CAF-derived extracellular vesicles to the TME to promote cancer. Together, our work provides the first transcriptional map of human gastric cancer stroma and highlights HSF1 and its transcriptional targets as potential diagnostic and therapeutic targets in the genomically stable tumor microenvironment. SIGNIFICANCE: This study shows how HSF1 regulates a stromal transcriptional program associated with aggressive gastric cancer and identifies multiple proteins within this program as candidates for therapeutic intervention. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/81/7/1639/F1.large.jpg.

Importance of Examined Lymph Node Number in Accurate Staging and Enhanced Survival in Resected Gastric Adenocarcinoma-The More, the Better? A Cohort Study of 8,696 Cases From the US and China, 2010-2016

Background

While most guidelines advocate D2 lymphadenectomy for non-metastatic gastric adenocarcinoma (nmGaC), it is not always performed as standard of care outside East Asia. The recommended minimal examined lymph node (ELN) count in nmGaC to stage cancer accurately varies largely across guidelines, and the optimal count to satisfactorily stratify patient survival has yet to be determined. This large cohort study aimed at robustly defining the minimal and optimal thresholds of examined lymph node (ELN) number in non-metastatic gastric adenocarcinoma (nmGaC).

Methods

Data on nmGaC patients operated in 2010–2016 and surviving ≥3 months were retrieved from the US SEER-18 Program and a Chinese multi-institutional gastric cancer database (MIGC). The correlation of ELN count with stage migration and patient survival were quantified with the use of the multivariable-adjusted logistic and proportional hazards Cox models, respectively. The sequences of odds ratios (ORs) and hazard ratios (HRs) for each additional ELN were smoothed, and the structural breakpoints were determined.

Results

Together 7,228 patients from the US and 1,468 from China were analyzed, encompassing 23,114 person-years of follow-up. The mean ELN count was 20 in the US and 30 in China. With more ELNs, both cohorts significantly showed proportional increases from lower to higher nodal stage (OR_SEER = 1.03, 95%-CI = 1.03–1.04; OR_MIGC = 1.02, 95%-CI = 1.02–1.03) and sequential enhancements in postoperative survival (HR_SEER = 0.97, 95%-CI = 0.97–0.97; HR_MIGC = 0.98, 95%-CI = 0.97–0.99). Correlations for both stage migration and survival were still significant in most subgroups by patient, cancer, and management factors. Breakpoint analyses revealed a minimum threshold ELN count of 17 and an optimum count of 33, which were validated in both cohorts with good efficacy to differentiate probabilities of both stage migration and survival.

Conclusion

In resected nmGaC patients with anticipated survival ≥3 months, more ELNs are correlated with more accurate staging, which may partly explain the survival correlation. This observational investigation does not indicate causality. Our findings robustly conclude 17 ELNs as the minimum and propose 33 ELNs as the optimum thresholds, to assess the quality of lymph node examination and to stratify postsurgical survival.

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

BACKGROUND

Gastric cancer (GC) is one of the most common and deadliest types of cancer worldwide due to its delayed diagnosis and high metastatic frequency, but its exact pathogenesis has not been fully elucidated. ETS homologous factor (EHF) is an important member of the ETS family and contributes to the pathogenesis of multiple malignant tumors. To date, whether EHF participates in the development of GC via the c-Met signaling pathway remains unclear.

AIM

To investigate the role and mechanism of EHF in the occurrence and development of GC.

METHODS

The expression of EHF mRNA in GC tissues and cell lines was measured by quantitative PCR. Western blotting was performed to determine the protein expression of EHF, c-Met, and its downstream signal molecules. The EHF expression in GC tissues was further detected by immunohistochemical staining. To investigate the role of EHF in GC oncogenesis, small interfering RNA (siRNA) against EHF was transfected into GC cells. The cell proliferation of GC cells was determined by Cell Counting Kit-8 and colony formation assays. Flow cytometry was performed following Annexin V/propidium iodide (PI) to identify apoptotic cells and PI staining to analyze the cell cycle. Cell migration and invasion were assessed by transwell assays.

RESULTS

The data showed that EHF was upregulated in GC tissues and cell lines in which increased expression of c-Met was also observed. Silencing of EHF by siRNA reduced the proliferation of GC cells. Inhibition of EHF induced significant apoptosis and cell cycle arrest in GC cells. Cell migration and invasion were significantly inhibited. EHF silencing led to c-Met downregulation and further blocked the Ras/c-Raf/extracellular signal-related kinase 1/2 (Erk1/2) pathway. Additionally, phosphatase and tensin homolog was upregulated and glycogen synthase kinase 3 beta was deactivated. Moreover, inactivation of signal transducer and activator of transcription 3 was detected following EHF inhibition, leading to inhibition of the epithelial-to-mesenchymal transition (EMT).

CONCLUSION

These results suggest that EHF plays a key role in cell proliferation, invasion, apoptosis, the cell cycle and EMT via the c-Met pathway. Therefore, EHF may serve as an antineoplastic target for the diagnosis and treatment of GC.

NK6 Homeobox 2 Regulated Gastrokin-2 Suppresses Gastric Cancer Cell Proliferation and Invasion via Akt Signaling Pathway

This study aims to explore the role of Gastrokin-2 (GKN2) in gastric cancer and its function in the progression and metastasis of gastric cancer. The expression of GKN2 in the patient samples was examined by qRT-PCR and western blot. The transcription factor NK6 Homeobox 2 (NKX6-2), which binds to the GKN2 promoter, was predicted by cBioportal and JSPAR. Binding between NKX6-2 and the GKN2 promoter was analyzed by dual-luciferase assay. MTT assay and transwell assay were used to detect changes in gastric cancer cell viability and migration after GKN2 overexpression, which was achieved by transfection of GKN2 overexpression vector. Akt signaling pathway markers were assessed by western blot. GKN2 is downregulated in gastric cancer and low GKN2 expression is correlated to poor survival, metastasis, and higher clinical stages. NKX6-2 binds the promoter region of GKN2 and regulate its expression. GKN2 overexpression inhibits the proliferation, migration, and invasion of gastric cancer cells, which was mediated by Akt signaling pathway. NKX6-2 regulated GKN2 inhibits the proliferation and invasion of gastric cancer cells by inhibiting Akt signaling pathway. GKN2 can be used as a potential diagnostic and therapeutic target for patients with clinical gastric cancer.

Chimeric Antigen Receptor T Cell Therapy Targeting ICAM-1 in Gastric Cancer

Cancer therapy utilizing adoptive transfer of chimeric antigen receptor (CAR) T cells has demonstrated remarkable clinical outcomes in hematologic malignancies. However, CAR T cell application to solid tumors has had limited success, partly due to the lack of tumor-specific antigens and an immune-suppressive tumor microenvironment. From the tumor tissues of gastric cancer patients, we found that intercellular adhesion molecule 1 (ICAM-1) expression is significantly associated with advanced stage and shorter survival. In this study, we report a proof-of-concept study using ICAM-1-targeting CAR T cells against gastric cancer. The efficacy of ICAM-1 CAR T cells showed a significant correlation with the level of ICAM-1 expression in target cells in vitro. In animal models of human gastric cancer, ICAM-1-targeting CAR T cells potently eliminated tumors that developed in the lungs, while their efficacy was more limited against the tumors in the peritoneum. To augment CAR T cell activity against intraperitoneal tumors, combinations with paclitaxel or CAR activation-dependent interleukin (IL)-12 release were explored and found to significantly increase anti-tumor activity and survival benefit. Collectively, ICAM-1-targeting CAR T cells alone or in combination with chemotherapy represent a promising strategy to treat patients with ICAM-1+ advanced gastric cancer.

Precision Medicine to Treat Advanced Gastroesophageal Adenocarcinoma: A Work in Progress

Gastroesophageal adenocarcinoma (GEA) represents a heterogeneous disease and, when diagnosed as locally advanced or metastatic, it is characterized by poor prognosis. During the last few years, several molecular classifications have been proposed to try to personalize treatment for those patients diagnosed with advanced disease. Nevertheless, despite the great effort, precision medicine is still far from being a reality. The improvement in the molecular analysis due to the application of high throughput technologies based on DNA and RNA sequencing has opened a novel scenario leading to the personalization of treatment. The possibility to target epidermal growth factor receptor (HER)2, Claudine, Fibroblast Growth Factor Receptors (FGFR), and other alterations with a molecular matched therapy could significantly improve clinical outcomes over advanced gastric cancer patients. On the other hand, the development of immunotherapy could also represent a promising strategy in a selected population. In this review, we sought to describe the novel pathways implicated in GEA progression and the results of the molecular matched therapies.

Long Noncoding RNA LINC01485 Promotes Tumor Growth and Migration via Inhibiting EGFR Ubiquitination and Activating EGFR/Akt Signaling in Gastric Cancer

Background

Although several long non-coding RNAs (lncRNAs) have been found to be involved in gastric cancer tumorigenesis, the more comprehensive contributions of lncRNAs to gastric cancer require further investigation. Here, we identify a cytoplasmic lncRNA, LINC01485, which promotes tumor growth and migration in gastric cancer.

Materials and Methods

Microarray and computational analysis were utilized to identify differential expression in LINC01485 and EGFR. Real-time PCR and Western blotting assays were used to confirm the expression of LINC01485 and EGFR in gastric cancer cells. Cell proliferation, wound-healing and transwell assays were performed to measure cell growth, migration and invasion. Immunoprecipitation, RNA pull-down, and RNA fluorescence in situ hybridization (RNA-FISH) assays were used to test the interaction of c-Cbl with LINC01485 and EGFR. Furthermore, tumor xenograft in nude mice was performed to test tumor growth in vivo.

Results

LINC01485 was upregulated and associated with tumor size, lymphatic metastasis and advanced pathological stage in gastric cancer. LINC01485 promoted gastric cancer cell proliferation, migration and invasion in vitro and in vivo. Furthermore, LINC01485 levels were positively correlated with EGFR expression in gastric cancer tissues and significantly increased the expression and phosphorylation (Tyr1045) of EGFR in gastric cancer cells. Mechanistically, LINC01485 competes with c-Cbl for binding to phosphorylated Tyr1045 site of EGFR, thus interfering with c-Cbl-mediated ubiquitination and subsequent degradation of EGFR.

Conclusion

LINC01485 promoted EGFR stabilization and activation of EGFR/Akt signaling in gastric cancer. Our findings illustrate the diversity of cytoplasmic lncRNAs in signal transduction and highlight the important roles of lncRNAs in gastric cancer.

Baicalein enhanced cisplatin sensitivity of gastric cancer cells by inducing cell apoptosis and autophagy via Akt/mTOR and Nrf2/Keap 1 pathway

Baicalein is a natural flavonoid with various pharmacological activities including antitumor. The synergistic anti-cancer effect of the combination of baicalein and Cisplatin (DDP) on gastric cancer (GC) has not been reported. MTT assay and colony formation assay were used to determine the inhibitory effect of the combination of baicalein and DDP on cell survival. Invasive assay was performed to test the effects of baicalein and DDP on cell invasive capability. A flow cytometric analysis was conducted to determine the apoptosis-induced effects of baicalein on GC cells, especially SGC-7901/DDP (resistant to DDP). Confocal laser microscope and real-time PCR were used to test autophagy-induced effects of baicalein on SGC-7901 and SGC-7901/DDP cells. Western blotting was performed to investigate the molecular mechanisms of baicalein inducing apoptosis and autophagy. Our study showed that baicalein could inhibit cell proliferation of MGC-803, HGC-27, SGC-7901 and SGC-7901/DDP, and the inhibitory effect was extremely enhanced when combining with DDP. Additionally, combination of baicalein and DDP suppressed the invasive capability and induced apoptosis and autophagy in both SGC-7901 and SGC-7901/DDP, and the effect was stronger than that of DDP or baicalein alone. The further molecular mechanism analysis indicated that baicalein modulated the activities of Akt/mTOR and Nrf2/Keap 1 signaling. Our study demonstrated that baicalein enhanced DDP sensitivity of SGC-7901/DDP gastric cancer cells by inducing apoptosis and autophagy via Akt/mTOR and Nrf2/Keap 1 pathway.

Towards precision oncology for HER2 blockade in gastroesophageal adenocarcinoma

Gastroesophageal adenocarcinoma (GEA) represents a very heterogeneous disease and patients in advanced stages have a very poor prognosis. Although several molecular classifications have been proposed, precision medicine for HER2-amplified GEA patients still represents a challenge. Despite improvement in clinical outcomes obtained by adding trastuzumab to first-line platinum-based chemotherapy, no other anti-HER2 agents used first-line or beyond progression have demonstrated any benefit. Several factors contribute to this failure. Among them, variable HER2 amplification assessment, tumour heterogeneity, molecular mechanisms of resistance and microenvironmental factors could limit the effectiveness of anti-HER2 blockade. Identifying the factors responsible for both primary and acquired resistance is a priority for providing an improved, personalised approach. In this review, we examine current treatments for HER2-amplified GEA, their potential mechanisms of resistance and the ways to overcome them, investigating the most relevant translational studies with anti-HER2 agents in GEA, as well as novel agents under development in this field.

Combination Use of Tegafur and Apatinib as First-Line Therapy in Treatment of Advanced Gastric Cancer: A Single-Blinded Randomized Study

Objective

To investigate the efficacy and safety of the combination use of tegafur and apatinib as a first-line therapy strategy in advanced gastric cancer (GC).

Methods

The present study included a total of 62 advanced GC patients. The patients were randomized into the combined group (treated with both tegafur and apatinib) and the control group (treated with only tegafur). Treatment efficacy, KPS score, nutrition condition, and progression-free survival time (PFS) were recorded.

Results

Both the response and disease control rates were significantly higher in the combined group. The PFS time was remarkably higher and the KPS score was significantly reduced in the combined group after treatment. After treatment, both groups showed significantly increased nutrition risk, but the rates of patients with nutrition risk or innutrition were remarkably higher in the combined group. The ADR rates were also significantly higher in the combined group.

Conclusion

The combination use could achieve good efficacy and prolong patients' PFS time; however, apatinib also reduced the patients' quality of life and enhanced the nutrition risk and adverse drug reactions.

A systematical comparison of anti-angiogenesis and anti-cancer efficacy of ramucirumab, apatinib, regorafenib and cabozantinib in zebrafish model

AIMS

Gastric cancer (GC) is one of the most common malignant tumors in the world. Anti-angiogenic therapy is a useful strategy for the treatment of advanced GC. This study was aimed to systemically compare the anti-angiogenesis, anti-cancer efficacy, as well as the safety of four known anti-angiogenic drugs, namely ramucirumab, apatinib, regorafenib and cabozantinib.

MAIN METHODS

Anti-angiogenic effect was evaluated for the intersegmental vessels (ISVs) and subintestinal veins (SIVs) formation in the Tg (fli-1: EGFP) zebrafish embryos. Anti-cancer efficacy was tested for the in vivo cell proliferation in cell line derived tumor xenograft (CDX) model based on Tg (fli-1: EGFP) zebrafish embryos.

KEY FINDINGS

All four drugs exhibited anti-angiogenic abilities and tumor inhibition effects in fli-1: EGFP transgenic zebrafish. Using zebrafish xenografted model, we found that effectiveness of ramucirumab in anti-GC-proliferation is better than apatinib, regorafenib and cabozantinib. The combination of anti-angiogenic drugs and cisplatin showed no significant benefit in tumors. Meanwhile, toxicity assay showed that all tested anti-angiogenic drugs could cause cardiovascular-related side effects. The therapeutic index (LD50/ED50) of cabozantinib is higher than apatinib and regorafenib, suggesting a potential as an anti-GC drug.

SIGNIFICANCE

The comparison of GC-related anti-angiogenic drugs was first reported. It was found that cabozantinib had a potential as an anti-GC drug. Zebrafish model was an ideal animal model for the research of anti-angiogenic behaviors.

Model-based analysis of response and resistance factors of cetuximab treatment in gastric cancer cell lines

Targeted cancer therapies are powerful alternatives to chemotherapies or can be used complementary to these. Yet, the response to targeted treatments depends on a variety of factors, including mutations and expression levels, and therefore their outcome is difficult to predict. Here, we develop a mechanistic model of gastric cancer to study response and resistance factors for cetuximab treatment. The model captures the EGFR, ERK and AKT signaling pathways in two gastric cancer cell lines with different mutation patterns. We train the model using a comprehensive selection of time and dose response measurements, and provide an assessment of parameter and prediction uncertainties. We demonstrate that the proposed model facilitates the identification of causal differences between the cell lines. Furthermore, our study shows that the model provides predictions for the responses to different perturbations, such as knockdown and knockout experiments. Among other results, the model predicted the effect of MET mutations on cetuximab sensitivity. These predictive capabilities render the model a basis for the assessment of gastric cancer signaling and possibly for the development and discovery of predictive biomarkers.

Unraveling the causal differences between drug responders and non-responders is an important challenge. The information can help to understand molecular mechanisms and to guide the selection and design of targeted therapies. Here, we approach this problem for cetuximab treatment for gastric cancer using mechanistic mathematical modeling. The proposed model describes responder and non-responder gastric cancer cell lines and can predict the response in several validation experiments. Our analysis provides a differentiated view on mutations and explains, for instance, the relevance of MET mutations and the insignificance of PIK3CA mutation in the considered cell lines. The model might potentially provide the basis for understanding the recent failure of several clinical studies.

Deregulated expression of Elastin Microfibril Interfacer 2 (EMILIN2) in gastric cancer affects tumor growth and angiogenesis

Gastric cancer is a frequent human tumor and often a lethal disease. Targeted therapy for gastric carcinomas is far behind vis-à-vis other solid tumors, primarily because of the paucity of cancer-driving mutations that could be efficiently and specifically targeted by current therapy. Thus, there is a need to discover actionable pathways/proteins and new diagnostic and prognostic biomarkers. In this study, we explored the role of the extracellular matrix glycoprotein EMILIN2, Elastin Microfibril Interfacer 2, in a cohort of gastric cancer patients. We discovered that EMILIN2 expression was consistently suppressed in gastric cancer and high expression levels of this glycoprotein were linked to abnormal vascular density. Furthermore, we found that EMILIN2 had a dual effect on gastric carcinoma cells: on one hand, it decreased tumor cell proliferation by triggering apoptosis, and on the other hand, it evoked the production of a number of cytokines involved in angiogenesis and inflammation, such as IL-8. Collectively, our findings posit EMILIN2 as an important onco-regulator exerting pleiotropic effects on the gastric cancer microenvironment.

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EMILIN2 is localized in the gastric lamina propria and its expression is down-regulated in gastric cancer.

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High levels of EMILIN2 associate with elevated vascular density.

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EMILIN2 impairs the proliferation of gastric cancer cells by evoking apoptosis.

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Surprisingly, EMILIN2 triggers the expression of pro-angiogenic and pro-inflammatory cytokines.

Experimental Study on the Effect of a Weifufang on Human Gastric Adenocarcinoma Cell Line BGC-823 Xenografts and PTEN Gene Expression in Nude Mice

Background: This study aims at investigating the effect of the Weifufang, an effective prescription for the treatment of gastric cancer developed by the Traditional Chinese Medicine (TCM)/Combination of TCM and Western Medicine Department of the Hunan Cancer Hospital, on gastric cancer xenografts in nude mice and its effect on the PTEN gene; it also aims at exploring the possible tumor suppression mechanism. Methods: Nude mice with xenografts were treated with different concentrations of the Weifufang for 2 weeks, and changes in tumor volume were observed. The histopathology of the tumor was detected by hematoxylin and eosin staining; PTEN gene expression in tumor tissues was detected by immunohistochemistry (IHC) and western blot. Results: After 2 weeks of treatment, tumor inhibition rates in the 5-flourouracil (5-FU) group, and in the Weifufang low-, middle-, and high-dose groups were 30.67%, 19%, 49.52%, and 29.36%, respectively. The IOD of the PTEN gene was detected by IHC. The values in the water group, the 5-FU group, and the Weifufang low-, middle-, and high-dose groups were 0.013 ± 0.004, 0.085 ± 0.062, 0.041 ± 0.024, 0.128 ± 0.032, and 0.061 ± 0.052, respectively. Except for the 5-FU group, the differences between the gastric compound middle dose-group and the other groups were statistically significant (p < 0.05). Results of PTEN expression detection by western blot: The expression levels in the water group, 5-FU group, and the Weifufang low-, middle-, and high-dose groups were 0.2240 ± 0.0172, 0.4200 ± 0.0228, 0.2760 ± 0.0163, 0.3840 ± 0.0133, and 0.3040 ± 0.0211, respectively. Except for the 5-FU group, differences between the Weifufang middle-dose group and the other groups were statistically significant (p < 0.05). Conclusion: The Weifufang may inhibit the growth of gastric cancer xenografts by upregulating PTEN gene expression. The middle-dose group had the best effect.

Analysis of the Effect of Increased α2,3-Sialylation on RTK Activation in MKN45 Gastric Cancer Spheroids Treated with Crizotinib

In the scenario of personalized medicine, targeted therapies are currently the focus of cancer drug development. These drugs can block the growth and spread of tumor cells by interfering with key molecules involved in malignancy, such as receptor tyrosine kinases (RTKs). MET and Recepteur d'Origine Nantais (RON), which are RTKs frequently overactivated in gastric cancer, are glycoprotein receptors whose activation have been shown to be modulated by the cellular glycosylation. In this work, we address the role of sialylation in gastric cancer therapy using an innovative 3D high-throughput cell culture methodology that mimics better the in vivo tumor features. We evaluate the response to targeted treatment of glycoengineered gastric cancer cell models overexpressing the sialyltransferases ST3GAL4 or ST3GAL6 by subjecting 3D spheroids to the tyrosine kinase inhibitor crizotinib. We show here that 3D spheroids of ST3GAL4 or ST3GAL6 overexpressing MKN45 gastric cancer cells are less affected by the inhibitor. In addition, we disclose a potential compensatory pathway via activation of the Insulin Receptor upon crizotinib treatment. Our results suggest that cell sialylation, in addition of being involved in tumor progression, could play a critical role in the response to tyrosine kinase inhibitors in gastric cancer.

Tumor-associated macrophages regulate gastric cancer cell invasion and metastasis through TGFβ2/NF-κB/Kindlin-2 axis

Objective

Recent studies have shown that tumor-associated macrophages (TAMs) play an important role in cancer invasion and metastasis. Our previous studies have reported that TAMs promote the invasion and metastasis of gastric cancer (GC) cells through the Kindlin-2 pathway. However, the mechanism needs to be clarified.

Methods

THP-1 monocytes were induced by PMA/interleukin (IL)-4/IL-13 to establish an efficient TAM model in vitro and M2 macrophages were isolated via flow cytometry. A dual luciferase reporter system and chromatin immunoprecipitation (ChIP) assay were used to investigate the mechanism of transforming growth factor β2 (TGFβ2) regulating Kindlin-2 expression. Immunohistochemistry was used to study the relationships among TAM infiltration in human GC tissues, Kindlin-2 protein expression, clinicopathological parameters and prognosis in human GC tissues. A nude mouse oncogenesis model was used to verify the invasion and metastasis mechanisms in vivo.

Results

We found that Kindlin-2 expression was upregulated at both mRNA and protein levels in GC cells cocultured with TAMs, associated with higher invasion rate. Kindlin-2 knockdown reduced the invasion rate of GC cells under coculture condition. TGFβ2 secreted by TAMs regulated the expression of Kindlin-2 through the transcription factor NF-кB. TAMs thus participated in the progression of GC through the TGFβ2/NF-κB/Kindlin-2 axis. Kindlin-2 expression and TAM infiltration were significantly positively correlated with TNM stage, and patients with high Kindlin-2 expression had significantly poorer overall survival than patients with low Kindlin-2 expression. Furthermore, Kindlin-2 promoted the invasion of GC cells in vivo.

Conclusions

This study elucidates the mechanism of TAMs participating in GC cell invasion and metastasis through the TGFβ2/NF-κB/Kindlin-2 axis, providing a possibility for new treatment options and approaches.

Clinical management patterns of advanced and metastatic gastro-oesophageal carcinoma after fluoropyrimidine/platinum treatment in France, Germany, Spain and the United Kingdom

OBJECTIVE

To describe treatment patterns and resource utilisation in France, Germany, Spain and the United Kingdom (UK) in patients with unresectable locally advanced and/or metastatic gastro-oesophageal adenocarcinoma (GEA), who failed first-line fluoropyrimidine/platinum treatment.

METHODS

Treating physicians completed a web-based chart review (2013-2015). Eligible patients were ≥ 18 years old; had unresectable locally advanced and/or metastatic gastric adenocarcinoma including the gastro-oesophageal junction; received first-line fluoropyrimidine/platinum-based therapy; and had ≥ 3 months of follow-up after first-line discontinuation. Data were summarised descriptively for each country.

RESULTS

There were n = 201 patients in France, n = 202 in Germany, n = 208 in Spain and n = 200 in the UK whose charts were reviewed. Percentages of patients receiving second-line therapy were 55% (France), 48% (Germany), 54% (Spain) and 29% (UK). At the start of second-line therapy, most patients had an ECOG performance status of 1 (range 0-3). Second-line therapy was primarily monotherapy, but agents used varied within and across countries. Supportive care use and resource utilisation were frequent whether receiving additional therapy or not; >60% patients had clinic visits unrelated to chemotherapy administration, and > 30% has ≥ 1 hospital admission.

CONCLUSIONS

For the time of study, established GEA treatment guidelines were generally followed. However, therapies varied widely in the second-line setting.

M-phase phosphoprotein 8 promotes gastric cancer growth and metastasis via p53/Bcl-2 and EMT-related signaling pathways

BACKGROUND

The main issue of this study is to demonstrate whether M-phase phosphoprotein 8 (MPP8) affect gastric tumor growth and metastasis.

METHODS

Retrospective study was proceeded in 280 patients' surgical specimens with different disease stages. Loss-of-function assays, including 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide, flow cytometry, and transwell assays were performed to evaluate the biological function of MPP8 in gastric cancer cells. Apoptosis and metastasis relative biomarkers were measured by quantitative real-time polymerase chain reaction and Western blot analysis.

RESULTS

Compared with normal adjacent tissues, obviously elevated MPP8 expression was found in gastric cancer tissues. Elevated MPP8 expression was associated with male sex (vs female sex), intermediate differentiation (vs poorly differentiated cancer), and later stage (vs earlier stage). Furthermore, MPP8 overexpression in tumor tissues was marginally associated with a poor prognosis, with a significant relationship between MPP8 overexpression and prognosis among patients with poorly differentiated gastric cancer. Inhibition of MPP8 in these cells significantly suppressed proliferation and colony formation, promoted apoptosis, and repressed invasion. Furthermore, silencing of MPP8 remarkably increased apoptosis-related proteins (p53, Bax, and PARP) expression, but downregulated Bcl-2 expression. Silencing of MPP8 also decreased the expression of metastasis pathway-related proteins (N-cadherin and vimentin), and as well as the levels of anti-oncogene ZEB1, MET, and KRAS mRNA.

CONCLUSION

Our findings demonstrated that MPP8 might be an oncogene by positively regulating gastric cancer cell function through the p53/Bcl-2 and epithelial to mesenchymal transition-related signaling pathways.

Dose-finding study of modified FLOT (mFLOT) regimen as first-line treatment in Chinese patients with metastatic adenocarcinoma of stomach

PURPOSE

To determine the maximum tolerated dose (MTD) and recommended dose (RD) of modified FLOT regimen (fluorouracil plus leucovorin, oxaliplatin and docetaxel) for treating Chinese patients with metastatic adenocarcinoma of stomach.

METHODS

Chinese patients with untreated advanced or metastatic stomach adenocarcinoma were enrolled. Docetaxel (D), oxaliplatin (O) and leucovorin were administrated intravenously on day 1. Fluorouracil (F) was administrated continuous intravenously on day 1 for 48 h. The treatment was repeated every 2 weeks. The start doses of docetaxel and oxaliplatin were 40 mg/m² and 65 mg/m², respectively. Dose escalation followed a 3 + 3 design. Total 6 dose levels were set to determine the MTD and RD. Fluorouracil and leucovorin were given as fix doses at 2200 mg/m² and 200 mg/m², respectively. Adverse events that occurred in the first 2 cycles were recorded to determine dose-limiting toxicity (DLT). The primary endpoints were MTD and RD determination.

RESULTS

A total of 18 patients were treated in 5 dose levels. DTL occurred in one patient of level 4 (grade 3 hypophosphatemia). Other 3 patients were enrolled in level 4 and no DLTs were observed. In level 5, 2 patients suffered grade 4 neutropenia after first cycle of treatment and were defined as DLTs. Therefore, level 5 (D/O/F: 50/75/2200 mg/m²) was defined as MTD and level 4 (D/O/F: 45/75/2200 mg/m²) was defined as RD. Common adverse events in first two cycles were nausea, anorexia, leukopenia, neutropenia and anemia. For 16 patients assessable for tumor response, 7 patients had partial response (43.7%) and 5 experienced stable disease. Disease control rate were 75% (12/16). Two patients underwent conversion operation after 6 cycles of treatment. One pathological complete response (case in level 3) and one pathological partial response (case in level 2) were observed. Median progression-free survival was 4.4 months (95% CI 2.9-5.9 months) in 14 patients.

CONCLUSIONS

The RD of modified FLOT regimen in Chinese patients with advanced gastric cancer was docetaxel 45 mg/m², oxaliplatin 75 mg/m², leucovorin 200 mg/m² and fluorouracil 2200 mg/m² on day 1 of every 14-day cycle. Its efficacy will be assessed by further phase II study.

circZNF609 promotes the proliferation and migration of gastric cancer by sponging miR-483-3p and regulating CDK6

Objective

To explore the regulatory effects of circZNF609 on proliferative and migratory capacities of gastric cancer (GC) and its underlying mechanism.

Methods

Expression level of circZNF609, CDK6 and miR-483-3p in GC tissues and cells were detected qRT-PCR verification. CCK-8 and transwell assay were conducted the cell viability and migratory capacities of GC cells. Dual luciferase assay was enrolled to confirm the interaction among circZNF609, CDK6 and miR-483-3p. Western blot was used to detect the protein level of CDK6.

Results

Expression levels of circZNF609 were higher in GC patients by qRT-PCR.GC patients with higher expression of circZNF609 were expected to have a higher TNM stage and lower 5-year survival than those with lower expression. ROC curves showed a well diagnostic value of circZNF609 in GC. Treatment of RNase R in GC cells downregulated the expression of ZNF609, whereas circZNF609 expression did not change. Furthermore, cytoplasmic expression of circZNF609 was higher than those of nuclear expression. Besides, biological experiments indicated that overexpression of circZNF609 promoted the proliferative and migratory capacities of GC cells. To demonstrate the underlying mechanism of circZNF609, we found that circZNF609 bound to miR-483-3p, which presented a lower expression in GC tissues than that of paracancerous tissues. Both circZNF609 and miR-483-3p could bind to Ago2, suggesting that circZNF609 may act as a sponge of miR-483-3p. In addition, the effect of overexpressed circZNF609 on cellular behaviors of GC cells were partly reversed by overexpression of miR-483-3p. Bioinformatics suggested that CDK6 has a potential binding site with miR-483-3p. The expression of CDK6 markedly increased in GC tissues and cells, which was negatively correlated with miR-483-3p expression. Dual-luciferase reporter gene results indicated that miR-483-3p could bind to the 3’-UTR of CDK6. Moreover, miR-483-3p downregulated CDK6 at both mRNA and protein levels. Overexpression of miR-483-3p inhibited proliferative and migratory capacities of GC cells, which were reversed by CDK6 overexpression.

Conclusion

In summary, the expression of circZNF609 is upregulated in GC. CircZNF609 can be used as the sponge of miR-483-3p to regulate the expression level of CDK6, thus participating in the progression of GC by regulating the proliferative and migratory capacities of GC cells.

A multicentric Spanish study on the characteristics and survival of gastric adenocarcinoma under the age of 60

INTRODUCTION

In Europe, gastric adenocarcinoma (GADC) is commonly regarded as a disease of the elderly. This study aims to assess the proportion, characteristics, and survival of patients diagnosed with GADC under the age of 60.

MATERIALS AND METHODS

This is a retrospective, multicentric, and analytical study conducted at four tertiary Spanish hospitals. All patients diagnosed with GADC between 2008 and 2015 were included. Demographic, clinical, endoscopic, histologic, and survival data were retrieved. A multivariate analysis was performed to compare GADC in young (age≤60 years) and elderly patients.

RESULTS

A total of 1374 patients with GADC were included. The mean age was 74 years (SD:11.1); 62.2% were males. There were 177 patients under the age of 60 (12.9%, 95% CI: 11.2-14.8%). GADC was frequently encountered as a metastatic disease in both young and elderly patients (Stage IV: 45.7% and 41%, respectively). In the multivariate analysis, alcohol abuse, ASA functional status I-II, diffuse subtype, neoadjuvant, and palliative therapy were independently associated (P<0.05) with age ≤60 years. No differences were found in 2-year survival (GADC ≤60: 39% vs. 35%, P=0.45). Curative-intent surgery, TNM stage I-II, body mass index<30kg/m², and better functional status at diagnosis were independent predictors of survival in GADC under the age of 60.

CONCLUSIONS

One out of eight cases of GADC were diagnosed under the age of 60. Metastatic disease was frequent at diagnosis and overall survival was poor regardless of age. Factors associated with localized disease correlated with improved survival in younger patients. Our results underline the need for early diagnosis strategies in our country.

Poor outcome for patients with gastric cancer and lung metastases treated with ramucirumab and paclitaxel

The aim of this report is to investigate the activity of ramucirumab in combination with paclitaxel in patients with metastatic gastric cancer (GC) and lung metastases. We retrospectively reviewed clinical data from patients with GC treated in second line with ramucirumab and paclitaxel according to the presence or not of lung metastases. Thirty-one patients were eligible. Five (16.1%) patients had lung metastases. The median progression-free survival was 156 days in patients without lung metastases compared with 54 days in patients with lung metastases. The median survival also showed a trend in favour of patients without lung metastases. Despite the small number of patients and the retrospective nature of the data, our analysis showed relatively poor efficacy of ramucirumab plus paclitaxel as a second-line treatment in patients with lung metastases from GC. Further studies are required to evaluate novel treatments in this subset of patients.

Adapting and Surviving: Intra and Extra-Cellular Remodeling in Drug-Resistant Gastric Cancer Cells

Despite the significant recent advances in clinical practice, gastric cancer (GC) represents a leading cause of cancer-related deaths in the world. In fact, occurrence of chemo-resistance still remains a daunting hindrance to effectiveness of the current approach to GC therapy. There is accumulating evidence that a plethora of cellular and molecular factors is implicated in drug-induced phenotypical switching of GC cells. Among them, epithelial-mesenchymal transition (EMT), autophagy, drug detoxification, DNA damage response and drug target alterations, have been reported as major determinants. Intriguingly, resistant GC phenotype may be the result of GC cell-induced tumor microenvironment (TME) remodeling, which is currently emerging as a key player in promoting drug resistance and overcoming cytotoxic effects of drugs. In this review, we discuss the possible mechanisms of drug resistance and their involvement in determining current GC therapies failure.

MicroRNA‑140 suppresses Helicobacter pylori‑positive gastric cancer growth by enhancing the antitumor immune response

Immune checkpoint blockade is a promising therapeutic strategy against various human malignancies. MicroRNAs (miRNAs/miRs) regulate gene expression, by repressing mRNA translation or promoting its degradation. The aim of the current study was to investigate the role and molecular mechanisms of miR‑140 in Helicobacter pylori (Hp)‑associated gastric cancer, and to examine its relationship with immune function in gastric cancer. Gastritis tissue samples from gastritis patients, and gastric cancer tissue samples from gastric cancer patients were collected for miR‑140 expression detection. miR‑140 expression was detected using reverse transcription‑quantitative polymerase chain reaction, and protein expression was measured by western blotting. TargetScan and dual luciferase reporter assays were used to reveal the association between miR‑140 and programmed cell death‑ligand 1 (PD‑L1). BGC823 cell proliferation was detected by MTT assays. Ex vivo immune analysis by flow cytometry and ELISA were used to analyze immune function. It was demonstrated that miR‑140 expression was significantly reduced in Hp‑positive gastric cancer. PD‑L1 was confirmed as a direct target of miR‑140 in gastric cancer cells. In addition, PD‑L1 expression was significantly increased in Hp‑positive gastric cancer. Overexpression of miR‑140 significantly suppressed gastric cancer cell proliferation through regulating PD‑L1 expression. In vivo experiments also revealed that miR‑140 markedly repressed tumor growth in the C57BL/6 mice. Furthermore, it was determined that the tumor‑suppressive role of miR‑140 in gastric cancer was associated with increased cytotoxic CD8+ T cell and reduced myeloid‑derived suppressive and regulatory T cell infiltration. miR‑140 significantly prevented mammalian target of rapamycin signaling in gastric cancer cells. Notably, these miR‑140 overexpression‑induced alterations were inhibited by PD‑L1 plasmid. These findings indicated that miR‑140 exerted an anti‑gastric cancer effect by targeting immune checkpoint molecule PD‑L1. Thus, miR‑140 may be a promising and novel immunotherapeutic target for gastric cancer treatment.