Gastric cancer

Prediction Model of Tumor Regression Grade for Advanced Gastric Cancer After Preoperative Chemotherapy

Background

Preoperative chemotherapy (PCT) has been considered an important treatment for advanced gastric cancer (AGC). The tumor regression grade (TRG) system is an effective tool for the assessment of patient responses to PCT. Pathological complete response (TRG = 0) of the primary tumor is an excellent predictor of better prognosis. However, which patients could achieve pathological complete response (TRG = 0) after chemotherapy is still unknown. The study aimed to find predictors of TRG = 0 in AGC.

Methods

A total of 304 patients with advanced gastric cancer from July 2009 to November 2018 were enrolled retrospectively. All patients were randomly assigned (2:1) to training and internal validation groups. In addition, 124 AGC patients receiving PCT from December 2018 to June 2020 were included prospectively in the external validation cohort. A prediction model for TRG = 0 was established based on four predictors in the training group and was validated in the internal and external validation groups.

Results

Through univariate and multivariate analyses, we found that CA199, CA724, tumor differentiation and short axis of the largest regional lymph node (LNmax) were independent predictors of TRG = 0. Based on the four predictors, we established a prediction model for TRG = 0. The AUC values of the prediction model in the training, internal and external validation groups were 0.84, 0.73 and 0.82, respectively.

Conclusions

We found that CA199, CA724, tumor differentiation and LNmax were associated with pathological response in advanced gastric cancer. The prediction model could provide guidance for clinical work.

circATP2B1 Promotes Aerobic Glycolysis in Gastric Cancer Cells Through Regulation of the miR-326 Gene Cluster

The discovery of circular RNA (circRNA) enormously complimented the repertoire of traditional gene expression theory. As a type of endogenous noncoding RNA, circRNA participates in the occurrence of many kinds of tumors in addition to regulating their development. The Warburg effect (aerobic glycolysis is taken with priority for cancer cells instead of oxidative phosphorylation) is one of the most important factors involved in the excessive proliferation of gastric cancer cells. Our data showed that circRNA circATP2B1 (also called hsa_circ_000826) was overexpressed in gastric cancer tissues instead of linear ATP2B1 mRNA, and it promoted aerobic glycolysis in gastric cancer cells. Bioinformatic Gene Ontology analysis showed that the potential downstream targets of circATP2B1 include the microRNA miR-326 gene cluster (miR-326-3p/miR-330-5p), which is functionally focused on cell growth and metabolic processes. The expressions of miR-326-3p/miR-330-5p were downregulated in gastric cancer, and circATP2B1 functionally targeted miR-326-3p/miR-330-5p in an RNA-induced silencing complex (RISC) dependent manner. Dual-luciferase reporter assays demonstrated that pyruvate kinase M2 (PKM2) was one of the targets of miR-326-3p/miR-330-5p. As a rate-limiting enzyme in the aerobic glycolytic pathway, PKM2 accelerated gastric cancer cells' glucose uptake and increased cell viability. Taken together, circATP2B1 captured miR-326-3p/miR-330-5p and decreased the suppression of PKM2 by miR-326-3p/miR-330-5p, thus aiding the aerobic glycolysis and proliferation of gastric cancer cells. This study identified a novel molecular pathway in gastric cancer that may provide more targets for reversing cancer metabolic reprogramming, as well as a potential strategy for targeted therapy of gastric cancer.

CSF1R is a Prognostic Biomarker and Correlated with Immune Cell Infiltration in the Gastric Cancer Microenvironment

Purpose

The tumor microenvironment (TME) plays a crucial role in the progression and prognosis of gastric cancer (GC). This study investigated TME-associated genes and explored their roles in the GC microenvironment.

Methods

A total of 330 GC samples were extracted from TCGA. ESTIMATE and CIBERSORT algorithms were utilized to evaluate the stromal and immune scores of GC samples and the fraction of 22 immune cells infiltrated in the TME. Then, the TME-related differentially expressed genes (DEGs) were determined through integrative analysis. Protein-protein interaction (PPI) network and Cox regression analysis were conducted to analyze DEGs, and CSF1R was determined as the most crucial gene. We further probed the role of CSF1R in the GC microenvironment and evaluated the prognostic value of CSF1R.

Results

We identified 560 TME-related DEGs and found CSF1R associated with the development and prognosis of GC. Further analysis showed that CSF1R was involved in immune-related signaling pathways. Furthermore, CIBERSORT analysis revealed that CSF1R expression correlated with several kinds of infiltrating immune cells, including tumor-associated macrophages (TAMs), B cells, NK cells, neutrophils, eosinophils, T cells, dendritic cells, and so on.

Conclusion

In summary, CSF1R might take part in the modulation of immune-active status in the GC microenvironment and could be a promising biomarker for GC therapy and prognosis.

A Panel of Five-lncRNA Signature as a Potential Biomarker for Predicting Survival in Gastric and Thoracic Cancers

Dysfunctional long non-coding RNAs (lncRNAs) have been found to have carcinogenic and/or tumor inhibitory effects in the development and progression of cancer, suggesting their potential as new independent biomarkers for cancer diagnosis and prognosis. The exploration of the relationship between lncRNAs and the overall survival (OS) of different cancers opens up new prospects for tumor diagnosis and treatment. In this study, we established a five-lncRNA signature and explored its prognostic efficiency in gastric cancer (GC) and several thoracic malignancies, including breast invasive carcinoma (BRCA), esophageal carcinoma, lung adenocarcinoma, lung squamous cell carcinoma (LUSC), and thymoma (THYM). Cox regression analysis and lasso regression were used to evaluate the relationship between lncRNA expression and survival in different cancer datasets from GEO and TCGA. Kaplan-Meier survival curves indicated that risk scores characterized by a five-lncRNA signature were significantly associated with the OS of GC, BRCA, LUSC, and THYM patients. Functional enrichment analysis showed that these five lncRNAs are involved in known biological pathways related to cancer pathology. In conclusion, the five-lncRNA signature can be used as a prognostic marker to promote the diagnosis and treatment of GC and thymic malignancies.

Role of the nervous system in cancers: a review

Nerves are important pathological elements of the microenvironment of tumors, including those in pancreatic, colon and rectal, prostate, head and neck, and breast cancers. Recent studies have associated perineural invasion with tumor progression and poor outcomes. In turn, tumors drive the reprogramming of neurons to recruit new nerve fibers. Therefore, the crosstalk between nerves and tumors is the hot topic and trend in current cancer investigations. Herein, we reviewed recent studies presenting direct supporting evidences for a better understanding of nerve-tumor interactions.

Identification and validation of the prognostic value of cyclic GMP-AMP synthase-stimulator of interferon (cGAS-STING) related genes in gastric cancer

The cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway play a significant role in the production of inflammatory cytokines and type I interferons. This study aims to develop a cGAS-STING pathway-related genes (CSRs) prediction model to predict prognosis in gastric cancer (GC). In the present study, we used The Cancer Genome Atlas (TCGA), Gene Expression Omnibus databases (GEO), CIBERSORT and Tumor Immune Estimation Resource databases (TIMER). The risk model based on five hub genes (IFNB1, IFNA4, IL6, NFKB2, and TRIM25) was constructed to predict the overall survival (OS) of GC. Further univariate Cox regression (URC) and multivariate Cox regression (MCR) analyses revealed that this risk scoring model was an independent factor. The results were verified by GEO external validation set. Multiple immune pathways were assessed by Gene Set Enrichment Analysis (GSEA). TIMER analysis demonstrated that risk score strongly correlated with Macrophage, B cells and CD8 + T cells infiltration. In addition, through ‘CIBERSORT’ package, the higher levels of infiltration of T cell follicular assistance (P = 0.011), NK cells-activated (P = 0.034), and Dendritic cells resting (P = 0.033) exhibited in high-risk group. Kaplan–Meier (K-M) survival analysis illustrated T cells CD4 memory resting and T cells follicular helper infiltration correlated with overall survival (OS) of GC patients in TCGA and GEO databases. Altogether, the risk score model can be conveniently used to predict prognosis. The immunocyte infiltration analysis provided a novel horizon for monitoring the status of the GC immune microenvironment.

Abbreviations:TCGA: The Cancer Genome Atlas databases; GEO: Gene Expression Omnibus databases; GC: Gastric cancer; CSRs: cGAS-STING pathway-related genes; DECSRs: Differential expressed cGAS-STING pathway-related genes; PCSRs: Prognosis related cGAS-STING pathway genes; URC: Univariate Cox regression analyses; MCR: Multivariate Cox regression analyses GSEA: Gene set enrichment analysis; TIIC: Tumor-infiltrating immune cell.

ADAMTS19 Suppresses Cell Migration and Invasion by Targeting S100A16 via the NF-κB Pathway in Human Gastric Cancer

A Disintegrin and Metalloproteinase with Thrombospondin motifs 19 (ADAMTS19) has been reported to participate in the pathogenesis of solid cancers. However, its role in gastric cancer (GC) remains undocumented. Using immunohistochemistry (IHC) staining and quantitative real-time polymerase chain reaction (qRT-PCR) on GC tissues and adjacent normal tissues, we found that ADAMTS19 was downregulated in GC tissues (IHC: p < 0.001; qRT-PCR: p = 0.017). Further investigation revealed that ADAMTS19 correlated with distant metastasis (p = 0.008) and perineural invasion (p = 0.018) and that patients with low ADAMTS19 had worse overall survival (p = 0.021). Gain- and loss-of-function assays showed that ADAMTS19 suppressed cell migration and invasion in vitro. Using bioinformatics analysis and co-immunoprecipitation, immunofluorescence, and dual-luciferase reporter gene assays, we confirmed that ADAMTS19 binds with cytoplasm P65, decreasing the nucleus phosphorylation of P65, a crucial transcription factor in the nuclear factor kappa-B (NF-κB) pathway, thereby downregulating S100 calcium-binding protein A16 (S100A16) expression. S100A16 acted as the downstream of ADAMTS19, reversing the suppression of cell migration and invasion by ADAMTS19 in vitro. A combination of ADAMTS19 and S100A16 expression provided the optimal prognostic indicator for GC. Patients with ADAMTS19^high-S100A16^low had better overall survival than ADAMTS19^low-S100A16^high patients (p = 0.006). These results suggest that ADAMTS19 suppresses cell migration and invasion by targeting S100A16 via the NF-κB pathway and that ADAMTS19 and S100A16 are potential metastasis and survival biomarkers for GC.

Effect and mechanisms of LINC00152 knockdown on chemotherapy resistance in mitomycin-resistant gastric cancer NCI-N87/MMC cells

BACKGROUND

Long intergenic noncoding RNA 152 (LINC00152) is highly expressed in gastric cancer tissues, and it can promote the proliferation, migration, and invasion of gastric cancer cells. However, the effects and mechanisms of LINC00152 on chemotherapy resistance in gastric cancer are not clear.

AIM

To explore the effects and related mechanisms of LINC00152 on chemotherapy resistance in human gastric cancer cell line NCI-N87.

METHODS

The expression of LINC00152 in human gastric cancer cell line NCI-N87 and mitomycin (MMC) resistant cell line NCI-N87/MMC was detected by real-time PCR. After the expression of LINC00152 in NCI-N87/MMC cells was knocked down by RNA interference method, the sensitivity of cells to MMC and cisplatin was measured by MTT assay, cell apoptosis was detected by flow cytometry, and the protein expression levels of Bcl-2, Bax, Caspase 3, and cleaved Caspase 3 were determined by Western Blot. Furthermore, the expression levels of MDR1/P-gp, Mgr1-Ag, and MRP were evaluated by real-time PCR and Western Blot.

RESULTS

The expression level of INC00152 in NCI-N87/MMC cells was significantly higher than that in maternal NCI-N87 cells. LINC00152 knockdown induced apoptosis and increased sensitivity to MMC and cisplatin in NCI-N87/MMC cells. LINC00152 knockdown inhibited the expression of Bcl-2 protein in NCI-N87/MMC cells, but promoted the expression of Bax protein and the activation of Caspase 3. Furthermore, LINC00152 knockdown down-regulated the mRNA and protein expression of MDR1, Mgr1-Ag, and MRP in NCI-N87/MMC cells.

CONCLUSION

Down-regulation of LINC00152 in NCI-N87/MMC cells can increase the sensitivity of cells to MMC and cisplatin, and the mechanisms may be related to the promotion of cell apoptosis by regulating apoptotic-related factors, and down-regulation of MDR1, Mgr1-Ag, and MRP.

Long noncoding RNA GAS8-AS1: A novel biomarker in human diseases

Long non-coding RNAs (lncRNAs) represent a group of ncRNAs with more than 200 nucleotides. These RNAs can specifically regulate gene expression at both the transcriptional and the post-transcriptional levels, and increasing evidence indicates that they play vital roles in a variety of disease-related cellular processes. The lncRNA GAS8 antisense RNA 1 (GAS8-AS1, also known as C16orf3) is located in the second intron of GAS8 and has been reported to be both abnormally expressed in several diseases and closely correlated with many clinical characteristics. GAS8-AS1 has been shown to affect many biological functions, including cell proliferation, migration, invasiveness, and autophagy using several signaling pathways. In this review, we have summarized current studies on GAS8-AS1 roles in disease and discuss its potential clinical utility. GAS8-AS1 may be a promising biomarker for both diagnoses and prognoses, and a novel target for many disease therapies.

Tumor-Associated Macrophages and Inflammatory Microenvironment in Gastric Cancer: Novel Translational Implications

Gastric cancer (GC) represents the fifth most frequently diagnosed cancer worldwide, with a poor prognosis in patients with advanced disease despite many improvements in systemic treatments in the last decade. In fact, GC has shown resistance to several treatment options, and thus, notable efforts have been focused on the research and identification of novel therapeutic targets in this setting. The tumor microenvironment (TME) has emerged as a potential therapeutic target in several malignancies including GC, due to its pivotal role in cancer progression and drug resistance. Therefore, several agents and therapeutic strategies targeting the TME are currently under assessment in both preclinical and clinical studies. The present study provides an overview of available evidence of the inflammatory TME in GC, highlighting different types of tumor-associated cells and implications for future therapeutic strategies.

Clinical value of lncRNA CCAT1 in serum extracellular vesicles as a potential biomarker for gastric cancer

Long non-coding RNAs (lncRNAs) in extracellular vesicles (EVs) are considered to be novel non-invasive biomarkers for gastric cancer (GC). lncRNA colon cancer-associated transcript 1 (CCAT1) is aberrantly expressed in certain types of cancer. However, the role of EV lncRNA CCAT1 in patients with GC remains unclear. The current study aimed to assess the expression levels of lncRNA CCAT1 in the serum EVs of patients with GC and evaluate its potential clinical value. EVs were isolated from serum using a commercial kit and ultracentrifugation, and were identified by transmission electron microscopy, nanoparticle tracking analysis and western blotting. Serum EV lncRNA CCAT1 levels in patients with GC, chronic gastritis or atypical hyperplasia and healthy control subjects were detected by reverse transcription-quantitative PCR. Additionally, lncRNA CCAT1 was detected in GC and adjacent non-cancerous tissue samples. Serum EVs were successfully isolated and identified in all patients. The results revealed that serum EV lncRNA CCAT1 levels in patients with GC were significantly higher compared with those in healthy controls, patients with chronic gastritis or atypical hyperplasia (all P<0.05). Additionally, EV lncRNA CCAT1 expression levels were significantly different among various groups based on the depth of invasion, distant metastasis and the Tumor-Node-Metastasis stage. The area under the curve (AUC) value of EV lncRNA CCAT1 was 0.890 [95% confidence interval (CI), 0.826–0.937] with 79.6% sensitivity and 92.6% specificity. The combination of EV lncRNA CCAT1 and carcinoembryonic antibody produced an AUC value of 0.910 (95% CI, 0.849–0.951) with the sensitivity and specificity of 80.5 and 92.6%, respectively. In addition, lncRNA CCAT1 was determined to be stable in serum EVs. The expression levels of lncRNA CCAT1 in GC tissue were positively correlated with those in serum EVs, and high levels of lncRNA CCAT1 were associated with a low disease-free survival rate in patients with GC. The results of the present study demonstrated that serum EV lncRNA CCAT1 levels were upregulated in patients with GC compared with those healthy subjects and patients with other illnesses, and may therefore be used as a novel biomarker for this type of cancer.

Ceritinib increases sensitivity of AKT inhibitors to gastric cancer

Gastric cancer (GC), known for high morbidity and mortality, is poorly prognosed with traditional chemotherapy and biological agents. Current studies have found that over-activation of AKT is a common molecular characteristic in GC. Although the development of this targeted inhibitor has entered clinical phases, limited success is reported because of its compensatory signaling pathways. Here, we found that GC cell lines with high phosphorylation of AKT show different sensitivity to AKT inhibitors (AKTis), but a reduction of p-GSK3β related sensitivity of AKTis in GC cells. Besides, we revealed that Ceritinib exerted a strongly synergistic antitumor effect with AKT inhibitors both in vitro and in vivo. Obviously, Ceritinib improved the sensitivity of Capivasertib (AZD5363, AKTs) and Afuresertib (GSK2110183, AKTis) in gastric cancer cells, as illustrated by a significant reduction in the GC cell proliferation and enhanced apoptosis. The drug combination showed tumor regression in BALB/c (nu/nu) mouse MKN45 (Gastric cancer), tumor model. Also, the combination strategy indicated significantly low p-AKT levels due to AKTis compensation and reduced the levels of p-GSK3β in both GC cell lines and GC patient-derived cells. These findings may provide a novel combination strategy for gastric cancer treatment.

Predictors of Remission and Relapse of Diabetes after Conventional Gastrectomy for Gastric Cancer: Nationwide Population-Based Cohort Study

BACKGROUND

We investigated whether preoperative clinical parameters predict diabetes remission and relapse after conventional gastrectomy for cancer and whether postoperative weight changes influence diabetes remission and relapse.

STUDY DESIGN

This study included 5,150 patients with diabetes who underwent gastrectomy for cancer from 2004 to 2014. Diabetes remission was defined in 3 ways, according to postoperative antidiabetic medication and fasting plasma glucose (FPG) levels. Diabetes relapse was defined as reinitiating antidiabetic medication among patients in diabetes remission.

RESULTS

Six predictors (higher body mass index [BMI], total gastrectomy, younger age, FPG levels, number of oral hypoglycemic agents [OHAs], and no insulin use) of diabetes remission increased the likelihood of remission by >13-fold (odds ratio [OR], 13.67; 95% confidence interval [CI], 8.65‒19.11). Three factors (younger age, lower FPG levels, and use of only 1 OHA) predicted a 58% decreased likelihood of diabetes relapse (hazard ratio, 0.42; 95% CI 0.35‒0.48). The lowest interval of postoperative BMI decrease (<-20%) showed a >3-fold increased likelihood of diabetes remission than the highest interval (≥-5%; OR 3.14; 95% CI 2.08‒4.75), independent of baseline BMI.

CONCLUSIONS

Six variables (BMI, type of gastrectomy, age, FPG levels, number of OHAs used, and insulin use/non-use), and 3 variables (age, FPG levels, number of OHAs used) significantly predict diabetes remission and relapse after gastrectomy for cancer, respectively. Greater postoperative weight decrease may increase the likelihood of diabetes remission, independent of baseline weight. Our results may serve as a basis for the establishment of diabetes and weight management strategies after conventional gastrectomy for cancer.

Prognosis after surgery for gastric adenocarcinoma in the Swedish Gastric Cancer Surgery Study (SWEGASS)

BACKGROUND

Most studies examining prognostic factors after gastrectomy come from selected patients and non-Western populations. This nationwide population-based cohort study aims to identify prognostic factors after surgery for gastric adenocarcinoma in an unselected Western cohort.

METHODS

This study included 98% of patients who underwent gastrectomy for gastric adenocarcinoma in Sweden in 2006-2015, with follow-up through 2019. Data were collected from medical records and national registries. Exposures were sex, age, education, comorbidity, tumor sub-localization, tumor stage, calendar period, and pre-operative chemotherapy. Outcomes were 3-year all-cause and disease-specific mortality. Cox regression produced hazard ratios (HRs) with 95% confidence intervals (95% CIs), adjusted for the other study exposures.

RESULTS

Among all 2154 patients, 3-year all-cause mortality was 53.3%. Factors influencing 3-year all-cause mortality after multivariable adjustment were tumor stage (stage IV vs. stage 0-I: HR 8.72, 95% CI 6.77-11.24), comorbidity (Charlson comorbidity score ≥2 vs. 0: HR 1.63, 95% CI 1.39-1.90), age (>75 vs. <65 years: HR 1.48, 95% CI 1.24-1.78), and calendar period (2006-2010 vs. 2011-2015: HR 0.83, 95% CI 0.73-0.95). No independent prognostic influence was found for sex (women vs. men: HR 1.01, 95% CI 0.85-1.09), pre-operative chemotherapy (yes vs. no: HR 0.92, 95% CI 0.78-1.08), tumor sub-localization (non-cardia vs. cardia: HR 1.01, 95% CI 0.83-1.22), or education (≥13 vs. ≤9 years: HR 0.89, 95% CI 0.74-1.07). The results were similar for 3-year disease-specific mortality.

CONCLUSION

Survival after gastrectomy for gastric adenocarcinoma needs further improvement. Tumor stage, comorbidity, age, and calendar period were independently prognostic, while sex, pre-operative chemotherapy, tumor sub-localization, and education were not.

Hesperetin promotes DOT1L degradation and reduces histone H3K79 methylation to inhibit gastric cancer metastasis

BACKGROUND

There have been many researches on the effects of flavonoids on tumor treatment or adjuvant therapy, but there are few studies revealing their epigenetic effect on tumors. Hesperetin is a common citrus flavanone widely distributed among citrus fruits. The role of hesperetin in gastric cancer metastasis is unclear.

PURPOSE

To investigate the effect of hesperetin on gastric cancer metastasis and its underlying mechanism.

METHODS

We used cancer cell lines cultured in medium and nude mice implantation as in vitro and in vivo models to investigate the impact of hesperetin treatment on the migration and invasion of gastric cancer cells. The molecular biological experiments such as transwell assay, western blotting, qPCR, ChIP-qPCR, immunostaining and transfection were conducted to explore the molecular mechanisms.

RESULTS

We found that hesperetin obviously reduced the protein abundance of DOT1L and the methylation of histone H3K79 in a variety of cells. In gastric cancer cells, the treatment of hesperetin decreased cell migration and invasion and the expression of genes closely related to the metastatic capability. Mechanistically, hesperetin affected the stability of DOT1L protein by regulating the activity of CBP.

CONCLUSION

These findings highlight the epigenetic effect of hesperetin and provide a new perspective to understand the tumor suppressive effect of flavonoids.

Differentially expressed genes PCCA, ECHS1, and HADH are potential prognostic biomarkers for gastric cancer

Gastric cancer (GC) is one of the most common malignant tumors in the world. As far as we know, no biomarker has been widely accepted for early diagnosis and prognosis prediction of GC. The purpose of this study is to find potential biomarkers to predict the prognosis of GC. The differentially expressed gene (DEG) was analyzed from GSE93774. Enrichr was used to analyze the gene ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, the enrichment of transcription factors (TF), miRNA, and kinase. GO analysis showed DEGs was enriched in the process of amino acid metabolism. Pathway results showed DEGs was mainly enriched in cell cycle. Propionyl CoA carboxylase alpha (PCCA), Enoyl coenzyme A hydratase short chain 1 (ECHS1), and 3-hydroxyacyl-CoA dehydrogenase (HADH) have prognostic value in patients with GC. ECHS1 and HADH genes were significantly associated with disease-free survival. There was a significant correlation between PCCA and overall survival rate. The results of this study suggest that PCCA, ECHS1, and HADH may be new biomarkers for predicting the prognosis of GC.

Anticancer Properties of Lobetyolin, an Essential Component of Radix Codonopsis (Dangshen)

Lobetyolin (LBT) is a polyacetylene glycoside found in diverse medicinal plants but mainly isolated from the roots of Codonopsis pilosula, known as Radix Codonopsis or Dangshen. Twelve traditional Chinese medicinal preparations containing Radix Codonopsis were identified; they are generally used to tonify spleen and lung Qi and occasionally to treat cancer. Here we have reviewed the anticancer properties of Codonopsis extracts, LBT and structural analogs. Lobetyolin and lobetyolinin are the mono- and bis-glucosylated forms of the polyacetylenic compound lobetyol. Lobetyol and LBT have shown activities against several types of cancer (notably gastric cancer) and we examined the molecular basis of their activity. A down-regulation of glutamine metabolism by LBT has been evidenced, contributing to drug-induced apoptosis and tumor growth inhibition. LBT markedly reduces both mRNA and protein expression of the amino acid transporter Alanine-Serine-Cysteine Transporter 2 (ASCT2). Other potential targets are proposed here, based on the structural analogy with other anticancer compounds. LBT and related polyacetylene glycosides should be further considered as potential anticancer agents, but more work is needed to evaluate their efficacy, toxicity, and risk-benefit ratio.

Assessment of structural protein expression by FTIR and biochemical assays as biomarkers of metabolites response in gastric and colon cancer

Colon and gastric cancers are the widespread benign types of cancers which are synchronous and metachronous neoplasms. In terms of the progression and progress of the disease, metabolic processes and differentiation in protein structures have an important role in for treatment of the disease. In this study we proposed to investigate the metabolic process and the differentiation of protein secondary structure among colon and gastric cancer as well as healthy controls using biochemistry and Fourier Transform InfraRed spectroscopy (FTIR) methods. For this purpose, we measured blood serum of 133 patients, which were conducted upon oncology department (45 colon cancer, 45 gastric cancer and 43 control individuals). The obtained spectroscopic results and biochemical assays showed significant reduction in the amount of functional groups in cancer groups contrary with total protein measurements and structure of protein differences between colon and gastric cancers. Differentiations were visible in serum levels of CEA, CA-125, CA-15-3, CA-19-9 AFP (Alpha fetoprotein) of gastric and colon cancer patients as well as in amide III and secondly described amide I regions. Our findings suggest that amide I bonds in colon cancer cells can be helpful in diagnosis of colon cancer. Indeed, our results showed that metabolic processes were higher in gastric cancer group than in colon cancer. Hence, FTIR spectroscopy and curve-fitting analysis of amide I profile can be successfully applied as tools for identifying quantitative and qualitative changes of proteins in human cancerous blood serum. However, what is very important, in PCA analysis we see, that the scatter plot of PC1 (variability 80%) and PC2 (variability 15%) show that the data related to the control and two cancer groups are clustered together with different magnitudes and directions.

Characterization and clinical evaluation of microsatellite instability and loss of heterozygosity in tumor-related genes in gastric cancer

Microsatellite instability (MSI) detection is widely used in the diagnosis and prognosis evaluation of colorectal cancer. However, for gastric cancer (GC), there is no standard panel of microsatellites (MSs) used in clinical guidance. The present study aimed to identify useful predictors of the clinical features and for the prognosis of GC, based on an investigation of MSI and loss of heterozygosity (LOH) in tumor-related genes. First, from 20 tumor-related genes which were proven to be important to the development of GC, 91 MSs were identified, and PCR amplification, short tandem repeat scanning analysis and TA clone sequencing were used to analyze MSI and LOH in the first set of 90 GC samples. Subsequently, the same method was used to detect the MSI/LOH of the optimized loci in the second set of 136 GC samples. MSI/LOH in the mismatch repair genes was highly consistent with that in oncogenes and tumor suppressor genes, respectively. The length of the core sequence was a main factor for the MSI/LOH rate. The MSI of 12 single loci was significantly associated with lymph node metastasis. The MSI in TP53-1 and the LOH in MGMT-10 were significantly associated with early stages of tumor infiltration depth. The LOH in MGMT-10, PTN-2 and MCC-17 was significantly associated with TNM stage. The LOH in TP53-1 and ERBB2-12 was associated with adenocarcinoma. The MSI/LOH in 6 single loci of 5 tumor-related genes was associated with poor prognosis of GC. The present study demonstrated that the MSI/LOH of loci in tumor-associated genes was associated with 4 clinicopathological characteristics and outcomes of GC. These results may provide potential specific biomarkers for the clinical prediction and treatment of GC.

Detection of circulating tumor cells: Advances and critical concerns

Metastasis is the main cause of cancer-related death and the major challenge in cancer treatment. Cancer cells in circulation are termed circulating tumor cells (CTCs). Primary tumor metastasis is likely due to CTCs released into the bloodstream. These CTCs extravasate and form fatal metastases in different organs. Analyses of CTCs are clarifying the biological understanding of metastatic cancers. These data are also helpful to monitor disease progression and to inform the development of personalized cancer treatment-based liquid biopsy. However, CTCs are a rare cell population with 1-10 CTCs per ml and are difficult to isolate from blood. Numerous approaches to detect CTCs have been developed based on the physical and biological properties of the cells. The present review summarizes the progress made in detecting CTCs.

Situs inversus totalis patients with gastric cancer: Robotic surgery the standard of treatment?-A case report

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Situs inversus totalis is a very rare congenital anomaly.

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Variant anatomy will inevitably conflict with surgical habits.

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Minimally invasive surgery for situs inversus totalis patients has more advantages over traditional surgery.

Introduction and importance

Situs inversus totalis (SIT) is a very rare congenital condition. Situs inversus totalis (SIT) patients who present with gastric cancer have been reported in Japan, China, the United States, and other countries. China has a high incidence of gastric cancer, accounting for 40% of the global annual incidence. Surgical treatment options for situs inversus totalis (SIT) gastric cancer patients are of great concern due to the rare nature of the condition and the anatomical variations. This case aims to demonstrate the utility of robotic surgery in treating situs inversus totalis patients with gastric cancer.

Case presentation

We report a 69-year-old male situs inversus totalis (SIT) gastric cancer patient who successfully underwent a DaVinci robotic-assisted distal gastrectomy with Roux-en-Y reconstruction. The patient had no complications after the operation and was discharged postoperative day 15.

Clinical discussion

Gastric cancer is an aggressive disease that requires timely diagnosis and appropriate intervention. Unfortunately, many patients present late with gastric cancer and do not benefit from surgical or other appropriate interventions. Patients who are eligible for surgery however still need a clean marginal resection to maximize prognosis, which is not always possible due to complex anatomy or variations as seen in situs inversus totalis. DaVinci robotic surgery system is a new generation of minimally invasive operating systems after conventional laparoscopy, and its visual field clarity, operating flexibility, and instrument stability have obvious advantages over conventional laparoscopic surgery and traditional open surgery.

Conclusion

Robotic surgery for situs inversus totalis (SIT) patients is more advantageous than laparoscopic and traditional surgeries as it offers a broader view of the variant anatomy and allows optimum dexterity and clarity.

Changes of Body Mass Index and Body Shape in relation to risk of Gastric Cancer: A population-based case-control study

Background: The results of previous studies are heterogeneous about the effect of body fatness on risk of gastric cancer (GC). Herein we investigated the effect of changes of BMI and body shape on risk of GC.

Methods: A population-based case-control study enrolled 1989 controls and 937 GC cases. Logistic regression models were used to calculate odd ratios (ORs) and 95% confidence intervals (CIs) for BMI and body shape in association with GC risk, according to anatomical subsite, Laurén's classification, sex and Helicobacter pylori (Hp) infection.

Results: Subjects with higher BMI or body shape 10 years before interview had a lower risk of GC regardless of anatomical subsite, Laurén's classification, and sex (all P for trend <0.05). But the relative risk patterns were different by Hp status. When checking the effect of changes of body fatness, in Hp+ stratum, the ORs (95% CI) were 0.40 (0.17-0.93) for subjects who were underweight at age 20 but had increased BMI afterwards, and 0.48 (0.32-0.73) for those of body shape 1/2 at age 20 but increased body shape subsequently, compared to subjects with stable BMI or body shape. When subjects had a normal BMI or 3/4 body shape at age 20, weight loss nearly doubled the risk of GC, and weight gain would decrease the risk.

Conclusion: The association between body fatness and GC risk might differ by time point of measurement and Hp-infection status. Further, the influence of changes of body fatness might be different by baseline body fatness and Hp-infection status.

Gastric Cancer Presenting as Persistent Pneumonia: An Unusual Case Report

Worldwide, gastric cancer is the fifth most common cancer and the third leading cause of cancer deaths, which carries a poor prognosis as only 28.3% are expected to survive after five years. The incidence varies depending on the geographical locations and dietary patterns. Here, we present a case of a 59-year-old Hispanic male with a 10-month history of recurrent bilateral pneumonia and dysphagia. Diagnostic workup revealed metastatic gastric adenocarcinoma.

Molecular Subtypes and CD4+ Memory T Cell-Based Signature Associated With Clinical Outcomes in Gastric Cancer

Background

CD4⁺ memory T cells are an important component of the tumor microenvironment (TME) and affect tumor occurrence and progression. Nevertheless, there has been no systematic analysis of the effect of CD4⁺ memory T cells in gastric cancer (GC).

Methods

Three datasets obtained from microarray and the corresponding clinical data of GC patients were retrieved and downloaded from the Gene Expression Omnibus (GEO) database. We uploaded the normalize gene expression data with standard annotation to the CIBERSORT web portal for evaluating the proportion of immune cells in the GC samples. The WGCNA was performed to identify the modules the CD4⁺ memory T cell related module (CD4⁺ MTRM) which was most significantly associated with CD4⁺ memory T cell. Univariate Cox analysis was used to screen prognostic CD4⁺ memory T cell-related genes (CD4⁺ MTRGs) in CD4⁺ MTRM. LASSO analysis and multivariate Cox analysis were then performed to construct a prognostic gene signature whose effect was evaluated by Kaplan-Meier curves and receiver operating characteristic (ROC), Harrell’s concordance index (C-index), and decision curve analyses (DCA). A prognostic nomogram was finally established based on the CD4⁺ MTRGs.

Result

We observed that a high abundance of CD4⁺ memory T cells was associated with better survival in GC patients. CD4⁺ MTRM was used to stratify GC patients into three clusters by unsupervised clustering analysis and ten CD4⁺ MTRGs were identified. Overall survival, five immune checkpoint genes and 17 types of immunocytes were observed to be significantly different among the three clusters. A ten-CD4⁺ MTRG signature was constructed to predict GC patient prognosis. The ten-CD4⁺ MTRG signature could divide GC patients into high- and low-risk groups with distinct OS rates. Multivariate Cox analysis suggested that the ten-CD4⁺ MTRG signature was an independent risk factor in GC. A nomogram incorporating this signature and clinical variables was established, and the C-index was 0.73 (95% CI: 0.697–0.763). Calibration curves and DCA presented high credibility for the OS nomogram.

Conclusion

We identified three molecule subtypes, ten CD4⁺ MTRGs, and generated a prognostic nomogram that reliably predicts OS in GC. These findings have implications for precise prognosis prediction and individualized targeted therapy.

ARL4C might serve as a prognostic factor and a novel therapeutic target for gastric cancer: bioinformatics analyses and biological experiments

The ADP‐ribosylation factor‐like proteins (ARLs) have been proved to regulate the malignant phenotypes of several cancers. However, the exact role of ARLs in gastric cancer (GC) remains elusive. In this study, we systematically investigate the expression status, interactive relations, potential pathways, genetic variations and clinical values of ARLs in GC. We find that ARLs are significantly dysregulated in GC and involved in various cancer‐related pathways. Subsequently, machine learning models identify ARL4C as one of the two most significant clinical indicators among ARLs for GC. Furthermore, ARL4C silencing remarkably inhibits the growth and metastasis of GC cells both in vitro and in vivo. Moreover, enrichment analysis indicates that ARL4C is highly correlated with TGF‐β1 signalling. Correspondingly, TGF‐β1 treatment dramatically increases ARL4C expression and ARL4C knockdown inhibits the phosphorylation level of Smads, downstream factors of TGF‐β1. Meanwhile, the coexpression of ARL4C and TGF‐β1 worsens the prognosis of GC patients. Our work comprehensively demonstrates the crucial role of ARLs in the carcinogenesis of GC and the specific mechanisms underlying the GC‐promoting effects of TGF‐β1. More importantly, we uncover the great promise of ARL4C‐targeted therapy in improving the efficacy of TGF‐β1 inhibitors for GC patients.

Beyond the Guidelines: The Grey Zones of the Management of Gastric Cancer. Consensus Statements from the Gastric Cancer Italian Network (GAIN)

BACKGROUND

Management of gastric and gastroesophageal junction (GEJ) adenocarcinoma remains challenging, because of the heterogeneity in tumor biology within the upper gastrointestinal tract. Daily clinical practice is full of grey areas regarding the complexity of diagnostic, staging, and therapeutic procedures. The aim of this paper is to provide a guide for clinicians facing challenging situations in routine practice, taking a multidisciplinary consensus approach based on available literature.

METHODS

The GAIN (GAstric cancer Italian Network) group was established with the aims of reviewing literature evidence, discussing key issues in prevention, diagnosis, and management of gastric and GEJ adenocarcinoma, and offering a summary of statements. A Delphi consensus method was used to obtain opinions from the expert panel of specialists.

RESULTS

Forty-nine clinical questions were identified in six areas of interest: role of multidisciplinary team; risk factors; diagnosis; management of early gastric cancer and multimodal approach to localized gastric cancer; treatment of elderly patients with locally advanced resectable disease; and treatment of locally advanced and metastatic cancer.

CONCLUSIONS

The statements presented may guide clinicians in practical management of this disease.

Perioperative Safety and Effectiveness of Neoadjuvant Therapy with Fluorouracil, Leucovorin, Oxaliplatin, and Docetaxel Plus Apatinib in Locally Advanced Gastric Cancer

Purpose

The trend in neoadjuvant therapy for locally advanced gastric cancer (LAGC) is to use more drugs or therapies in combination. This study aimed to assess the safety and effectiveness of neoadjuvant chemotherapy with fluorouracil, leucovorin, oxaliplatin, and docetaxel (FLOT) plus apatinib in the treatment of LAGC.

Patients and Methods

We collected clinical data from patients with LAGC who received neoadjuvant FLOT and apatinib therapy and underwent surgery from January 2017 to December 2020. Patients were divided into either the FLOT group (in which patients received FLOT neoadjuvant therapy and surgery) or the FLOTA group (in which patients received FLOT plus apatinib neoadjuvant therapy and surgery).

Results

The FLOT and FLOTA groups contained 44 and 31 patients, respectively. There were significant differences between the FLOT and FLOTA groups in the objective response rate (50.00% vs. 80.65%, respectively, p = 0.008) and average change from baseline in the target lesion size (−26.16 ± 34.61 vs. −54.32 ± 36.11, respectively, p < 0.001). There were also significant differences in the pretreatment clinical tumor-node-metastasis (cTNM) and post treatment cTNM stages for the FLOT group (p = 0.001) and for the FLOTA group (p < 0.001). There were no significant differences between the FLOT and FLOTA groups in post neoadjuvant therapy cTNM stages (p = 0.525), R0 rate (p = 0.397), tumor regression grade (p = 0.397), or post treatment pathological TNM stage (p = 0.180). Some neoadjuvant therapy-related adverse events occurred significantly more frequently in the FLOTA group, including diarrhea (all grades), pain (all grades), oral mucositis (all grades), and hand-foot syndrome (all grades).

Conclusion

The FLOTA regimen can achieve better perioperative efficacy and acceptable toxicity compared with that of the FLOT regimen in neoadjuvant treatment of LAGC. The FLOTA regimen for neoadjuvant therapy for LAGC merits further study.

Progress of Gastric Cancer Surgery in the era of Precision Medicine

With the development of genomics, the update of modern imaging technology and the advent of artificial intelligence and big data, the surgical treatment of gastric cancer has gradually stepped into precision medicine. Precision surgery treatment of gastric cancer is based on accurate molecular typing and staging using modern molecular diagnostic technology and imaging, and the formulation of precise and individualized surgical treatment plans, with the concept of minimally invasive and accelerated rehabilitation surgery running through it. For intermediate-stage gastric cancer, we have adopted a comprehensive treatment approach including traditional radiotherapy and chemotherapy, targeted therapy and immunotherapy. Utilize artificial intelligence and big data technology to improve the standardization and interconnectivity of specialty data and realize the transformation of evidence-based medicine. Promoting the standardization, standardization and individualization of gastric cancer surgical treatment, providing patients with precise diagnosis and treatment, and further improving patients' prognosis are the opportunities and challenges in the development of gastric cancer surgery.

New immunoprobe: Dual-labeling ZIF-8 embellished with multifunctional bovine serum albumin lamella for electrochemical immunoassay of tumor marker

A new immunoprobe, which can initiate the sedimentation of Ag nanoparticles (NPs) on an electrode surface, was developed for the electrochemical detection of carbohydrate antigen 72-4 (CA 72-4). To design the immunoprobe, zeolitic imidazolate frameworks (ZIFs) were employed as the carrier to enrich thionine molecules, then bovine serum albumin (BSA) was modified on the electrode surface. Advantageously, BSA, served as an anchor to further attach the labeling antibodies (Ab₂) and alkaline phosphatase (ALP) to also be modified on the surface through covalent bonding. To construct the immunosensor, multiwalled carbon nanotube-graphene oxide composites were employed to provide active sites, and the electrodeposited Au NPs were used to immobilize coating antibodies. In the presence of CA 72-4, a sandwich immunosensor was established, and a cascade reaction was initiated to deposit Ag NPs under the catalysis, which can further improve the conductivity of electrode interface. Under the optimal conditions, the immunosensor displayed excellent performance with a wide linear range from 1 μU mL^-1 to 10 U mL^-1 and an ultralow detection limit of 0.438 μU mL^-1 (S/N = 3).

IL-17B/IL-17RB signaling cascade contributes to self-renewal and tumorigenesis of cancer stem cells by regulating Beclin-1 ubiquitination

Cancer stem cells (CSCs) are characterized by robust self-renewal and tumorigenesis and are responsible for metastasis, drug resistance, and angiogenesis. However, the molecular mechanisms for the regulation of CSC homeostasis are incompletely understood. This study demonstrated that the interleukin-17 (IL-17)B/IL-17RB signaling cascade promotes the self-renewal and tumorigenesis of CSCs by inducing Beclin-1 ubiquitination. We found that IL-17RB expression was significantly upregulated in spheroid cells and Lgr5-positive cells from the same tumor tissues of patients with gastric cancer (GC), which was closely correlated with the degree of cancer cell differentiation. Recombinant IL-17B (rIL-17B) promoted the sphere-formation ability of CSCs in vitro and enhanced tumor growth and metastasis in vivo. Interestingly, IL-17B induced autophagosome formation and cleavage-mediated transformation of LC3 in CSCs and 293T cells. Furthermore, inhibition of autophagy activation by ATG7 knockdown reversed rIL-17B-induced self-renewal of GC cells. In addition, we showed that IL-17B also promoted K63-mediated ubiquitination of Beclin-1 by mediating the binding of tumor necrosis factor receptor-associated factor 6 to Beclin-1. Silencing IL-17RB expression abrogated the effects of IL-17B on Beclin-1 ubiquitination and autophagy activation in GC cells. Finally, we showed that IL-17B level in the serum of GC patients was positively correlated with IL-17RB expression in GC tissues, and IL-17B could induce IL-17RB expression in GC cells. Overall, the results elucidate the novel functions of IL-17B for CSCs and suggest that the intervention of the IL-17B/IL-17RB signaling pathway may provide new therapeutic targets for the treatment of cancer.

Small Proline-Rich Protein 2B Facilitates Gastric Adenocarcinoma Proliferation via MDM2-p53/p21 Signaling Pathway

Background

The small proline-rich protein 2B (SPRR2B) was firstly reported as a member of the cross-linked envelope protein in keratinocytes. The effect of SPRR2B in gastric adenocarcinoma (GC) remains unclear. This study initially explored the clinical significance of SPRR2B in GC patients as well as its role in tumor progression.

Methods

Immunohistochemistry was performed to characterize the expression of SPRR2B in GC tissues and adjacent tissues. The relationship between SPRR2B expression and clinicopathological features of GC patients was analyzed by Chi-square test. Kaplan-Meier method and Cox regression analyses were utilized to identify the prognostic factors of GC. Overexpression and knockdown assays were conducted to investigate possible signaling pathways downstream of SPRR2B. Flow cytometry assays were performed to evaluate cell cycle and apoptosis. Xenograft experiments were performed to validate tumor-related role of SPRR2B in vivo.

Results

Both mRNA and protein levels of SPRR2B in cancerous tissue were significantly higher than those in non-cancerous tissues. Meanwhile, SPRR2B expression was significantly associated with tumor size and tumor stage. Survival analysis revealed SPRR2B as one of the independent prognosis factors for overall survival of GC patients. Cellular and xenografts data implicated that silencing SPRR2B blocked the cell cycle of GC cells perhaps through MDM2-p53/p21-CDK1 pathway, while overexpressing SPRR2B exhibited opposite effects.

Conclusion

Our data suggest that SPRR2B may serve as a novel prognostic marker in GC, which functions at least partially by MDM2-p53/p21-CDK1 signaling pathway.

Targeting miR-148b-5p Inhibits Immunity Microenvironment and Gastric Cancer Progression

Background

MicroRNAs (miRNAs) have been discovered to dictate the development of various tumors. However, studies on the roles of miRNAs in the progression of gastric cancer (GC) are still lacking.

Methods

Herein, by analyzing GC cell lines and patients samples, we observed that miR-148b-5p was significantly downregulated in GC. We also confirmed that miR-148b-5p overexpression significantly inhibited GC cell proliferation and invasion in vitro and in vivo.

Results

Overexpression of miR-148b-5p not only reprogrammed the metabolic properties of GC but also regulated the immune microenvironment by shifting lymphocyte and myeloid populations. Mechanistically, ATPIF1, an important glycolysis-associated gene, was identified as a direct target of miR-148b-5p and mediated the effect of miR-148b-5p. Notably, the low level of miR-148b-5p was significantly related with poor prognosis of GC patients (P < 0.001). Importantly, the levels of miR-148b-5p significantly changed the sensitivity of GC cells to several anti-cancer drugs (Doxorubicin, P < 0.05, Paclitaxel, P < 0.01, Docetaxel, P < 0.05).

Conclusions

Targeting miR-148b-5p inhibits immunity microenvironment and gastric cancer progression.

Role of the long non-coding RNA LINC00052 in tumors

Long intergenic non-protein coding RNA 52 (LINC00052) is a non-coding RNA with >200 nucleotides in length, which exerts important effects on several physiological and pathological processes of the human body. Recent studies have demonstrated that LINC00052 plays key roles in the tumorigenesis, progression and metastasis of multiple types of human cancer, including hepatocellular carcinoma, breast cancer, colorectal cancer, cervical carcinoma and gastric cancer. However, the associations between LINC00052 and these tumors remain unclear. The present review summarizes the biological functions of LINC00052 during the pathogenic process of certain tumors, and discusses its potential therapeutic targets.

Molecular modelling of the gastric barrier response, from infection to carcinogenesis

The lining of the stomach is a tight monolayer of epithelial cells performing functions in digestion and a protective barrier against gastric acid, toxic metabolites and infectious agents, including Helicobacter pylori. The response of the epithelial barrier to infections underlies gastric pathologies, including gastric cancer. H. pylori has the unique capacity to colonise the gastric mucosa while evading the immune system. The colonised mucosa initiates an inflammatory response to fight the infection and a strong regenerative program to avoid barrier failure and ulceration. This response changes the morphology and cell composition of the gastric epithelium and in parallel it might contribute to the accumulation of somatic mutations leading to cellular transformation. Genetically modified mice, cell lines and human-derived organoids are the main biological models to study the gastric epithelial barrier. With these models it is possible to dissect the stepwise process of tissue adaptation to infection that places the epithelium at risk of malignant transformation.

Effectiveness of acupuncture for the recovery of gastrointestinal function of patients with gastric cancer in the postoperative period: A protocol for systematic review and meta-analysis

BACKGROUND

Gastric cancer (GC) is the most common malignant tumors in the world and surgical resection remains the primary treatment for it. Postoperative patients often suffer from gastrointestinal dysfunction as the most common side effects of surgery for GC patients. Acupuncture has a regulatory effect on gastrointestinal function. We conducted this study to assess the effectiveness of acupuncture on the restoration of gastrointestinal function of postoperative patients with GC.

METHODS

Seven electronic databases will be searched from inception to November 2020 to identify any relevant study: Medline, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), China National Knowledge Infrastructure (CNKI), Wanfang Database, Chinese Biomedical Literature Database (CBM), and Chinese Scientific Journal Database (VIP database). No restriction on time and language. The primary outcome measure will be the Time to First Flatus and secondary outcome measures include the time of first defecation and the quality of life (QOL) and the number of patients with abdominal distention. We will use EndNote V.9.1 to screen the eligible literature and the I2 statistic to assess heterogeneity in the included studies. The meta-analysis will be conducted using the Review Manager (RevMan) software (V.5.3).

RESULTS

Our study aims to systematically assess whether the pooled effects of currently available trials prove effects of acupuncture in improving gastrointestinal function of patients with GC in the postoperative period.

CONCLUSION

This study will conduct an evaluation about the efficacy of acupuncture for the recovery of gastrointestinal function of patients with GC in the postoperative period, making up for the lack of relevant clinical evidence.

INPLASY REGISTRATION NUMBER

INPLASY2020110066.

Long non-coding RNA BX357664 inhibits gastric cancer progression by sponging miR-183a-3p to regulate the PTEN expression and PI3K/AKT pathway

Lately, long non-coding RNA (lncRNA) is recognized as a key regulator of gastric cancer (GC) which has aroused great interest in the fields of medicine, toxicology, and functional food. Studies related to LncRNA expression microarray data indicate that BX357664 is down-regulated in GC specimens. However, the expression pattern and molecular mechanism of BX357664 in GC have not been studied so far. The purpose of this study was to investigate the expression of lncRNA BX357664 in GC and its function in GC cell lines. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the level of BX357664 in 50 pairs of cancer tissues and adjacent non-cancer tissues collected from GC patients. It was found that BX357664 level was lowered in cancer specimens than adjacent non-cancer tissues and correlated with tumor size and TNM stage. Also, we used cell counting kit 8 (CCK8), cell clone formation assay and transwell assay, which affirmed that up-regulation of BX357664 inhibited the proliferation, migration, and invasion of GC cells, but promoted apoptosis. In the dual-luciferase report analysis, BX357664 acted as a miR-183-3p ceRNA to target and regulate the expression of PTEN and affect the PI3K/AKT pathway. These results indicate that BX357664 can inhibit the proliferation and metastasis of GC through the miR-183-3p/PTEN/PI3K/AKT pathway, which may serve as potential targets for the treatment of GC in the future.

FENDRR: A pivotal, cancer-related, long non-coding RNA

Long non-coding RNAs (lncRNAs) have more than 200 nucleotides and do not encode proteins. Based on numerous studies, lncRNAs have emerged as new and crucial regulators of biological function and have been implicated in the pathogenesis of a variety of diseases, especially cancers. Specific lncRNAs have been identified as novel molecular biomarkers for cancer diagnosis, prognosis, and treatment efficacy. Fetal-lethal non-coding developmental regulatory RNA (FENDRR, also known as FOXF1-AS1) is a novel lncRNA that is located at chr3q13.31 and has four exons and 3099 nucleotides, and its genomic site is located at chr3q13.31. FENDRR is abnormally expressed in a variety of cancers and is significantly associated with different clinical characteristics. In addition, FENDRR has shown potential as a biomarker for cancer diagnosis, prognosis, and treatment. In this review, we summarize the current understanding of FENDRR and its mechanistic role in cancer progression. We also discuss recent insights into the clinical significance of FENDRR for cancer diagnosis, prognosis, and treatment.

LINC00242/miR-1-3p/G6PD axis regulates Warburg effect and affects gastric cancer proliferation and apoptosis

BACKGROUND

Reprogrammed glucose metabolism of enhanced Warburg effect (or aerobic glycolysis) is considered as a hallmark of cancer. Long non-coding RNAs (lncRNAs) have been certified to play a crucial role in tumor progression. The current study aims to inquire into the potential regulatory mechanism of long intergenic non-protein coding RNA 242 (LINC00242) on aerobic glycolysis in gastric cancer.

METHOD

LINC00242, miR-1-3p and G6PD expression levels in gastric cancer tissues and cells were determined by qRT-PCR. Cell apoptosis or viability were examined by Flow cytometry or MTT assay. Western blot was utilized to investigate G6PD protein expression levels. Immunohistochemical (IHC) and hematoxylin and eosin (H&E) staining were used for histopathological detection. The targeted relationship between LINC00242 or G6PD and miR-1-3p was verified by luciferase reporter gene assay. Nude mouse xenograft was utilized to detect tumor formation in vivo.

RESULT

LINC00242 and G6PD was high-expressed in gastric cancer tissues and cells, and LINC00242 is positively correlated with G6PD. Silencing of LINC00242 or G6PD within gastric cancer cells prominently inhibited cell proliferation and aerobic glycolysis in vitro and relieved the tumorigenesis of gastric cancer in vivo. miR-1-3p was predicted to directly target both LINC00242 and G6PD. Overexpression of miR-1-3p suppressed gastric cancer cells proliferation and aerobic glycolysis. LINC00242 competitively combined miR-1-3p, therefore relieving miR-1-3p-mediated suppression on G6PD.

CONCLUSION

LINC00242 plays a stimulative role in gastric cancer aerobic glycolysis via regulation of miR-1-3p/ G6PD axis, therefore affecting gastric cancer cell proliferation.

Low Pretreatment Albumin-to-Globulin Ratio Predicts Poor Prognosis in Gastric Cancer: Insight From a Meta-Analysis

BACKGROUND

In recent five years, reports regarding albumin-to-globulin ratio (AGR) and the survival of gastric cancer (GC) have emerged rapidly, yet their association remains controversial. This meta-analysis was aimed to provide an insight into the prognostic significance of pretreatment AGR in GC.

METHODS

PubMed, Embase, Cochrane library, Web of Science, WanFang, China National Knowledge Infrastructure (CNKI) and VIP databases were searched for relevant studies, from inception to September 30, 2020. Individual hazard ratios (HRs) with their 95% confidence intervals (CIs) were combined by Stata 12.0 software to evaluate the association between pretreatment AGR and overall survival (OS) and disease-free survival/progression-free survival (DFS/PFS).

RESULTS

A total of 8,305 patients with GC from 12 studies were included for further analysis. Pooled analyses indicated that low AGR was closely associated with worse OS (HR = 1.531, 95% CI: 1.300-1.803, P < 0.001) and worse DFS/PFS (HR = 2.008, 95% CI: 1.162-3.470, P = 0.012) in GC patients. Moreover, subgroup analyses demonstrated that the association between low AGR and worse OS remained constant despite variations in country, tumor stage, cut-off value, cut-off selection and treatment method.

CONCLUSION

AGR could act as an efficient prognostic indicator for GC, and that low pretreatment AGR predicts poor prognosis in GC.

Endoscopic Ultrasound vs. Computed Tomography for Gastric Cancer Staging: A Network Meta-Analysis

Gastric cancer preoperative staging is of outmost importance to assure proper management of the disease. Providing a relevant clinical stage relies on different imaging methods such as computed tomography (CT) or endoscopic ultrasound (EUS). We aimed to perform a network meta-analysis for gastric cancer clinical stage diagnostic tests, thus comparing the diagnostic accuracy of EUS vs. multidetector CT (MDCT) and EUS vs. EUS + MDCT. We plotted study estimates of pooled sensitivity and specificity on forest plots and summary receiver operating characteristic space to explore between-study variation in the performance of EUS, MDCT and EUS + MDCT for T1–T4, N0–N3, M0–M1 when data were available. Exploratory analyses were undertaken in RevMan 5. We included twelve studies with 2047 patients. Our results suggest that EUS was superior to MDCT in preoperative T1 and N staging. MDCT is more specific for the M stage but no significant difference in sensitivity was obtained. When comparing EUS vs. EUS + MDCT for T1 both sensitivity and specificity were not relevant. No significant differences were observed in T2–T4 stages. Even though EUS helped differentiate between the presence of invaded nodules, N stages should be carefully assessed by both methods since there is not sufficient data.

Complementary and alternative therapies for precancerous lesions of gastric cancer: A protocol for a Bayesian network meta analysis

BACKGROUND

Gastric cancer is one of the most common malignant tumors, which seriously affect peoples quality of life and threaten people's health. Precancerous lesions of gastric cancer (PLGC) are a critical stage in the occurrence and development of gastric cancer. Early effective intervention is an important means to prevent and control gastric cancer. In this study, we will evaluate the efficacy and safety of complementary and alternative therapies in the treatment of PLGC by Bayesian network meta-analysis (NMA).

METHODS

We will search PubMed, Cochrane Library, CNKI and other databases to gather randomized controlled trials (RCTs) on the treatment of PLGC with complementary and alternative therapies. Two reviewers will screen the literature and extract the data according to the inclusion and exclusion criteria, and then assess the quality and bias risk according to Cochrane's Risk of Bias Assessment Tool. Bayesian network meta-analysis will be conducted by Stata16.0 and WinBUGS1.4.3.

RESULTS

This study will compare and rank the efficacy and safety of different complementary and alternative therapies for PLGC.

CONCLUSION

This study can provide reliable evidence for the efficacy and safety of complementary and alternative therapies in treatment of PLGC. We expect to provide scientific and rigorous evidence support for clinicians and patients, and then assist them to choose the optimum treatment.

PROTOCOL REGISTRATION NUMBER

INPLASY2020120077.

Screening for gastric cancer in China: Advances, challenges and visions

Gastric cancer (GC) is one of the major cancers in China and all over the world. Most GCs are diagnosed at an advanced stage with unfavorable prognosis. Along with some other countries, China has developed the government-funded national screening programs for GC and other major cancers. GC screening has been shown to effectively decrease the incidence of and mortality from GC in countries adopting nationwide screening programs (Japan and Korea) and in studies based on selected Chinese populations. The screening of GC relies mostly on gastroendoscopy, the accuracy, reliability and safety of which have been indicated by previous studies. However, considering its invasive screening approach, requirements on skilled endoscopists and pathologists, and a high cost, developing noninvasive methods to amend endoscopic screening would be highly needed. Numerous studies have examined biomarkers for GC screening and the combination of biomarkers involving pepsinogen, gastrin, and Helicobacter pylori antibodies has been proposed for risk stratification, seeking to narrow down the high-risk populations for further endoscopy. Despite all the achievements of endoscopic screening, evidence on appropriate screening age, intervals for repeated screening, novel biomarkers promoting precision prevention, and health economics need to be accumulated to inform policymakers on endoscopic screening in China. With the guide of Health China 2030 Planning Outline, we have golden opportunities to promote prevention and control of GC. In this review, we summarize the characteristics of screening programs in China and other East Asian countries and introduce the past and current approaches and strategies for GC screening, aiming for featuring the latest advances and key challenges, and illustrating future visions of GC screening.

Bibliometric Evaluation of Publications (2000-2020) on the Prognosis of Gastric Cancer

Background: Gastric cancer remains a global malignancy. The role of bibliometric analysis is increasingly valued. It is feasible and necessary to perform a bibliometric analysis to regurgitate studies in the prognosis of gastric cancer. Materials and methods: Web of Science was selected for the dataset resource. Articles published between 2000 and 2020 within the database of Web of Science Core Collection were included with predefined search terms. CiteSpace version 5.7.R1 and R software program version 4.0.3 were used for bibliometric analysis with parameters extrapolated from included studies. Results: A total of 1721 articles were included from 2000 to 2020 with remarkably increasing trends. China (n=1183), Japan (n=218), and South Korea (n=119) showed the most publications. SUN YAT SEN University, FUDAN University, and NANJING MED University were the top institutions with most publications. Keywords with strongest citation bursts between 2000 and 2020 were characterized. Particularly, “statistics”, “resistance”, “mortality”, “lncrna”, “diagnosis”, “outcome”, “migration”, “promote,” and “regulatory t cell” were the latest rising keywords since 2017, indicating possible study trends ahead. Several articles showed strongest citation bursts, including Jemal A. CA-CANCER J CLIN, Van Cutsem E. LANCET, and Japanese Gastric Cancer Association GASTRIC CANCER. Conclusion: This bibliometric analysis provides a thought-provoking, insightful result concerning the trajectory of research development in prognosis of gastric cancer with a future perspective.

Synergism of rMV-Hu191 with cisplatin to treat gastric cancer by acid sphingomyelinase-mediated apoptosis requiring integrity of lipid raft microdomains

BACKGROUND

DDP-based chemotherapy is one of the first-line treatment in GC. However, the therapeutic efficacy of DDP is limited due to side effects. Therefore, it is of great significance to develop novel adjuvants to synergize with DDP. We had demonstrated previously that rMV-Hu191 had antitumor activity in GC. Here we examined the synergism of rMV-Hu191 with DDP in vitro and in vivo.

METHODS

Cellular proliferation, the synergistic effect and cell apoptosis were evaluated by CCK-8 assay, ZIP analysis and flow cytometry, respectively. The protein levels and location of ASMase were monitored by western blot and immunofluorescence assay. shRNA and imipramine were used to regulate the expression and activity of ASMase. MβCD was administrated to disrupt lipid rafts. Mice bearing GC xenografts were used to confirm the synergism in vivo.

RESULTS

From our data, combinational therapy demonstrated synergistic cytotoxicity both in resistant GC cell lines from a Chinese patient and drug-nonresistant GC cell lines, and increased cell apoptosis, instead of viral replication. Integrity of lipid rafts and ASMase were required for rMV-Hu191- and combination-induced apoptosis. The ASMase was delivered to the lipid raft microdomains at the initial stage of rMV-Hu191 treatment. In vivo GC mice xenografts confirmed the synergism of combinational treatment, together with increased apoptosis and trivial side-effects.

CONCLUSIONS

This is the first study to demonstrate that rMV-Hu191 combined with DDP could be used as a potential therapeutic strategy in GC treatment and the ASMase and the integrity of lipid rafts are required for the synergistic effects.

A novel genomic classification system of gastric cancer via integrating multidimensional genomic characteristics

BACKGROUND

Gastric cancer (GC) is one of the leading causes of cancer deaths with high heterogeneity. There is currently a paucity of clinically applicable molecular classification system to guide precise medicine.

METHODS

A total of 70 Chinese patients with GC were included in this study and whole-exome sequencing was performed. Unsupervised clustering was undertaken to identify genomic subgroups, based on mutational signature, copy number variation, neoantigen, clonality, and essential genomic alterations. Subgroups were characterized by clinicopathological factors, molecular features, and prognosis.

RESULTS

We identified 32 significantly mutated genes (SMGs), including TP53, ARID1A, PIK3CA, CDH1, and RHOA. Of these, PREX2, PIEZO1, and FSIP2 have not been previously reported in GC. Using a novel genome-based classification method that integrated multidimensional genomic features, we categorized GC into four subtypes with distinct clinical phenotypes and prognosis. Subtype 1, which was predominantly Lauren intestinal type, harbored recurrent TP53 mutation and ERBB2 amplification, high tumor mutation burden (TMB)/tumor neoantigen burden (TNB), and intratumoral heterogeneity, with a liver metastasis tendency. Subtype 2 tended to occur at an elder age, accompanying with frequent TP53 and SYNE1 mutations, high TMB/TNB, and was associated with poor prognosis. Subtype 3 and subtype 4 included patients with mainly diffuse/mixed type tumors, high frequency of peritoneal metastasis, and genomical stability, whereas subtype 4 was associated with a favorable prognosis.

CONCLUSIONS

By integrating multidimensional genomic characteristics, we proposed a novel genomic classification system of GC associated with clinical phenotypes and provided a new insight to facilitate genome-guided risk stratification and disease management.

<p>Case–Control Study on <em>TNFRSF6B</em> Gene Polymorphism and Susceptibility to Gastric Cancer in a Chinese Han Population</p>

Purpose

To explore the relationship between rs2297440 and rs2297441 polymorphisms of TNFRSF6B gene and susceptibility to gastric cancer.

Methods

A hospital-based case-control study was conducted. A total of 577 gastric cancer cases and 678 normal controls were recruited. Their genotypes were determined using the SnapShot method.

Results

The smoking rate in the case group (34.49%) was higher than that in the control group (27.29%). For TNFRSF6B rs2297440, among people <62 years old, the risk of gastric cancer in TC people was 1.84 times that in TT people. Among the non-drinking people, the risk of gastric cancer in the CC type was 0.66 times that in the TT+TC type. Among the drinking population, the risk of gastric cancer in the TC type was 1.67 times that in the TT type, and the risk in the TC+CC type was 1.70 times that in the TT type. As for TNFRSF6B rs2297441, in males and non-drinkers, the risk of gastric cancer in the AG type was less than that in the GG type. No matter how old the patient is, the risk of gastric cancer in the AA type was less than that in the AG+GG type.

Conclusion

A correlation exists between smoking and gastric cancer. For TNFRSF6B rs2297440, the TC genotype may be a risk factor for gastric cancer in people <62 years old. In the non-drinking population, the homozygous mutant of CC may be a protective factor for gastric cancer. In the drinking population, TC type may be a risk factor, whereas the TC+CC type dominated by C may be a protective factor. For TNFRSF6B rs2297441, the AG genotype may be a risk factor for gastric cancer in males and non-drinkers. The AA homozygous mutant may be a protective factor for gastric cancer.

NAD(P)-dependent steroid dehydrogenase-like protein and neutral cholesterol ester hydrolase 1 serve as novel markers for early detection of gastric cancer identified using quantitative proteomics

BACKGROUND

Gastric cancer (GC) is the third most common cause of cancer deaths worldwide. In the present study, we aimed to identify novel GC biomarkers by integrating isobaric tags of relative and absolute quantitation (iTRAQ) for aberrantly expressed proteins in GC patients.

METHODS

Using stable isotope tags, we labeled an initial discovery group comprising four paired gastric cancer and adjacent gastric tissue samples, and subjected them to LC-ESI-MS/MS. We used a validation set comprising 129 paired gastric cancer and adjacent gastric tissues from patients and benign healthy controls to validate the candidate targets.

RESULTS

We identified two proteins, NAD(P)-dependent steroid dehydrogenase-like (NSDHL) and neutral cholesterol ester hydrolase 1 (NCEH1), that were significantly overexpressed in GC tissues. The sensitivity and specificity of NSDHL were 80.6% and 74.4%, respectively, in GC compared with a sensitivity of 25.6% in adjacent tissues and 24% in benign healthy controls. The area under the ROC curve (AUC) for NSDHL was 0.810 for GC detection. Overexpression of NSDHL in GC was significantly correlated with local tumor invasion. The sensitivity and specificity of NCEH1 were 77.5% and 73.6%, respectively, in GC compared with a sensitivity of 26.4% in adjacent tissues and 20% in benign controls. The AUC for NSDHL was 0.792. Overexpression of NCEH1 was significantly associated with tumor histological classification and local invasion. Moreover, a combined analysis of NSDHL and NCEH1 achieved a sensitivity and specificity of 85.7% and 83%, respectively, and the AUC was 0.872. The combined analysis of NSDHL and NCEH1 was significantly correlated with histological grade and TNM Ⅱ-Ⅳ staging.

CONCLUSIONS

iTRAQ-labeled quantitative proteomics represents a powerful method to identify novel cancer biomarkers. The present study identified NSDHL and NCEH1 as useful biomarkers for screening, diagnosis, and prognosis of patients with gastric cancer.