Aktuelle Biomarker beim Magenkarzinom

Identification of Kynurenic Acid-Induced Apoptotic Biomarkers in Gastric Cancer-Derived AGS Cells through Next-Generation Transcriptome Sequencing Analysis

Understanding the triggers and therapeutic targets for gastric cancer, one of the most common cancers worldwide, can provide helpful information for the development of therapeutics. RNA sequencing technology can be utilized to identify complex disease targets and therapeutic applications. In the present study, we aimed to establish the pharmacological target of Kynurenic acid (KYNA) for gastric cancer AGS cells and to identify the biological network. RNA sequencing identified differentially expressed genes (DEGs) between KYNA-treated and untreated cells. A total of 278 genes were differentially expressed, of which 120 genes were up-regulated, and 158 genes were down-regulated. Gene ontology results confirmed that KYNA had effects such as a reduction in genes related to DNA replication and nucleosome organization on AGS cells. Protein-protein interaction was confirmed through STRING analysis, and it was confirmed that cancer cell growth and proliferation were inhibited through KEGG, Reactome, and Wiki pathway analysis, and various signaling pathways related to cancer cell death were induced. It was confirmed that KYNA treatment reduced the gene expression of cancer-causing AP-1 factors (Fos, Jun, ATF, and JDP) in AGS cell lines derived from gastric cancer. Overall, using next-generation transcriptome sequencing data and bioinformatics tools, we confirmed that KYNA had an apoptosis effect by inducing changes in various genes, including factor AP-1, in gastric cancer AGS cells. This study can identify pharmacological targets for gastric cancer treatment and provide a valuable resource for drug development.

Blood index panel for gastric cancer detection

BACKGROUND

Gastric cancer is a common malignant tumor. Early detection and diagnosis are crucial for the prevention and treatment of gastric cancer.

AIM

To develop a blood index panel that may improve the diagnostic value for discriminating gastric cancer and gastric polyps.

METHODS

Thirteen tumor-related detection indices, 38 clinical biochemical indices and 10 cytokine indices were examined in 139 gastric cancer patients and 40 gastric polyp patients to build the model. An additional 68 gastric cancer patients and 22 gastric polyp patients were enrolled for validation. After area under the curve evaluation and univariate and multivariate analyses.

RESULTS

Five tumor-related detection indices, 12 clinical biochemical indices and 1 cytokine index showed significant differences between the gastric cancer and gastric polyp groups. Carbohydrate antigen (CA) 724, phosphorus (P) and ischemia-modified albumin (IMA) were included in the blood index panel, and the area under the curve (AUC) of the index panel was 0.829 (0.754, 0.905). After validation, the AUC was 0.811 (0.700, 0.923). Compared to the conventional index CA724, the blood index panel showed significantly increased diagnostic value.

CONCLUSION

We developed an index model that included CA724, P and IMA to discriminate the gastric cancer and gastric polyp groups, which may be a potential diagnostic method for clinical practice.

miR-187/PDLIM1 Gets Involved in Gastric Cancer Progression and Cisplatin Sensitivity of Cisplatin by Mediating the Hippo-YAP Signaling Pathway

Gastric cancer (GC) is one of the most prevalent malignancies in the digestive system across the world. The function and mechanism of PDLIM1, a cancer-suppressing gene, in gastric cancer progression remain unclear. This study is aimed at investigating the expression features and function of PDLIM1 in GC. RT-qPCR and western blot were used to compare the profiles of PDLIM1 and miR-187 between GC and normal tissues. The cell models of PDLIM1 overexpression and low expression were established in gastric cancer cell lines MKN45 and AGS. CCK8 and BrdU assays measured cell proliferation. Flow cytometry monitored cell apoptosis. Transwell analyzed cell invasion and migration. The influence of miR-187 overexpression on gastric cancer development was assessed. We predicted the targeted correlation between miR-187 and PDLIM1 through bioinformatics, which was corroborated via dual luciferase activity assay and RIP. Meanwhile, the cell model of PDLIM1 overexpression was built in AGS cells transfected with miR-187 mimics. A rescue experiment was conducted to assess the impact of PDLIM1 overexpression on the procancer function of miR-187. As a result, in contrast with normal paracancer tissues, PDLIM1 was substantially downregulated in GC tissues. Moreover, PDLIM1 overexpression considerably dampened proliferation, invasion, and migration in GC cells, boosted the cell apoptosis, and bolstered their sensitivity to cisplatin. PDLIM1 knockdown or miR-187 overexpression dramatically fostered GC cell proliferation, invasion, and migration and repressed cell apoptosis. Mechanism studies demonstrated that PDLIM1 vigorously restrained the profiles of the Hippo-YAP signaling pathway and the downstream target genes. miR-187 targeted PDLIM1, while miR-187 overexpression cramped PDLIM1 expression. The rescue experiment suggested that PDLIM1 overexpression weakened the procancer function of miR-187 in GC cells. In conclusion, our study demonstrated that PDLIM1 presented a low expression in GC tissues, while miR-187/PDLIM1 participated in GC development and cisplatin sensitivity by mediating the Hippo-YAP signaling pathway.

A new biomarker for the early diagnosis of gastric cancer: gastric juice- and serum-derived SNCG

Aim: To explore the possibility of gastric juice (GJ)- and serum-derived SNCG as a potential biomarker for the early diagnosis of gastric cancer (GC). Materials & methods: GJ and serum samples were collected from 87 patients with GC, 38 patients with gastric precancerous lesions and 44 healthy volunteers. The levels of SNCG in GJ and serum samples were detected by ELISA. Results: The levels of SNCG in GJ and serum were significantly higher in the GC group when compared with the GPL group or the control group. The expression of SNCG in GJ and serum was associated with tumor node metastasis stage, lymph node metastasis, tumor size and drinking, and it is important for the diagnosis and prognosis of GC (p < 0.05). Conclusion: The findings highlight the significance of SNCG in GC diagnosis and prognosis and implicate SNCG as a promising candidate for GC treatment.

Identification by Bioinformatics Analysis of Potential Key Genes Related to the Progression and Prognosis of Gastric Cancer

Objective

Despite increasingly sophisticated medical technology, the prognosis of patients with advanced gastric cancer is still not objectively certain. Therefore, it is urgent to identify new diagnostic and prognostic biomarkers. To identify potential critical genes related to gastric cancer’s staging mechanism and to the prognosis of gastric cancer.

Methods

Dynamic trend analysis was conducted to find genes with similar trends in gastric cancer staging in order to explore the differentially expressed genes in gastric cancer and identify the intersection of the results of the dynamic trend analysis. Functional predictive analysis were performed on the obtained genes to observe the expression of prognostic genes in gastric cancer and in gastric cancer stages as well as the correlation with tumor immune cell infiltration. Gastric cancer samples were collected and sequenced for follow-up analysis based on the results of the Cancer Genome Atlas (TCGA) database analysis.

Results

The expression of genes enriched in module 0 had a similar trend in gastric cancer staging. 3213 differential genes were screened. A total of 50 intersection genes were obtained among genes with similar trends, of which only 10 genes have prognostic significance in gastric cancer. These 10 genes were correlated with macrophage infiltration in varying degrees. In addition, we found that AGT was significantly abnormally expressed in the results of sample sequencing. AGT was related to the occurrence of gastric cancer and interacted with brd9, golph3, nom1, klhl25, and psmd11.

Conclusion

AGT has prominent abnormal expression in gastric cancer and may promote gastric cancer progression. This study provides a new direction for further exploring potential biomarkers and molecular targeted gastric cancer therapy.

Elucidating the Role of Serum tRF-31-U5YKFN8DYDZDD as a Novel Diagnostic Biomarker in Gastric Cancer (GC)

Background

Gastric cancer (GC) is one of the malignant tumors with the highest morbidity and mortality in the world. Early diagnosis combined with surgical treatment can significantly improve the prognosis of patients. Therefore, it is urgent to seek higher sensitivity and specificity biomarkers in GC. tRNA-derived small RNAs are a new non-coding small RNA that widely exists in tumor cells and body fluids. In this study, we explore the expression and biological significance of tRNA-derived small RNAs in GC.

Materials and Methods

First of all, we screened the differentially expressed tRNA-derived small RNAs in tumor tissues by high-throughput sequencing. Agarose gel electrophoresis (AGE), Sanger sequencing, and Nuclear and Cytoplasmic RNA Separation Assay were used to screen tRF-31-U5YKFN8DYDZDD as a potential tumor biomarker for the diagnosis of GC. Then, we detected the different expressions of tRF-31-U5YKFN8DYDZDD in 24 pairs of GC and paracancerous tissues, the serum of 111 GC patients at first diagnosis, 89 normal subjects, 48 superficial gastritis patients, and 28 postoperative GC patients by quantitative real-time PCR (qRT-PCR). Finally, we used the receiver operating characteristic (ROC) curve to analyze its diagnostic efficacy.

Results

The expression of tRF-31-U5YKFN8DYDZDD has good stability and easy detection. tRF-31-U5YKFN8DYDZDD was highly expressed in tumor tissue, serum, and cell lines of GC, and the expression was significantly related to TNM stage, depth of tumor invasion, lymph node metastasis, and vascular invasion. The expression of serum tRF-31-U5YKFN8DYDZDD in the GC patients decreased after the operation (P = 0.0003). Combined with ROC curve analysis, tRF-31-U5YKFN8DYDZDD has better detection efficiency than conventional markers.

Conclusions

The expressions of tRF-31-U5YKFN8DYDZDD in the tumor and paracancerous tissues, the serum of GC patients and healthy people, and the serum of GC patients before and after operation were different. tRF-31-U5YKFN8DYDZDD is not only a diagnostic biomarker of GC but also a predictor of poor prognosis.

Upregulated circRNA_102231 promotes gastric cancer progression and its clinical significance

Circular RNAs (circRNAs) are a type of endogenous non-coding RNAs implicated in cancer progression. This study explored the expression levels, clinical implication and possible molecular mechanism of circRNA_102231 in gastric cancer (GC). Gene Expression Omnibus (GEO) was used to analyze differentially expressed circRNAs. CircRNA_102231 expression was verified by qRT-PCR in GC tissues and plasma. The effects of circRNA_102231 was tested by CCK-8, colony formation, EdU and Transwell assays and xenograft tumor model. RNA pull-down and immunoprecipitation (RIP) assays were used to analyze the interaction between circRNA_102231 and IRTKS. CircRNA_102231 expression was significantly upregulated in GC tissue and plasma samples, which can be used as a biomarker for GC diagnosis and prognosis. The function assays showed that circRNA_102231 knockdown inhibited GC cell proliferation and invasion both in vitro and in vivo. CircRNA_102231 was able to bind to IRTKS, increasing IRTKS protein stability, leading to GC progression. Overexpression of IRTKS effectively rescued the reduced cell viability and invasion caused by silencing of circRNA_102231. In sum, our data demonstrate that circRNA_102231 is a novel oncogene in GC and acts as a potential biomarker and therapeutic target for GC patients.

Abbreviations

circRNAs: circular RNAs; GC: gastric cancer; GEO: Gene Expression Omnibus; RIP: RNA immunoprecipitation; DEGs: differentially expressed genes

MRPS17 promotes invasion and metastasis through PI3K/AKT signal pathway and could be potential prognostic marker for gastric cancer

In this study, the molecular mechanisms through which Mitochondrial Ribosomal Protein S17 (MRPS17) contributes to gastric cancer (GC) and its prognostic significance in GC have been explored. As a protein encoding gene, MRPS17 encodes a 28s proteins belonging the ribosomal protein S17P family. The specific roles and molecular mechanisms of MRPS17 in cancers remain ambiguous. It was revealed by analyzing data from TCGA and GEO that elevated expression of MRPS17 was significantly associated with invasion of GC and poor survival of GC patients. Then through univariate and multivariate Cox regression analyses it was demonstrated that MRPS17 an independent prognostic factor for GC patients (P<0.001). It was demonstrated by differentially expressed gene analysis and functional enrichment analysis that MPRS17 is related to PI3K/AKT pathway and Cell adhesion molecules (CAMs), while its function is mediated by collagen-containing extracellular matrix and receptor ligand/regulator activity. Then it was proven by in-vitro experiments that knocking down of MRPS17 gene in AGS and SGC7901 cells would significantly inhibit proliferation and invasion capability of these cells. Furthermore, it was revealed by cell immunofluorescence assay that as a ribosomalprotein, MRPS17 was mainly distributed in the cytoplasmic surface of cell membrane. Additionally, activation of PI3K/AKT pathway is responsible for malignant progression of glioma that was promoted by MRPS17.

In conclusion, it was revealed in the present study that MRPS17 promoted invasion and metastasis of GC and potential molecular mechanisms through which it exerted its influences on GC were explored, suggesting its potential as a novel prognostic biomarker for GC.

A Network Pharmacological Approach to Reveal the Pharmacological Targets and Its Associated Biological Mechanisms of Prunetin-5-O-Glucoside against Gastric Cancer

Simple Summary

Identification of pharmacological targets in cancer provides a major walkthrough toward treatment strategies. The present research adopted a network pharmacology approach utilizing a flavonoid glucoside prunetin-5-O-glucoside (PG) compound against gastric cancer. The correlative targets were analyzed using Swiss target prediction and DiGeNET databases. Functional enrichment and significant pathways enriched were predicted for the targets to associate its biological mechanisms with cancer. Protein interaction network and cluster analysis was performed using Search Tool for the Retrieval of Interacting Genes/Proteins (STRING). Our analysis revealed three core targets among the clustered modules that plays a crucial role in relation with cancer. With this information, the core targets were examined for the binding affinity with PG using molecular docking analysis and validations on the protein targets was performed using western blot analysis and Human Protein Atlas. Our analysis through comprehensive network pharmacology resulted in the prediction of three core targets of PG that can be significant biomarkers against gastric cancer.

Abstract

Gastric cancer (GC) is an aggressive malignancy with increased mortality rate and low treatment options. Increasing evidence suggests that network pharmacology will be a novel method for identifying the systemic mechanism of therapeutic compounds in diseases like cancer. The current study aimed to use a network pharmacology approach to establish the predictive targets of prunetin-5-O-glucoside (PG) against gastric cancer and elucidate its biological mechanisms. Primarily, genes associated with the pathogenesis of GC was identified from the DiGeNET database and targets of PG was obtained from the Swiss target prediction database. In total, 65 correlative hits were identified as anti-gastric cancer targets of PG. Functional enrichment and pathway analysis revealed significant biological mechanisms of the targets. Interaction of protein network and cluster analysis using STRING resulted in three crucial interacting hub targets namely, HSP90AA1, CDK2, and MMP1. Additionally, the in vitro cytotoxic potential of PG was assessed on three gastric cancer cells (AGS, MKN-28, and SNU-484). Furthermore, the crucial targets were validated using molecular docking, followed by their expressions being evaluated by western blot and Human Protein Atlas. The findings indicate that the pharmacological action of PG against GC might be associated with the regulation of three core targets: HSP90AA1, CDK2, and MMP1. Thus, the network pharmacology undertaken in the current study established the core active targets of PG, which may be extensively applied with further validations for treatment in GC.

miR-6838-5p Affects Cell Growth, Migration, and Invasion by Targeting GPRIN3 via the Wnt/β-Catenin Signaling Pathway in Gastric Cancer

Gastric cancer (GC) is a highly prevalent digestive malignant tumor, ranking second in the tumor-related mortality globally. The microRNAs have been confirmed to be connected with GC progression. Accumulative evidence has suggested that miR-6838-5p exerts a suppressive effect on human cancers. Nonetheless, whether miR-6838-5p is involved in the regulation of GC remains to be investigated. During our research, miR-6838-5p was downregulated in GC cells. Upregulated miR-6838-5p repressed GC cell cycle progression, proliferation, migration, and invasion. Furthermore, miR-6838-5p overexpression repressed the nuclear import of β-catenin, thus inactivating Wnt/β-catenin pathway. Moreover, we observed that GPRIN3 was targeted by miR-6838-5p in GC with luciferase reporter and RIP assays. GPRIN3 upregulation reversed the suppression of miR-6838-5p in GC cellular processes. These findings suggest miR-6838-5p restrains the malignant behaviors of GC cells via targeting GPRIN3 to repress Wnt/β-catenin signaling pathway, which may provide novel targets for GC treatment.

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.