Biomarkers of gastric cancer: Current topics and future perspective

The molecular mechanisms of Caulophyllum robustum Maxim extract inhibition by regulating FAK/PI3K signaling pathway in gastric cancer HGC-27 cells

ETHNOPHARMACOLOGICAL RELEVANCE

Caulophyllumrobustum Maxim extract (CRME), as recorded in traditional Chinese medicine, has the function of dispelling Feng, regulating Qi and dredging collaterals, promoting blood circulation and regulating menstruation, gingering up and relieving pain, clearing heat simultaneously detoxifying, lowering blood pressure and hemostasis. CRME is often used as Chinese materia medica preparation for rheumatoid arthritis, traumatic injury, irregular menstruation, abdominal pain, and hypertension treatment. Since gastric cancer (GC) existed as a health problem of human over the years, we are committed to the development of potential components of Chinese herbal medicine curing cancer, and we found CRME is expected to be one of the effective anti-tumor traditional Chinese medicine preparations.

AIMS OF THE STUDY

To investigate the molecular mechanisms of CRME anticancer effects and the potential links between CRME and FAK.

MATERIALS AND METHODS

Caulophyllumrobustum Maxim was extracted to obtain CRME, high-performance liquid chromatography (HPLC) was used for qualitative analysis. Information about CRME was collected from traditional Chinese medicine records and local surveys unpublished internationally. Series of cellular function experiments were applied to detect cell proliferation, migration, apoptosis, autophagy, cell cycle, angiogenesis. The xenograft model is employed in vivo.

RESULTS

CRME can significantly inhibit HGC-27 cells on proliferation, migration and angiogenic capacity. Xenograft model indicated CRME inhibited cell proliferation in vivo. Annexin V-FITC/PI double staining assay and PI single staining assay depicted that CRME induces cell apoptosis, and arrests cell cycle at G0/G1 phase. AO (acridine orange) staining assay showed that CRME promoted autophagosome formation and inhibited autophagic flow. HPLC indicated Cauloside A and Cauloside C are components of CRME. Western blot indicated that FAK/PI3K signaling pathway is critical in the inhibition of CRME on HGC-27 cells.

CONCLUSIONS

The anti-tumor components of CRME, Cauloside A and Cauloside C, inhibited tumor progression in HGC-27 cells. This inhibition is achieved by decreasing the phosphorylation levels of FAK, thereby modulating PI3K/AKT signaling pathway.

Electrochemical immunoassay for gastric cancer biomarker pepsinogen I detection based on PdAgPt/MoS2

This study presents a novel electrochemical immunosensor for the detection of pepsinogen I, a potential biomarker for gastric cancer, based on a unique PdAgPt/MoS2nanocomposite. The key innovation lies in the synergistic combination of trimetallic PdAgPt nanoparticles with MoS2nanoflowers, which has not been previously reported for pepsinogen I detection. This hybrid material demonstrates exceptional electron transfer properties and a significantly larger electroactive surface area compared to conventional materials. The optimized immunosensor exhibits superior performance metrics: a wide linear range of 0.5-200 ng ml-1and an unprecedented low detection limit of 0.173 ng ml-1, surpassing existing detection methods. The sensor shows remarkable selectivity with interfering substances exhibiting relative responses below 5%, excellent reproducibility (RSD 3.8%), and outstanding stability (95.6% retention after 30 d). Analysis of spiked serum samples resulted in recoveries ranging from 96.8% to 104.5%, demonstrating the sensor's practical applicability for early gastric cancer screening. This work represents a significant advancement in developing rapid, sensitive, and cost-effective diagnostic tools for gastric cancer surveillance.

Role of ITGB2 protein structure and molecular mechanism in precancerous lesions of gastric cancer: Influencing the occurrence and development of cancer through the CXCL1-CXCR2 axis

Gastric cancer is a prevalent gastrointestinal tumor. In the classical cascade of gastric cancer development, the gradual progression from non-atrophic gastritis, atrophic gastritis, intestinal metaplasia, to intraepithelial neoplasia eventually leads to early gastric cancer. We investigated the proteomic characteristics of chronic gastritis (CG), low-grade intraepithelial neoplasia (low-grade LGIN), and early gastric cancer (EGC). Additionally, we utilized transcriptomic databases to explore the expression patterns of ITGB2 across different stages of gastric tissue and its correlation with the prognosis of gastric cancer. The expression of ITGB2 was confirmed in cytological experiments, revealing that ITGB2 can influence the onset and progression of gastric cancer via the CXCL1-CXCR2 axis. This finding suggests that ITGB2 represents a novel biomarker for gastric cancer, making it a potential target for accurate diagnosis and treatment.

Brasiliensic acid: in vitro cytotoxic and genotoxic, in vivo acute toxicity and in silico pharmacological prediction of a new promising molecule

Brasiliensic acid (Bras) is a chromanone isolated from Calophyllum brasiliense Cambèss. bark extracts with confirmed potential activity on gastric ulcer and Helicobacter pylori infection. This study aimed to investigate the in vitro and in vivo toxicity of Bras and molecular docking studies on its interactions with the H. pylori virulence factors and selected gastric cancer-related proteins. Cytotoxicity was evaluated by alamarBlue© assay, genotoxicity by micronucleus and comet assays, and on cell cycle by flow cytometry, using Chinese hamster epithelial ovary cells. Bras was not cytotoxic to CHO-K1 cells, and caused no chromosomal aberrations, nor altered DNA integrity. Furthermore, Bras inhibited damages to DNA by H2O2 at 1.16 µM. No cell cycle arrest was observed, but apoptosis accounted for 31.2% of the cell death observed in the CHO-K1 at 24 h incubation of the IC50. Oral acute toxicity by Hippocratic screening test in mice showed no relevant behavioral change/mortality seen up to 1,000 mg/kg. The molecular docking approach indicated potential interactions between Bras and the various targets for peptic ulcer and gastric cancer, notably CagA virulence factor of H. pylori and VEGFR-2. In conclusion, Bras is apparently safe and an optimization for Bras can be considered for gastric ulcer and cancer.Communicated by Ramaswamy H. Sarma.

Dysregulated transfer RNA-derived small RNAs as potential gastric cancer biomarkers

Gastric cancer (GC) is the kind of carcinoma that has the highest rates of morbidity and death worldwide. In the early stages of GC, there is currently an absence of sensitive and specific biomarkers. The newly-discovered class of non-coding RNAs (ncRNAs) known as transfer RNA-derived small RNAs (tsRNAs) is highly expressed in bodily fluids and neoplastic cells. High-throughput sequencing was initially employed to identify differentially expressed tsRNAs in early GC patients, followed by validation in patient serum, GC tissues, and cell lines by quantitative real-time polymerase chain reaction (qRT-PCR). We identified dysregulated tsRNAs (the up-regulated tsRNAs included tRF-31-PNR8YP9LON4VD, tRF-30-MIF91SS2P4FI, and tRF-30-IK9NJ4S2I7L7, whereas the down-regulated tsRNAs included tRF-38-W6RM7KYUPRENRHD2, tRF-37-LBRY73W0K5KKOV2, tRF-36-JB59V3WD8YQ84VD, tRF-25-MBQ4NKKQBR, and tRF-36-0KFMNKYUHRF867D) in GC, and we verified that the serum of patients, GC cells and tissues both consistently expressed these tsRNAs. Additionally, GC patients' serum had considerably greater expression levels of the three up-regulated tsRNAs than did healthy controls. Receiver operating characteristic (ROC) curve analysis demonstrated that the sensitivity and specificity of the three up-regulated tsRNAs were superior to those of CEA, CA199, and CA724 in the process of diagnosing GC, particularly in its early stages. This suggests that tsRNAs have great diagnostic efficacy and potential as new "liquid biopsy" biomarkers for the diagnosis of GC. Using bioinformatics software, we predicted that dysregulation of tsRNAs may be a potential regulatory mechanism for the development of GC.

Potential Probes for Targeted Intraoperative Fluorescence Imaging in Gastric Cancer

Gastric cancer (GC) is a malignant tumor of the gastrointestinal tract associated with high mortality rates and accounting for approximately 1 million new cases diagnosed annually. Surgery, particularly radical gastrectomy, remains the primary treatment; however, there are currently no specific approaches to better distinguish malignant from healthy tissue or to differentiate between metastatic and non-metastatic lymph nodes. As a result, surgeons have to remove all lymph nodes indiscriminately, increasing intraoperative risks for patients and prolonging hospital stay. Near-infrared fluorescence imaging with indocyanine green (ICG) can provide real-time visualization of the surgical field using both conventional laparoscopy and robotic mini-invasive precision surgery platforms. However, its application shows some limits, as ICG is a non-targeted contrast agent. Several studies are now investigating the potential efficacy of fluorescent targeted agents that could selectively bind to the tumor tissue, offering a valuable tool for metastatic mapping during robotic gastrectomy. This review aims to summarize the key fluorescent agents that have been developed to recognize GC markers, as well as those targeting the tumor microenvironment (TME) and metabolic features. These agents hold great potential as valuable tools for enhancing precision surgery in robotic gastrectomy procedures improving the clinical recovery of GC patients.

Identification of gastric cancer biomarkers through in-silico analysis of microarray based datasets

Gastric cancer is among the most prevalent cancers worldwide including in Pakistan. Late diagnosis of gastric cancer leads to reduced survival. The present study aimed to investigate biomarkers for early diagnosis and prognosis of gastric cancer. For this purpose, the ten microarray-based gene expression datasets (GSE54129, GSE79973, GSE161533, GSE103236, GSE33651, GSE19826, GSE118916, GSE112369, GSE13911, and GSE81948) were retrieved from GEO database and analyzed by GEO2R to identify differentially expressed genes. Datasets were arranged in subsets of different dataset combinations to identify common DEGs. The gene ontology and functional pathway enrichment analysis of common DEGs was performed by DAVID tool. Pan-cancer analysis was conducted by UALCAN database. Survival analysis of common DEGs was done by Kaplan-Meier plotter. A total of 71 common DEGs were identified in different combinations of datasets. Among them, only 5 DEGs namely ATP4B, ATP4A, CCKBR, KCNJ15, and KCNJ16 were detected to be common in all the datasets. The GO and pathway analysis represented that the identified DEGs are involved in gastric acid secretion and collecting duct acid secretion pathways. Further expression validation of these five genes using three additional datasets (GSE31811, GSE26899, and GSE26272) confirmed their differential expression in gastric cancer samples. The pan-cancer analysis also revealed aberrant expression of DEGs in various cancers. The survival analysis showed the association of these 5 DEGs with poor survival of gastric cancer patients. To conclude, this study revealed a panel of 5 genes, which can be employed as diagnostic and prognostic biomarkers of gastric cancer patients.

The potential of circular RNAs as biomarkers and therapeutic targets for gastric cancer: A comprehensive review

BACKGROUND

Gastric cancer (GC) is a global health concern, contributing significantly to cancer-related mortality rates. Early detection is vital for improving patient outcomes. Recently, circular RNAs (circRNAs) have emerged as crucial players in the development and progression of various cancers, including GC.

AIM

This comprehensive review underscores the promising potential of circRNAs as innovative biomarkers for the early diagnosis of GC, as well as their possible utility as therapeutic targets for this life-threatening disease. Specifically, the review focuses on recent findings, mechanistic insights, and clinical applications of circRNAs in GC.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Dysregulation of circRNAs has been consistently observed in GC tissues, offering potential diagnostic value due to their stability in bodily fluids such as blood and urine. For instance, circPTPN22 and hsa_circ_000200. Furthermore, the expression levels of circRNAs such as circCUL2, hsa_circ_0000705 and circSHKBP1 have shown strong associations with critical clinical features of GC, including diagnosis, prognosis, tumor size, lymph node metastasis, tumor-node-metastasis (TNM) stage, and treatment response. Additionally, circRNAs such as circBGN, circLMO7, and circMAP7D1 have shown interactions with specific microRNAs (miRNAs), proteins, and other molecules that play key roles in development and progression of GC. This further highlighting their potential as therapeutic targets. Despite their potential, several challenges need to be addressed to effectively apply circRNAs as GC biomarkers. These include standardizing detection methods, establishing cutoff values for diagnostic accuracy, and validating findings in larger patient cohorts. Moreover, the functional mechanisms by which circRNAs contribute to GC pathogenesis and therapeutic resistance warrant further investigation. Advances in circRNAs research could provide valuable insights into the early detection and targeted treatment of GC, ultimately improving patient outcomes.

Establishment and validation of a nomogram model for early diagnosis of gastric cancer: a large-scale cohort study

Purpose

Identifying high-risk populations and diagnosing gastric cancer (GC) early remains challenging. This study aimed to establish and verify a nomogram model for the early diagnosis of GC based on conventional laboratory indicators.

Methods

We performed a retrospective analysis of the clinical data of 2,770 individuals with first diagnosis of GC and 1,513 patients with benign gastric disease from January 2018 to December 2022. The cases were divided into the training set and validation set randomly, with a ratio of 7:3. Variable screening was performed by least absolute shrinkage and selection operator (LASSO) and logistic regression analysis. A nomogram was constructed in the training set to assist in the early diagnosis of GC.

Results

There were 4283 patients included in the study, with 2998 patients assigned in the training set and 1285 patients in the validation set. Through LASSO regression and logistic regression analysis, independent variables associated with GC were identified, including CEA, CA199, LYM, HGB, MCH, MCHC, PLT, ALB, TG, HDL, and AFR. The nomogram model was constructed using the above 11 independent indicators. The AUC was 0.803 for the training set and 0.797 for the validation set, indicating that the model showed high clinical diagnostic efficacy. The calibration curves and decision curve analysis (DCA) of the nomogram presented good calibration and clinical application ability.

Conclusion

Based on the analysis of large sample size, we constructed a nomogram model with 11 routine laboratory indicators, which showed good discrimination ability and calibration.

The regulatory role of tRNA-derived small RNAs in the prognosis of gastric cancer

In recent years, tRNA-derived small RNAs (tsRNAs) including tRNA-derived stress-induced RNAs (tiRNAs) and tRNA-derived fragments (tRFs), with specific structure and enriched in body fluids, have been found to have specific biological functions. In this paper, the biogenesis, classification, subcellular localization, and biological functions of tsRNAs were summarized. It has been proved that tsRNAs affected tumor cells in proliferation, apoptosis, migration and invasion, and played roles in regulating the occurrence and development of various tumors. In gastric cancer (GC), the imbalance of tsRNAs, such as tRF-33-P4R8YP9LON4VDP, tRF-17-WS7K092, tRF-23-Q99P9P9NDD and others, was closely related to the clinicopathological characteristics of GC patients. Some tsRNAs, such as tRF-23-Q99P9P9NDD, tRF-31-U5YKFN8DYDZDD, and tRF-27-FDXXE6XRK45 promoted the proliferation, migration and invasion of GC cells. Other tsRNAs, such as tRF-41-YDLBRY73W0K5KKOVD, tRF-18-79MP9PO4, and tRF-Glu-TTC-027 inhibited the proliferation, migration and invasion of GC cells. The tsRNAs played roles in the occurrence of GC were through several signaling pathways, such as phosphoinositide 3-kinase (PI3K)-AKT serine/threonine kinase (AKT), Wnt-β-Catenin, and mitogen-activated protein kinase (MAPK) pathways. These findings may provide new strategies for the diagnosis and treatment of GC.

Best-Practice Biomarker Testing of Oesophago-Gastric Cancer in the UK: Expert Consensus Recommendations Developed Using a Modified Delphi

AIMS

Oesophago-gastric cancers (OGCs) are amongst the most commonly diagnosed malignancies worldwide and are associated with high disease-related mortality. Predictive biomarkers are molecules that can be objectively measured and used to indicate a likely response to therapeutic intervention, thus facilitating individualised cancer therapy. However, there remains variation in uptake and implementation of biomarker testing across the UK.

MATERIALS AND METHODS

We conducted a modified Delphi study to formulate consensus recommendations for best-practice biomarker testing of OGC in the UK. We employed two rounds of online questionnaires followed by a virtual consensus meeting. Biomarkers for discussion included HER2, MSI/MMR, and PD-L1. Topics comprised the overall biomarker pathway, pre-analytical, analytical, and post-analytical considerations, including challenges in current practice.

RESULTS

Twenty-six and eighteen participants completed the first and second round Delphi questionnaire, respectively, with an even split of pathologists and oncologists from across the UK. There was consensus (>80% agreement) across several topics, including the requirements for standardisation of the pathway, which must include coordination throughout the tissue journey, requirements for a quality-assured process to ensure accuracy and validity of testing, plus the need for clear, detailed information on the pathology report to support treatment decisions. There was consensus amongst oncologists regarding reflex testing of all biomarkers depending on histology; however, concerns over capacity in relation to workload and availability of pathologists were evident among the pathologists. Overall, participants were in the opinion that reflex testing improves the speed of treatment decisions and improves patient care.

CONCLUSION

The recommendations reflect best-practices and should be implemented to support rapid multidisciplinary team decision-making within oesophago-gastric cancer. Results reflect the need for standardisation and demonstrate the challenges faced in clinical practice by those requesting and testing biomarkers for oesophago-gastric cancer, suggesting significant concerns relating to pathologist capacity.

The implicated role of GDF15 in gastrointestinal cancer

BACKGROUND

Growth differentiation factor 15 (GDF15), a stress-responsive cytokine from transforming growth factor superfamily, is highly expressed in mammalian tissues, including pancreas, stomach and intestine under pathological conditions. In particular, elevated levels of GDF15 might play an important role in the development and progression of various gastrointestinal cancers (GCs), suggesting its potential as a promising target for disease prediction and treatment.

METHODS

In this review, systematic reviews addressing the role of GDF15 in GCs were updated, along with the latest clinical trials focussing on the GDF15-associated digestive malignancies.

RESULTS

The multiple cellular pathways through which GDF15 is involved in the regulation of physiological and pathological conditions were first summarized. Then, GDF15 was also established as a valuable clinical index, functioning as a predictive marker in diverse GCs. Notably, latest clinical treatments targeting GDF15 were also highlighted, demonstrating its promising potential in mitigating and curing digestive malignancies.

CONCLUSIONS

This review unveils the pivotal roles of GDF15 and its potential as a promising target in the pathogenesis of GCs, which may provide insightful directions for future investigations.

Clinicopathological and prognostic significance of TIMP1 expression in gastric cancer: a systematic review and meta-analysis

BACKGROUND

The research on the associations between tissue inhibitors of metalloproteinase-1 (TIMP1) expression and the clinicopathological characteristics and prognosis of patients with gastric cancer (GC) have resulted in contradictory findings. Exploring the associations between TIMP1 and clinicopathological parameters and the prognosis of GC patients is essential.

METHODS

We searched the literature in the databases according to the inclusion and exclusion criteria. Hazard ratios (HRs), odds ratios (ORs) and 95% confidence intervals (95% CIs) were used to evaluate the relationships between TIMP1 expression and the clinicopathological parameters and prognosis of GC patients.

RESULTS

Nine studies with 1,200 GC patients were included. Our results indicated that TIMP1 expression was not related to sex, age, TNM stage, depth of invasion, lymph node metastasis, or tumor size in GC patients. However, TIMP1 expression was associated with the differentiation of GC. Furthermore, TIMP1 expression was associated with poor prognosis in GC patients.

CONCLUSION

TIMP1 expression was related to tumor differentiation and poor prognosis but not sex, age, TNM stage, depth of invasion, lymph node metastasis or tumor size.

Identification and validation of a novel innate lymphoid cell-based signature to predict prognosis and immune response in liver cancer by integrated single-cell RNA analysis and bulk RNA sequencing

Background

Innate lymphoid cells (ILCs) exert tumor suppressive and tumor promoting effects. However, the prognostic significance of ILC-associated genes remains unclear in hepatocellular carcinoma (HCC). Hence, the aim of this research was to develop an innovative predictive risk classification system using bioinformatics examination.

Methods

We explored the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases to gather data pertaining to HCC and its clinical details. Significantly different ILC-associated genes were investigated by Seurat analysis. The number of signaling interactions of ILCs with other cells was discovered by CellPhoneDB analysis. ClusterProfiler and Metascape were utilized to perform Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses on ILC genes. In order to identify potential ILC predictors, we utilized univariate Cox regression and least absolute shrinkage and selection operator (LASSO) analyses, subsequently validating these predictors in TCGA and GEO groups. The multi-omics ILC signature model's clinical predictive capabilities, along with drug sensitivity and immune factor relations, were assessed using Cell-type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) and pRRophetic. We investigated the possible molecular pathways in our predictive ILC signature through the utilization of gene set enrichment analysis (GSEA) and gene set variation analysis (GSVA). Five key genes were screened out by constructing a competing endogenous RNA (ceRNA) network using Cytoscape and their values in clinical indexes were demonstrated. Immunohistochemistry (IHC) in HCC cases confirmed the expression of these genes.

Results

ILC cell subsets were identified, and cell-cell communication analysis revealed that the signaling pathways involving ILC cell subsets were mostly abundant in the HCC microenvironment. Subsequently, 270 marker genes of the ILC clusters were subjected to GO and KEGG enrichment analysis. Furthermore, a total of 58 prognostically relevant genes were screened as features for prognostic prediction models. Next, the models were validated and clinically evaluated (P values of Kaplan-Meier survival curves below 0.05). Five key genes (C2, STK4, CALM1, IL7R, and RORA) were further screened by multi omics analysis of immune cell and factor and drug sensitivity and correlation analysis of tumor regulatory genes in liver cancer. Furthermore, the potential clinical value of the 5 key genes was confirmed in HCC patients. Finally, the IHC results confirmed the expression of C2, STK4, CALM1, IL7R, and RORA in HCC. Our experimental results provided preliminary evidence supporting the oncogenic roles of STK4 and CALM1, as well as the tumor-suppressive roles of C2, RORA, and IL7R in HCC.

Conclusions

A novel prognostic feature of ILC potentially involved in HCC was discovered. It showed high values in predicting patient overall survival (OS) as well as good differences in immunity and drug sensitivity. Therefore, targeting these ILC signatures may be a potential effective approach in HCC treatment.