Development Of Gastric Cancer Research Articles

CircTSN promotes the proliferation and metastasis of gastric cancer through the miR-1825/SLC38A2 signaling axis.

Comprehensive treatment of gastric cancer (GC) is progressing, but the rapid proliferation and metastasis of GC remains a cause of high recurrence and mortality rates. In this study we investigated GC-associated circRNA tending to yield more insight into the mechanisms of gastric cancer development. We detected the expression levels of circTSN in GC tissues and cell lines using qRT-PCR. The circular structure of circTSN was confirmed by Sanger sequencing, agarose gel electrophoresis and RNase R. A series of cell functional experiments were employed to investigate the implication of circTSN aberrant expression on the proliferation and metastasis of GC cells. The predicted binding domain between circTSN and miR-1825 was analyzed by luciferase reporter gene analysis. Meanwhile, subcutaneous tumor xenografts in nude mice were used to validate the role of circTSN in vivo. It was found that RNA levels of circTSN were significantly elevated in GC tissues and cell lines, which was also confirmed to contain a closed-loop structure. CCK8, clone formation, EdU, transwell and in vivo experiments indicated that the highly expressed circTSN was involved in the proliferation and metastasis process of GC. In addition, circTSN modulates the expression of SLC38A2 by sequence-specific binding to miR-1825. This study identified that circTSN, which is highly expressed in GC, was able to contribute to the proliferation and metastasis of GC cell through miR-1825/SLC38A2 axis and this might provide a new candidate target for the precision treatment of GC.

Risk Factors for Gastric Cancer at RSUP Prof. Dr. I.G.N.G. Ngoerah Year 2018-2023

Gastric cancer is the fifth most common cancer and the fourth most common cause of death due to cancer in the world. The development of gastric cancer tends to be quite slow and takes years, so it is often found in the late stages. The cause of stomach cancer is not known for certain, but it is believed to be caused by many factors. This study aims to determine the risk factors for gastric cancer at RSUP Prof. Dr. I.G.N.G. Ngoerah was diagnosed in 2018-2023. This research was conducted using a retrospective descriptive method using secondary data in the form of medical records on 46 samples of gastric cancer patients who were controls or treated at RSUP Prof. Dr. I.G.N.G. Ngoerah was diagnosed in 2018-2023 The variables studied include the dependent variables, namely age, gender, peptic ulcers, blood type, obesity, alcohol consumption and smoking. The results of the analysis showed that gastric cancer patients at RSUP Prof. Dr. I.G.N.G. The majority are over 50 years old (82.6%), male (58.7%), have no peptic ulcers (89.1%), have blood type A (37%), underweight (50%), are not consume alcohol (97.8%), and do not smoke (97.8%).It can be concluded that the risk factors for gastric cancer patients at RSUP Prof. Dr. I.G.N.G. Ngoerah majority are over 50 years old, male, have no peptic ulcers, have blood type A, are underweight, do not consume alcohol and do not smoke. Keywords: Gastric Cancer, Risk Factors, RSUP Prof. Dr. I.G.N.G. Ngoerah

Mutational Landscape of Gastric Adenocarcinoma of the Fundic Gland Type Revealed by Whole Genome Sequencing.

Gastric adenocarcinoma of the fundic gland type (GA-FG) is a newly described variant of gastric adenocarcinoma with lack of knowledges regarding its genetic features. We performed whole-genome sequencing (WGS) in formalin-fixed paraffin-embedded (FFPE) tumor tissues and matched adjacent noncancerous specimens from 21 patients with GA-FG, and integrated published datasets from 1105 patients with traditional gastric adenocarcinoma with the purpose of dissecting genetic determinants both common to conventional gastric adenocarcinoma and unique to GA-FG disease. We characterized the genomic architecture of GA-FG disease, revealing the predominant proportion of C > T substitution among the six types of SNVs. GNAS was the most significantly mutated driver gene (14.29%). 42.8% of samples harbored "Kataegis." Distinct genomic alterations between GA-FG and conventional gastric cancer were identified. Specifically, low mutational burden and relatively moderate mutational frequencies of significantly mutated driver genes, coupled with the absence of non-silent alterations of formerly well-known drivers such as TP53, PIK3CA and KRAS were identified in GA-FG patients. Oncogenic signaling pathway analysis revealed mutational processes associated with focal adhesions and proteoglycans in cancer, highlighting both common and specific procedures during the development of GA-FG and conventional gastric cancer. Our study is the first to comprehensively depict the genomic landscape highlighting the multidimensional perturbations in GA-FG patients. These discoveries offered mechanistic insights for novel diagnostic and therapeutic strategies for patients with such disease.

Host repair polymorphisms and H. pylori genes in gastric disease outcomes: Who are the guardian and villains?

Gastric cancer (GC) is the fourth-leading cause of cancer-related mortality. The intestinal subtype of GC comes after the cascade of Correa, presenting H. pylori infection as the major etiological factor. One of the main mechanisms proposed for the progression from a more benign gastric lesion to cancer is DNA damage caused by chronic inflammation. Polymorphisms in DNA repair genes can lead to an imbalance of host DNA damage and repair, contributing to the development of GC. From there, we evaluated the risk of polymorphisms in DNA repair system genes in progressive gastric diseases and their association with the H. pylori genotype. This study included 504 patients from two public hospitals in Brazil’s north and northeast regions. The samples were classified into active and inactive gastritis, metaplasia, and GC. Polymorphisms in the DNA repair genes MLH1-93G > A, APE1 2197 T > G, XRCC1 28,152 G > A, MGMT 533 A > G, and XRCC3 18,067C > T were investigated by RFLP-PCR and H. pylori genotype by PCR. Statistical analyses were conducted using EPINFO 7.0., SNPSTAT, and CART software. The XRCC1 (GA) polymorphic allele stood out because it was associated with a lower risk of more severe gastric disease progression. Haplotypes of XRCC1 (GA) associated with some genotypes of MGMT, XRCC3, MLH1, and APE1 also showed protection against the progression of gastric diseases. XRCC3 (CT) showed a decreased risk of gastric disease progression in women, while a risk 1.3x to GC was observed in the MLH1 (A) polymorphic allele. The interaction between H. pylori genes and the host showed that the H. pylori cagE gene was the most important virulence factor associated with a worse clinical outcome, even overlapping with the XRCC1 polymorphism, where the MLH1 polymorphism response varied according to vacA alleles. Our results show the relevance of XRCC1 G > A for genome integrity, sex influence, and interaction between H. pylori virulence factors and XRCC1 and MLH1 genotypes for gastric lesion outcomes in Brazilian populations.

Impacts of Matrix Metalloproteinase-8 Genotypes, Smoking, Alcohol Drinking, and Helicobacter Pylori Infection on Gastric Cancer.

In gastric cancer (GCa) tissues, mRNA expression of matrix metalloproteinase-8 (MMP-8) is notably reduced compared to healthy tissues. Furthermore, abnormally low or elevated serum levels of MMP-8 have been linked to a significantly poor prognosis. The involvement of MMP-8 genotypes in susceptibility to GCa remains underexplored. We aimed to assess the influence of MMP-8 genotypes on GCa susceptibility and their potential interactions with smoking, alcohol consumption, and Helicobacter pylori (H. pylori) infection. The study utilized polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) to analyze MMP-8 rs11225395, rs34009635, and rs35866072 genotypes in 161 GCa patients and 483 controls. No statistically significant difference was detected in the distribution of genotypic (p for trend=0.3635) or allelic (p=0.1954) frequencies of MMP-8 rs11225395. Under a dominant model, combined CT+TT genotypes showed no association with GCa risk [odds ratio (OR)=0.77, 95% confidence interval (95%CI)=0.54-1.10, p=0.1852]. Similarly, no association was observed for MMP-8 rs34009635 or rs35866072. Importantly, individuals with the MMP-8 rs11225395 CC genotype demonstrated a significant increase in GCa risk when exposed to smoking (OR=4.04, 95%CI=2.28-7.16, p=0.0001), alcohol consumption (OR=2.83, 95%CI=1.64-4.89, p=0.0002), and H. pylori infection (OR=3.53, 95%CI=2.12-5.90, p=0.0001). The findings indicate that individuals carrying the MMP-8 rs11225395 CC genotype have increased susceptibility to GCa, especially when combined with risk factors, such as smoking, alcohol consumption, and H. pylori infection. These results suggest that MMP-8 genotype-based preventive strategies, including lifestyle alterations and targeted infection treatments, may be valuable in mitigating GCa development.

Effect of smoking on the risk of gastrointestinal cancer after cholecystectomy: A national population-based cohort study.

The role of smoking in the incidence of colorectal cancer (CRC) or gastric cancer (GC) in populations undergoing cholecystectomy has not been investigated. To evaluate the effect of smoking on CRC or GC development in cholecystectomy patients. A total of 174874 patients who underwent cholecystectomy between January 1, 2010 and December 31, 2017 were identified using the Korean National Health Insurance Service claims database. These patients were matched 1:1 with members of a healthy population according to age and sex. CRC or GC risk after cholecystectomy and the association between smoking and CRC or GC risk in cholecystectomy patients were evaluated using adjusted hazard ratios (HRs) and 95%CIs. The risks of CRC (adjusted HR: 1.15; 95%CI: 1.06-1.25; P = 0.0013) and GC (adjusted HR: 1.11; 95%CI: 1.01-1.22; P = 0.0027) were significantly higher in cholecystectomy patients. In the population who underwent cholecystectomy, both CRC and GC risk were higher in those who had smoked compared to those who had never smoked. For both cancers, the risk tended to increase in the order of non-smokers, ex-smokers, and current smokers. In addition, a positive correlation was observed between the amount of smoking and the risks of both CRC and GC. Careful follow-up and screening should be performed, focusing on the increased risk of gastrointestinal cancer in the cholecystectomy group, particularly considering the individual smoking habits.

Exosomal miR-502-5p suppresses the progression of gastric cancer by repressing angiogenesis through the Wnt/β-catenin pathway.

Gastric cancer (GC) is a significant global health concern, ranking as the fifth most common cancer and the third leading cause of cancer-related deaths. The role of miR-502-5p in various cancers has been studied, but its specific impact on gastric cancer through exosomes is not well understood. This study aimed to investigate the role and mechanism of exosome-derived miR-502-5p in gastric cancer. Differential expression of miR-502-5p in tissues or serum of GC patients was determined using qRT-PCR. The impact of miR-502-5p on cell proliferation, migration, and invasion was assessed through in vitro and in vivo experiments. The potential of exosome-miR-502-5p to inhibit metastatic ability was also explored by using vivo and vitro assay. Furthermore, the underlying mechanism of miR-502-5p in gastric cancer was investigated using western blotting. It was found that miR-502-5p suppressed the proliferation, migration, and invasion of gastric cancer cells. Exosome-miR-502-5p expression was negatively linked to metastatic ability and demonstrated inhibition of metastasis in vitro and in vivo. Additionally, miR-502-5p appeared to inhibit angiogenesis through the Wnt/β-catenin pathway in gastric cancer. Exosomal miR-502-5p acts as a suppressor in the development and progression of gastric cancer, suggesting its potential as a target for anti-cancer therapy or as a diagnostic biomarker.

Fusobacterium nucleatum: Unraveling its potential role in gastric carcinogenesis.

Fusobacterium nucleatum (F. nucleatum) is a Gram-negative anaerobic bacterium that plays a key role in the development of oral inflammation, such as periodontitis and gingivitis. In the last 10 years, F. nucleatum has been identified as a prevalent bacterium associated with colorectal adenocarcinoma and has also been linked to cancer progression, metastasis and poor disease outcome. While the role of F. nucleatum in colon carcinogenesis has been intensively studied, its role in gastric carcinogenesis is still poorly understood. Although Helicobacter pylori infection has historically been recognized as the strongest risk factor for the development of gastric cancer (GC), with recent advances in DNA sequencing technology, other members of the gastric microbial community, and F. nucleatum in particular, have received increasing attention. In this review, we summarize the existing knowledge on the involvement of F. nucleatum in gastric carcinogenesis and address the potential translational and clinical significance of F. nucleatum in GC.

Effectiveness of long-term low-dose aspirin in the prevention of gastric cancer after Helicobacter pylori eradication: study design and rationale of Ardabil gastric cancer randomized placebo-controlled prevention trial (AGCPT)

BackgroundIn addition to Helicobacter pylori (H. pylori) infection eradication, some medications, including aspirin, metformin, and statins, have been suggested to have protective effects against gastric cancer (GC) development in observational studies. We launched the Ardabil gastric cancer randomized placebo-controlled prevention trial (AGCPT) to evaluate the effectiveness of long-term low-dose aspirin use for the prevention of development and mortality of GC after H. pylori eradication.Methods/designAGCPT is a prospective population-based double-blind, randomized clinical trial. The study sample was targeted at 21,000 participants aged from 35 to 70 years old, both sexes, in Ardabil, a province in northwest Iran with relatively high rates of GC incidence and mortality. All eligible participants were initially tested for H. pylori infection using a H. pylori stool antigen test. Participants with positive tests undergo H. pylori eradication by standard treatment regimens. All participants with a negative test and those with a positive test with a subsequent confirmed H. pylori eradication test were entered into the intervention phase. In the intervention phase, participants were allocated randomly into either the treatment (daily oral consumption of 81 mg enteric-coated aspirin tablets) arm or the control (placebo) arm using permuted balanced blocks. Subjects will be followed for an average period of 10 years to evaluate the incidence and mortality rates of GC.DiscussionIn addition to preventing other diseases like cardiovascular events, aspirin may prevent GC incidence and mortality. AGCPT will investigate the difference between the two study arms in the proportion of the cumulative incidence and mortality rates of GC. The study’s results may help policymakers and researchers update the strategies for GC prevention.Trial registrationThis trial with the registry name of “The effect of Low-dose Aspirin in the Prevention of Gastric Cancer” was registered in the Iranian Registry of Clinical Trials, IRCT.ir, under the identifier IRCT201105082032N3. Registered on April 21, 2017.

Helicobacter pylori CagA mediated mitophagy to attenuate the NLRP3 inflammasome activation and enhance the survival of infected cells

Helicobacter pylori (H. pylori) is one of the most common bacterial infections in the world, and its key virulence component CagA is the leading cause of gastric cancer. Mitophagy is a form of selective autophagy that eliminates damaged mitochondria and is essential for some viruses and bacteria to evade the immune system. However, the mechanisms by which CagA mediates H. pylori-induced mitophagy and NLRP3 inflammasome activation remain elusive. In this study, we reported that H. pylori primarily uses its CagA to induce mitochondrial oxidative damage, mitochondrial dysfunction, dynamic imbalance, and to block autophagic flux. Inhibition of mitophagy led to an increase in NLRP3 inflammasome activation and apoptosis and a decrease in the viability of H. pylori-infected cells. Our findings suggested that H. pylori induces mitochondrial dysfunction and mitophagy primarily via CagA. It reduces NLRP3 inflammasome activation to evade host immune surveillance and increases the survival and viability of infected cells, potentially leading to gastric cancer initiation and development. Our findings provide new insights into the pathogenesis of H. pylori-induced gastric cancer, and inhibition of mitophagy may be one of the novel techniques for the prevention and treatment of this disease.

Prevention of Gastric Cancer: Helicobacter pylori Treatment

<i>Helicobacter pylori</i> infection has been associated with various gastric diseases, including ulcers, adenomas, and adenocarcinomas. Over 40 years since the discovery of <i>H. pylori</i>, numerous studies have shown that <i>H. pylori</i> eradication therapy can help prevent gastric cancer not only in healthy individuals but also in patients who have already been treated for early gastric cancer. Moreover, some studies have shown that eradication therapy can improve gastric mucosal inflammatory diseases, such as atrophic changes and intestinal metaplasia. This article reviews the epidemiology of <i>H. pylori</i> infections and gastric cancer, mechanisms of <i>H. pylori</i>-associated gastric cancer development, and current evidence supporting the benefits of <i>H. pylori</i> eradication for reducing or preventing gastric cancer.

Endoscopic screening for identification of signet ring cell gastric cancer foci in carriers of germline pathogenic variants in CDH1.

To determine the preoperative detection of signet ring cancer cells (SRC) on upper endoscopy (EGD) in patients with CDH1 pathogenic variant (PV) undergoing gastrectomy. To evaluate the development of advanced diffuse gastric cancer (DGC) in patients choosing surveillance. Guidelines recommend prophylactic total gastrectomy (pTG) in CDH1 PV carriers with family history of DGC between 18 and 40 years. Annual EGD with biopsies according to established protocols is recommended in carriers with no SRC and no family history of DGC, with consideration of pTG. Retrospective analysis of asymptomatic patients with CDH1 PVs with ≥ 1 surveillance EGD. Outcomes included pre-operative EGD detection of SRC, surgical stage, and progression to advanced DGC in those electing surveillance with EGD. 48 patients with CDH1 PVs who had ≥ 1 EGD were included. 24/ 48 (50%) underwent gastrectomy, including pTG in 7 patients. SRCC were detected on gastrectomy specimen in 21/24 (87.5%). SRCs were identified by EGD in 17/21 patients who had SRCC on gastrectomy specimens (sensitivity 81%, 17/21). All cancers were stage pT1a. The remaining 17 patients (50% with a family history of gastric cancer) continue in annual EGD surveillance with a median follow-up of 34.6 months. No SRCC or advanced DGC have been diagnosed. No CDH1 PV carriers without SRCC on random biopsies followed in an endoscopic program developed advanced DGC over a median follow up of 3 years. In the short term, EGD surveillance might be a safe alternative to immediate pTG in experienced hands in referral centers.

NFS1 inhibits ferroptosis in gastric cancer by regulating the STAT3 pathway.

Cysteine desulfurase (NFS1) is highly expressed in a variety of tumors, which is closely related to ferroptosis of tumor cells and affects prognosis. The relationship between NFS1 and the development of gastric cancer (GC) remains unknown. Here we showed that NFS1 expression was significantly higher in GC tissues compared to adjacent normal tissues. Patients with high expression of NFS1 in GC tissues had a lower overall survival rate than those with low expression. NFS1 was highly expressed in cultured GC cells compared to normal gastric cells. Knockdown of NFS1 expression reduced the viability, migration and invasion of GC cells. In cultured GC cells, NFS1 deficiency promoted ferroptosis. Mechanistically, NFS1 inhibited ferroptosis by upregulating the signal transduction and activator of transcription 3 (STAT3) signaling pathway in cultured GC cells. NFS1 knockdown using siRNA inhibited the STAT3 pathway, reduced the expression of glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11), and elevated intracellular levels of reactive oxygen species (ROS), ferrous ion (Fe2+), and malondialdehyde (MDA) in cultured GC cells. A specific STAT3 activator significantly reversed the inhibitory effect of NFS1 deficiency on ferroptosis in cultured GC cells. These in vitro results were further confirmed by experiments in vivo using a mouse xenograft tumor model. Collectively, THESE RESULTS INDICATE THAT NFS1 is overexpressed in human GC tissues and correlated with prognosis. NFS1 inhibits ferroptosis by activating the STAT3 pathway in GC cells. These results suggest that NFS1 may be a potential prognostic biomarker and therapeutic target to treat GC.

MiR-509-3p promotes gastric cancer development by activating FOXM1-mediated p38/MK2 pathway.

Gastric cancer (GC), a malignant tumor, is highly prevalent, particularly in Asia. miR-509-3p plays a crucial role in regulating tumorigenesis, but its mechanism in GC remains unclear. Potential targets of miR-509-3p were identified through database analysis (miRWalk, TargetScan, ENCORI, and TCGA). The binding site between miR-509-3p and forkhead box protein M1 (FOXM1) was confirmed using a dual-luciferase assay. CCK-8, EdU, Transwell, wound healing assays, flow cytometry, and Western blot analysis were employed to examine changes in proliferation, migration, invasion, apoptosis, FOXM1, and the p38 MAPK (p38)/MAPK-activated protein kinase 2 (MK2) pathway in GC cells (MNK-45 and HGC-27) after miR-509-3p overexpression or knockdown, FOXM1 overexpression, and application of the p38 pathway agonist Anisomycin. The size and weight of subcutaneous xenografts were measured, and the effects of miR-509-3p overexpression were analyzed through histopathological staining (Tunel immunofluorescence, HE staining, Ki67, and FOXM1 immunohistochemistry). The results showed that overexpression of miR-509-3p suppressed proliferation, migration, and invasion while accelerating apoptosis. Knockdown of miR-509-3p promoted malignant progression. miR-509-3p inhibited GC by regulating FOXM1-mediated p38/MK2 pathway activation, and miR-509-3p mimics restrained tumor growth in vivo through this pathway. In conclusion, miR-509-3p suppresses GC malignant progression by regulating FOXM1-mediated p38/MK2 pathway activation.

Integration of single-cell sequencing and bulk transcriptome data develops prognostic markers based on PCLAF+ stem-like tumor cells using artificial neural network in gastric cancer

BackgroundGastric cancer stem cells (GCSCs) are important tumour cells involved in tumourigenesis and gastric cancer development. However, their clinical value remains unclear due to the limitations of the available technologies. This study aims to explore the clinical significance of GCSCs, their connection to the tumour microenvironment, and their underlying molecular mechanisms. MethodsStem-like tumour cells were identified by mining single-cell transcriptomic data from multiple samples. Integrated analysis of single-cell and bulk transcriptome data was performed to analyse the role of stem-like tumour cells in predicting clinical outcomes by introducing the intermediate variable mRNA stemness degree (SD). Consensus clustering analysis was performed to develop an SD-related molecular classification strategy to assess the clinical characteristics in gastric cancer. A prognostic model was constructed using a customized approach that comprehensively considered SD-related gene signatures based on an artificial neural network. ResultsBy analysing single-cell data and validating immunofluorescence results, we identified a PCLAF+ stem-like tumour cell population in GC. By calculating SD, we observed that PCLAF+ stem-like tumour cells were associated with poor prognosis and certain clinical features. The SD was negatively correlated with the abundance of most immune cell types. Furthermore, we proposed an SD-related classification method and prognostic model. In addition, the customised prognostic model can be used to predict whether a patient respond to PD-1/PD-L1 immunotherapy. ConclusionWe identified a cluster of stem-like cells and elucidated their clinical significance, highlighting the possibility of their use as immunotherapeutic targets.

Eupafolin hinders cross-talk between gastric cancer cells and cancer-associated fibroblasts by abrogating the IL18/IL18RAP signaling axis

BackgroundCancer-associated fibroblasts (CAFs) are involved in the progression of gastric cancer (GC) as a critical component of the tumor microenvironment (TME), yet specific interventions remain limited. Natural products hold a promising application prospect in the field of anti-tumor in view of their high activity and ease of binding with biological macromolecules. However, the role of natural products in modulating the cross-talk between CAFs and GC cells has not been fully investigated. PurposeThe aim of this study was to identify a potential therapeutic target in CAFs and then screen for natural small molecule drugs with anti-tumor activity against this target. MethodsIntegrating bioinformatics analysis of public databases and experimental validation of human samples and cell lines to identify a candidate target in CAFs. Molecular docking and biolayer interferometry technique were utilized for screening potential natural small molecule drugs. The efficacy and underlying mechanisms of the candidates were explored in vitro and in vivo through techniques such as lentiviral infection, cell spheroids culture, immunoprecipitation and cells-derived xenografts. ResultsIL18 receptor accessory protein (IL18RAP) was found to be overexpressed in CAFs derived from GC tissues and facilitated the protumor function of CAFs on GC. Based on virtual screening and experimental validation, we identified a natural product, eupafolin, that interfered with IL18 signaling. Phenotyping studies confirmed that the proliferation, spheroids formation and tumorigenesis of GC cells facilitated by CAFs were greatly attenuated by eupafolin both in vitro and in vivo. Mechanistically, eupafolin impeded the formation of IL18 receptor (IL18R) complex by directly binding to IL18RAP, thus blocking IL18-mediated nuclear factor kappa B (NF-κB) activation and reduced the synthesis and secretion of IL6 in CAFs. As a consequence, it inactivated signal transducer and activator of transcription 3 (STAT3) in GC cells. ConclusionThis study provides new evidence that IL18 signaling regulates the cross-talk between GC cells and CAFs. And it highlights a novel pharmacological role of eupafolin in inhibiting IL18 signaling, thereby curbing the development of GC via modulating CAFs.

GGT5 as a promising prognostic biomarker and its effects on tumor cell progression in gastric cancer.

Gastric cancer (GC) is a gastric malignant tumor with over 1 million new cases globally each year. There are many diagnostic methods for GC, but due to the hidden early symptoms of GC, early GC is easy to be missed and misdiagnosed, which affects the follow-up treatment of patients. The early and accurate diagnosis of GC is of great significance for the treatment and survival of GC patients. Our laboratory study found that gamma-glutamyl transferase (GGT) was highly expressed in GC patients, but the mechanism of GGT family genes in the occurrence and development of GC remained to be further studied. Therefore, this study aimed to explore the mechanism of GGT family functional gene GGT5 regulating the proliferation and migration of GC cells, and provide a possible new biomarker for the early diagnosis of GC. The value of serum GGT in GC patients was first statistically analyzed. Then, The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets were used to analyze the mRNA expression of GGT5 in GC, and its clinical relationship and function. Furthermore, expression of GGT5 was reduced by lentivirus RNA interference and verified by polymerase chain reaction (PCR), Cell Counting Kit-8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EdU) assays were used to detect cell proliferation after GGT5 knockdown. Scratch and Transwell assays were applied to observe cell migration after knockdown of GGT5. Finally, Western blot assays were observed to demonstrate PI3K/AKT-MAPK and MMPs expression levels after knockdown of GGT5. Serum GGT was expressed at a high level in GC patients. GGT5 was highly expressed in GC tissues, and was associated with poor prognosis and clinical stage of GC. GGT5 might be involved in the regulation of vascular development and angiogenesis, as well as in the mechanisms of cell motility and migration, and it was positively correlated with the PI3K/AKT pathway. The proliferation and migration capacity of GC cells was dampened by downregulation of GGT5. GGT5 mediated proliferation and migration of GC cells by directly targeting PI3K/AKT-MAPK-MMPs pathways. Low expression of GGT5 reduced proliferation and migration in GC cells by modulating the PI3K/AKT-MAPK-MMPs pathway, and GGT5 might be a new target for GC.

Protein Biomarkers of Gastric Preneoplasia and Cancer Lesions in Blood: A Comprehensive Review.

Gastric cancer (GC) is a major cause of cancer-related mortality worldwide. It is often associated with a bad prognosis because of its asymptomatic phenotype until advanced stages, highlighting the need for its prevention and early detection. GC development is preceded by the emergence of gastric preneoplasia lesions (GPNLs), namely atrophic gastritis (AG), intestinal metaplasia (IM), and dysplasia (DYS). GC is currently diagnosed by endoscopy, which is invasive and costly and has limited effectiveness for the detection of GPNLs. Therefore, the discovery of non-invasive biomarkers in liquid biopsies, such as blood samples, in order to identify the presence of gastric preneoplasia and/or cancer lesions at asymptomatic stages is of paramount interest. This comprehensive review provides an overview of recently identified plasma/serum proteins and their diagnostic performance for the prediction of GPNLs and early cancer lesions. Autoantibodies appear to be promising biomarkers for AG, IM and early gastric cancer detection, along with inflammation and immunity-related proteins and antibodies against H. pylori virulence factors. There is a lack of specific protein biomarkers with which to detect DYS. Despite the need for further investigation and validation, some emerging candidates could pave the way for the development of reliable, non-invasive diagnostic tests for the detection and prevention of GC.

Autoimmune gastritis studies and gastric cancer: True renaissance or bibliometric illusion.

A bibliometric analysis of studies dedicated to autoimmune gastritis (AIG) recently published demonstrated a noteworthy surge in publications over the last three years. This can be explained by numerous publications from different regions of the world reporting the results of several studies that stimulated reassessment of our view of AIG as a precancerous condition. Follow-up studies and retrospective analyses showed that the risk of gastric cancer (GC) in AIG patients is much lower than expected if the patients ever being infected with Helicobacter pylori (H. pylori) were excluded. The low prevalence of precancerous lesions, such as the incomplete type of intestinal metaplasia, may explain the low risk of GC in AIG patients because the spasmolytic polypeptide-expressing metaplasia commonly observed in AIG does not involve clonal reprogramming of the gastric gland and can be considered as an adaptive change rather than a true precancerous lesion. However, changes in gastric secretion due to the progression of gastric atrophy during the course of AIG cause changes in the gastric mic-robiome, stimulating the growth of bacterial species such as streptococci, which may promote the development of precancerous lesions and GC. Thus, Streptococcus anginosus exhibited a robust proinflammatory response and induced the gastritis-atrophy-metaplasia-dysplasia sequence in mice, reproducing the well-established process for carcinogenesis associated with H. pylori. Prospective studies in H. pylori-naïve patients evaluating gastric microbiome changes during the long-term course of AIG might provide an explanation for the enigmatic increase in GC incidence in the last decades in younger cohorts, which has been reported in economically developed countries.

Thirdhand smoke exposure promotes gastric tumor development in mouse and human

The pollution of indoor environments and the consequent health risks associated with thirdhand smoke (THS) are increasingly recognized in recent years. However, the carcinogenic potential of THS and its underlying mechanisms have yet to be thoroughly explored. In this study, we examined the effects of short-term THS exposure on the development of gastric cancer (GC) in vitro and in vivo. In a mouse model of spontaneous GC, CC036, we observed a significant increase in gastric tumor incidence and a decrease in tumor-free survival upon THS exposure as compared to control. RNA sequencing of primary gastric epithelial cells derived from CC036 mice showed that THS exposure increased expression of genes related to the extracellular matrix and cytoskeletal protein structure. We then identified a THS exposure-induced 91-gene expression signature in CC036 and a homologous 84-gene signature in human GC patients that predicted the prognosis, with secreted phosphoprotein 1 (SPP1) and tribbles pseudokinase 3 (TRIB3) emerging as potential targets through which THS may promote gastric carcinogenesis. We also treated human GC cell lines in vitro with media containing various concentrations of THS, which, in some exposure dose range, significantly increased their proliferation, invasion, and migration. We showed that THS exposure could activate the epithelial-mesenchymal transition (EMT) pathway at the transcript and protein level. We conclude that short-term exposure to THS is associated with an increased risk of GC and that activation of the EMT program could be one potential mechanism. Increased understanding of the cancer risk associated with THS exposure will help identify new preventive and therapeutic strategies for tobacco-related disease as well as provide scientific evidence and rationale for policy decisions related to THS pollution control to protect vulnerable subpopulations such as children.