Gastric Cancer Etiology and Management in Asia and the West

Surgical Techniques and Related Perioperative Outcomes After Robot-assisted Minimally Invasive Gastrectomy (RAMIG): Results From the Prospective Multicenter International Ugira Gastric Registry

OBJECTIVE

To gain insight into the global practice of robot-assisted minimally invasive gastrectomy (RAMIG) and evaluate perioperative outcomes using an international registry.

BACKGROUND

The techniques and perioperative outcomes of RAMIG for gastric cancer vary substantially in the literature.

METHODS

Prospectively registered RAMIG cases for gastric cancer (≥10 per center) were extracted from 25 centers in Europe, Asia, and South-America. Techniques for resection, reconstruction, anastomosis, and lymphadenectomy were analyzed and related to perioperative surgical and oncological outcomes. Complications were uniformly defined by the Gastrectomy Complications Consensus Group.

RESULTS

Between 2020 and 2023, 759 patients underwent total (n=272), distal (n=465), or proximal (n=22) gastrectomy (RAMIG). After total gastrectomy with Roux-en-Y-reconstruction, anastomotic leakage rates were 8% with hand-sewn (n=9/111) and 6% with linear stapled anastomoses (n=6/100). After distal gastrectomy with Roux-en-Y (67%) or Billroth-II-reconstruction (31%), anastomotic leakage rates were 3% with linear stapled (n=11/433) and 0% with hand-sewn anastomoses (n=0/26). Extent of lymphadenectomy consisted of D1+ (28%), D2 (59%), or D2+ (12%). Median nodal harvest yielded 31 nodes (interquartile range: 21-47) after total and 34 nodes (interquartile range: 24-47) after distal gastrectomy. R0 resection rates were 93% after total and 96% distal gastrectomy. The hospital stay was 9 days after total and distal gastrectomy, and was median 3 days shorter without perianastomotic drains versus routine drain placement. Postoperative 30-day mortality was 1%.

CONCLUSIONS

This large multicenter study provided a worldwide overview of current RAMIG techniques and their respective perioperative outcomes. These outcomes demonstrated high surgical quality, set a quality standard for RAMIG, and can be considered an international reference for surgical standardization.

Staging laparoscopy in gastric cancer patients: From a Dutch nationwide Delphi consensus towards a standardized protocol

BACKGROUND

Staging laparoscopy is a common diagnostic tool in gastric cancer, but its performance varies widely. The aim of this study was to gain Dutch nationwide consensus regarding the indications for and execution of staging laparoscopy in patients with gastric cancer.

METHODS

All surgeons in the Netherlands specialized in gastric cancer surgery (n = 52) were asked to participate in a Delphi consensus study. The study involved an initial questionnaire with a 3-point Likert scale, an online consensus meeting, and a second questionnaire using a 2-point Likert scale (agree/disagree). Consensus was defined as 70% or more agreement among participants.

RESULTS

In total, 45 experts completed both questionnaires (87% response rate). Consensus was reached on the indication to perform staging laparoscopy in cT3-4 or cN + or diffuse-type gastric cancer, including Siewert type III oesophagogastric junctional cancer. The experts agreed that if preoperative scans suggest infiltration of surrounding organs (cT4), the tumour's resectability should explicitly be investigated. Consensus was also reached for a systematic peritoneal cavity inspection according to Sugarbaker's Peritoneal Cancer Index (PCI) score. All regions should be inspected routinely, although the omental bursa may be inspected on indication. Aspiration of ascites or peritoneal washing should be performed for cytology. The experts agreed that restaging laparoscopy should be performed before resection in case of progressive disease on preoperative imaging. Without progression, global inspection was considered sufficient.

CONCLUSIONS

The results of this Dutch nationwide Delphi consensus study exposed the variability of performing staging laparoscopy in patients with gastric cancer and provided the concept for a standardized protocol.

Global, regional, and national cancer burdens of respiratory and digestive tracts in 1990-2044: A cross-sectional and age-period-cohort forecast study

BACKGROUND

Understanding the current status and future trends of cancer burdens by systems provides important information for specialists, policymakers, and specific risk populations.

METHODS

The aim of this study was to compare the current and future cancer burdens of the gastrointestinal (GI) and respiratory tracts in terms of their magnitude and distribution. Data from a total of eight cancers of the digestive and respiratory tracts in the Global Burden of Disease (GBD) database were collected. The age-standardized incidence/death rates (ASIR/ASDRs), disability-adjusted life years (DALYs), and estimated annual percentage changes (EAPCs) were analyzed. Future trends were predicted with Bayesian age-period-cohort (BAPC) and NORDPRED models.

RESULTS

In 2019, there was a significant increase in DALY for both digestive and respiratory tract cancers compared to 1990. Meanwhile, ASIR increased slightly and ASDR decreased notably. In 2019, the global cancer burdens of respiratory and digestive tracts were 38568363.53 and 66912328.72 in DALY, 34.28 and 55.32 in ASIR, and 656.82 and 808.22 in ASDR per 100,000 population with changes of +54.63% and +43.93%, +2.92% and +5.65%, and -17.39% and -26.83% compared to those in 1990, respectively. Significant cross-regional differences in the cancer burdens were observed among the regions. Compared to four representative chronic diseases, the burden of cancers showed less remission and greater global inequalities. The burdens of both digestive and respiratory tract cancers were higher in males than in females in terms of the ASIR, ASDR, and DALY. The incidence and mortality rates of respiratory tract cancers were up to 3-4 times higher in males than in females, whereas the difference between male and female rates of digestive tract cancers was relatively smaller. The main risk factor associated with all kinds of digestive and respiratory tract cancers is tobacco, leading to 18.5 in ASDR and 3.38×107 in DALY for respiratory tract cancers; 8.29 in ASDR and 1.60×107 in DALY for digestive tract cancers, in 2019. Additionally, alcohol use contributes to most digestive and respiratory tract cancers (1.23/1.03 in ASDR and 1.60×106/2.57×106 in DALY for respiratory tract cancers; 4.19/3.82 in ASDR and 4.49×106/8.06×106 in DALY for digestive tract cancers), except for stomach cancer and tracheal, bronchus, and lung cancer. The cancer burdens of respiratory and digestive tracts are likely to decrease substantially between 2020 and 2044. For most metrics, except for the ASIR and male-to-female ratios of ASDR and ASDALY in digestive tract cancers, the worldwide variances of burden metrics have been decreasing in the past decades and will possibly maintain stable trends in the future.

CONCLUSIONS

The epidemiology of respiratory and GI tract cancers has common features and individual characteristics that are reflected in geography, age characteristics, and risk factors. Current epidemiological status, future trends, and the globalization of these disease burdens are important factors for making scientific planning of resources to minimize the cancer burden metrics and their cross-regional inequalities.

Comparison of the Prognosis of Upper-Third Gastric Cancer With That of Middle and Lower-Third Gastric Cancer

PURPOSE

Gastric cancer is one of the most common cancers in Korea, and the proportion of upper-third gastric cancers has been steadily increasing over the last two decades. This study aimed to evaluate the effect of tumor location on gastric cancer prognosis.

MATERIALS AND METHODS

We retrospectively reviewed 2,466 patients who underwent gastrectomy for pathologically proven gastric cancer between January 2011 and December 2016. The patients were divided into an upper-third group (U group; n=419, 17.0%) and a middle- and lower-third group (ML group; n=2,047, 83.0%). Clinicopathological characteristics, overall survival (OS), and recurrence-free survival (RFS) after surgery were compared.

RESULTS

The U group had more advanced disease than the ML group and a higher incidence of N3b disease for T3 (12.0% vs. 4.9%, p=0.023) and T4 tumors (33.3% vs. 17.5%, p=0.001). The 5-year RFS rate for stage III disease was marginally lower in the U group than that in the ML group (47.1% vs. 56.7%, p=0.082). The upper third location was an independent prognostic factor for both OS (hazard ratio [HR], 1.350; 95% confidence interval [CI], 1.065-1.711) and RFS (HR, 1.430; 95% CI, 1.080-1.823).

CONCLUSIONS

Upper-third gastric cancer shows extensive node metastasis compared to those located more distally in ≥T3 tumors. The upper third location is an independent prognostic factor for both OS and RFS and may have an adverse impact on RFS, particularly in patients with stage III gastric cancer.

Liquid biopsy for gastric cancer: Techniques, applications, and future directions

After the study of circulating tumor cells in blood through liquid biopsy (LB), this technique has evolved to encompass the analysis of multiple materials originating from the tumor, such as nucleic acids, extracellular vesicles, tumor-educated platelets, and other metabolites. Additionally, research has extended to include the examination of samples other than blood or plasma, such as saliva, gastric juice, urine, or stool. LB techniques are diverse, intricate, and variable. They must be highly sensitive, and pre-analytical, patient, and tumor-related factors significantly influence the detection threshold, diagnostic method selection, and potential results. Consequently, the implementation of LB in clinical practice still faces several challenges. The potential applications of LB range from early cancer detection to guiding targeted therapy or immunotherapy in both early and advanced cancer cases, monitoring treatment response, early identification of relapses, or assessing patient risk. On the other hand, gastric cancer (GC) is a disease often diagnosed at advanced stages. Despite recent advances in molecular understanding, the currently available treatment options have not substantially improved the prognosis for many of these patients. The application of LB in GC could be highly valuable as a non-invasive method for early diagnosis and for enhancing the management and outcomes of these patients. In this comprehensive review, from a pathologist's perspective, we provide an overview of the main options available in LB, delve into the fundamental principles of the most studied techniques, explore the potential utility of LB application in the context of GC, and address the obstacles that need to be overcome in the future to make this innovative technique a game-changer in cancer diagnosis and treatment within clinical practice.

Allyl isothiocyanate induces DNA damage and inhibits DNA repair-associated proteins in a human gastric cancer cells in vitro

Allyl isothiocyanate (AITC) is abundant in cruciferous vegetables and it present pharmacological activity including anticancer activity in many types of human cancer cells in vitro and in vivo. Currently, no available information to show AITC affecting DNA damage and repair-associated protein expression in human gastric cancer cells. Therefore, in the present studies, we investigated AITC-induced cytotoxic effects on human gastric cancer in AGS and SNU-1 cells whether or not via the induction of DNA damage and affected DNA damage and repair associated poteins expressions in vitro. Cell viability and morphological changes were assayed by flow cytometer and phase contrast microscopy, respectively, the results indicated AITC induced cell morphological changes and decreased total viable cells in AGS and SNU-1 cells in a dose-dependently. AITC induced DNA condensation and damage in a dose-dependently which based on the cell nuclei was stained by 4', 6-diamidino-2-phenylindole present in AGS and SNU-1 cells. DNA damage and repair associated proteins expression in AGS and SNU-1 cells were measured by Western blotting. The results indicated AITC decreased nuclear factor erythroid 2-related factor 2 (NRF2), heme oxygenase-1 (HO-1), glutathione, and catalase, but increased superoxide dismutase (SOD (Cu/Zn)), and nitric oxide synthase (iNOS) in AGS cells, however, in SNU-1 cells are increased HO-1. AITC increased DNA-dependent protein kinase (DNA-PK), phosphorylation of gamma H2A histone family member X on Ser139 (γH2AXpSer139 ), and heat shock protein 90 (HSP90) in AGS cells. AITC increased DNA-PK, mediator of DNA damage checkpoint protein 1 (MDC1), γH2AXpSer139 , topoisomerase II alpha (TOPIIα), topoisomerase II beta (TOPIIβ), HSP90, and heat shock protein 70 (HSP70) in SNU-1 cells. AITC increased p53, p53pSer15 , and p21 but decreased murine double minute 2 (MDM2)pSer166 and O6 -methylguanine-DNA methyltransferase (MGMT) in AGS cells; however, it has a similar effect of AITC except increased ataxia telangiectasia and Rad3 -related protein (ATR)pSer428 , checkpoint kinase 1 (CHK1), and checkpoint kinase 2 (CHK2) in SNU-1 cells. Apparently, both cell responses to AITC are different, nonetheless, all of these observations suggest that AITC inhibits the growth of gastric cancer cells may through induction off DNA damage in vitro.

Mutational landscape of TP53 and CDH1 in gastric cancer

In this editorial we comment on an article published in a recent issue of the World J Gastrointest Surg. A common gene mutation in gastric cancer (GC) is the TP53 mutation. As a tumor suppressor gene, TP53 is implicated in more than half of all tumor occurrences. TP53 gene mutations in GC tissue may be related with clinical pathological aspects. The TP53 mutation arose late in the progression of GC and aided in the final switch to malignancy. CDH1 encodes E-cadherin, which is involved in cell-to-cell adhesion, epithelial structure maintenance, cell polarity, differentiation, and intracellular signaling pathway modulation. CDH1 mutations and functional loss can result in diffuse GC, and CDH1 mutations can serve as independent prognostic indicators for poor prognosis. GC patients can benefit from genetic counseling and testing for CDH1 mutations. Demethylation therapy may assist to postpone the onset and progression of GC. The investigation of TP53 and CDH1 gene mutations in GC allows for the investigation of the relationship between these two gene mutations, as well as providing some basis for evaluating the prognosis of GC patients.

Molecular Classifications in Gastric Cancer: A Call for Interdisciplinary Collaboration

Gastric cancer (GC) is a heterogeneous disease, often diagnosed at advanced stages, with a 5-year survival rate of approximately 20%. Despite notable technological advancements in cancer research over the past decades, their impact on GC management and outcomes has been limited. Numerous molecular alterations have been identified in GC, leading to various molecular classifications, such as those developed by The Cancer Genome Atlas (TCGA) and the Asian Cancer Research Group (ACRG). Other authors have proposed alternative perspectives, including immune, proteomic, or epigenetic-based classifications. However, molecular stratification has not yet transitioned into clinical practice for GC, and little attention has been paid to alternative molecular classifications. In this review, we explore diverse molecular classifications in GC from a practical point of view, emphasizing their relationships with clinicopathological factors, prognosis, and therapeutic approaches. We have focused on classifications beyond those of TCGA and the ACRG, which have been less extensively reviewed previously. Additionally, we discuss the challenges that must be overcome to ensure their impact on patient treatment and prognosis. This review aims to serve as a practical framework to understand the molecular landscape of GC, facilitate the development of consensus molecular categories, and guide the design of innovative molecular studies in the field.

Population-based X-ray gastric cancer screening in Hiroshima prefecture, Japan

BACKGROUND

X-ray gastric cancer (GC) screening has been shown to decrease mortality. Population-based X-ray GC screening has been performed in Hiroshima Prefecture, Japan, since 1983 but time trends and the efficacy of the method over 39 years have not been assessed.

AIM

To evaluate time trends and efficacy of population-based X-ray GC screening and identify challenges and suggested solutions for the future.

METHODS

This was a population-based retrospective study. The data were derived from aggregated data of the Hiroshima Regional Health Medical Promotion Organization, including the number and rate of participants and those requiring esophagogastroduodenoscopies (EGDs), the number and rate of participants diagnosed as having GC, and the positive predictive value of the abnormal findings detected by X-ray and confirmed by EGDs. The number and rate of esophageal cancers were also collected. Further, the cost of detecting one GC was evaluated.

RESULTS

The number of participants has decreased during the last four decades, from 39925 in 1983 to 12923 in 2021. The rate of those requiring EGDs decreased significantly in recent years (P < 0.001). The number of participants diagnosed as having GC has also declined, from 76 to 10 cases. However, the rate of cases diagnosed as GC among the participants remained around 0.1%. The positive predictive value increased significantly in recent years except during 1983-1991. The number and rate of accidentally detected esophageal cancers have risen recently, from 0% in 2008 to 0.02% in 2021, one-fifth of the diagnosis rate of GC. One GC diagnosis costs approximately 4200000 Japanese Yen (30000 United States Dollars) for the X-ray screenings and EGDs.

CONCLUSION

X-ray GC screening in Hiroshima has been efficient, but one challenge is the cost. Esophageal cancers may also need to be considered because they have gradually increased in recent years.

Immune checkpoint inhibitors or anti-claudin 18.2 antibodies? A network meta-analysis for the optimized first-line therapy of HER2-negative gastric cancer

Background

Multiple anti-programmed cell death-1/programmed cell death-ligand 1 (PD-1/PD-L1) inhibitors and zolbetuximab, an anti-claudin 18.2 antibody, have shown efficacy in the first-line treatment of HER2-negative gastric cancers. How to choose the best regimen remains an unsolved question.

Objectives

We aimed to conduct a comparative analysis of the therapeutic advantages between immunotherapy and anti-claudin-18.2-targeted therapies in the first-line treatment of HER2-negative, unresectable, or metastatic gastric cancers.

Design

Network meta-analysis was employed to systematically compare efficacy and safety data derived from various clinical trials.

Data sources and methods

We included phase III randomized controlled trials in PubMed, Embase, Web of Science, Cochrane Library, and major conference abstracts. Network meta-analysis was used to compare the efficacy of each first-line therapeutic agent and to indirectly compare immunotherapy with anti-claudin-18.2-targeted therapy.

Results

Eight trials comprising a total of 6455 patients were included. For the overall survival (OS) analysis, no statistically significant differences were observed between pembrolizumab [hazard ratios (HR) = 1.00, 95% CI: 0.94-1.07], sintilimab (HR = 0.99, 95% CI: 0.89-1.09), sugemalimab (HR = 0.98, 95% CI: 0.87-1.10), tislelizumab (HR = 0.97, 95% CI: 0.87-1.09), zolbetuximab (HR = 0.98, 95% CI: 0.91-1.07), and nivolumab (HR = 1.00). For the progression-free survival (PFS) analysis, no statistically significant differences were observed between pembrolizumab (HR = 1.00, 95% CI: 0.93-1.06), sintilimab (HR = 0.91, 95% CI: 0.83-1.00), sugemalimab (HR = 0.92, 95% CI: 0.84-1.02), tislelizumab (HR = 0.93, 95% CI: 0.84-1.03), zolbetuximab (HR = 0.96, 95% CI: 0.88-1.05), and nivolumab (HR = 1.00). For the overall response rate analysis, all regimens presented similar effects on ORR. In addition, anti-claudin-18.2-targeted therapies presented similar OS (HR = 0.99, 95% CI: 0.95-1.04) and PFS (HR = 1.01, 95% CI: 0.91-1.12) compared to immunotherapy, although their toxicity profiles were distinct.

Conclusions

Our network meta-analysis showed no significant difference in PFS, OS, or ORR between different checkpoint inhibitors or between immunotherapy and anti-claudin-18.2-targeted therapies in the first-line treatment of HER2-negative, unresectable, or metastatic gastric cancers.

Advances in RNAi therapies for gastric cancer: Targeting drug resistance and nanoscale delivery

Gastric cancer poses a significant health challenge, and exploring innovative therapeutic strategies is imperative. RNA interference (RNAi) has employed as an important therapeutic strategy for diseases by selectively targeting key pathways involved in diseases pathogenesis. Small interfering RNA (siRNA), a potent RNAi tool, possesses the capability to silence genes and downregulate their expression. This review provides a comprehensive examination of the potential applications of small interfering RNA (siRNA) and short hairpin RNA (shRNA), supplemented by an in-depth analysis of nanoscale delivery systems, in the context of gastric cancer treatment. The potential of siRNA to markedly diminish the proliferation and invasion of gastric cancer cells through the modulation of critical molecular pathways, including PI3K, Akt, and EMT, is highlighted. Besides, siRNA demonstrates its efficacy in inducing chemosensitivity in gastric tumor cells, thus impeding tumor progression. However, the translational potential of unmodified siRNA faces challenges, particularly in vivo and during clinical trials. To address this, we underscore the pivotal role of nanostructures in facilitating the delivery of siRNA to gastric cancer cells, effectively suppressing their progression and enhancing gene silencing efficiency. These siRNA-loaded nanoparticles exhibit robust internalization into gastric cancer cells, showcasing their potential to significantly reduce tumor progression. The translation of these findings into clinical trials holds promise for advancing the treatment of gastric cancer patients.

Prognostic role of the number of resected and negative lymph nodes in Spanish patients with gastric cancer

INTRODUCTION

Lymph node (LN) involvement is one of the most critical prognostic factors in resected gastric cancer (GC). Some analyses, mainly conducted in Asian populations, have found that patients with a higher number of total lymph nodes (NTLN) and/or negative lymph nodes (NNLN) have a better prognosis, although other authors have failed to confirm these results.

MATERIALS AND METHODS

Retrospective study including all patients with GC resected in a tertiary hospital in Spain between 2001 and 2019 (n = 315). Clinicopathological features were collected and patients were categorized according to the NTLN and the NNLN. Statistical analyses were performed.

RESULTS

Mean NNLN was 17. The NNLN was significantly related to multiple clinicopathological variables, including recurrence and tumor-related death. The classification based on the NNLN (N1: ≥16, N2: 8-15, N3: ≤7) effectively stratified the entire cohort into three distinct prognostic groups and maintained its prognostic value within both the pN0 and pN+ patient subsets. Furthermore, it was an independent prognostic indicator for both overall and disease-free survival. Conversely, the mean NTLN was 21.9. Patients with ≤16 LN retrieved exhibited distinct clinicopathological features compared to those with >16 LN, but no significant differences were observed in terms of recurrence or disease-associated death. The application of alternative cut-off points for NTLN (10, 20, 25, 30, and 40) showed no prognostic significance.

CONCLUSIONS

In Spanish patients with resected GC the NNLN hold prognostic significance, while the NTLN does not appear to be prognostically significant. Incorporating the NNLN into GC staging may enhance the accuracy of the TNM system.

Expression of selected long non-coding RNAs in gastric cancer cells treated with coumarin: Possible mechanisms for anti-cancer activity

Long non-coding RNAs (lncRNAs) can be utilized as prognostic indicators of gastric cancer since they can affect several cancer-related processes. Coumarin is a natural product with some useful anti-cancer properties. Here, we measured the expression of selected lncRNAs (RuPAR, SNHG6, CASC11, and their targets, miR-340-5p, p21, E-cadherin, and CDK1) in AGS gastric cancer cells treated with coumarin. MTT test has been utilized for assessing the AGS cells' cell viability after exposure to coumarin. The expression of the lncRNAs (RuPAR, SNHG6, and CASC11) and miR-340-5p was evaluated via qRT-PCR. Western blot analysis has been utilized to determine changes in p21, E-cadherin, and CDK1 expression. Coumarin decreased AGS viability in a dose-dependent manner. The coumarin treated cells had lower levels of the mRNAs known to be targets of lncRNAs SNHG6 and CASC11 compared to control. Additionally, the coumarin group had increased levels of lncRNA RuPAR expression when compared with the control group. Some lncRNA targets, including p21, E-cadherin, and CDK1, showed lower expression in the coumarin group compared to the control by Western blotting. Coumarin could be a promising pharmacological candidate to be included in gastric cancer treatment regimens because it modulates lncRNAs and their targets.

System biology analysis to develop diagnostic biomarkers, monitoring pathological indexes, and novel therapeutic approaches for immune targeting based on maggot bioactive compounds and polyphenolic cocktails in mice with gastric cancer

Early diagnosis and prognosis are prerequisites for mitigating mortality in gastric cancer (GaCa). Identifying some causative or sensitive elements (coding RNA (cRNA)-non-cRNAs (ncRNAs)) can be very helpful in the early diagnosis of GaCa. Notably, despite significant development in the GaCa treatment, the outcome of patients does not remain satisfactory due to limitations such as multi-drug resistance and tumor relapse. Therefore, more attention has been drawn to complementary therapies and the use of supplements. In this regard, Polyphenol natural compounds (PNC) and maggot larvae (MaLa) alone or in combination were administered along with chemotherapy (paclitaxel) to N-methyl-N-nitrosourea (MNU)- induced murine tumor model. In addition, in order to identify potential diagnostic or prognostic biomarkers, transcriptomics analysis was performed through a bioinformatics approach. Then transcription profile of ncRNAs with their target hub genes was assessed through qPCR Real-Time, Western blot, and ELISA. According to the bioinformatics results, 17 hub genes (e.g., IL-6, CXCL8, MKI67, IL-2, IL-4, IL-10, IL-1β, SPP1, LOX, COL1A1, and IFN-γ) were explored that contribute towards inflammation and oxidative stress and ultimately GaCa development. Upstream of the mentioned hub genes, regulatory factors (lncRNA XIST and NEAT1) were also identified and introduced as prognosis and diagnosis biomarkers for GaCa. Our results showed that PNC alone and in combination with MaLa was able to reduce the size and number of tumors, which is related to the reduction of genes expression levels (including IL-6, CXCL8, MKI67, IL-2, IL-4, IL-10, IL-1β, SPP1, LOX, COL1A1, IFN-γ, NEAT1, and XIST). In conclusion, PNC and MaLa have the potential to be considered as complementary and improving chemotherapy due to their effective compounds. Also, the introduced hub gene and lncRNA in addition to diagnostic and prognostic biomarkers can be used as druggable proteins for novel therapeutic targeting of GaCa.

An immunogenic cell death-related signature predicts prognosis and immunotherapy response in stomach adenocarcinoma

The immunogenic cell death (ICD) is a specific type of regulatory cell death (RCD), which induces adaptive immunity against antigens of dead cells. ICDs have received increasing attention for their potential role in tumor microenvironment reprogramming and immunotherapy. However, the relationship between ICD-related features and stomach adenocarcinoma (STAD) prognosis, immune cell infiltration and immunotherapy remains unclear. Patients were divided into different ICD-related subtypes by consensus clustering. The differences in prognosis, Tumor microenvironment (TME), and immune checkpoint expression between different ICD-related subtypes were systematically assessed. Additionally, we constructed an ICD-related gene risk score (ICDRS). We systematically analyzed the correlation between ICDRS and prognosis, TME, immunotherapy response and drug sensitivity of gastric cancer. In addition, we explored the role of TGM2 in promoting gastric cancer progression through in vitro experiments. We identified three ICD-associated subtypes by consensus clustering. The ICD gene was highly expressed in Cluster B. Compared with the other two subtypes, Cluster B had better prognosis, higher immune response signaling activity, massive immune cell infiltration and lower tumor purity. Immune checkpoint (ICP) and human leukocyte antigen (HLA) related genes were also highly expressed in Cluster B. In addition, we found that ICDRS is an effective indicator for predicting the prognosis and immune efficacy of STAD. The low ICDRS group has the characteristics of good prognosis, high tumor mutation burden (TMB), high microsatellite instability (MSI), and sensitivity to immunotherapy, while the high ICDRS group is prone to immune escape and immunotherapy resistance. In addition, we found that down-regulating TGM2 gene can inhibit the proliferation and migration of gastric cancer cells through in vitro experiments. Our study found that the model based on ICD features is helpful to clarify the TME characteristics of STAD, and has important clinical significance for evaluating the prognosis and immunotherapy response of STAD patients. TGM2 plays an important role in the progression of STAD, suggesting that TGM2 can be used as a new target for the treatment of STAD.

The influence of partial gastrectomy for gastric cancer on the spontaneous disappearance of Helicobacter pylori: A single-center prospective study

BACKGROUND/AIMS

Helicobacter pylori (HP) eradication is recommended after endoscopic treatment of early gastric cancer (EGC). Cases of spontaneous HP resolution after partial gastrectomy due to environmental changes have been reported; however, there is no evidence for the efficacy of HP eradication in suppressing carcinogenesis and also no reports on the natural history of HP after partial gastrectomy in gastric cancer (GC). To report the natural history of HP in patients with GC and HP infection after partial gastrectomy.

METHODS AND RESULTS

We prospectively studied the rate of spontaneous disappearance of HP after partial gastrectomy in patients with GC. From April 2016 to May 2020, 80 patients underwent partial gastrectomy, including 9 cases of proximal gastrectomy (PG), and 71 cases of distal gastrectomy (DG). The presence of HP was confirmed in the stool antigen test 1 year after operation, HP infection persisted in 46 patients (57.5%) and disappeared in 34 patients (42.5%). In univariate analysis, only proton pump inhibitor (PPI) use was a significant contributing factor for the spontaneous resolution of HP infection, especially in the DG group. However, there was no difference in the rates of HP disappearance between Billroth-I and Roux-en-Y reconstructions in the DG group.

CONCLUSION

The HP spontaneously disappeared in 42.5% of the GC patients within 1 year after partial gastrectomy. Further investigation in a larger cohort is needed to elucidate the underlying mechanisms.

Clinical significance of sarcopenia in patients undergoing treatment for gastric cancer

OBJECTIVE

The aim of this study was to investigate the impact of sarcopenia on prognosis in patients with gastric cancer in order to explore the relationship between sarcopenia and postoperative complications as well as durations of hospital stay and intensive care unit.

METHODS

A total of 175 patients who visited the oncology clinic between 2017 and 2022 with respect to their radiological images, demographic data, and laboratory parameters were perused. The OsiriX software was used to measure the skeletal muscle area that was divided by the body height in order to obtain the skeletal muscle index.

RESULTS

A total of 50.28% of 175 patients (41 females and 134 males, with a mean age of 63.5 years) who met the inclusion criteria in the study were sarcopenic. Significant differences appeared between sarcopenic and non-sarcopenic patients with respect to durations of both hospital stay (p<0.01) and intensive care unit stay (p<0.01) (multivariate analysis). Furthermore, patients with sarcopenia had significantly frequent postoperative complications in comparison with those without sarcopenia. Among the patients with sarcopenia, decreased levels of hemoglobin and albumin as well as lymphocytes were encountered in terms of inflammatory markers; nevertheless, no significant differences were determined among other inflammatory markers.

CONCLUSION

In patients undergoing treatment for gastric cancer, sarcopenia increases postoperative complications and prolongs hospital and intensive care stays during the treatment process.

CYP19A1 promotes gastric cancer as part of a lipid metabolism-related gene signature related to the response of immunotherapy and prognosis

BACKGROUND

Increasing evidence suggests that the metabolism of lipids plays a crucial role in the progression of gastric cancer. However, the expression of lipid metabolism-related genes (LMGs) still does not serve as a prognostic biomarker in gastric cancer.

METHODS

We obtained transcriptome data for 751 LMGs and divided STAD patients into two subtypes based on differences in LMGs expression. Then, we analyzed genetic changes in two subtypes as well as immune features to determine their differences. We also constructed a prognostic risk model related to LMGs for individualized comprehensive evaluations.

RESULTS

In this study, two lipid metabolic (LM) subtypes were identified anchored in the expression profiles of LMGs. Clinical information, genomic alterations, immune features, and immunotherapy response varied significantly between the two LM subtypes. A risk model based on LMGs was also developed to assess prognosis and distinguish patients with high risk from those at low risk. The prognosis differed significantly between the two risk groups of patients. In STAD patients, the risk score was strongly correlated with genomic alterations and immune profile scores. Also, the risk score was an excellent predictor of immune checkpoint inhibitors (ICIs) response. Anchored in preliminary results derived from the aforementioned bioinformatic analysis, we chose CYP19A1 as our target gene and the expression of CYP19A1 was verified in several common gastric cancer cell lines. Then, we carried out the Western blotting, CCK-8 assay, colony formation assay, wound healing assay, and transwell assay to explore the effects of CYP19A1 on malignant biological behavior, and positive consequences were obtained.

CONCLUSIONS

In this study, STAD patients were divided into two subtypes based on LMGs expression. It is possible to assess the prognosis of a patient and the response to immunotherapy using the established prognostic risk model. A series of basic laboratory experiments also verified the functional role of CYP19A1 in gastric cancer.

Impact of Age at Diagnosis on Clinicopathological Features, Prognosis, and Management of Gastric Cancer: A Retrospective Single-Center Experience from Spain

The impact of age on various aspects of gastric cancer (GC) remains controversial. Clarifying this issue can improve our understanding of the disease, refine risk stratification models, and aid in personalized therapeutic approaches. This study aimed to evaluate the influence of age at diagnosis on the clinicopathological features, prognosis, and management of a specific cohort of Spanish patients with resected GC. The study encompassed 315 patients treated at a single tertiary hospital in Spain, divided into two age-based subgroups: ≤65 years and >65 years. The mean and median ages at diagnosis were 72 and 76 years. Most tumors were diagnosed at pT3 stage (49.2%), and 59.6% of patients had lymph node metastases. 21.3% of cases were diagnosed with GC at age ≤ 65 years. Younger patients showed a significantly higher prevalence of flat, diffuse, high-grade tumors, signet-ring cells, perineural infiltration, D2 lymphadenectomies, and adjuvant therapy. They also exhibited a higher rate of recurrences, but had a significantly longer follow-up. Kaplan-Meier curves indicated no significant prognostic differences based on age. Finally, age did not independently predict overall survival or disease-free survival. Our results suggest that younger patients may require more aggressive treatment due to adverse clinicopathologic features, but the lack of prognostic differences among age groups in our cohort indicates the need for further investigation into the complex interplay between age, clinicopathologic factors, and long-term outcomes in GC.

PFDN2 promotes cell cycle progression via the hnRNPD-MYBL2 axis in gastric cancer

Gastric cancer (GC) is a major health burden worldwide, but our understanding of GC is limited, and the prognosis is poor. Novel therapeutic strategies and biomarkers are urgently needed to improve GC patient outcomes. Previously, we identified PFDN2 as a novel key gene in gastric cancer based on its differential expression between cancer and normal tissues. However, the role and underlying mechanisms of PFDN2 in GC remain elusive. In this article, we demonstrated that PFDN2 is highly expressed in GC and that upregulation of PFDN2 is associated with the progression of GC. We further found that PFDN2 could promote cell cycle progression by promoting MYBL2 expression. Mechanistically, we demonstrated that PFDN2 could upregulate MYBL2 expression by facilitating the nuclear translocation of hnRNPD, and thus promoting MYBL2 transcriptional program. In conclusion, we found that PFDN2 promotes cell cycle progression via the hnRNPD-MYBL2 axis and may serve as a potential biomarker and therapeutic target for GC.

Minimally Invasive Surgery for Perihilar Cholangiocarcinoma: A Systematic Review of the Short- and Long-Term Results

Surgery and postoperative systemic chemotherapy represent the standard treatment for patients with perihilar cholangiocarcinoma (PHC). Minimally Invasive Surgery (MIS) for hepatobiliary procedures has spread worldwide in the last two decades. Since resections for PHC are technically demanding, the role of MIS in this field is yet to be established. This study aimed to systematically review the existing literature on MIS for PHC, to evaluate its safety and its surgical and oncological outcomes. A systematic literature review on PubMed and SCOPUS was performed according to the PRISMA guidelines. Overall, a total of 18 studies reporting 372 MIS procedures for PHC were included in our analysis. A progressive increase in the available literature was observed over the years. A total of 310 laparoscopic and 62 robotic resections were performed. A pooled analysis showed an operative time ranging from 205.3 ± 23.9 and 840 (770-890) minutes, and intraoperative bleeding between 101.1 ± 13.6 and 1360 ± 809 mL. Minor and major morbidity rates were 43.9% and 12.7%, respectively, with a 5.6% mortality rate. R0 resections were achieved in 80.6% of patients and the number of retrieved lymph nodes ranged between 4 (3-12) and 12 (8-16). This systematic review shows that MIS for PHC is feasible, with safe postoperative and oncological outcomes. Recent data has shown encouraging results and more reports are being published. Future studies should address differences between robotic and laparoscopic approaches. Given the management and technical challenges, MIS for PHC should be performed by experienced surgeons, in high-volume centers, on selected patients.

History and Future of HER2-Targeted Therapy for Advanced Gastric Cancer

Human epidermal growth factor receptor 2 (HER2) is a receptor tyrosine kinase that belongs to the human epidermal growth factor receptor family. It is overexpressed/amplified in approximately 20% of gastric or gastroesophageal junction cancers. HER2 is being developed as a therapeutic target in a variety of cancers, and several agents have been shown to be effective in breast cancer. The development of HER2-targeted therapy for gastric cancer successfully began with trastuzumab. However, while effective in breast cancer, the successive anti-HER2 agents lapatinib, T-DM1, and pertuzumab failed to demonstrate benefits regarding survival in gastric cancer compared with the existing standard therapies. Intrinsic differences lie between gastric and breast cancer in terms of HER2-positive tumor biology, which may make development difficult. Recently, a novel anti-HER2 agent, trastuzumab deruxtecan, was introduced, and the development of HER2-positive gastric cancer agents has been moving to the next stage. This review summarizes the current HER2-targeted therapy for gastric or gastroesophageal cancer in chronological order and describes the promising future of HER2-targeted therapy.

The combined signatures of the tumour microenvironment and nucleotide metabolism-related genes provide a prognostic and therapeutic biomarker for gastric cancer

The tumour microenvironment (TME) is vital to tumour development and influences the immunotherapy response. Abnormal nucleotide metabolism (NM) not only promotes tumour cell proliferation but also inhibits immune responses in the TME. Therefore, this study aimed to determine whether the combined signatures of NM and the TME could better predict the prognosis and treatment response in gastric cancer (GC). 97 NM-related genes and 22 TME cells were evaluated in TCGA-STAD samples, and predictive NM and TME characteristics were determined. Subsequent correlation analysis and single-cell data analysis illustrated a link between NM scores and TME cells. Thereafter, NM and TME characteristics were combined to construct an NM-TME classifier. Patients in the NMlow/TMEhigh group exhibited better clinical outcomes and treatment responses, which could be attributed to the differences in immune cell infiltration, immune checkpoint genes, tumour somatic mutations, immunophenoscore, immunotherapy response rate and proteomap. Additionally, the NMhigh/TMElow group benefited more from Imatinib, Midostaurin and Linsitinib, while patients in the NMlow/TMEhigh group benefited more from Paclitaxel, Methotrexate and Camptothecin. Finally, a highly reliable nomogram was developed. In conclusion, the NM-TME classifier demonstrated a pretreatment predictive value for prognosis and therapeutic responses, which may offer novel strategies for strategizing patients with optimal therapies.

Differential expression of lysine acetylation proteins in gastric cancer treated with a new antitumor agent bioactive peptide chelate selenium

The method of anticancer bioactive peptide (ACBP) functionalized selenium particle (Se), which has enhanced anticancer activity, inhibited the growth of gastric cancer (GC) cells, and increased the ability of apoptosis in vitro, has been reported in previous studies. We used tandem mass spectrometry (TMT) labeling to construct a complete atlas of the acetylation-modified proteome in GC MKN-45 cells treated with ACBP-Se. The proteomics data database was searched and analyzed by bioinformatics: Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), functional enrichment, and protein-protein interaction network. Finally, we conducted a quantitative PRM analysis of the selected target-modified peptides. We identified 4,958 acetylation sites from 1,926 proteins in this research. Among these, 4,467 acetylation sites corresponding to 1,777 proteins were quantified. Based on the above data and standards, we found that in the ACBP-Se group vs. the control group, 297 sites were upregulated, and 665 sites were downregulated. We systematically assessed the proteins containing quantitative information sites, including protein annotation, functional classification, and functional enrichment, cluster analysis supported by functional enrichment, domain structures, and protein interaction networks. Finally, we evaluated differentially expressed lysine acetylation sites. We revealed that SHMT2 K200 and PGK1 K97 were the most critical acetylated non-histone proteins, which may have an essential role in ACBP-Se treatment. Here, we identified and quantified the lysine acetylation proteins in GC cells treated with ACBP-Se. The characterization of acetylation indicates that acetylated proteins might be pivotal in the biological process, molecular binding, and metabolic pathways of ACBP-Se treatment progress. Our findings provide a broad understanding of acetylation ACBP-Se treatment of GC, suggesting a potential application for molecular targeted therapy.

A telomerase regulation-related lncRNA signature predicts prognosis and immunotherapy response for gastric cancer

BACKGROUND

Telomeres are involved in the development and progression of gastric cancer (GC). However, the association of telomerase regulation-related lncRNAs with prognosis and immunotherapy responsiveness in gastric cancer is unclear.

METHODS

This study systematically evaluated the relationship between lncRNAs co-expressed with 67 telomerase regulatory genes and gastric cancer prognosis. The risk scores of the samples were calculated based on telomerase regulation-related lncRNAs with prognostic value, and the samples were classified into high-/low-risk groups. The prognostic value of risk groups was then evaluated, a GC prognostic prediction model based on risk groups and clinical characteristics was established, and the prediction accuracy of the model was clarified by receiving operating characteristic (ROC) curves and calibration curves. Finally, the value of risk grouping in GC immunotherapy sensitivity was predicted by comparing MSI status and tumor mutation load between the high- and low-risk groups.

RESULTS

We identified 13 lncRNAs with prognostic value co-expressed with telomerase regulatory genes and observed that the prognosis of the low-risk group was significantly better than that of the high-risk group. Meanwhile, a GC overall survival (OS) prediction model based on risk grouping and clinical characteristics was developed, and ROC curves and calibration curves confirmed the good predictive ability of the model. In addition, the low-risk group exhibited a higher tumor mutation load and MSI-H, suggesting a possible benefit of immunotherapy.

CONCLUSION

We found that telomerase regulation-related lncRNAs have prognostic value in GC patients and contribute to the exploration of more effective immunotherapeutic strategies.

Immunohistochemical Analysis of Nicotinamide Phosphoribosyltransferase Expression in Gastric and Esophageal Adenocarcinoma (AEG)

Nicotinamide phosphoribosyltransferase (NAMPT) represents a major component in cellular energy metabolism, which is also crucial for cancer cells that have elevated aerobic glycolysis; moreover, targeting the NAD salvage pathway by inhibition of NAMPT was shown effective in a subgroup of gastric cancer cell lines. In order to study the expression levels of NAMPT in adenocarcinoma of the esophagogastric junction and stomach (AEG/S) we performed immunohistochemical analysis in a cohort of 296 tumor samples using tissue-microarrays (TMAs). In the present investigation, we saw a high expression of NAMPT in only a minority of our large AEG/S cohort. Although we did not find a correlation between NAMPT expression and survival, subgroup analysis showed that NAMPT expression was more frequent in older patients (>65 years, p = 0.049) and was associated with a numerical shorter survival that did not reach statistical significance within this age group. In conclusion, we did not find significance for any prognostic effect of NAMPT in our AEG/S cohort; however, the evaluation of other NAD metabolic enzymes is needed as molecular predictors of response to potential NAMPT inhibition in the treatment of patients with AEG/S.

Features of gastric cancer by anatomic subsite in northern China: A multi-center Health Science Report database study

BACKGROUND

The features of gastric cancer based on the anatomic site remain unknown in northern China patients.

AIM

To analyze gastric cancer features and associated trends based on the anatomical site in northern China patients.

METHODS

This cross-sectional study used incident gastric cancer case data from 10 Peking University-affiliated hospitals (2014 to 2018). The clinical and prevailing local features were analyzed.

RESULTS

A total of 10709 patients were enrolled, including antral (42.97%), cardia (34.30%), and stomach body (18.41%) gastric cancer cases. Cancer in the cardia had the highest male:female ratio, proportion of elderly patients, and patients with complications, including hypertension, diabetes, cerebrovascular, and coronary diseases (P < 0.001). gastric cancer involving the antrum showed the lowest proportion of patients from rural areas and accounted for the highest hospitalization rate and cost (each P < 0.001). The proportion of patients with cancer involving the cardia increased with an increase in the number of gastroesophageal reflux disease cases during the same period (P < 0.001). Multivariate analysis revealed that tumor location in the cardia increased the risk of in-hospital mortality (P = 0.046). Anatomical subsite was not linked to postoperative complications.

CONCLUSION

The features of gastric cancer based on the anatomical site differ between northern China and other regions, both globally and within the country. Social factors may account for these differences and should affect policy-making and clinical practice.

Gastric cancer screening: a systematic review and meta-analysis

BACKGROUND AND AIMS

Gastric cancer (GC) screening is recommended in high-risk populations, although screening methods and intervals vary. In intermediate-risk populations, screening through esophagogastroduodenoscopy (EGD) may be considered depending on local resources. The aim of this study was to compare GC screening methods regarding effect on mortality, diagnostic yield and adherence.

METHODS

Systematic review and meta-analysis including studies evaluating population-based GC screening. Search was conducted in three online databases (MEDLINE, Scopus and clinicaltrials.gov), along with manual search.

RESULTS

Forty-four studies were included. Studies in upper gastrointestinal series (UGIS) demonstrated that GC screening was associated with significantly lower GC mortality rates (OR 0.63, 95% CI 0.55 - 0.73). Benefits on mortality were also found in EGD and serum pepsinogen (PG) studies. EGD was associated with significantly higher GC (0.55%, 95% CI 0.39 - 0.75%) and early-GC (EGC) detection rates (0.48%, 95% CI 0.34 - 0.65%) when compared to UGIS (GC 0.19%, 95% CI 0.10 - 0.31%; EGC 0.08%, 95% CI 0.04 - 0.13%) and PG (GC 0.10%, 95% CI 0.05 - 0.16%; EGC 0.10%, 95% CI 0.04 - 0.19%). Non-invasive methods tended to higher adherence rates when compared to EGD. Regardless of the screening method, individualized recruitment performed better.

DISCUSSION

Screening positively impacted GC mortality rates. EGD was associated with higher diagnostic yield, while UGIS and PG tended to higher adherence rates. Screening uptake was predominantly impacted by recruitment strategies independently of the adopted method.

Secretome analysis reveals reduced expression of COL4A2 in hypoxic cancer-associated fibroblasts with a tumor-promoting function in gastric cancer

BACKGROUND

Cancer-associated fibroblasts (CAFs) are major components of the tumor microenvironment (TME). Hypoxic TME is known to promote tumor progression. However, how a hypoxic condition regulates CAFs remains elusive.

METHODS

To investigate the underlying mechanism involved in the regulation of gastric cancer (GC) progression by hypoxic CAFs, we performed secretome profiling. Normoxic or hypoxic CAFs conditioned media (CM) were filter-concentrated and in-gel trypsin digested. Resulting peptides were analyzed with LC-MS/MS.

RESULTS

We observed that CM derived from hypoxic CAFs could promote migration of a panel of GC cell lines (AGS, SNU668, SNU638). Mass spectrometry analysis of hypoxic or normoxic CAFs CM identified 1595 proteins, of which 19 proteins (10 upregulated and 9 downregulated) were differentially expressed in the hypoxic secretome. We focused on COL4A2, whose expression was significantly decreased in hypoxic CAFs in HIF-1α-independent manner. Silencing of COL4A2 expression in normoxic CAFs phenocopied the effect of hypoxic CAFs in promoting GC cell migration.

CONCLUSIONS

The reduced expression of COL4A2 in a hypoxic environment might be associated with the tumor-promoting role of hypoxic CAFs in GC.

Treatment response, survival, and safety profile of camrelizumab plus apatinib regimen as third-line treatment in metastatic gastric cancer patients

BACKGROUND

Camrelizumab, as a PD-1 inhibitor on the market recently, presents favorable therapeutic efficacy in several advanced cancers, while its application in metastatic gastric cancer (mGC) lacks data. This study aimed to assess treatment response, survival profile, and adverse events of camrelizumab plus apatinib regimen as third-line treatment in mGC patients.

METHODS

Nineteen mGC patients who received camrelizumab plus apatinib as third-line treatment were analyzed in this observational study. Subsequently, treatment response and adverse events were documented, then progression-free survival (PFS) and overall survival (OS) were calculated.

RESULTS

No (0.0%) patient achieved complete response; 5 (26.3%) patients achieved partial response; 8 (42.1%) patients had stable disease; 6 (31.6%) patients had progressive disease, resulting in objective response rate and disease control rate of 26.3% and 68.4%, respectively. Meanwhile, the median PFS and OS were 7.0 (95%CI: 2.9-11.0) months and 10.0 (95%CI: 7.4-12.6) months, accordingly. Besides, multiple metastases linked with worse PFS (P = 0.029) and OS (P = 0.021); Eastern Cooperative Oncology Group performance status (ECOG PS) score 1 (vs. 0) related to shorter OS (P = 0.030). Worth noting, the common adverse events were fatigue (42.1%), anemia (42.1%), neutropenia (42.1%), leukopenia (36.8%), pruritus (31.6%), proteinuria (31.6%), nausea and vomiting (31.6%), reactive capillary hemangioma (31.6%) and thrombocytopenia (31.6%). Meanwhile, grade 3-4 adverse events only included: thrombocytopenia (5.3%), hypertension (5.3%), and proteinuria (5.3%).

CONCLUSION

Camrelizumab plus apatinib as third-line treatment achieves satisfactory therapeutic efficacy and survival profile with generally manageable adverse events in mGC patients.

Circular RNA EIF4G3 suppresses gastric cancer progression through inhibition of β-catenin by promoting δ-catenin ubiquitin degradation and upregulating SIK1

BACKGROUND

Increasing studies suggest that circular RNAs (circRNAs) are critical regulators of cancer development and progression. However, the biological roles and mechanisms of circRNAs in gastric cancer (GC) remain largely unknown.

METHODS

We identified the differentially expressed circRNAs in GC by analyzing Gene Expression Omnibus (GEO) datasets. We explored the biological roles of circRNAs in GC by in vitro functional assays and in vivo animal studies. We performed tagged RNA affinity purification (TRAP), RNA immunoprecipitation (RIP), mass spectrometry (MS), RNA sequencing, luciferase reporter assays, and rescue experiments to investigate the mechanism of circRNAs in GC.

RESULTS

Downregulated expression of circular RNA EIF4G3 (circEIF4G3; hsa_circ_0007991) was found in GC and was associated with poor clinical outcomes. Overexpression of circEIF4G3 suppressed GC growth and metastasis through the inhibition of β-catenin signaling, whereas knockdown of circEIF4G3 showed the opposite effects. Mechanistic studies revealed that circEIF4G3 bound to δ-catenin protein to promote its TRIM25-mediated ubiquitin degradation and interacted with miR-4449 to upregulate SIK1 expression.

CONCLUSION

Our findings uncovered a tumor suppressor function of circEIF4G3 in GC through the regulation of δ-catenin protein stability and miR-4449/SIK1 axis. CircEIF4G3 may act as a promising prognostic biomarker and therapeutic target for GC.

Gastric cancer incidence and mortality trends 2007-2016 in three European countries

BACKGROUND : Increased awareness of gastric cancer risk, easy access to upper endoscopy, and high definition endoscopes with virtual chromoendoscopy may have led to the increase in early diagnosis of gastric cancer observed in recent years in Europe, which may be associated with improved survival. Currently, no data exist on the impact of early diagnosis on survival at a populational level in Europe. Our aim was to assess gastric cancer incidence, early diagnosis, and survival in northwestern and southern European countries with a low-to-moderate incidence of gastric cancer. METHODS : Data on 41 138 gastric cancers diagnosed in 2007-2016 were retrieved from national cancer registries of Belgium, the Netherlands, and northern Portugal. Age-standardized incidence and mortality rates were assessed and expressed per 100 000 person-years. Early diagnosis was defined as T1 tumors. Net survival estimates for 2007-2011 vs. 2012-2016 were compared. RESULTS : Age-standardized incidence and mortality decreased over time in Belgium, northern Portugal, and the Netherlands (relative incidence decrease 8.6 %, 4.5 %, and 46.8 %, respectively; relative mortality decrease 22.0 %, 30.9 %, and 50.0 %, respectively). Early gastric cancer diagnosis increased over time for all countries. Net 1-year survival improved significantly between the two time periods in all countries, and at 5 years in Belgium and Portugal. CONCLUSIONS : This is the first study comparing trends (2007-2016) in gastric cancer incidence and mortality in some European countries. We found an increasing proportion of T1 gastric cancers and a decrease in age-standardized mortality over time, supporting the use of secondary prevention strategies.

Laparoscopic versus Open Surgery for Gastric Cancer in Western Countries: A Systematic Review and Meta-Analysis of Short- and Long-Term Outcomes

Background. The advantages of a laparoscopic approach for the treatment of gastric cancer have already been demonstrated in Eastern Countries. This review and meta-analysis aims to merge all the western studies comparing laparoscopic (LG) versus open gastrectomies (OG) to provide pooled results and higher levels of evidence. Methods. A systematic literature search was performed in MEDLINE(PubMed), Embase, WebOfScience and Scopus for studies comparing laparoscopic versus open gastrectomy in western centers from 1980 to 2021. Results. After screening 355 articles, 34 articles with a total of 24,098 patients undergoing LG (5445) or OG (18,653) in western centers were included. Compared to open gastrectomy, laparoscopic gastrectomy has a significantly longer operation time (WMD = 47.46 min; 95% CI = 31.83−63.09; p < 0.001), lower blood loss (WMD = −129.32 mL; 95% CI = −188.11 to −70.53; p < 0.0001), lower analgesic requirement (WMD = −1.824 days; 95% CI = −2.314 to −1.334; p < 0.0001), faster time to first oral intake (WMD = −1.501 days; 95% CI = −2.571 to −0.431; p = 0.0060), shorter hospital stay (WMD = −2.335; 95% CI = −3.061 to −1.609; p < 0.0001), lower mortality (logOR = −0.261; 95% the −0.446 to −0.076; p = 0.0056) and a better 3-year overall survival (logHR 0.245; 95% CI = 0.016−0.474; p = 0.0360). A slight significant difference in favor of laparoscopic gastrectomy was noted for the incidence of postoperative complications (logOR = −0.202; 95% CI = −0.403 to −0.000 the = 0.0499). No statistical difference was noted based on the number of harvested lymph nodes, the rate of major postoperative complication and 5-year overall survival. Conclusions. In Western centers, laparoscopic gastrectomy has better short-term and equivalent long-term outcomes compared with the open approach, but more high-quality studies on long-term outcomes are required.

Molecular Characteristics, Clinical Significance, and Cancer Immune Interactions of Angiogenesis-Associated Genes in Gastric Cancer

Background

Immunotherapy has evolved as a critical option to treat diverse cancers. The active response to immunotherapy relies on the unique interaction between cancer and the tumor microenvironment (TME). Angiogenesis is one of the hallmarks of cancer. However, the association between angiogenesis and clinical outcome, immune cell infiltration, and immunotherapy remains unknown in gastric cancer (GC).

Methods

We systematically assessed 36 angiogenesis-associated genes (AAGs) and comprehensively identified the correlation between angiogenesis and transcriptional patterns, prognosis, and immune cell infiltration. The AAG_score was applied to quantify the angiogenesis subtypes of each patient. We then evaluated their values in prognostic prediction and therapeutic responses in GC.

Results

We discussed the mutations of AAGs in GC specimens from genetic levels and identified their expression patterns from TCGA and GEO cohorts. We determined two different molecular subtypes and observed that AAG mutations were related to patients’ clinicopathological characteristics, prognosis, and infiltrating TME. Next, an AAG_score for predicting overall survival (OS) was established and its reliable predictive ability in GC patients was confirmed. Furthermore, we created a highly reliable nomogram to facilitate the clinical viability of the AAG_score. A low AAG_score, characterized by elevated microsatellite instability-high, mutation burden, and immune activation, demonstrated a superior OS. Additionally, the AAG_score was remarkedly correlated with the cancer stem cell index and drug susceptibility.

Conclusion

Collectively, we identified a prognostic AAG signature for GC patients. This signature may contribute to clarifying the characteristics of TME and enable the exploration of more potent immunotherapy strategies.

Upregulated Circular RNA KIF4A Promotes Cell Migration and Invasion by Regulating MicroRNA-144-3p/EZH2 Axis in Gastric Cancer

Accumulating evidence has shown that circular RNAs (circRNAs) serve a critical regulatory role in various human cancers, including gastric cancer (GC), and in this study, we aimed to explore the functions of circKIF4A in the progression of GC. Our findings demonstrated that circKIF4A was highly expressed in both GC tissues and cell lines, and high intratumoral circKIF4A expression predicted a poor prognosis in GC patients. In vitro gain- and loss-of-function assays indicated that circKIF4A knockdown suppressed the proliferation, migration, invasion, and EMT of GC cells, while these malignant behaviors were enhanced by circKIF4A overexpression. Mechanistically, we found that circKIF4A was mainly located in the cytoplasm, could directly interact with microRNA- (miR-) 144-3p, and functions as a miRNA sponge to regulate EZH2 expression in GC cells. miR-144-3p inhibition or EZH2 restoration largely blocked the effects of circKIF4A knockdown on the malignant behaviors of GC cells. This study indicated that circKIF4A can efficiently sponge miR-144-3p to promote the malignant behaviors of GC cells and may provide a potential biomarker and therapeutic target for GC management.

Decreased Expression of Cell Adhesion Molecule 4 in Gastric Adenocarcinoma and Its Prognostic Implications

Cell adhesion molecule 4 (CADM4) is a novel tumor suppressor candidate. The prognostic implications of CADM4 in gastric cancer have not been conclusively elucidated. Therefore, we evaluated the clinicopathological significance and prognostic value of CADM4 expression in a large series of patients with gastric adenocarcinoma. Immunohistochemical staining for CADM4 was performed on 534 gastric adenocarcinomas. We evaluated the associations between CADM4 expression and the clinicopathological and molecular characteristics of the adenocarcinomas. The prognostic effect of CADM4 expression was evaluated by survival analyses. Low CADM4 expression was significantly associated with young age (p = 0.046), aggressive histological type (p < 0.001), high pT category (p < 0.001), nodal metastasis (p < 0.001), high stage (p = 0.002), lymphovascular invasion (p = 0.001), and perineural invasion (p = 0.001). Low CADM4 expression was more frequently observed in tumors without human epidermal growth factor receptor 2 (HER2) amplification (p = 0.002). Low CADM4 expression was associated with worse overall survival (p = 0.007) and recurrence-free survival (p = 0.005) in the survival analyses. Low CADM4 expression was associated with aggressive clinicopathological features and poor clinical outcomes. CADM4 can act as a tumor suppressor in gastric adenocarcinoma and can be considered a prognostic biomarker.

PSMC2 promotes the progression of gastric cancer via induction of RPS15A/mTOR pathway

As one of the most common malignant tumors, it is particularly important to further understand the development mechanism of gastric cancer and to find more effective therapeutic target genes. The results of immunohistochemical staining showed that PSMC2 was upregulated in gastric cancer. Cell function experiments indicated that PSMC2 knockdown inhibited the proliferation, clone formation and migration of gastric cancer cells, and induced apoptosis. In vivo experiments further showed that PSMC2 knockdown suppressed tumor growth. RPS15A and mTOR pathway were identified the downstream gene and pathway of PSMC2 by GeneChip and IPA. PSMC2 knockdown inhibited RPS15A expression and mTOR pathway, which was neutralized by RPS15A overexpression. Overexpression of RPS15A promoted the proliferation and migration of gastric cancer cells, which alleviated the inhibitory effect caused by PSMC2 knockdown to a certain extent. The mTOR pathway inhibitor Torin1 partially restored the promoting role of RPS15A overexpression on the gastric cancer cell proliferation. Furthermore, bioinformatics analysis and dual-luciferase reporter assays showed that PSMC2 and RPS15A competitively bound to hsa-let-7c-3p. Inhibition of hsa-let-7c-3p promoted the migration of MGC-803 cells and reduced the apoptosis level, while simultaneous inhibition PSMC2 and hsa-let-7c-3p restored the migration and apoptosis levels of gastric cancer cells. In conclusion, PSMC2 and RPS15A were highly expressed in gastric cancer. PSMC2 enhanced RPS15A levels by targeting hsa-let-7c-3p, and then activated mTOR pathway, thereby promoting the progression of gastric cancer.

Comparison of Treatment Efficacy and Survival Outcomes Between Asian and Western Patients With Unresectable Gastric or Gastro-Esophageal Adenocarcinoma: A Systematic Review and Meta-Analysis

Background

Gastric cancer and gastro-esophageal adenocarcinoma are geographically heterogeneous diseases. Previous studies suggested that Asian and Western patients with late-stage gastric or gastro-esophageal adenocarcinoma possess distinct survival outcomes. However, the interregional differences of multiple systemic therapies in unresectable diseases have not been comprehensively described.

Materials and Methods

We searched PubMed-MEDLINE, Embase, Web of Science and Cochrane Library from inception to 31 October 2021 and reviewed major conference abstracts for controlled trials of systemic therapies in unresectable gastric or gastro-esophageal adenocarcinoma that reported hazard ratios stratified by geographical region. The primary measurements were overall survival and progression-free survival. The pooled hazard ratios and 95% confidence intervals for overall survival and progression-free survival in Asian and Western populations were calculated using a random effect model. A linear regression model was adopted to compare the overall survival and progression-free survival between Asian and Western patients.

Results

A total of 9033 patients from 20 studies were included for analysis. Immunotherapy was associated with an improvement in the overall survival for both Asian (hazard ratio, 0.80; 95% confidence interval, 0.65–0.98) and Western (hazard ratio, 0.90; 95% confidence interval, 0.81–1.00) patients, with no significant difference between the two groups (P = 0.32). Trends of survival benefit with anti-HER2 therapy and anti-angiogenic therapy versus control were observed in both Asian and Western patients, although statistical significance was not denoted. Subgroup analyses yielded a statistically superior overall survival of Asian versus Western patients in trials that investigated first-line immunotherapy (P = 0.04). Due to the linear regression analyses with scatter plot graphs, Asian patients showed a higher overall survival, but not progression-free survival, than Western patients irrespective of treatment type.

Conclusion

Asian and Western patients with unresectable gastric or gastro-esophageal adenocarcinoma show similar responses to systemic therapies with limited interregional differences. Exceptionally, first-line immunotherapy could elicit superior survival among Asian populations. In addition, Asian patients with gastric or gastro-esophageal adenocarcinoma display a superior OS compared with Western counterparts.

Novel Risk Associations between microRNA Polymorphisms and Gastric Cancer in a Chilean Population

Gastric cancer (GC) is the fifth leading cause of cancer deaths in the world, with variations across geographical regions and ethnicities. Emerging evidence indicates that miRNA expression is dysregulated in GC and its polymorphisms may contribute to these variations, which has yet to be explored in Latin American populations. In a case-control study of 310 GC patients and 311 healthy donors from Chile, we assessed the association of 279 polymorphisms in 242 miRNA genes. Two novel polymorphisms were found to be associated with GC: rs4822739:C>G (miR-548j) and rs701213:T>C (miR-4427). Additionally, rs1553867776:T>TCCCCA (miR-4274) and rs12416605:C>T (miR-938) were associated with intestinal-type GC, and rs4822739:C>G (miR-548j) and rs1439619:T>G (miR-3175) with TNM I-II stage. The polymorphisms rs6149511:T> TGAAGGGCTCCA (miR-6891), rs404337:G>A (miR-8084), and rs1439619:T>G (miR-3175) were identified among H.pylori-infected GC patients and rs7500280:T>C (miR-4719) and rs1439619:T>G (miR-3175) were found among H. pylori cagPAI+ infected GC cases. Prediction analysis suggests that seven polymorphisms could alter the secondary structure of the miRNA, and the other one is located in the seed region of miR-938. Targets of miRNAs are enriched in GC pathways, suggesting a possible biological effect. In this study, we identified seven novel associations and replicated one previously described in Caucasian population. These findings contribute to the understanding of miRNA genetic polymorphisms in the GC pathogenesis.

circABCB10 Promotes Malignant Progression of Gastric Cancer Cells by Preventing the Degradation of MYC

Objective

To investigate the role of circABCB10 in gastric cancer and the molecular mechanism of promoting malignant progression of gastric cancer cells by preventing the degradation of MYC by hsa-miR-1252-5p.

Methods

The expression of circABCB10 in gastric cancer tissues and cells was detected by real-time quantitative PCR. MTT, Transwell, clone formation, and TUNEL assay were used to detect the effects of circABCB10 on the proliferation, invasion, and apoptosis of gastric cancer cells. A subcutaneous tumor-bearing model was established to study the inhibitory effect of knockdown circABCB10 on gastric cancer proliferation. The dual luciferase reporter gene assay and RNA pull-down assay were used to verify the regulatory effect of circABCB10 on miR-1252-5p and the regulatory effect of miR-1252-5p on MYC.

Results

Compared with paracancerous tissues and gastric mucosal epithelial cells, the expression of circABCB10 was significantly increased in human gastric cancer tissues and gastric cancer cells. circABCB10 knockout significantly decreased cell viability and invasion ability and promoted cell apoptosis (P < 0.01). Subcutaneous tumor-bearing experiments in nude mice demonstrated that circABCB10 knockdown inhibited the proliferation of gastric cancer cells. circABCB10 can act as a sponge for miR-1252-5p in gastric cancer cells. Meanwhile, MYC is the target gene of miR-1252-5p. Overexpression of miR-1252-5p and knockdown of MYC reversed the promoting effect of circABCB10 on gastric cancer.

Conclusion

circABCB10 can promote the proliferation, invasion, and clonal formation of gastric cancer cells by targeting miR-1252-5p and upregulating the expression of MYC. circABCB10/miR-1252-5p/MYC constitutes the regulatory mechanism of ceRNA.

Discovery and Validation of an Epithelial-Mesenchymal Transition-Based Signature in Gastric Cancer by Genomics and Prognosis Analysis

Objective

Epithelial-mesenchymal transition (EMT) exerts a key function in cancer initiation and progression. Herein, we aimed to develop an EMT-based prognostic signature in gastric cancer.

Methods

The gene expression profiles of gastric cancer were obtained from TCGA dataset as a training set and GSE66229 and GSE84437 datasets as validation sets. By LASSO regression and Cox regression analyses, key prognostic EMT-related genes were screened for developing a risk score (RS) model. Potential small molecular compounds were predicted by the CMap database based on the RS model. GSEA was employed to explore signaling pathways associated with the RS. ESTIMATE and seven algorithms (TIMER, CIBERSORT, CIBERSORT-ABS, QUANTISEQ, MCPCOUNTER, XCELL, and EPIC) were applied to assess the RS and immune microenvironment.

Results

This study developed an EMT-related gene signature comprised of SERPINE1, PCOLCE2, MATN3, and DKK1. High-RS patients displayed poorer survival outcomes than those with low RS. ROC curves demonstrated the robustness of the model in predicting the prognosis. After external validation, the RS model was an independent risk factor for gastric cancer. Several compounds were predicted for gastric cancer treatment based on the RS model. ECM receptor interaction, focal adhesion, pathway in cancer, TGF-beta, and WNT pathways were distinctly activated in high-RS samples. Also, high RS was significantly associated with increased stromal and immune scores and increased infiltration of CD4+ T cell, CD8+ T cell, cancer-associated fibroblast, and macrophage in gastric cancer tissues.

Conclusion

Our findings suggested that the EMT-related gene model may robustly predict gastric cancer prognosis, which could improve the efficacy of personalized therapy.

Contribution of upregulated aminoacyl-tRNA biosynthesis to metabolic dysregulation in gastric cancer

BACKGROUND AND AIM

Metabolic reprogramming is characterized by dysregulated levels of metabolites and metabolic enzymes. Integrated metabolomic and transcriptomic data analysis can help to elucidate changes in the levels of metabolites and metabolic enzymes, screen the core metabolic pathways, and develop novel therapeutic strategies for cancer.

METHODS

Here, the metabolome of gastric cancer tissues was determined using liquid chromatography-mass spectrometry. The transcriptome data from The Cancer Genome Atlas dataset were integrated with the liquid chromatography-mass spectrometry data to identify the common dysregulated gastric cancer-specific metabolic pathways. Additionally, the protein expression and clinical significance of key metabolic enzymes were examined using a gastric cancer tissue array.

RESULTS

Metabolomic analysis of 16 gastric cancer tissues revealed that among the 15 dysregulated metabolomic pathways, the aminoacyl-tRNA biosynthesis pathway in the gastric tissues was markedly upregulated relative to that in the adjacent noncancerous tissues, which was consistent with the results of transcriptome analysis. Bioinformatic analysis revealed that among the key regulators in the aminoacyl-tRNA biosynthesis pathway, the expression levels of threonyl-tRNA synthetase (TARS) and phenylalanyl-tRNA synthetase (FARSB) were correlated with tumor grade and poor survival, respectively. Additionally, gastric tissue array data analysis indicated that TARS and FARSB were upregulated in gastric cancer tissues and were correlated with poor prognosis and tumor metastasis.

CONCLUSIONS

This study demonstrated that the aminoacyl-tRNA biosynthesis pathway is upregulated in gastric cancer and both TARS and FARSB play key roles in the progression of gastric cancer. Additionally, a novel therapeutic strategy for gastric cancer was proposed that involves targeting the aminoacyl-tRNA biosynthesis pathway.

RNF144A-AS1, a TGF-β1- and hypoxia-inducible gene that promotes tumor metastasis and proliferation via targeting the miR-30c-2-3p/LOX axis in gastric cancer

Background

Although recent molecular analyses have improved our knowledge regarding gastric cancer (GC) biology, the molecular mechanisms that confer metastatic potential to GC remain poorly understood. In this study, we intend to explore the function and characterize the underlying mechanism of long noncoding RNA RNF144A-AS1 in GC metastasis and outgrowth.

Methods

The expression of RNF144A-AS1, miR-30c-2-3p, and Lysyl oxidase (LOX) was detected by quantitative real-time PCR assay. Fluorescence in situ hybridization and subcellular fractionation assay determined the cellular localization of RNF144A-AS1. Cell counting kit 8 assay, transwell assay, and tube formation assay were performed to detect the effect on cell proliferation, migration, invasion, and angiogenesis, respectively. Animal models were also applied to verify the effect on tumor metastasis, outgrowth, and angiogenesis. Bioinformatic analysis, luciferase reporter assay, and RNA immunoprecipitation (RIP) assay explored the interactions among RNF144A-AS1, miR-30c-2-3p, and LOX. Gene regulation was further validated by knockdown of Dicer or mutating the miRNA binding sites on RNF144A-AS1 and LOX 3ʹUTR. Cells were treated with recombinant human TGF-β1 (Transforming Growth Factor β1) to explore the effect of TGF-β1 on RNF144A-AS1. Western blot and immunohistochemistry were used to detect protein expression.

Results

The expression of RNF144A-AS1 was significantly upregulated in GC tissues and was associated with poor prognosis and later-stage diseases. Hypoxia stimulated the expression of RNF144A-AS1 in a HIF-1α-independent manner. Additionally, RNF144A-AS1 was also induced by TGF-β1. Loss and gain of function assays revealed that RNF144A-AS1 promoted tumor metastasis, angiogenesis, and proliferation. Mechanism exploration indicated RNF144A-AS1 served as a microRNA decoy of miR-30c-2-3p to release LOX. Gene Set Enrichment Analysis further suggested LOX and RNF144A-AS1 were enriched in the same gene sets, emphasizing the internal mechanism connection between these two genes.

Conclusions

TGF-β1- and hypoxia-inducible RNF144A-AS1 promoted tumor metastasis, angiogenesis, and proliferation through targeting the miR-30c-2-3p/LOX axis in GC, highlighting the value of the RNF144A-AS1/miR-30c-2-3p/LOX axis in therapeutic interventions of GC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13578-021-00689-z.

The rs9953490 polymorphism of DAL-1 gene is associated with gastric cancer risk in the Han population in Northeast China

Background

DAL-1 gene was reported to inhibit proliferation, migration, invasion, and epithelial to mesenchymal transition (EMT) of gastric cancer (GC) cells in our previous study. The association between the genomic variants in DAL-1 gene with risk of GC is still unclear.

Methods

In this study, 505 GC cases and 544 healthy controls (HCs) were collected to evaluate the association between six single nucleotide polymorphisms (SNPs) (rs7240736, rs73937194, rs3817466, rs8082898, rs73381527, rs9953490) of DAL-1 gene and GC risk in the Han population in Northeast China.

Results

The TA + AA genotypes of rs9953490 were significantly associated with an increased risk in N3 compared with N0 subgroup (adjusted OR = 4.56, 95% CI = 1.49–13.98, P = 0.008), and also showed evident association with an increased risk in TNM stage III compared with stage I-II (adjusted OR = 2.33, 95% CI = 1.16–4.67, P = 0.017).

Conclusion

The rs9953490 of DAL-1 gene may play an important role in the occurrence and development of GC in the Han population in Northeast China.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-01929-9.

Comparison of laparoscopic surgery with open standard surgery for advanced gastric carcinoma in a single institute: a propensity score matching analysis

BACKGROUND

Compared with open standard gastrectomy (OG), laparoscopic gastrectomy (LG) did not result in inferior disease-free survival for early-stage and locally advanced gastric cancer (AGC). However, whether LG for AGC in elderly patients is more beneficial than OG is unclear.

METHODS

This study examined 458 patients with AGC. The mortality, morbidity, and prognosis were compared by age, gender, T and N factors, and pathological stage in the LG and OG groups using propensity score matching analysis. For the final analysis, 151 pairs of patients were selected from at each group.

RESULTS

The results showed that no significant difference in mortality and morbidity existed between the two groups. The 5-year relapse-free survival (RFS) rates were 70% and 62% in the LG and OG groups, respectively (p = 0.104). The 5-year RFS rates in patients with pathological stages I, II, and III who had undergone LG were 84%, 80%, and 55%, respectively, and 78%, 70%, and 45%, respectively, in those who had undergone OG (p < 0.005). The 5-year RFS rates in nonelderly patients who underwent LG or OG were 75% and 68%, respectively, and 58% and 40%, respectively, in elderly patients who underwent LG or OG (p < 0.005).

CONCLUSION

The 5-year RFS rates in patients with AGC at each stage did not significantly differ between LG and OG. However, the benefits at 5-year RFS in patients who underwent LG compared with OG were larger in elderly patients than those in nonelderly patients.

Applying immune-related lncRNA pairs to construct a prognostic signature and predict the immune landscape of stomach adenocarcinoma

Background: Long noncoding RNAs (lncRNAs) are associated with the survival of cancer patients. We constructed an immune-related lncRNA (irlncRNA) pair signature for stomach adenocarcinoma (STAD).Research design and methods: irlncRNAs were identified via coexpression analysis with immune-related genes. Differentially expressed irlncRNAs (DEirlncRNAs) were paired. Least absolute shrinkage and selection operator (LASSO) and multivariate Cox proportional hazards regression methods were used to construct the signature. We calculated the area under the receiver operating characteristic (ROC) curve and determined the best cutoff value according to the Akaike information criterion (AIC). Patients were divided into high - and low-risk groups, and differences in immune cell infiltration, tumor mutation burden (TMB) and drug treatment effects between the groups were explored according to the risk score.Results: An 8-irlncRNA-pair signature was constructed and proven to be a strong prognosis predictor in STAD patients through external verification. Moreover, the risk score was identified as an independent prognostic factor. There were significant differences in immune cell infiltration and the response to several drug treatments between patients with high and low risk scores, and the risk score was negatively correlated with TMB.Conclusions: The signature consisting of 8 irlncRNA pairs showed good prognostic predictive value.