Staging Of Gastric Cancer Research Articles

OGC SO22 - Accuracy of CT and FDG/PET clinical staging within a dedicated multidisciplinary service for patients with oesophago-gastric cancer

Abstract Background Accurate staging for oesophago-gastric cancer is important in ensuring correct treatment pathways, avoiding unnecessary surgery and providing prognostication for patients. Previously, cross sectional imaging in accurately providing tumour (T) and nodal (N) staging has been variable for upper GI malignancies, with usage of invasive investigations such as EUS to provide more specific local staging. With the increased utilisation of specialist multidisciplinary involvement and improved technology, we aimed to assess whether CT and PET imaging may be able to provide sufficiently accurate staging required for treatment decision making. Method All patients who underwent oesoophagogastric resections between January 2022 and March 2024 were identified from our surgical database. Patients were included if they had oesophago-gastric cancer, and underwent curative resection without neo-adjuvant treatment. Data collected included age, gender, location of primary tumour, CT/PET staging, and final histology. Outcomes assessed included rate of understaging in clinical and pathological T and N staging, and sensitivity and specificity of imaging in identifying presence of nodal disease. Results 38 patients were included in this analysis. For oesophageal and GOJ cancers, T stage under-reporting occurred in 6/27 (22%) patients, and N under-reporting in 7/27 (27%) patients. Radiological staging correlated with final pathological staging in 55% of T staging and 59% of N staging. Sensitivity (55.56%, 95% CI 21-86%) and specificity (72.2%, 95% CI 46.5-90.3%) for nodal disease on CT/PET was low, however no tumour or nodal under-staging would have impacted management. Gastric cancer staging accuracy assessment was limited by small numbers (n=12), however T under-staging occurred in 5/12 (42%) patients and N under-staging occurred in 5/11 patients (45%). Conclusion Involvement of dedicated radiology services in multidisciplinary care for oesophago-gastric cancer provides adequate radiological staging to guide treatment. Gastric cancer clinical staging requires laparoscopic and endoscopic assessment for accurate tumour assessment and management guidance. Radiological under-staging is less common in oesophageal and GOJ tumours than gastric cancer and has minimal impact on patient management.

The Advancement Stage of Gastric Cancer and the Levels of CEA and Ca19-9 in Serum and Peritoneal Lavage

Background: This study aimed to analyze the relationship between the levels of tumor markers—specifically, carcinoembryonic antigen (CEA) and Ca19-9 antigen—determined in both serum (sCEA and sCa19-9) and intraoperative peritoneal washings (pCEA and pCa19-9) and the advanced stage of gastric cancer (including the occurrence of cancer cells in cytology from abdominal fluid). Methods: This study included 47 patients with histopathologically confirmed gastric cancer or gastroesophageal junction cancer who underwent surgical treatment. The material for the cytological examination and assessment of CEA and Ca19-9 concentrations in peritoneal fluid was collected intraoperatively. Later, blood was drawn to assess the CEA and Ca19-9 concentrations in blood serum. Results: There was a statistical correlation between a positive cytology result or the presence of peritoneal carcinomatosis and a positive result for the tumor markers obtained from abdominal washings. This correlation was not observed with marker levels obtained from blood serum. The pCEA marker was highly sensitive (93.3%) and specific (93.8%) for detecting cancer cells. The pCa19-9 marker was less effective in detecting cancer but matched pCEA in identifying the absence of cancer. No differences were observed in sCEA and sCA19-9 levels between patients who underwent neoadjuvant chemotherapy and those who did not receive this treatment. However, statistical analysis showed that this relationship did not apply to pCEA and pCa19-9 levels. Conclusions: Intraoperative determinations of tumor marker levels in peritoneal washings may be a predictive factor for a poor prognosis in patients with gastric cancer.

Clinical application of oral contrast-enhanced ultrasound in evaluating the preoperative T staging of gastric cancer.

Oral contrast-enhanced ultrasound (OCEUS) is widely used in the noninvasive diagnosis and screening of gastric cancer (GC) in China. To investigate the clinical application of OCEUS in evaluating the preoperative T staging of gastric cancer. OCEUS was performed before the operation, and standard ultrasound images were retained. The depth of infiltration of GC (T-stage) was evaluated according to the American Joint Committee on Cancer 8th edition of the tumor-node-metastasis staging criteria. Finally, with postoperative pathological staging as the gold standard reference, the sensitivity, specificity, negative predictive value, positive predictive value, and diagnostic value of OCEUS T staging were evaluated. OCEUS achieved diagnostic accuracy rates of 76.6% (T1a), 69.6% (T1b), 62.7% (T2), 60.8% (T3), 88.0% (T4a), and 88.7% (T4b), with an average of 75.5%. Ultrasonic T staging sensitivity exceeded 62%, aside from T1b at 40.3%, while specificity was over 91%, except for T3 with 83.5%. The Youden index was above 60%, with T1b and T2 being exceptions. OCEUS T staging corresponded closely with pathology in T4b (kappa > 0.75) and moderately in T1a, T1b, T2, T3, and T4a (kappa 0.40-0.75), registering a concordance rate exceeding 84%. OCEUS was effective, reliable, and accurate in diagnosing the preoperative T staging of GC. As a noninvasive diagnostic technique, OCEUS merits clinical popularization.

Molecular Mechanism for Malignant Progression of Gastric Cancer Within the Tumor Microenvironment.

Gastric cancer (GC) is one of the most common cancers worldwide. Most patients are diagnosed at the progressive stage of GC, and progress in the development of effective anti-GC drugs has been insufficient. The tumor microenvironment (TME) regulates various functions of tumor cells, and interactions between the cellular and molecular components of the TME-e.g., inflammatory cells, fibroblasts, vasculature cells, and innate and adaptive immune cells-promote the aggressiveness of cancer cells and dissemination to distant organs. This review summarizes the roles of various TME cells and molecules in regulating the malignant progression and metastasis of GC. We also address the important roles of signaling pathways in mediating the interaction between cancer cells and the different components of the GC TME. Finally, we discuss the implications of these molecular mechanisms for developing novel and effective therapies targeting molecular and cellular components of the GC TME to control the malignant progression of GC.

NPR1 promotes cisplatin resistance by inhibiting PARL-mediated mitophagy-dependent ferroptosis in gastric cancer

Cisplatin-based chemotherapy serves as the standard of care for individuals with advanced stages of gastric cancer. Nevertheless, the emergence of chemoresistance in GC has detrimental impacts on prognosis, yet the underlying mechanisms governing this phenomenon remain elusive. Level of mitophagy and ferroptosis of GC cells were detected by fluorescence, flow cytometry, GSH, MDA, Fe2+ assays, and to explore the specific molecular mechanisms between NPR1 and cisplatin resistance by performing western blot and coimmunoprecipitation (co-IP) assays. These results indicates that NPR1 positively correlated with cisplatin-resistance and played a crucial part in conferring resistance to cisplatin in gastric cancer cells. Mechanistically, NPR1 affected levels of mitophagy and ferroptosis in human cisplatin-resistance GC cells with cisplatin treatment. Specifically, NPR1 inhibited mitophagy-dependent ferroptosis by reducing the ubiquitination-mediated degradation of PARL; moreover, NPR1 promoted PARL stabilization by disrupting the PARL–MARCH8 complex, which ultimately led to the development of chemoresistance in GC cells. Considering our findings, NPR1 appears to play an important role in chemotherapy for GC. NPR1 could potentially be used to overcome chemotherapy resistance.Graphical 1. NPR1 is highly expressed in cisplatin-resistant GC cells and promotes the cisplatin resistance.2. According to IP-MS, NPR1 inhibits mitophagy-dependent ferroptosis through its downstream protein PARL.3. NPR1 promoted PARL stabilization by disrupting the PARL–MARCH8 complex to inhibit the ubiquitination-mediated degradation of PARL.

CT Imaging as a Single Modality for Clinical Staging of Gastric Cancer in Limited Resource Centers: A Retrospective Pilot Study.

Gastric cancer disproportionately impacts populations in resource-limited settings. Within a safety-net network, we assessed the utility of computed tomography (CT) as a single staging modality. We utilized a clinical database of gastric cancer patients treated within the Los Angeles County safety-net hospital system from 2016 to 2023 in conjunction with retrospective imaging review by certified radiologists. We assessed agreement between clinical and pathological staging for patients who underwent curative gastrectomy using the Kappa coefficient. Of 107 patients with available CT imaging, 43.9% (n = 47) were staged with CT as a single modality. Most tumors displayed infiltrating (75%) or diffuse (28%) morphology, 41% displayed adequate gastric distention and regional lymphadenopathy was common (68%). Twenty-nine patients underwent curative gastrectomy. Overall agreement was minimal (κ = 0.29, 95% CI [0.071-0.51], p = 0.022), weak for T3/T4 tumors (κ = 0.50, 95% CI [0.17-0.82], p < 0.01), and weak for Hispanic/Latino patients (κ = 0.47, 95% CI [0.19-0.76], p < 0.01). There was minimal agreement between clinical and pathologic staging when assessing clinical stage by CT imaging alone, suggesting that CT is not adequate as a single modality staging tool. While every effort should be made to obtain multimodal staging, larger studies are warranted to improve CT imaging protocols for staging in resource-limited settings.

Development and Validation of a Computed Tomography-Based Model for Noninvasive Prediction of the T Stage in Gastric Cancer: Multicenter Retrospective Study.

As part of the TNM (tumor-node-metastasis) staging system, T staging based on tumor depth is crucial for developing treatment plans. Previous studies have constructed a deep learning model based on computed tomographic (CT) radiomic signatures to predict the numberoflymphnodemetastases and survival in patients with resected gastric cancer (GC). However, few studies have reported the combination of deep learning and radiomics in predicting T staging in GC. This study aimed to develop a CT-based model for automatic prediction of the T stage of GC via radiomics and deep learning. A total of 771 GC patients from 3 centers were retrospectively enrolled and divided into training, validation, and testing cohorts. Patients with GC were classified into mild (stage T1 and T2), moderate (stage T3), and severe (stage T4) groups. Three predictive models based on the labeled CT images were constructed using the radiomics features (radiomics model), deep features (deep learning model), and a combination of both (hybrid model). The overall classification accuracy of the radiomics model was 64.3% in the internal testing data set. The deep learning model and hybrid model showed better performance than the radiomics model, with overall classification accuracies of 75.7% (P=.04) and 81.4% (P=.001), respectively. On the subtasks of binary classification of tumor severity, the areas under the curve of the radiomics, deep learning, and hybrid models were 0.875, 0.866, and 0.886 in the internal testing data set and 0.820, 0.818, and 0.972 in the external testing data set, respectively, for differentiating mild (stage T1~T2) from nonmild (stage T3~T4) patients, and were 0.815, 0.892, and 0.894 in the internal testing data set and 0.685, 0.808, and 0.897 in the external testing data set, respectively, for differentiating nonsevere (stage T1~T3) from severe (stage T4) patients. The hybrid model integrating radiomics features and deep features showed favorable performance in diagnosing the pathological stage of GC.

The Metabolic Effects and Effectiveness of the Different Reconstruction Methods used in Gastric Cancer Surgery: A Systematic Review and Meta-Analysis.

Gastric Cancer (GC) is the fifth most common cancer worldwide. Early stages of GC began being detected, giving rise to a new concern, Quality of Life. This study aimed to systematically assess the effects of different GC reconstruction techniques on postoperative type 2 diabetes mellitus (T2DM), hypertension (HBP), and body mass index (BMI) reduction rate and to provide an overview of recent research on oncometabolic surgery (OS). We performed a systematic review and meta-analysis by searching three databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We performed a meta-analysis of risk ratios and mean differences to estimate the impact of duodenal bypass, Roux-en-Y reconstruction, and residual stomach on T2DM, HBP, and BMI reduction rate. Heterogeneity was assessed using the I2 statistics. At the end of the follow-up, the duodenal bypass group compared to Billroth I had a significantly higher postoperative remission of T2DM and HBP, with a relative risk (RR) of 1.43 (95% confidence interval (95% CI) [1.27; 1.62]) and 1.3 (95% CI [1.00; 1.69]), respectively. Compared with the Billroth II group, Roux-en-Y reconstruction had significantly greater T2DM remission after gastrectomy (RR = 1.19; 95% CI [1.08; 1.31]), while HBP showed no significant differences. Regarding the improvement of HBP, total gastrectomy was significantly superior to subtotal gastrectomy (95% CI [1.01; 2.64]). A trend towards Roux-en-Y Esophagojejunostomy as the best option for T2DM remission was observed (95% CI [0.98; 2.77]; p = 0.06). Gastrectomy with Roux-en-Y reconstruction appears to be the most effective treatment for T2DM remission. Further research is needed to assess the impact of OS on metabolic diseases.

DIAGNOSTIC ACCURACY OF MULTISPIRAL COMPUTED TOMOGRAPHY IN DETECTING AND STAGING OF ESOPHAGEAL AND GASTRIC CANCER

Background. The sensitivity and specificity of multislice computed tomography is of great importance in the detection of gastric and esophageal cancer, and also expands the possibilities of preoperative staging using computed tomography. Materials and methods. A retrospective study at the A.N. Syzganov National Scientific Center of Surgery from 2022 to 2024, included 121 patients: 48 females (39.6%), 73 males (60.3%), with an average age of 60 years. Sensitivity, specificity were calculated to assess diagnostic accuracy. Esophageal and gastric cancer staging via computed tomography was done using the TNM classification and compared with esophagogastroduodenoscopy, pathohistological examination results. Results. The sensitivity of computed tomography was 96.49%, the specificity was 85.71%. Esophagogastroduodenoscopy showed a sensitivity of 79.75%, specificity of 95.24%. Conclusion. Computed tomography is highly informative, sensitive in detecting esophageal and gastric cancer, with superior diagnostic accuracy compared to esophagogastroduodenoscopy. Given the detection of esophageal and gastric cancer at T2 and T3 stages, along with the presence of distant metastases in some patients, implementing protocols for early diagnosis is advisable.

Plasma cell-free DNA methylome-based liquid biopsy for accurate gastric cancer detection.

Early detection plays a critical role in mitigating mortality rates linked to gastric cancer. However, current clinical screening methods exhibit suboptimal efficacy. Methylation alterations identified from cell-free DNA (cfDNA) present a promising biomarker for early cancer detection. Our study focused on identifying gastric cancer-specific markers from cfDNA methylation to facilitate early detection. We enrolled 150 gastric cancer patients and 100 healthy controls in this study, and undertook genome-wide methylation profiling of cfDNA using cell-free methylated DNA immunoprecipitation and high-throughput sequencing. We identified 21 differentially methylated regions (DMRs) between the gastric tumor and nontumor groups using multiple algorithms. Subsequently, using the 21 DMRs, we developed a gastric cancer detection model by random forest algorithm in the discovery set, and validated the model in an independent set. The model was able to accurately discriminate gastric cancer with a sensitivity and specificity of 93.90% and 95.15% in the discovery set, respectively, and 88.38% and 94.23% in the validation set, respectively. These results underscore the efficacy and accuracy of cfDNA-derived methylation markers in distinguishing early stage gastric cancer. This study highlighted the significance of cfDNA methylation alterations in early gastric cancer detection.

Prognostic value of a modified pathological staging system for gastric cancer based on the number of retrieved lymph nodes and metastatic lymph node ratio.

The prognosis for gastric cancer (GC) remains grim, underscoring the importance of accurate staging and treatment. Given the potential benefits of using lymph node ratio (LNR) for improved prognostication and treatment planning, it is critical to incorporate examined lymph nodes (ELN) count in an integrated GC staging system. Patients data from the Surveillance, Epidemiology, and End Results (SEER) database between 2010 and 2015 was utilized as training set. The Mantel-Cox survival test was used to calculate chi-square values for 40 LNR segments with a 0.025 interval, defining a novel LNR-based N (rN) classification based on the cutoff points. A revised AJCC (rAJCC) staging system was established by replacing the 8th AJCC N staging with a rN classification. The relationship between the ELN count and prognosis or positive lymph node detection was conducted by using multivariable models. The series of the odds ratios and hazard ratios were fitted with a locally weighted scatterplot smoothing (LOWESS) smoother, and the structural break points were determined by Chow test to clarify an optimal minimum ELN count. The integrated GC staging system incorporated both rAJCC system and the ideal ELN count. Discriminatory ability and prognostic homogeneity of the rAJCC and integrated staging system was compared with AJCC staging system in the SEER validation set (2016-2017), the Cancer Genome Atlas Program (TCGA) database, and the Third Affiliated Hospital of Sun Yat-sen University database. The current study found that LNR and ELN count are both significantly associated with the prognosis of GC patients (HR = 0.98, p < 0.001 and HR = 2.51, p < 0.001). Four peaks of the chi-square value were identified as LNR cut-off points at 0.025, 0.175, 0.45 and 0.6 to define a novel rN stage. In comparison to the 8th AJCC staging system, the rAJCC staging system demonstrated significant prognostic advantages and discriminatory ability in the training set (5-Y OS AUC: 71.7 vs. 73.0; AIC: 57,290.7 vs. 57,054.9). The superiority of the rAJCC staging system was confirmed in all validation sets. Using a LOWESS smoother and Chow test, a threshold ELN count of 30 was determined to maximum improvement in the prognosis of node-negative patients without downgrading due to potential metastasis, while also maximizing the detection efficiency of at least one involved lymph node. The integrated staging system, combining the refined rAJCC classification with an optimized ELN count threshold, has demonstrated superior discriminatory performance compared to the standalone rAJCC or the traditional AJCC system. The development of a novel GC staging system, which integrated the LNR-based N classification and the minimum ELN count, has exhibited superior prognostic accuracy, holding promise as a valuable asset in the clinical management of GC. However, it is crucial to recognize the limitations from the retrospective database, which should be addressed in subsequent analyses.

Theory and practice on mesentery margin in vessel-oriented complete mesentery resection of gastric cancer

The concept of mesenteric anatomy has been evolving in cognition. With the continuous development of endoscopic techniques, the submicroscopic structures of many mesenteries have been gradually understood, ultimately confirming the ubiquitous presence of mesenteries in the digestive organs. Based on various domestic and foreign mesenteric anatomical theories and combined with years of clinical practice, we have summarized and proposed a new concept and theory-vascular-guided complete mesenteric resection for gastric cancer. The theoretical basis is that, from the perspective of the embryonic development of the digestive tract, the rotation of the digestive tract and its associated mesentery is always centered on blood vessels. Therefore, the supply vessels and digestive tracts and their associated mesentery are naturally connected. The mesentery is a complex structure that encompasses blood vessels, nerves, and lymphatic tissues. The blood vessels serve as the boundary of the mesentery, ensuring that the lymphatic network that drains the tumor is maximally resected. This article focuses on the complete mesenteric resection margins in gastric cancer surgery, that is, the lateral boundary of the mesentery as the vascular-supplied guided resection boundary and its mesentery, and the base boundary as the mesenteric bed. Using precise vascular guidance to define the extent of mesenteric resection will help accurately define the mesenteric margin during radical resection for different stages of gastric cancer.

HCMV detection in Asian gastric cancer RNA-seq data sets and clinical validation in Indian GC patients reveals the HCMV-GC specific gene signatures.

Gastric cancer (GC) prevalence is very high in the Asian population. Oncogenic viruses play a crucial role in the progression of different types of cancers. Through reanalysis of clinical RNA-seq data sets derived from Asian GC patients, this study identified the presence of human cytomegalovirus (HCMV) in Asian GC tumors, next to the well-studied association of EBV. Clinical recruitment of the Indian GC cohort and screening for HCMV presence identified a 14.28% occurrence, similar to that observed in the bioinformatics analysis. A combinatorial approach of rank-based meta-analysis and ranking of groups based on an expectation-maximization algorithm identified that the upregulated LINC02864 and MAGEA10 correlated with poor survival of GC patients and downregulated tumor suppressor genes enriching for gastric acid secretion pathway to be associated with HCMV-positive GC patients, revealing the progressive role of HCMV infection in GC. Genes that discriminate between different stages of GC were identified through feature selection implemented in a machine-learning approach. LTF and KLK10 expressions were found to be specifically dysregulated by HCMV and can also indicate the GC stages. The results of this study will guide future studies to identify the functional role of these genes in the HCMV-associated GC.IMPORTANCENearly 75% of gastric cancer (GC) cases reported globally are from the Asian population. Most existing public databases, such as TCGA, comprise only a fractional portion of data derived from Asian ancestry. This study identified EBV and human cytomegalovirus (HCMV)'s higher detection in GC patients. The presence and role of EBV associated with GC are well-known, and the observation of HCMV prompted us to validate the findings in a small cohort of 40 Indian GC patients. We observed a 14.28% occurrence of HCMV in the Indian cohort, similar to that observed from next-generation sequencing. A combinatorial approach of rank-based meta-analysis and ranking of groups based on an expectation-maximization algorithm identified that the upregulated LINC02864 and MAGEA10 correlated with poor survival of GC patients and downregulated tumor suppressor genes enriching for gastric acid secretion pathway to be associated with HCMV-positive GC patients, revealing the progressive role of HCMV infection in GC.

Efficacy of neoadjuvant chemotherapy combined with prophylactic intraperitoneal hyperthermic chemotherapy for patients diagnosed with clinical T4 gastric cancer who underwent laparoscopic radical gastrectomy: a retrospective cohort study based on propensity score matching

BackgroundClinical T4 (cT4) stage gastric cancer presents with frequent postoperative recurrence and poor prognosis. This study is to evaluate the oncological efficacy of laparoscopic radical total gastrectomy combined with postoperative prophylactic hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with cT4N + M0 gastric cancer who received neoadjuvant chemotherapy.MethodsWe reviewed the clinicopathological data of 174 patients with clinical T4 gastric cancer who underwent neoadjuvant chemotherapy followed by laparoscopic radical total gastrectomy between June 2017 and December 2021. Among them, 142 were included in the non-HIPEC group, and 32 in the HIPEC group. Patients in both groups were paired based on propensity score in a 2:1 ratio to assess disparities in tumor recurrence and long-term survival.ResultsAfter matching, there were no significant differences in the clinicopathological data between the two groups. The peritoneum (16.1%) and distant organs (10.9%) were the most frequent locations for recurrence. Prior to matching, the recurrence rates were similar at all sites for both groups. Compared with those in the non-HIPEC cohort, the recurrence rates at all sites, the lung, and the peritoneum were notably lower in the HIPEC cohort. Prior to matching, the 3-year overall survival and disease-free survival rates were similar between the two groups; following matching, the HIPEC group exhibited notably greater survival rates than did the non-HIPEC group. The disparities in survival rates between the groups became even more pronounced after conducting a stratified analysis among patients with stage III disease.ConclusionsNeoadjuvant chemotherapy combined with prophylactic HIPEC after laparoscopic radical gastrectomy can effectively reduce the rate of peritoneal metastasis in patients with cT4N + M0 advanced gastric cancer and significantly improve the prognosis of such patients, which is of great clinical value.

Bi-phase CT radiomics nomogram for the preoperative prediction of pylorus lymph node metastasis in non-pyloric gastric cancer patients.

The expansion of function-preserving surgery became possible due to a more profound understanding of gastric cancer (GC), and T1N + or T2N + gastric cancer patients might be potential beneficiaries. However, ways to evaluate the possibility of function-preserving pylorus surgery are still unknown. A total of 288 patients at Renji Hospital and 58 patients at Huadong Hospital, pathologically diagnosed with gastric cancer staging at T1 and T2 with tumors located in the upper two-thirds of the stomach, were retrospectively enrolled from March 2015 to October 2022. Tumor regions of interest (ROIs) were manually delineated on bi-phase CT images, and a nomogram was built and evaluated. The radiomic features distributed differently between positive and negative pLNm groups. Two radiomic signatures (RS1 and RS2) and one clinical signature were constructed. The radiomic signatures exhibited good performance for discriminating pLNm status in the test set. The three signatures were then combined into an integrated nomogram (IN). The IN showed good discrimination of pLNm in the Renji cohort (AUC 0.918) and the Huadong cohort (AUC 0.649). The verification models showed high values. For GC patients with T1 and T2 tumors located in the upper two-thirds of the stomach, a nomogram was successfully built for predicting pylorus lymph node metastasis, which would guide the surgical indication extension of conservative gastrectomies.

Exploring the Influence of T Cell Marker Gene Expression on the Pathobiology and Clinical Prognostic Outcomes in Intestinal-Type Gastric Carcinoma.

Gastric cancer (GC) poses a significant global health challenge. This study is aimed at elucidating the role of the immune system, particularly T cells and their subtypes, in the pathogenesis and progression of intestinal-type gastric carcinoma (GC), and at evaluating the predictive utility of a T cell marker gene-based risk score for overall survival. We performed an extensive analysis using single-cell RNA sequencing data to map the diversity of immune cells and identify specific T cell marker genes within GC. Pseudotime trajectory analysis was employed to observe the expression patterns of tumor-related pathways and transcription factors (TFs) at various disease stages. We developed a risk score using data from The Cancer Genome Atlas (TCGA) as a training set and validated it with the GSE15459 dataset. Our analysis revealed distinct patterns of T cell marker gene expression associated with different stages of GC. The risk score, based on these markers, successfully stratified patients into high-risk and low-risk groups with significantly different overall survival prospects. High-risk patients exhibited poorer survival outcomes compared to low-risk patients (p < 0.05). Additionally, the risk score was capable of identifying patients across a spectrum from chronic atrophic gastritis to early GC. The findings enhance the understanding of the tumor immune microenvironment in GC and propose new immunotherapeutic targets. The T cell marker gene-based risk score offers a potential tool for gastroenterologists to tailor treatment plans more precisely according to the cancer's severity.

Proteome-wide Mendelian randomization and single-cell sequencing analysis identify the association between plasma proteins and gastric cancer.

Targeted therapy is a crucial treatment modality for advanced gastric cancer, with several targets already identified, and the exploration of new targets is important. In this study, our aim was to identify plasma proteins causally associated with gastric cancer to explore novel genetic targets for the disease. Firstly, we utilized protein quantitative trait loci data for 4,907 plasma proteins and genome-wide association study data for gastric cancer to conduct Mendelian randomization (MR) analyses. This was followed by summary-data-based MR analysis on the identified plasma proteins. We then analyzed single-cell sequencing data from the Gene Expression Omnibus database to describe the distribution of genes corresponding to these proteins across different stages and cell types of gastric cancer. MR analysis identified 12 plasma proteins with potential causal associations with gastric cancer, among which motilin (MLN) and THSD1 passed the summary-data-based MR test. These proteins showed no evidence of pleiotropy nor heterogeneity. In single-cell sequencing analysis, EPHB4, KDR, SEMA6B, CDH1, and C1GALT1C1 were found to be enriched in specific cell types within gastric cancer. KDR and LIFR exhibited significant differential expression between gastric cancer and normal tissues. All the 12 genes displayed differential expression across different stages of gastric cancer. Overall, our study identified several plasma proteins with potential causal relationships to gastric cancer. This provides potential candidate targets for gastric cancer research and advances our understanding of the disease's genetic foundations.

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.

New Horizons in the Diagnosis of Gastric Cancer: The Importance of Selected Toll-like Receptors in Immunopathogenesis Depending on the Stage, Clinical Subtype, and Gender of Newly Diagnosed Patients.

Toll-like receptors (TLRs) play a vital role in the innate immune response, recognizing pathogens and initiating the inflammatory response. Research suggests that TLRs may also have a significant impact on the development and progression of cancers, including gastric cancer (GC). Understanding the role of individual TLRs in the immunopathogenesis of gastric cancer may provide new information necessary to develop more effective diagnostic and therapeutic methods. This study aimed to determine the role of selected TLR-2, -3, -4, and -9 in the immunopathogenesis of patients with newly diagnosed and untreated gastric cancer. The study included 60 newly diagnosed, untreated GC patients and 25 healthy volunteers. The research included analyses assessing the percentage of the tested TLRs on T and B lymphocyte subpopulations using multicolor flow cytometry and assessing their concentration in the serum of the examined patients using ELISA tests. The statistical analyses performed included a comparison of patients in individual stages of gastric cancer, an analysis of the most common clinical subtypes of gastric cancer, and a comparative analysis of differences in the gender of recruited patients. Our studies showed different expression levels of TLR-2, -3, -4, and -9 on T and B lymphocyte subpopulations, as well as their different concentrations in patients' serum. Significant differences in the expression of these receptors were observed depending on the stage of gastric cancer and its clinical subtypes. These differences were also visible in the context of patient gender. The results of our studies suggest that TLR-2, -3, -4, and -9 may play an important role in the immunopathogenesis of gastric cancer. The differential expression of these receptors depending on the stage of the disease, clinical subtype, and gender of patients may have potential diagnostic and therapeutic significance. Further research is necessary to understand better the mechanisms of action of TLRs in gastric cancer and to apply this knowledge in clinical practice.

Prognostic value and predictive model of tumor markers in stage I to III gastric cancer patients.

Preoperative serum tumor markers have been widely used in the diagnosis and treatment of gastric cancer patients. However, few studies have evaluated the prognosis of gastric cancer patients by establishing statistical models with multiple serum tumor indicators. To explore the prognostic value and predictive model of tumor markers in stage I and III gastric cancer patients. From October 2018 to April 2020, a total of 1236 patients with stage I to III gastric cancer after surgery were included in our study. The relationship between serum tumor markers and clinical and pathological data were analyzed. We established a statistical model to predict the prognosis of gastric cancer based on the results of COX regression analysis. Overall survival (OS) was also compared across different stages of gastric cancer. The deadline for follow-up was May 31, 2023. A total of 1236 patients were included in our study. Univariate analysis found that age, clinical stage, T and N stage, tumor location, differentiation, Borrmann type, size, and four serum tumor markers were prognostic factors of OS (P < 0.05). It was shown that clinical stage, tumor size, alpha foetoprotein, carcinoembryonic antigen, CA125 and CA19-9 (P < 0.05) were independent prognostic factors for OS. According to the scoring results obtained from the statistical model, we found that patients with high scores had poorer survival time (P < 0.05). Furthermore, in stage I patients, the 3-year OS for scores 0-3 ranged from 96.85%, 95%, 85%, and 80%. In stage II patients, the 3-year OS for scores 0-4 were 88.6%, 76.5%, 90.5%, 65.5% and 60%. For stage III patients, 3-year OS for scores 0-6 were 70.9%, 68.3%, 64.1%, 50.9%, 38.4%, 18.5% and 5.2%. We also analyzed the mean survival of patients with different scores. For stage I patients, the mean OS was 55.980 months. In stage II, the mean OS was 51.550 months. The mean OS for stage III was 39.422 months. Our statistical model can effectively predict the prognosis of gastric cancer patients.