Staging and surgical approaches in gastric cancer: A systematic review

MiR-99a-3p downregulates TRIM21 to promote gastric cancer development

Gastric cancer (GC) stands as one of the most formidable malignancies worldwide. It is well-established that miRNAs play a crucial role in the initiation and progression of various human cancers. Among these, miR-99a-3p has been implicated in the pathogenesis of GC. In the context of our study, we embarked on the comprehensive examination of miR-99a-3p expression in GC cells. Additionally, we sought to establish a correlation between miR-99a-3p expression levels and the overall survival (OS) of GC patients, and our findings hinted at its potential role in predicting an unfavorable prognosis. To further investigate the functional implications of miR-99a-3p in GC, we conducted a series of cell-based experiments after successfully knocking down miR-99a-3p. These investigations uncovered a substantial inhibition of cellular events associated with tumor progression. Moreover, employing TargetScan, we identified Tripartite motif-containing protein 21 (TRIM21) as a putative target with a binding site for miR-99a-3p. Subsequent dual-luciferase reporter gene assay confirmed the direct interaction between miR-99a-3p and TRIM21. Western blot analysis validated the alteration in TRIM21 expression levels, revealing an upregulation upon miR-99a-3p knockdown. Building on these molecular findings, we extended our investigations to human GC tissues, where we observed a downregulation of TRIM21, which, notably, correlated with shorter overall survival. Lastly, to further solidify our conclusions, we conducted a series of in vitro and in vivo rescue experiments, collectively suggesting that miR-99a-3p promoted the progression of GC cells through the downregulation of TRIM21. In summary, our study comprehensively explored the role of miR-99a-3p in GC, revealing its association with unfavorable patient outcomes, functional implications in tumor progression, and a direct regulatory relationship with TRIM21. These findings collectively underscore the significance of miR-99a-3p in the pathogenesis of GC and present a potential therapeutic avenue for further investigation.

Targeting TRAF6/IRF3 axis to inhibit NF-κB-p65 nuclear translocation enhances the chemosensitivity of 5-FU and reverses the proliferation of gastric cancer

Chemoresistance poses a significant clinical challenge in the treatment of gastric cancer (GC), while its underlying molecular mechanisms are still not fully understood. Post-translational protein modification and abnormal activation of nuclear factor-kappa B (NF-κB) are critical regulators of tumor chemoresistance. This study investigates the role of TNF receptors-associated factors 6 (TRAF6) in 5-Fluorouracil (5-FU) resistant GC. Utilizing short hairpin RNA (shRNA) to suppress TRAF6 expression in 5-FU resistant GC cells across both in vivo and in vitro models, we observed a marked reduction in cell proliferation and tumor growth. Low expression of TRAF6 inhibited nuclear translocation of NF-κB-p65, which was achieved by promoting the expression of Interferon regulatory factor 3 (IRF3). Importantly, TRAF6, an E3 ubiquitin ligase, bound to the IRF3-Δ (SR + IAD) (1-190aa) domain, inducing Lys70 ubiquitination of IRF3 to regulate its protein stability, with ubiquitin K48 residue playing a crucial role in this process. In conclusion, our study reveals the mechanism by which the TRAF6/IRF3 axis decreases GC's cells sensitivity to 5-FU by promoting nuclear translocation of NF-κB-p65, offering valuable insights into overcoming chemoresistance in GC.

Combined detection of serum EFNA1 and MMP13 as diagnostic biomarker for gastric cancer

We previously identified that serum EFNA1 and MMP13 were potential biomarker for early detection of esophageal squamous cell carcinoma. In this study, our aim is to explore the diagnostic value of serum EFNA1 and MMP13 for gastric cancer. We used enzyme-linked immunosorbent assay (ELISA) to detect the expression levels of serum EFNA1 and MMP13 in 210 GCs and 223 normal controls. The diagnostic value of EFNA1 and MMP13 was evaluated in an independent cohorts of GC patients and normal controls (n = 238 and 195, respectively). Receiver operating characteristics were used to calculate diagnostic accuracy. In training and validation cohorts, serum EFNA1 and MMP13 levels in the GC groups were significantly higher than those in the normal controls (P < 0.001). The area under the curve (AUC) of the combined detection of serum EFNA1 and MMP13 for GC was improved (0.794), compared with single biomarker used. Similar results were observed in the validation cohort. Importantly, the combined measurement of serum EFNA1 and MMP13 to detect early-stage GC also had acceptable diagnostic accuracy in training and validation cohort. Combined detection of serum EFNA1 and MMP13 could help identify early-stage GC, suggesting that it may be a promising tool for the early detection of GC.

HCA-DAN: hierarchical class-aware domain adaptive network for gastric tumor segmentation in 3D CT images

BACKGROUND

Accurate segmentation of gastric tumors from CT scans provides useful image information for guiding the diagnosis and treatment of gastric cancer. However, automated gastric tumor segmentation from 3D CT images faces several challenges. The large variation of anisotropic spatial resolution limits the ability of 3D convolutional neural networks (CNNs) to learn features from different views. The background texture of gastric tumor is complex, and its size, shape and intensity distribution are highly variable, which makes it more difficult for deep learning methods to capture the boundary. In particular, while multi-center datasets increase sample size and representation ability, they suffer from inter-center heterogeneity.

METHODS

In this study, we propose a new cross-center 3D tumor segmentation method named Hierarchical Class-Aware Domain Adaptive Network (HCA-DAN), which includes a new 3D neural network that efficiently bridges an Anisotropic neural network and a Transformer (AsTr) for extracting multi-scale context features from the CT images with anisotropic resolution, and a hierarchical class-aware domain alignment (HCADA) module for adaptively aligning multi-scale context features across two domains by integrating a class attention map with class-specific information. We evaluate the proposed method on an in-house CT image dataset collected from four medical centers and validate its segmentation performance in both in-center and cross-center test scenarios.

RESULTS

Our baseline segmentation network (i.e., AsTr) achieves best results compared to other 3D segmentation models, with a mean dice similarity coefficient (DSC) of 59.26%, 55.97%, 48.83% and 67.28% in four in-center test tasks, and with a DSC of 56.42%, 55.94%, 46.54% and 60.62% in four cross-center test tasks. In addition, the proposed cross-center segmentation network (i.e., HCA-DAN) obtains excellent results compared to other unsupervised domain adaptation methods, with a DSC of 58.36%, 56.72%, 49.25%, and 62.20% in four cross-center test tasks.

CONCLUSIONS

Comprehensive experimental results demonstrate that the proposed method outperforms compared methods on this multi-center database and is promising for routine clinical workflows.

Preoperative 6-minute walk distance is associated with postoperative complications in patients undergoing laparoscopic gastrointestinal cancer surgery

OBJECTIVE

The 6-min walk test (6MWT) is a simple and valid method to evaluate cardiopulmonary function. We performed this prospective study in patients undergoing laparoscopic gastrointestinal cancer surgery to explore the association between preoperative 6MWT performance and overall postoperative complications.

METHODS

This study was registered at clinicaltrials.gov (NCT03711526). The study consecutively enrolled patients receiving laparoscopic gastrointestinal cancer surgery in our institution. All patients performed the 6MWT upon recruitment and received 30 days of postoperative follow-up. The primary outcome was overall complications, defined by ≥ grade I Clavien-Dindo (CD) classification (2004) complications. Multivariable logistic regression was used to test the association of 6-min walk distance (6MWD) with the outcome.

RESULTS

A total of 184 patients were included in the final analyses. In the 37 (20.1 %) patients with overall complications, the mean (standard deviation) preoperative 6MWD was 469.1 (86.8) m. In patients with no complications, the 6MWD was 502.6 (90.2) m. The mean difference was 33.5 m (95 % confidence interval, 1.3, 65.7; P = 0.042). A longer preoperative 6MWD was associated with a lower odds of developing postoperative complications (odds ratio, 0.994 per meter increase; 95 % confidence interval, 0.989, 0.999; p = 0.023).

CONCLUSION

This study indicated an association between the preoperative 6MWD and postoperative complications in patients undergoing laparoscopic gastrointestinal cancer surgery.

Gastric cancer metastasis-related NT5DC2 indicates unfavorable prognosis of patients

PURPOSE

Approximately 80 to 90% of patients with gastric cancer (GC) eventually develop into metastatic GC nowadays,because GC is difficult to be diagnosed at an early stage. GC patients with metastases typically have a poor prognosis. It is necessary to explore a potential prognostic marker in metastatic GC.

METHODS

All GC data were obtained from The Cancer Genome Atlas and Gene Expression Omnibus databases. The metastasis-related candidate gene and its role in GC were analyzed by comprehensive analysis.

RESULTS

Totally 1049 metastasis-related genes were identified in GC. Univariate Cox regression analysis screened the top 10 genes (PDHX, SLC43A1, CSAG2, NT5DC2, CSAG1, FMN1, MED1, HIVEP2, FNDC3A, and PPP1R2) that were closely correlated with prognosis of GC patients. Among which, NT5DC2 was screened as the target gene for subsequent study. The NT5DC2 expression were increased in primary GC and metastatic GC samples. Moreover, GC patients with high NT5DC2 expression exhibited shorter overall survival and post progression survival, and the NT5DC2 was metastatic GC patients' independent prognostic factor. Totally 29 pathways were activated in metastatic GC samples with high NT5DC2 expression. Four immune cells' infiltration were significantly different between NT5DC2 high and low expressed metastatic GC patients. NT5DC2 showed significantly negative correlations with 6 types of immune cells' critical marker genes and 5 types of immune cell infiltration. The 10 immune checkpoint expressions were decreased in high NTDC2 expression metastatic GC patients.

CONCLUSIONS

NT5DC2 plays a prognostic role in metastatic GC. GC patients with high NT5DC2 expression indicates unfavorable prognosis.

The minimum number of examined lymph nodes was 24 for optimal survival of pathological T2-4 gastric cancer: a multi-center, hospital-based study covering 20 years of data

INTRODUCTION

The current National Comprehensive Cancer Network (NCCN) guidelines recommend that at least 16 lymph nodes should be examined for gastric cancer patients to reduce staging migration. However, there is still debate regarding the optimal management of examined lymph nodes (ELNs) for gastric cancer patients. In this study, we aimed to develop and test the minimum number of ELNs that should be retrieved during gastrectomy for optimal survival in patients with gastric cancer.

METHODS

We used the restricted cubic spline (RCS) to identify the optimal threshold of ELNs that should be retrieved during gastrectomy based on the China National Cancer Center Gastric Cancer (NCCGC) database. Northwest cohort, which sourced from the highest gastric cancer incidence areas in China, was used to verify the optimal cutoff value. Survival analysis was performed via Kaplan-Meier estimates and Cox proportional hazards models.

RESULTS

In this study, 12,670 gastrectomy patients were included in the NCCGC cohort and 4941 patients in the Northwest cohort. During 1999-2019, the average number of ELNs increased from 17.88 to 34.45 nodes in the NCCGC cohort, while the number of positive lymph nodes remained stable (5-6 nodes). The RCS model showed a U-curved association between ELNs and the risk of all-cause mortality, and the optimal threshold of ELNs was 24 [Hazard ratio (HR) = 1.00]. The ELN ≥ 24 group had a better overall survival (OS) than the ELN < 24 group clearly (P = 0.003), however, with respect to the threshold of 16 ELNs, there was no significantly difference between the two groups (P = 0.101). In the multivariate analysis, ELN ≥ 24 group was associated with improved survival outcomes in total gastrectomy patients [HR = 0.787, 95% confidence interval (CI): 0.711-0.870, P < 0.001], as well as the subgroup analysis of T2 patients (HR = 0.621, 95%CI: 0.399-0.966, P = 0.035), T3 patients (HR = 0.787, 95%CI: 0.659-0.940, P = 0.008) and T4 patients (HR = 0.775, 95%CI: 0.675-0.888, P < 0.001).

CONCLUSION

In conclusion, the minimum number of ELNs for optimal survival of gastric cancer with pathological T2-4 was 24.

Preoperative low handgrip strength (HGS) with HGS asymmetry is associated with adverse outcomes among older adults with gastric cancer

INTRODUCTION

This study aimed to explore the associations of low hand grip strength (HGS), HGS asymmetry, their combinations, and frailty on hospital readmissions, total complications, and prolonged length of stay (PLOS) among older adults with gastric cancer.

MATERIALS AND METHODS

This study included 342 patients with gastric cancer aged ≥60 years who were scheduled to undergo radical surgery. The Tilburg Frailty Indicator (TFI) was used to collect information on frailty. HGS was measured twice for each hand using an electronic handgrip dynamometer. The highest HGS readings on each hand were used for calculating the HGS asymmetry ratio: non-dominant HGS (kg)/dominant HGS (kg). The Fine and Gray proportional subdistribution hazard model and the logistic regression model were used for the analyses, with covariates adjusted.

RESULTS

Low HGS (subdistribution hazard ratios [SHR] = 2.10, 95% confidence interval [CI] = 1.05-3.93, P = 0.036) and low HGS with HGS asymmetry (SHR = 3.95, 95% CI = 1.50-10.36, P = 0.005) were significantly associated with hospital readmissions. Frailty was associated with total complications (odds ratio [OR] = 2.87, 95% CI = 1.61-5.13, P < 0.001) and PLOS (OR = 1.98, 95% CI = 1.19-3.29, P < 0.001). Low HGS, HGS asymmetry, and their combinations were not significantly associated with total complications and PLOS.

DISCUSSION

Preoperative low HGS and low HGS with HGS asymmetry were associated with hospital readmissions, while frailty was associated with total complications and PLOS among older adults with gastric cancer. In the future, more rigorously designed studies are needed to verify our results further to improve preoperative clinical assessment and frailty evaluation among older adults with gastric cancer.

Interleukin-33 as a Potential Therapeutic Target in Gastric Cancer Patients: Current Insights

Gastric cancer is a significant global health problem as it is the fifth most prevalent cancer worldwide and the fourth leading cause of cancer-related mortality. While cytotoxic chemotherapy remains the primary treatment for advanced GC, response rates are limited. Recent progresses, focused on molecular signalling within gastric cancer, have ignited new hope for potential therapeutic targets that may improve survival and/or reduce the toxic effects of traditional therapies. Carcinomas are generally initiated when critical regulatory genes get mutated, but the progression to malignancy is usually supported by the non-neoplastic cells that create a conducive environment for transformation and progression to occur. Interleukin 33 (IL-33) functions as a dual activity cytokine as it is also a nuclear factor. IL-33 is usually present in the nuclei of the cells. Upon tissue damage, it is released into the extracellular space and binds to its receptor, suppression of tumorigenicity 2 (ST2) L, which is expressed on the membranes of the target cells. IL-33 signalling activates the T Helper 2 (Th2) immune response among other responses. Although the studies on the role of IL-33 in gastric cancer are still in the early stages, they have revealed potentially important (though sometimes conflicting) functions or roles in cancer development and progression. The pro-tumorigenic roles include induction and the recruitment of tumor-associated immune cells, promoting metaplasia progression, and inducing stem cell like and EMT properties in gastric cancer cells. Therapeutic interventions to disrupt these functions may provide a unique strategy for gastric cancer prevention and treatment. This review aims to provide a summary of the role of IL-33 in GC, state its multiple functions in relation to GC, and show potential avenues for promising therapeutic investigation.

Zinc Finger Proteins in the War on Gastric Cancer: Molecular Mechanism and Clinical Potential

According to the 2020 global cancer data released by the World Cancer Research Fund (WCRF) International, gastric cancer (GC) is the fifth most common cancer worldwide, with yearly increasing incidence and the second-highest fatality rate in malignancies. Despite the contemporary ambiguous molecular mechanisms in GC pathogenesis, numerous in-depth studies have demonstrated that zinc finger proteins (ZFPs) are essential for the development and progression of GC. ZFPs are a class of transcription factors with finger-like domains that bind to Zn²⁺ extensively and participate in gene replication, cell differentiation and tumor development. In this review, we briefly outline the roles, molecular mechanisms and the latest advances in ZFPs in GC, including eight principal aspects, such as cell proliferation, epithelial-mesenchymal transition (EMT), invasion and metastasis, inflammation and immune infiltration, apoptosis, cell cycle, DNA methylation, cancer stem cells (CSCs) and drug resistance. Intriguingly, the myeloid zinc finger 1 (MZF1) possesses reversely dual roles in GC by promoting tumor proliferation or impeding cancer progression via apoptosis. Therefore, a thorough understanding of the molecular mechanism of ZFPs on GC progression will pave the solid way for screening the potentially effective diagnostic indicators, prognostic biomarkers and therapeutic targets of GC.

Pattern of Distribution of Lymph Node Metastases in Individual Stations in Middle and Lower Gastric Carcinoma

(1) Background: Lymph node (LN) dissection is the cornerstone of curative treatment of GC. The pattern of distribution of LN metastases is closely related to several factors. The aim of this study is to evaluate the factors determining the distribution of nodal metastases in a population of N+ distal GC patients undergoing gastrectomy and D2 lymphadenectomy. (2) Methods: The medical charts of 162 N+ GC patients who underwent surgical resection over a 15-year period were retrospectively analyzed. Clinical, pathological and anatomical characteristics were evaluated to identify the factors affecting the patterns and prevalence of metastases in individual LN stations. (3) Results: LN metastasis is correlated with the depth of the tumor and to diffuse-type tumors. A higher number of metastatic nodes was documented in patients with middle-third tumors (8.2 ± 7.3 vs. 4.5 ± 5.0 in lower-third tumors, p = 0.0001) and in patients with tumors located on the lesser curve. Station 4 showed the highest rate of metastases (53.1%). Concerning stations 7 to 12, station 8 showed the highest metastasis rate (28.4%). Metastases at stations 1, 2, 4 and 7 to 11 were dominant in middle-third cancer, whereas stations 5 and 6 were dominant in lower-third cancers. Station 4, 5, 6, 10 and 11 metastases were dominant when the cancer was located on the greater curve, whereas stations 1, 2, 7, 8 and 12 were dominant in lesser-curve cancers. (4) Conclusions: The study documented that in patients with distal GC, the distribution of nodal metastases at individual stations is closely related to primary tumor location.

Genomic instability-related twelve-microRNA signatures for predicting the prognosis of gastric cancer

Gastric cancer (GC) ranks fifth among all malignant tumors globally, especially in East Asia, and has attracted extensive attention and research. MicroRNA (miRNA) modulation during genomic instability (GI) may be associated with the development and metastasis of malignant tumors. We aimed to identify GI-related miRNA signatures for the prediction of GC prognosis. We constructed a GI-related miRNA signature (GIMiSig) scheme based on The Cancer Genome Atlas (TCGA) training set (n = 389), which was later verified based on the TCGA test set (n = 194). GI-related miRNAs were identified by analyzing somatic mutation profiles and miRNA expression. A GI-related miRNA-gene co-expression network was also constructed. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were analyzed to reveal possible biological pathways associated with GI-related miRNAs. The correlation of the GIMiSig with clinical factors of the TCGA dataset was analyzed. MiRNA mimics and inhibitors were used to evaluate the biological functions of miR-100-5p and miR-145-3p in GC cell lines AGS and MKN-45. This study identified a GI-related 12-miRNA signature for the prediction of GC prognosis. GIMiSig scores, similar to tumor stages, showed significant correlations with overall survival (OS, p < 0.05). GIMiSig showed high accuracy in predicting GC prognosis. MiR-100-5p and miR-145-3p promoted cell growth, invasion, and migration but inhibited apoptosis in GC cells. We report a reliable GI-related 12-miRNA signature for predicting GC prognosis. Furthermore, miR-100-5p and miR-145-3p may promote GC cell growth, invasion, and migration.

Ponciri Fructus Immatarus Sensitizes the Apoptotic Effect of Hyperthermia Treatment in AGS Gastric Cancer Cells through ROS-Dependent HSP Suppression

Gastric cancer has been associated with a high incidence and mortality, accompanied by a poor prognosis. Given the limited therapeutic options to treat gastric cancer, alternative treatments need to be urgently developed. Hyperthermia therapy is a potentially effective and safe treatment option for cancer; however, certain limitations need to be addressed. We applied 43 °C hyperthermia to AGS gastric cancer cells combined with Ponciri Fructus Immaturus (PF) to establish their synergistic effects. Co-treatment with PF and hyperthermia synergistically suppressed AGS cell proliferation by inducing extrinsic and intrinsic apoptotic pathways. Additionally, PF and hyperthermia suppressed factors related to metastasis. Cell cycle arrest was determined by flow cytometry, revealing that co-treatment induced arrest at the G2/M phase. As reactive oxygen species (ROS) are critical in hyperthermia therapy, we next examined changes in ROS generation. Co-treatment with PF and hyperthermia increased ROS levels, and apoptotic induction mediated by this combination was partially dependent on ROS generation. Furthermore, heat shock factor 1 and heat shock proteins (HSPs) were notably suppressed following co-treatment with PF and hyperthermia. The HSP-regulating effect was also dependent on ROS generation. Overall, these findings suggest that co-treatment with PF and hyperthermia could afford a promising anticancer therapy for gastric cancer.

Effects of individualized dietary counseling on nutritional status and quality of life in post-discharge patients after surgery for gastric cancer: A randomized clinical trial

Background

Currently, the supporting evidence for dietary counseling is insufficient. The aim of this study is to evaluate the impact of individualized dietary counseling on nutritional outcomes and quality of life (QOL) in patients undergoing surgery for gastric cancer.

Methods

This study was a prospective, single-center, randomized controlled trial. The patients after surgery for gastric cancer were randomly assigned (1:1) to the intervention group and the control group. In the intervention group, patients receive individualized dietary counseling based on individual calorie needs and symptom assessment at 24 h before discharge, 14, 21, 30, and 60 days postoperatively. Patients in the control group received routine dietary counseling. The primary endpoint was body mass index (BMI) loss at 30, 60, and 90 days after surgery; the secondary endpoints were calorie and protein intake at 30 and 60 days after surgery, blood parameters, the 90-day readmission rate, and QOL at 90 days after surgery.

Results

One hundred thirty patients were enrolled; 67 patients were assigned to the intervention group and 63 patients to the control group. Compared with the control group, patients in the intervention group were significantly less BMI loss at 30 days (-0.84 ± 0.65 vs. -1.29 ± 0.83), 60 days (-1.29 ± 0.92 vs. -1.77 ± 1.13), and 90 days (-1.37 ± 1.05 vs. -1.92 ± 1.66) after surgery (all P< 0.05). Subgroups analysis by surgery type showed that the intervention could significantly reduce BMI loss in patients undergoing total and proximal gastrectomy at 30 days (-0.75 ± 0.47 vs. -1.55 ± 1.10), 60 days (-1.59 ± 1.02 vs. -2.55 ± 1.16), and 90 days (-1.44 ± 1.19 vs. -3.26 ± 1.46) after surgery (all P< 0.05). At 60 days after surgery, calorie goals were reached in 35 patients (77.8%) in the intervention group and 14 patients (40.0%) in the control group (P = 0.001), and protein goals were reached in 40 patients (88.9%) in the intervention group and 17 patients (48.6%) in the control group (P< 0.001). Regarding the QOL at 90 days after surgery, the patients in the intervention group had a significantly lower level of fatigue, shortness of breath and stomach pain, better physical function, and cognitive function (P< 0.05).

Conclusions

Post-discharge individualized dietary counseling is an effective intervention to reduce post-gastrectomy patient weight loss and to elevate calorie intake, protein intake, and QOL.

Totally laparoscopic total gastrectomy with Uncut Roux-en-Y for gastric cancer may improve prognosis: A propensity score matching comparative study

Background

Laparoscopic total gastrectomy (LTG) with Roux-en-Y (RY) is often accompanied by a series of complications. Uncut RY (URY) can effectively reduce Roux stasis syndrome (RSS) in laparoscopic distal gastrectomy. To determine whether totally LTG (TLTG) with URY for gastric cancer (GC) can replace RY in short-term and long-term prognosis.

Methods

This comparative retrospective study selected GC patients from 2016 to 2022. The patients were divided into URY group and RY group. Cox multivariate proportional hazard regression analysis was used to explore the independent prognostic factors. Propensity score matching (PSM) was used to reduce bias.

Results

A total of 100 GC patients met the inclusion criteria. Compared to RY group, URY group showed significant advantages in operation time and length of hospital stay. In addition, URY group can significantly reduce short-term and long-term complications, especially RSS. The 1-, 3- and 5-year progression free survival (PFS) of URY group and RY group were 90.4% vs. 67.8% (P=0.005), 76.6% vs. 52.6% (P=0.009) and 76.6% vs. 32.8% (P<0.001), respectively. After PSM, the advantage of URY in PFS was verified again, while there was no significant difference in overall survival (OS) between the two groups. Cox multivariate analysis suggested that lower RSS was associated with better PFS.

Conclusions

TLTG with URY for GC helps control disease progression, speed up recovery and reduce short and long-term complications, especially RSS.

Signaling pathways and therapeutic interventions in gastric cancer

Gastric cancer (GC) ranks fifth in global cancer diagnosis and fourth in cancer-related death. Despite tremendous progress in diagnosis and therapeutic strategies and significant improvements in patient survival, the low malignancy stage is relatively asymptomatic and many GC cases are diagnosed at advanced stages, which leads to unsatisfactory prognosis and high recurrence rates. With the recent advances in genome analysis, biomarkers have been identified that have clinical importance for GC diagnosis, treatment, and prognosis. Modern molecular classifications have uncovered the vital roles that signaling pathways, including EGFR/HER2, p53, PI3K, immune checkpoint pathways, and cell adhesion signaling molecules, play in GC tumorigenesis, progression, metastasis, and therapeutic responsiveness. These biomarkers and molecular classifications open the way for more precise diagnoses and treatments for GC patients. Nevertheless, the relative significance, temporal activation, interaction with GC risk factors, and crosstalk between these signaling pathways in GC are not well understood. Here, we review the regulatory roles of signaling pathways in GC potential biomarkers, and therapeutic targets with an emphasis on recent discoveries. Current therapies, including signaling-based and immunotherapies exploited in the past decade, and the development of treatment for GC, particularly the challenges in developing precision medications, are discussed. These advances provide a direction for the integration of clinical, molecular, and genomic profiles to improve GC diagnosis and treatments.

[ICG lymph node mapping in cancer surgery of the upper gastrointestinal tract]

The importance of the assessment of the N‑status in gastric carcinoma, tumors of the gastroesophageal junction and esophageal cancer is undisputed; however, there is currently no internationally validated method for lymph node mapping in esophageal and gastric cancer. Near-infrared fluorescence imaging (NIR) is an innovative technique from the field of vibrational spectroscopy, which in combination with the fluorescent dye indocyanine green (ICG) enables intraoperative real-time visualization of anatomical structures. The ICG currently has four fields of application in oncological surgery: intraoperative real-time angiography for visualization of perfusion, lymphography for visualization of lymphatic vessels, visualization of solid tumors, and (sentinel) lymph node mapping. For imaging of the lymph drainage area and therefore the consecutive lymph nodes, peritumoral injection of ICG must be performed. Several studies have demonstrated the feasibility of peritumoral injection of ICG administered 15 min to 3 days preoperatively with subsequent intraoperative visualization of the lymph nodes. So far prospective randomized studies on the validation of the method are still lacking. In contrast, the use of ICG for lymph node mapping and visualization of sentinel lymph nodes in gastric cancer has been performed in large cohorts as well as in prospective randomized settings. Up to now, multicenter studies for ICG-guided lymph node mapping during oncological surgery of the upper gastrointestinal tract are lacking. Artificial intelligence methods can help to evaluate these techniques in an automated manner in the future as well as to support intraoperative decision making and therefore to improve the quality of oncological surgery.

Platelet-Derived Growth Factors Affect Clinical Features and Prognosis of Gastric Cancer

Purpose. To investigate the association of platelet-derived growth factors (PDGFs), clinicopathological features, and prognosis in gastric cancer patients. Methods. Tumor specimens of 180 individuals with gastric cancer treated between 2016 and 2020 were collected. Immunohistochemical staining and Western blot (WB) were used to detect the expression of PDGF-B and PDGF-D. The relationship between the expression of PDGF-B and PDGF-D and relapse-free subsistence (RFS) time was assessed using Kaplan–Meier curves. Univariate and multivariate Cox proportional hazards regression models were used to evaluate the relationship between the expression of PDGF-B and PDGF-D and the prognosis and clinicopathological features in gastric cancer patients. Results. High expression of PDGF-B and PDGF-D was detected in 108 (60%) and 137 (76%) tumor specimens, respectively. The expressions of PDGF-B and PDGF-D were independent predictive indicators in multivariate analysis when compared to tumor depth, tumor stage, lymph node metastasis, and RFS ( $P<0.01$ ). Conclusion. The high expression of PDGF-B and PDGF-D in gastric cancer tissues is associated with poor prognosis and poor survival rate of the patients. The expression of PDGF-B and PDGF-D can be used as important indicators to evaluate the biological behavior and prognosis of gastric cancer.

Novel Necroptosis-Related Gene Signature for Predicting Early Diagnosis and Prognosis and Immunotherapy of Gastric Cancer

Simple Summary

Necroptosis plays an important role in the occurrence and development of many cancers. MLKL is an important component of necroptosis, and has been proved to be closely related to the prognosis of gastric cancer (GC). We determined an early diagnosis (FAP, CCT6A) and prognosis risk score (ZFP36, TP53I3, FAP, CCT6A) model of necroptosis-related genes (NRGs) in GC. Two models, respectively, can effectively predict the occurrence of GC and the prognosis of GC patients. The association between the prognostic risk score and the response to immunotherapy and immune checkpoint inhibitors (ICIs) was also analyzed. FAP was also identified as the core gene in the two models, and the relationship between its expression in GC and ICIs was analyzed. This discovery is the first time that NRGs were combined with immunotherapy for GC and provides a new target for immunotherapy for GC and a more accurate treatment scheme for GC patients.

Abstract

Necroptosis is a kind of programmed necrosis, which is different from apoptosis and pyroptosis. Its molecular mechanism has been described in inflammatory diseases. Gastric cancer (GC) is one of the most common malignancies worldwide with the third highest mortality. However, the role of necroptosis in the occurrence and progression of GC remains largely unexplored. Therefore, we investigated necroptosis-related genes (NRGs) by analyzing public transcriptomic data from GC samples. Our results indicate that 83 of 740 NRGs are dysregulated in GC tissues. Next, we identified necroptosis-associated early diagnosis and prognostic gene signatures for GC using machine learning. 2-NRGs (CCT6A and FAP) and 4-NRGs (ZFP36, TP53I3, FAP, and CCT6A), respectively, can effectively assess the risk of early GC (AUC = 0.943) and the prognosis of GC patients (AUC = 0.866). Through in-depth analysis, we were pleasantly surprised to find that there was a significant correlation between the 4-NRGs and GC immunotherapy effect and immune checkpoint inhibitors (ICIs), which could be used for the evaluation of immunosuppressants. Finally, we identified the core gene FAP, and established the relationship between FAP and ICIs in GC. These findings could provide a new target for immunotherapy for GC and a more effective treatment scheme for GC patients.

Expression profiles of m6A RNA methylation regulators, PD-L1 and immune infiltrates in gastric cancer

Gastric cancer is the fourth most frequent cancer and has a high death rate. Immunotherapy represented by PD-1 has brought hope for the treatment of advanced gastric cancer. Methylation of the m6A genes is linked to the onset and progression of numerous cancers, but there are few studies on gastric cancer. The main purpose of this study aims to analyze the relationship between m6A RNA methylation regulators, PD-L1, prognosis and tumor immune microenvironment (TIME) in gastric cancer. The Cancer Genome Atlas (TCGA) and Genotype Tissue Expression (GTEx) databases were used to acquire transcriptomic data and clinical information from gastric cancer patients. The changes in m6A regulator expression levels in gastric cancer tissues and normal tissues were studied. Consensus clustering analysis was used to separate gastric cancer samples into two categories. We employed Least Absolute Shrinkage, Selection Operator (LASSO) Cox regression analysis, Gene Set Enrichment Analysis (GSEA), and cBioPortal to analyze the m6A regulators, PD-L1 and TIME in gastric cancer. In gastric cancer tissues, the majority of m6A regulatory factors are considerably overexpressed. Two gastric cancer subgroups (Cluster1/2) based on consensus clustering of 21 m6A regulators. PD-L1 and PD-1 expression levels were significantly higher in gastric cancer tissues, and they were significantly linked with METTL3, WTAP, HNRNPD, ZC3H7B, METTL14, FTO, PCIF1, HNRNPC, YTHDF1 and YTDHF2. Cluster1 showed a large increase in resting memory CD4⁺ T cells, regulatory T cells, naïve B cells, active NK cells, and resting Mast cells. Cluster1 and Cluster2 were shown to be involved in numerous critical signaling pathways, including base excision repair, cell cycle, nucleotide excision repair, RNA degradation, and spliceosome pathways. Gastric cancer RiskScores based on prognostic factors have been found as independent prognostic indicators. The amount of tumor-infiltrating immune cells is dynamically affected by changes in the copy number of m6A methylation regulators associated with TIME.

Abdominal Computed Tomography Enhanced Image Features under an Automatic Segmentation Algorithm in Identification of Gastric Cancer and Gastric Lymphoma

To analyze the application value of CT-enhanced scanning based on artificial intelligence algorithm in the diagnosis of gastric cancer and gastric lymphoma, the CT images of 80 patients with Borrmann type IV gastric cancer or primary gastric lymphoma diagnosed by endoscopic pathology were retrospectively collected. Meanwhile, a lymph node recognition algorithm based on OTSU threshold segmentation was proposed for CT image processing. The results showed that the missed diagnosis rate of suspected lymph nodes and the missed lymph node detection rate of this algorithm were substantially lower than those of other algorithms (P < 0.05). The probability of gastric wall motility disappearance, perigastric fat infiltration, and type A enhancement pattern in the Borrmann type IV gastric cancer group was higher than that in the gastric lymphoma group, with remarkable differences (P < 0.05). There was no remarkable difference between the Borrmann type IV gastric cancer group and the gastric lymphoma group in the probability of swollen lymph nodes under the renal hilum (P > 0.05). In addition, 5the sensitivity (83.17%), specificity (95.52%), and accuracy (93.08%) of the combined detection of the three CT signs (stomach wall motility, perigastric fat infiltration, and enhancement mode) were substantially improved compared with those of a single sign (P < 0.05). To sum up, the lymph node recognition algorithm based on OTSU threshold segmentation had better performance in detecting gastric lymph nodes than traditional algorithms. The CT image characteristics of gastric wall motility, perigastric fat infiltration, and enhancement pattern based on artificial intelligence algorithms were effective indicators for distinguishing gastric cancer and gastric lymphoma.

Ursolic acid silences CYP19A1/aromatase to suppress gastric cancer growth

INTRODUCTION

Gastric cancer (GCa) is a malignancy with few effective treatments. Ursolic acid (UA), a bioactive triterpenoid enriched in Hedyotis diffusa Willd, known to suppress GCa without identified target. CYP19A1 (cytochrome P450 family 19A1; also known as aromatase, Ar) was correlated to GCa prognosis. Relatedly, Ar silencers, which halt the expression of Ar exhibited anti-GCa effects in experimental models, are currently being investigated.

METHOD

The docking simulation score of UA was compared with Ar inhibitors, e.g., letrozole, exemestane, in Ar protein crystallization. Hedyotis diffusa Willd ethanol extract, UA, or 5-fluracil were applied onto AGS, SC-M1, MKN45 GCa cells for cancer inhibition tests. Immunoblot for measuring gene expressions upon drug treatments, or gene knockdown/overexpression. Treatments were also applied in a MKN45 implantation tumor model. A web-based GCa cohort for Ar expression association with prognosis was performed.

RESULT

The ethanol extracts of Hedyotis diffusa Willd, enrich with UA, exhibited cytotoxic activity against GCa cells. Molecular docking simulations with the 3D Ar structure revealed an excellent fitting score for UA. UA increase cytotoxic, and suppressed colony, in addition to its Ar silencing capacity. Moreover, UA synergistically facilitated 5-FU, (a standard GCa treatment) regimen in vitro. Consistent with those results, adding estradiol did not reverse the cancer-suppressing effects of UA, which confirmed UA acts as an Ar silencer. Furthermore, UA exhibited tumor-suppressing index (TSI) score of 90% over a 6-week treatment term when used for single dosing in xenograft tumor model. In the clinical setting, Ar expression was found to be higher in GCa tumors than normal parental tissue from the TCGA (The Cancer Genome Atlas) cohort, while high Ar expression associated with poor prognosis. Together, the results indicate UA could be used to treat GCa by silencing Ar expression in GCa. Hedyotis diffusa Willd ethanol extract could be an functional food supplements.

Ferroptosis and its Role in Gastric Cancer

Gastric cancer (GC) is the fifth most common cancer and the third leading cause of cancer-related deaths worldwide. Currently, surgery is the treatment of choice for GC. However, the associated expenses and post-surgical pain impose a huge burden on these patients. Furthermore, disease recurrence is also very common in GC patients, thus necessitating the discovery and development of other potential treatment options. A growing body of knowledge about ferroptosis in different cancer types provides a new perspective in cancer therapeutics. Ferroptosis is an iron-dependent form of cell death. It is characterized by intracellular lipid peroxide accumulation and redox imbalance. In this review, we summarized the current findings of ferroptosis regulation in GC. We also tackled on the action of different potential drugs and genes in inducing ferroptosis for treating GC and solving drug resistance. Furthermore, we also explored the relationship between ferroptosis and the tumor microenvironment in GC. Finally, we discussed areas for future studies on the role of ferroptosis in GC to accelerate the clinical utility of ferroptosis induction as a treatment strategy for GC.

Association between neutrophil-lymphocyte ratio and lymph node metastasis in gastric cancer: A meta-analysis

INTRODUCTION AND AIM

The prognostic role of neutrophil to lymphocyte ratio (NLR) has been explored extensively in the literature. The aim of this meta-analysis was to evaluate the link between NLR and lymph node metastasis in gastric cancer. A method for increasing specificity and sensitivity of pre-treatment staging has implications on treatment algorithms and survival.

SEARCH STRATEGY

The relevant databases were searched as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses flowchart. After selection, 12 full text articles that met the inclusion criteria were included for quantitative analysis. 2 × 2 squares were generated using lymph node positive/negative, and NLR high/low data. The effect size for each study was calculated using the DerSimonian-Laird random effects model. P values were calculated using the chi-square method. Finally publication bias was evaluated. All statistics were calculated using R Studio.

RESULTS

Meta-analysis showed a 1.90 times (odds ratio, with 95% CI 1.52-2.38) increase in risk of positive lymph node status with high neutrophil to lymphocyte ratio. This has significant implications for cancer screening and staging, as NLR is a highly reproducible, cost-effective, and widely available prognostic factor for gastric cancer patients. Additionally, high or low NLR values may have implications for management pathways. Patients with lymph node metastasis can be offered neoadjuvant chemotherapy, avoiding salvage therapy in the form of adjuvant chemoradiotherapy, which is poorly tolerated.

CONCLUSION

This meta-analysis shows an association between NLR and positive lymph node status in gastric cancer patients with implications for staging, as well as preoperative personalisation of therapy.

Adjuvant Chemotherapy in Node-Negative Advanced Gastric Cancer Patients

Currently, there is still controversy on postoperative adjuvant chemotherapy for node-negative advanced gastric cancer. Herein, we sought to evaluate the role of postoperative adjuvant chemotherapy in these patients. We retrospectively analyzed the clinical and pathological characteristics of 363 node-negative advanced gastric cancer patients in our hospital from 1996 to 2007 who underwent gastrectomy and D2 lymphadenectomy. We compared the survival rate of the surgery-only group with that of the adjuvant chemotherapy treatment group. The 5-year survival rates of patients in the surgery-only group and the chemotherapy treatment group were 70.7% and 73.8%, respectively. There was no significant difference in the survival rate between patients receiving postoperative chemotherapy and patients not receiving chemotherapy (P=0.328). However, postoperative chemotherapy treatment significantly increased the survival rate of pT4aN0M0 patients (P=0.020), although it did not exert a direct effect on the survival rate in pT2N0M0 and pT3N0M0 patients (P=0.990 and P=0.895). We also summarized and analyzed the side effects and safety of postoperative adjuvant chemotherapy. The rate of chemotherapy-related adverse events was 79.9%. Although 61 (36.1%) patients had to adjust their chemotherapy dose, no patient died from side effects. In conclusion, postoperative chemotherapy treatment is safe but did not show a direct impact on the survival rate of the node-negative advanced gastric cancer patients. However, pT4aN0M0 patients can benefit from postoperative adjuvant chemotherapy after undergoing D2 radical resections.

Advances in screening and detection of gastric cancer

With an estimated one million new cases and 769 000 deaths in 2020, gastric cancer is the fifth most frequent cancer and fourth leading cause of cancer death globally. Incidence rates are highest in Asia and Eastern Europe. This manuscript will review the current modalities of diagnosis, staging, and screening of gastric cancer. We will also highlight development of novel diagnostics and advancements in endoscopic detection of early gastric cancer.

Construction of a miRNA Signature Using Support Vector Machine to Identify Microsatellite Instability Status and Prognosis in Gastric Cancer

Background. The specific role and prognostic value of DNA repair and replication-associated miRNAs in gastric cancer (GC) have not been clearly elucidated. Therefore, comprehensive analysis of miRNAs in GC is crucial for proposing therapeutic strategies and survival prediction. Methods. Firstly, clinical information and transcriptome data of TCGA-GC were downloaded from the database. In the entire cohort, we performed differential analysis in all miRNAs and support vector machine (SVM) was used to eliminate redundant miRNAs. Subsequently, we combined survival data and cox regression analysis to construct a miRNA signature in the training cohort. In addition, we used PCA, Kaplan-Meier, and ROC analysis to explore the prognosis value of risk score in the training and testing cohort. It is worth noting that multiple algorithms were used to evaluate difference of immune microenvironment (TME), microsatellite instability (MSI), tumor mutational burden (TMB), and immunotherapy in different risk groups. Finally, we investigated the potential mechanism about miRNA signature. Results. We constructed miRNA signature based on the following 4 miRNAs: hsa-miR-139-5p, hsa-miR-139-3p, hsa-miR-146b-5p, and hsa-miR-181a-3p. Univariate and multivariate Cox regression analyses suggested that risk score is a risk factor and an independent prognostic factor in GC patients. The AUC value of ROC analysis showed a robust prediction accuracy in each cohort. Moreover, significant differences in immune functions, immune cell content, immune checkpoint, MSI status, and TMB score were excavated in different groups distinguished by risk score. Finally, based on the above four miRNA target genes, we revealed that the signature was enriched in DNA repair and replication. Conclusion. We have developed a robust risk-formula based on 4 miRNAs that provides accurate risk stratification and prognostic prediction for GC patients. In addition, different risk subgroups may potentially guide the choice of targeted therapy.

Predictive value of preoperative handgrip strength on postoperative outcomes in patients with gastrointestinal tumors: a systematic review and meta-analysis

PURPOSE

This systematic review and meta-analysis aimed to explore the predictive value of preoperative handgrip strength on postoperative outcomes in patients with gastrointestinal tumors.

METHODS

Databases including Cochrane Library, Pubmed, Embase, Web of Science, and CINAHL Complete were searched for articles published from the establishment of database until August 7, 2021. Two researchers independently screened the literature, extracted the data, and evaluated the quality.

RESULTS

Eight studies were included, involving five prospective and three retrospective cohort studies with 2291 participants. The prevalence of preoperative low handgrip strength ranged from 11.8 to 62.7%. Preoperative low handgrip strength was associated with an increased risk of total complications (OR = 2.23, 95%CI = 1.43-3.50), pneumonia (OR = 5.16, 95%CI = 3.17-8.38), ileus (OR = 2.48, 95%CI = 1.09-5.65), and short-term mortality (OR = 7.28, 95%CI = 1.90-27.92).

CONCLUSION

This systematic review and meta-analysis indicated that preoperative HGS had important value to predict certain adverse postoperative outcomes among patients with GI tumors. Low handgrip strength criteria, definition of total complications, and country are the potential sources of heterogeneity, and more research are required to test and update these results.

Multicellular Modelling of Difficult-to-Treat Gastrointestinal Cancers: Current Possibilities and Challenges

Cancers affecting the gastrointestinal system are highly prevalent and their incidence is still increasing. Among them, gastric and pancreatic cancers have a dismal prognosis (survival of 5–20%) and are defined as difficult-to-treat cancers. This reflects the urge for novel therapeutic targets and aims for personalised therapies. As a prerequisite for identifying targets and test therapeutic interventions, the development of well-established, translational and reliable preclinical research models is instrumental. This review discusses the development, advantages and limitations of both patient-derived organoids (PDO) and patient-derived xenografts (PDX) for gastric and pancreatic ductal adenocarcinoma (PDAC). First and next generation multicellular PDO/PDX models are believed to faithfully generate a patient-specific avatar in a preclinical setting, opening novel therapeutic directions for these difficult-to-treat cancers. Excitingly, future opportunities such as PDO co-cultures with immune or stromal cells, organoid-on-a-chip models and humanised PDXs are the basis of a completely new area, offering close-to-human models. These tools can be exploited to understand cancer heterogeneity, which is indispensable to pave the way towards more tumour-specific therapies and, with that, better survival for patients.

Partial inclusion complex assisted crosslinked β-cyclodextrin nanoparticles for improving therapeutic potential of docetaxel against breast cancer

The present investigation demonstrates the development of crosslinked β-cyclodextrin nanoparticles (β-CD NPs) for enhancing the therapeutic efficacy of docetaxel (DTX) against breast cancer. Initially, a partial inclusion complex between β-CD and polypropylene glycol (PPG) was formed to induce self-assembly. This was followed by crosslinking of β-CDs using epichlorohydrin (EPI) and removal (by solubilization) of PPG to yield uniform β-CD NPs. The formed particles were used for loading DTX to form DTX β-CD NPs. The resultant DTX β-CD NPs exhibited particle size of 223.36 ± 17.73 nm with polydispersity index (PDI) of 0.13 ± 0.09 and showed entrapment efficiency of 54.53 ± 2%. Increased cell uptake (~5-fold), cytotoxicity (~3.3-fold), and apoptosis were observed in MDA-MB-231 cells when treated with DTX β-CD NPs in comparison to free DTX. Moreover, pharmacokinetic evaluation of DTX β-CD NPs revealed ~2 and ~5-fold increase in AUC0-∞ and mean residence time (MRT) of DTX when compared to Docepar®. Further, the anti-tumor activity using DMBA-induced cancer model showed that DTX β-CD NPs were capable of reducing the tumor volume to ~40%, whereas Docepar® was able to reduce tumor volume till ~80%. Finally, the toxicity evaluation of DTX β-CD NPs revealed no short-term nephrotoxicity and was confirmed by estimating the levels of biomarkers and histopathology of the organs. Thus, the proposed formulation strategy can yield uniformly formed β-CD NPs which can be effectively utilized for improving the therapeutic efficacy of DTX.

SERPINE1 Overexpression Promotes Malignant Progression and Poor Prognosis of Gastric Cancer

The serine protease inhibitor clade E member 1 (SERPINE1) is a major inhibitor of tissue plasminogen activator and urokinase, and has been implicated in the development and progression of a variety of tumors. In this study, mRNA microarray and TCGA database were used to comprehensively analyze the upregulation of SERPINE1 in gastric cancer (GC) tissues compared with the normal stomach tissues. Kaplan-Meier results confirmed that patients with high SERPINE1 expression exhibited worse overall survival and disease-free survival. In addition, cell proliferation, cell scratches, transwell migration and invasion assay showed that SERPINE1 knockdown inhibited the proliferation, migration and invasion of GC ells. Western blot showed that the expression of VEGF and IL-6 was significantly upregulated after overexpression of SERPINE1. Meanwhile, SERPINE1 was positively correlated with the level of immune infiltration using the online analysis tools TISIDB and TIMER. And SERPINE1 expression increased with the increase of malignancy of GC which were detected by Immunohistochemistry. Finally, tumorigenesis experiments in nude mice further demonstrated that SERPINE1 could promote the occurrence and development of GC, while deletion of SERPINE1 inhibited the progression of GC. In summary, SERPINE1 was highly expressed in GC tissues, and SERPINE1 was helpful for differential diagnosis of pathological grade of gastric mucosal lesions. SERPINE1 might regulate the expression of VEGF and IL-6 through the VEGF signaling pathway and JAK-STAT3 inflammatory signaling pathway, thus ultimately affecting the invasion and migration of GC cells.

Targeting ZFP64/GAL-1 axis promotes therapeutic effect of nab-paclitaxel and reverses immunosuppressive microenvironment in gastric cancer

Background

Chemoresistance is a main obstacle in gastric cancer (GC) treatment, but its molecular mechanism still needs to be elucidated. Here, we aim to reveal the underlying mechanisms of nanoparticle albumin-bound paclitaxel (nab-paclitaxel) resistance in GC.

Methods

We performed RNA sequencing (RNA-seq) on samples from patients who were resistant or sensitive to nab-paclitaxel, and identified Zinc Finger Protein 64 (ZFP64) as critical for nab-paclitaxel resistance in GC. CCK8, flow cytometry, TUNEL staining, sphere formation assays were performed to investigate the effects of ZFP64 in vitro, while subcutaneous tumor formation models were established in nude mice or humanized mice to evaluate the biological roles of ZFP64 in vivo. Chromatin immunoprecipitation sequencing (CHIP-seq) and double-luciferase reporter gene assay were conducted to reveal the underlying mechanism of ZFP64.

Results

ZFP64 overexpression was linked with aggressive phenotypes, nab-paclitaxel resistance and served as an independent prognostic factor in GC. As a transcription factor, ZFP64 directly binds to Galectin-1 (GAL-1) promoter and promoted GAL-1 transcription, thus inducing stem-cell like phenotypes and immunosuppressive microenvironment in GC. Importantly, compared to treatment with nab-paclitaxel alone, nab-paclitaxel plus GAL-1 blockade significantly enhanced the anti-tumor effect in mouse models, particularly in humanized mice.

Conclusions

Our data support a pivotal role for ZFP64 in GC progression by simultaneously promoting cellular chemotherapy resistance and tumor immunosuppression. Treatment with the combination of nab-paclitaxel and a GAL-1 inhibitor might benefit a subgroup of GC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-02224-x.

Significance of Lymph Node Metastasis in the Treatment of Gastric Cancer and Current Challenges in Determining the Extent of Metastasis

The stomach exhibits abundant lymphatic flow, and metastasis to lymph nodes is common. In the case of gastric cancer, there is a regularity to the spread of lymph node metastasis, and it does not easily metastasize outside the regional nodes. Furthermore, when its extent is limited, nodal metastasis of gastric cancer can be cured by appropriate lymph node dissection. Therefore, identifying and determining the extent of lymph node metastasis is important for ensuring accurate diagnosis and appropriate surgical treatment in patients with gastric cancer. However, precise detection of lymph node metastasis remains difficult. Most nodal metastases in gastric cancer are microscopic metastases, which often occur in small-sized lymph nodes, and are thus difficult to diagnose both preoperatively and intraoperatively. Preoperative nodal diagnoses are mainly made using computed tomography, although the specificity of this method is low because it is mainly based on the size of the lymph node. Furthermore, peripheral nodal metastases cannot be palpated intraoperatively, nodal harvesting of resected specimens remains difficult, and the number of lymph nodes detected vary greatly depending on the skill of the technician. Based on these findings, gastrectomy with prophylactic lymph node dissection is considered the standard surgical procedure for gastric cancer. In contrast, several groups have examined the value of sentinel node biopsy for accurately evaluating nodal metastasis in patients with early gastric cancer, reporting high sensitivity and accuracy. Sentinel node biopsy is also important for individualizing and optimizing the extent of uniform prophylactic lymph node dissection and determining whether patients are indicated for function-preserving curative gastrectomy, which is superior in preventing post-gastrectomy symptoms and maintaining dietary habits. Notably, advancements in surgical treatment for early gastric cancer are expected to result in individualized surgical strategies with sentinel node biopsy. Chemotherapy for advanced gastric cancer has also progressed, and conversion gastrectomy can now be performed after downstaging, even in cases previously regarded as inoperable. In this review, we discuss the importance of determining lymph node metastasis in the treatment of gastric cancer, the associated difficulties, and the need to investigate strategies that can improve the diagnosis of lymph node metastasis.

rs6426881 in the 3'-UTR of PBX1 is involved in breast and gastric cancers via altering the binding potential of miR-522-3p

BACKGROUND

Breast and gastric cancers are the most important diseases that lead to cancer death and social healthcare challenge. Overexpression of PBX1, a proto-oncogene, is correlated with the progression and metastasis of various cancers. For the first time, in this study the researchers evaluated the relationship between rs6426881, affecting miR-522-3p binding to the PBX1, with breast and gastric cancers.

METHODS AND RESULTS

The Microarray analysis was performed for finding the relative expression level of PBX1 and hsa-miR-522-3p, based on high throughput experiments. The GSE54397, GSE112369, GSE10810, GSE241585.ER, GSE24185.PR, GSE68373, and GSE38167 datasets were analyzed. A case-control study was carried out in 123 Iranian suffering from breast cancer and 132 participants as control samples as well as 130 people suffering from gastric cancer and 54 people as control group members. SNP rs6426881 in the 3'-UTR of PBX1 was genotyped by the High-Resolution Melting (HRM) method. Association analysis revealed that rs6426881 is correlated with Estrogen and Progesterone receptors, grade, and stage of breast cancer. Furthermore, a significant relationship was observed between the genotypes and blood groups in gastric cancer, while the distribution of alleles was significantly related to smoking, status of the primary tumor, and metastasis (Chi-Square P < 0.05). Finally, Bioinformatics analyses suggested that rs6426881 contains binding sites for miR-522-3p in the 3'-UTR of PBX1 transcript. The finding suggested that TT genotype is associated with poor prognosis in breast and gastric cancer.

CONCLUSIONS

The rs6426881 T allele at PBX1 3'-UT is significantly related to breast and gastric cancers by altering the regulatory affinity of miR-522-3p to PBX1 3'-UTR and may be suggested as a novel prognostic biomarker for the diseases.

Staging Laparoscopy for Assessing Inoperability in Gastrointestinal Malignancies

Background:

Despite the availability of modern cross-sectional diagnostic staging modalities, preoperative assessment of operability in intra-abdominal malignancy is often inadequate, especially in patients being considered for potential curative resection, resulting in many unnecessary laparotomies. Staging laparoscopy (SL) is usually undertaken in tertiary care centers, but the same has not been widely studied in India. The aim of the present study was to find out the possibility of diagnosing inoperability on SL and to study whether SL can prevent unnecessary laparotomy in cases of clinically diagnosed potentially resectable abdominal malignancies.

Methods:

This prospective diagnostics study was conducted in consecutive patients with gastrointestinal malignancies. All eligible patients were subjected to a thorough SL to look for inoperability before a therapeutic laparotomy. Statistical analysis of SL as a diagnostic modality was performed and the results were noted.

Results:

A total of 88 such patients were studied. The SL demonstrated inoperability in 24 out of the 88 (27.3%) patients. However, it failed to predict inoperability in 11 (12.5%) patients, yielding a sensitivity of 68.57% and specificity of 100%. The positive predictive value (PPV) of SL was 100%, whereas the negative predictive value (NPV) was 82.81% with efficacy of 87.5%.

Conclusions:

The specificity, PPV, NPV, and accuracy of SL to rule out inoperability in clinically diagnosed potentially resectable intra-abdominal gastrointestinal malignancies are noteworthy. The sensitivity of SL for the same purpose, though relatively low, may be augmented with practices such as liberal use of frozen section biopsy and intraoperative ultrasound. However, SL still fails to demonstrate unresectability due to locoregional advancement and aortocaval lymph node mets.

Efficacy and Safety of Additional S-1 Chemotherapy to S-1 Plus Oxaliplatin Regimen Chemotherapy for Stage III Gastric Carcinoma after Radical Resection

OBJECTIVE

To investigate the efficacy and safety of additional S-1 chemotherapy to S-1 plus oxaliplatin (SOX) regimen chemotherapy for Stage III gastric carcinoma (GC) after radical resection.

PATIENTS AND METHODS

A total of 161 patients who were pathologically diagnosed as Stage III GC after D2 gastrectomy and received SOX regimen adjuvant chemotherapy between January 2012 and April 2016 were included in this retrospective study. SOX regimen postoperative chemotherapy was composed of Oxaliplatin and S-1, administrated every 3 weeks for 8 scheduled courses. After SOX chemotherapy, 76 patients preferred additional chemotherapy with S-1 (the ACT group), while additional S-1 chemotherapy was not given to the other 85 patients (control group). The ACT with S-1 was administrated every 3 weeks for 8 scheduled courses. Treatment was terminated in case of life-threatening adverse events or tumor progression, or patients' demand for termination. Progression-free survival (PFS), overall survival (OS), and adverse events were analyzed.

RESULTS

ACT group obtained markedly improved 3-year PFS [p = 0.04; hazard ratio (HR) for disease progression, 0.58; 95% confidence interval (CI), 0.34-0.98] and OS than the control group (p = 0.0469; HR for death, 0.56; 95% CI, 0.32-0.99). No chemotherapy-related mortality occurred. Patients of the ACT group suffered more common and severer hand-foot syndrome (HFS) (p = 0.02).

CONCLUSIONS

Additional S-1 chemotherapy may be helpful for improving the disease progression and survival for patients with Stage III GC after radical resection with an acceptable safety profile.

Immune-Related Nine-MicroRNA Signature for Predicting the Prognosis of Gastric Cancer

Recent findings have demonstrated the superiority and utility of microRNAs (miRNAs) as new biomarkers for cancer diagnosis, therapy, and prognosis. In this study, to explore the prognostic value of immune-related miRNAs in gastric cancer (GC), we analyzed the miRNA-expression profiles of 389 patients with GC, using data deposited in The Cancer Genome Atlas database. Using a forward- and backward-variable selection and multivariate Cox regression analyses model, we identified a nine-miRNA signature (the “ImmiRSig,” consisting of miR-125b-5p, miR-99a-3p, miR-145-3p, miR-328-3p, miR-133a-5p, miR-1292-5p, miR-675-3p, miR-92b-5p, and miR-942-3p) in the training cohort that enabled the division of patients into high- and low-risk groups with significantly different survival rates. The ImmiRSig was successfully validated with an independent test cohort of 193 GC patients. Univariate and multivariate Cox regression analyses indicated that the ImmiRSig would serve as an independent prognostic factor after adjusting for other clinical covariates. Pending further prospective validation, the identified ImmiRSig appears to have significant clinical importance in terms of improving outcome predictions and guiding personalized treatment for patients with GC. Finally, significant associations between the ImmiRSig and the half-maximal inhibitory concentrations of chemotherapeutic agents were observed, suggesting that ImmiRSig may predict the clinical efficacy of chemotherapy.

A novel strategy to identify candidate diagnostic and prognostic biomarkers for gastric cancer

Background

Gastric cancer (GC) is one of the most common cancer worldwide. It is essential to identify non-invasive diagnostic and prognostic biomarkers of GC. The aim of the present study was to screen candidate biomarkers associated with the pathogenesis and prognosis of GC by a novel strategy.

Methods

The expression level of gene higher in cancer than in adjacent non-cancer tissue was defined as “positive”, and the top 5% genes with “positive rate” were filtered out as candidate diagnostic biomarkers in three Gene Expression Omnibus (GEO) datasets. Further, a prognostic risk model was constructed by multivariate Cox regression analysis in GEO dataset and validated in The Cancer Genome Atlas (TCGA). The expression level of candidate biomarkers was determined in serum and serum-derived exosomes of GC patients. Moreover, the effect of biomarkers in exosomes on migration of GC cells was analyzed by transwell assay.

Results

Ten candidate biomarkers (AGT, SERPINH1, WNT2, LIPG, PLAU, COL1A1, MMP7, MXRA5, CXCL1 and COL11A1) were identified with efficient diagnostic value in GC. A prognostic gene signature consisted of AGT, SERPINH1 and MMP7 was constructed and showed a good performance in predicting overall survivals in TCGA. Consistently, serum levels of the three biomarkers also showed high sensitivity and specificity in distinguishing GC patients from controls. In addition, the expression level of the three biomarkers were associated with malignant degree and decreased after surgery in GC patients. Moreover, the expression level of AGT and MMP7 in exosomes correlated positively with serum level. The exosomes derived from serum of GC patients can promote migration of SGC‐7901 cells. After neutralized the expression level of three proteins in exosomes with antibodies, the migration of GC cells was obviously suppressed.

Conclusions

Our findings provided a novel strategy to identify diagnostic biomarkers based on public datasets, and suggested that the three-gene signature was a candidate diagnostic and prognostic biomarker for patients with GC.

Prediction of Sensitivity and Efficacy of Clinical Chemotherapy Using Larval Zebrafish Patient-Derived Xenografts of Gastric Cancer

Background

Perioperative chemotherapy has been accepted as one of the most common approaches for locally advanced gastric cancer. However, the efficacy of chemotherapy varies among patients, and there is no effective method to predict the chemotherapy efficacy currently. We previously established the first larval zebrafish patient-derived xenografts (zPDXs) of gastric cancer as a platform for the translational research and personalized treatment. The objective of this study was to investigate the feasibility of screening individualized chemotherapeutics using the zPDXs.

Methods

We further optimized this zPDXs platform including administration route, drug dosing, and rhythm to develop a stable and reliable protocol for chemotherapeutics screening. Using the novel platform, we investigated the chemosensitivity of 5-fluorouracil, cisplatin, docetaxel, and doxorubicin for gastric cancer patients.

Results

We showed that the engrafted zebrafish retained the original prominent cell components of the corresponding human tumor tissues, and we successfully obtained the results of chemosensitivity of 5-fluorouracil, cisplatin, docetaxel, and doxorubicin for 28 patients with locally advanced gastric cancer. These patients underwent radical gastrectomy for curative intent and 27 cases received postoperative adjuvant chemotherapy. We revealed that the chemosensitivity obtained from zPDXs was consistent with the clinical responses in these patients (P = 0.029). More importantly, the responder drug(s) from zPDXs used or not was the only risk factor for early-stage recurrence in these 27 patients (P = 0.003).

Conclusion

Our study with the largest sample size so far suggests that larval zPDXs help to predict the chemotherapeutics response and to achieve precise chemotherapy for gastric cancer.

3D Multi-Attention Guided Multi-Task Learning Network for Automatic Gastric Tumor Segmentation and Lymph Node Classification

Automatic gastric tumor segmentation and lymph node (LN) classification not only can assist radiologists in reading images, but also provide image-guided clinical diagnosis and improve diagnosis accuracy. However, due to the inhomogeneous intensity distribution of gastric tumor and LN in CT scans, the ambiguous/missing boundaries, and highly variable shapes of gastric tumor, it is quite challenging to develop an automatic solution. To comprehensively address these challenges, we propose a novel 3D multi-attention guided multi-task learning network for simultaneous gastric tumor segmentation and LN classification, which makes full use of the complementary information extracted from different dimensions, scales, and tasks. Specifically, we tackle task correlation and heterogeneity with the convolutional neural network consisting of scale-aware attention-guided shared feature learning for refined and universal multi-scale features, and task-aware attention-guided feature learning for task-specific discriminative features. This shared feature learning is equipped with two types of scale-aware attention (visual attention and adaptive spatial attention) and two stage-wise deep supervision paths. The task-aware attention-guided feature learning comprises a segmentation-aware attention module and a classification-aware attention module. The proposed 3D multi-task learning network can balance all tasks by combining segmentation and classification loss functions with weight uncertainty. We evaluate our model on an in-house CT images dataset collected from three medical centers. Experimental results demonstrate that our method outperforms the state-of-the-art algorithms, and obtains promising performance for tumor segmentation and LN classification. Moreover, to explore the generalization for other segmentation tasks, we also extend the proposed network to liver tumor segmentation in CT images of the MICCAI 2017 Liver Tumor Segmentation Challenge. Our implementation is released at https://github.com/infinite-tao/MA-MTLN.

Comprehensive analysis of the prognostic value of the chemokine-like factor-like MARVEL transmembrane domain-containing family in gastric cancer

Background

The chemokine-like factor (CKLF)-like MARVEL transmembrane domain-containing (CMTM) family refers to a family of transcriptional repressor genes. CMTMs are closely associated with the epigenetic regulatory mechanisms and development of multiple malignancies, including gastric cancer. However, their specific biological functions and prognostic values in gastric cancer have yet to be elucidated.

Methods

Tumor sample datasets were retrieved and analyzed using databases including Oncomine, STRING, GEPIA2, cBioportal, and Kaplan-Meier plotter. To investigate the prognostic role of CMTMs in gastric cancer, we applied unsupervised hierarchical clustering analysis of CMTM gene expression patterns.

Results

While the mRNA levels of CMTM1/3/6/7/8 were upregulated in gastric cancer, CMTM2/4/5 showed no statistically significant difference at the mRNA level in patients with gastric cancer. Moreover, the mRNA expressions of different CMTMs exhibited strong correlations with various clinical parameters of patients with gastric cancer, including tumor stage, metastatic lymph node status, H. pylori status, and tumor grade. Also, the results suggested that elevated levels of CMTM3/5 mRNA had a significant association (P<0.05) with poor overall survival, progression-free survival, and post-progression survival. Conversely, elevated expression of CMTM2/4/6 mRNA had a significant association with better overall survival, progression-free survival, and post-progression survival. Unsupervised hierarchical clustering analysis successfully identified 2 major clusters of patients as follows: signature #1: CMTM4/6/8 and signature #2: CMTM1/2/3/5/7. Signature #2 was closely correlated with poorer overall survival, which indicated that the expression pattern of the CMTM family could be a novel prognostic factor for patients with gastric cancer.

Conclusions

These results suggest that the expression levels of CMTM genes possibly have prognostic value as a biomarker of gastric cancer.

Beyond the Guidelines: The Grey Zones of the Management of Gastric Cancer. Consensus Statements from the Gastric Cancer Italian Network (GAIN)

BACKGROUND

Management of gastric and gastroesophageal junction (GEJ) adenocarcinoma remains challenging, because of the heterogeneity in tumor biology within the upper gastrointestinal tract. Daily clinical practice is full of grey areas regarding the complexity of diagnostic, staging, and therapeutic procedures. The aim of this paper is to provide a guide for clinicians facing challenging situations in routine practice, taking a multidisciplinary consensus approach based on available literature.

METHODS

The GAIN (GAstric cancer Italian Network) group was established with the aims of reviewing literature evidence, discussing key issues in prevention, diagnosis, and management of gastric and GEJ adenocarcinoma, and offering a summary of statements. A Delphi consensus method was used to obtain opinions from the expert panel of specialists.

RESULTS

Forty-nine clinical questions were identified in six areas of interest: role of multidisciplinary team; risk factors; diagnosis; management of early gastric cancer and multimodal approach to localized gastric cancer; treatment of elderly patients with locally advanced resectable disease; and treatment of locally advanced and metastatic cancer.

CONCLUSIONS

The statements presented may guide clinicians in practical management of this disease.

Traditional Chinese Medicine Enhances Survival in Patients with Gastric Cancer after Surgery and Adjuvant Chemotherapy in Taiwan: A Nationwide Matched Cohort Study

Background

Gastric cancer remains a major cancer globally. More than half of patients with gastric cancer undergo surgery in Taiwan; however, few large nationwide studies have investigated the effects of traditional Chinese medicine (TCM) on gastric cancer management after surgery. This study aimed to evaluate the effect of TCM on patients with gastric cancer following surgery and adjuvant chemotherapy in Taiwan and its prescription trends.

Methods and Materials

The cohort sampling data set was obtained from the Registry of Catastrophic Illness Patient Database, a research database of patients with severe illnesses from the National Health Insurance Research Database, Taiwan. Patients who had received a new diagnosis of gastric cancer and had undergone surgery were enrolled. We matched TCM users and nonusers at a ratio of 1 : 3 based on the propensity score, and TCM users were also grouped into short-term and long-term users.

Results

The number of TCM users and nonusers was 1701 and 5103 after applying the propensity score at a ratio of 1 : 3. Short-term users and long-term TCM users were independently associated with a decreased risk of death with HRs of 0.59 (95% confidence interval (CI), 0.55–0.65) and 0.41 (95% CI, 0.36–0.47), respectively, compared with TCM nonusers. We also obtained similar results when we adjusted for covariates in the main model, as well as each of the additional listed covariates. We also observed similar HR trends in short-term users and long-term TCM users among men and women aged <65 years and ≥65 years. The most commonly prescribed single herb and herbal formula in our cohort were Hwang-Chyi (Radix Hedysari; 11.8%) and Xiang-Sha-Liu-Jun-Zi-Tang (15.5%), respectively.

Conclusion

TCM use was associated with higher survival in patients with gastric cancer after surgery and adjuvant chemotherapy. TCM could be used as a complementary and alternative therapy in patients with gastric cancer after surgery and adjuvant chemotherapy.

HOXA10 mediates epithelial-mesenchymal transition to promote gastric cancer metastasis partly via modulation of TGFB2/Smad/METTL3 signaling axis

Background

Homeobox A10 (HOXA10) belongs to the HOX gene family, which plays an essential role in embryonic development and tumor progression. We previously demonstrated that HOXA10 was significantly upregulated in gastric cancer (GC) and promoted GC cell proliferation. This study was designed to investigate the role of HOXA10 in GC metastasis and explore the underlying mechanism.

Methods

Immunohistochemistry (IHC) was used to evaluate the expression of HOXA10 in GC. In vitro cell migration and invasion assays as well as in vivo mice metastatic models were utilized to investigate the effects of HOXA10 on GC metastasis. GSEA, western blot, qRT-PCR and confocal immunofluorescence experiments preliminarily analyzed the relationship between HOXA10 and EMT. ChIP-qPCR, dual-luciferase reporter (DLR), co-immunoprecipitation (CoIP), colorimetric m⁶A assay and mice lung metastasis rescue models were performed to explore the mechanism by which HOXA10 accelerated the EMT process in GC.

Results

In this study, we demonstrated HOXA10 was upregulated in GC patients and the difference was even more pronounced in patients with lymph node metastasis (LNM) than without. Functionally, HOXA10 promoted migration and invasion of GC cells in vitro and accelerated lung metastasis in vivo. EMT was an important mechanism responsible for HOXA10-involved metastasis. Mechanistically, we revealed HOXA10 enriched in the TGFB2 promoter region, promoted transcription, increased secretion, thus triggered the activation of TGFβ/Smad signaling with subsequent enhancement of Smad2/3 nuclear expression. Moreover, HOXA10 upregulation elevated m⁶A level and METTL3 expression in GC cells possible by regulating the TGFB2/Smad pathway. CoIP and ChIP-qPCR experiments demonstrated that Smad proteins played an important role in mediating METTL3 expression. Furthermore, we found HOXA10 and METTL3 were clinically relevant, and METTL3 was responsible for the HOXA10-mediated EMT process by performing rescue experiments with western blot and in vivo mice lung metastatic models.

Conclusions

Our findings indicated the essential role of the HOXA10/TGFB2/Smad/METTL3 signaling axis in GC progression and metastasis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-01859-0.

Development of a simplified tumor-lymph node ratio classification system for patients with resected gastric cancer: A western study

INTRODUCTION

Gastric cancer (GC) shows high recurrence and mortality rates. The AJCC TNM staging system is the best prognostic predictor, but lymph node assessment is a major source of controversy. Recent studies have found that lymph node ratio (LNR) may overcome TNM limitations. Our aim is to develop a simplified tumor-LNR (T-LNR) classification for predicting prognosis of resected GC.

METHODS

Retrospective study of all GC resected in a tertiary center in Spain (N = 377). Clinicopathological features were assessed, LNR was classified into N0:0%, N1:1-25%, N2:>25%, and a T-LNR classification was developed. Statistical analyses were performed.

RESULTS

317 patients were finally included. Most patients were male (54.6%) and mean age was 72 years. Tumors were intestinal (61%), diffuse (30.8%) or mixed (8.1%). During follow-up, 36.7% and 27.4% of patients progressed and died, respectively. T-LNR classification divided patients into five prognostic categories (S1-S5). Most cases were S1-S4 (26.2%, 19.9%, 22.6% and 23.6%, respectively). 7.6% of tumors were S5. T-LNR classification was significantly associated with tumor size, depth, macroscopical type, Laurén subtype, signet ring cells, histologic grade, lymphovascular invasion, perineural infiltration, infiltrative growth, patient progression and death. Kaplan-Meier curves for OS showed an excellent patient stratification with evenly spaced curves. As for DFS, T-LNR classification also showed good discriminatory ability with non-overlapping curves. T-LNR classification was independently related to both OS and DFS.

CONCLUSIONS

T-LNR classifications can successfully predict prognosis of GC patients. Larger studies in other geographic regions should be performed to refine this classification and to validate its prognostic relevance.

Integrated Profiling Revealed Potential Regulatory Networks Among Long Noncoding RNAs and mRNAs in Mucosal Gastric Cancer

Gastric cancer is one of the most commonly occurring cancers worldwide. Investigation of long noncoding RNAs is of increasing interest, particularly in relation to their contribution to progression and prognosis of gastric cancers; however, insufficient studies been performed investigating the part of long noncoding RNAs play in gastric cancer carcinogenesis. Patterns of dysregulated long noncoding RNA and messenger RNA between mucosa gastric cancer and adjacent normal tissues were identified using long noncoding RNAs microarray analysis. Quantitative real-time polymerase chain reaction was conducted as a means to verify the obtained data. Both Gene Ontology and Kyoto Encyclopedia of Genes and Genomes  (KEGG) pathway analyses were subsequently used to investigate the function of dysregulated long noncoding RNAs and messenger RNAs. Cis and trans action was used to predict the possible targets of long noncoding RNAs, and a coexpression network was created to simulate the complex intergenic interactions. Ninety-five dysregulated long noncoding RNAs and 123 messenger RNAs were identified, and quantitative real-time polymerase chain reaction was used to validate 6 filtered long noncoding RNAs. Gene Ontology and KEGG pathway analyses identified several remarkably biological processes and signaling pathways, including spliceosome, RNA transport, and ubiquitin-mediated proteolysis. The transcriptional factors MYC, GABPA, and E2F1 were found to play a central function in the long noncoding RNAs process, as indicated by the coexpression network. This study revealed the dysregulated long noncoding RNA profiles of mucosal gastric cancer. The results shed light on the biological function of long noncoding RNAs in gastric cancer pathogenesis. This provides useful information for exploring potential early screening biomarkers in gastric cancer.

Which Lymph Node Staging System Better Predicts Prognosis in Patients With Gastric Carcinoma? A Comparative Study Between 3 Different Lymph Node Classifications for Resected Gastric Cancer in a Western Tertiary Center

INTRODUCTION

Gastric cancer (GC) is an aggressive disease with high mortality rates. Lymph node (LN) staging of GC is a major source of controversy. The aim of this study is to compare the prognostic value of 3 different LN classifications for patients with resected GC: the eighth TNM staging system, lymph node ratio (LNR, ratio between positive and total LN) and a new anatomic-based classification (Choi classification).

MATERIALS AND METHODS

A retrospective study of all cases of GC resected in a tertiary hospital in Spain (n=377). Clinical data were collected; histologic slides were reviewed; and univariate and multivariate analyses of disease-free survival (DFS) and overall survival (OS) were performed.

RESULTS

In all, 315 patients fulfilled inclusion criteria. Univariate analysis showed that all classifications were significantly associated with tumor death and progression (P<0.001). All staging systems were independent prognostic factors for DFS. Area under the curve ratios for Choi, N stage, and LNR classifications were 0.738, 0.730, and 0.735, respectively. TNM and LNR classifications were independent prognosticators for OS, while Choi classification was an independent factor only in patients with ≥16 LN resected. Area under the curve ratios for Choi, N stage, and LNR classifications were 0.707, 0.728, and 0.732, respectively. Kaplan-Meier curves depending on LNR classification showed the best patient stratification for both OS and DFS.

CONCLUSIONS

The 3-staging systems had similar prognostic performance, but LNR-based classification stratified patients better. Further studies are needed to evaluate the impact of the number of LN examined, cutoff values, and anatomic extent of LN disease in GC.

Influencing Factors and Effects of Treatment on Quality of Life in Patients With Gastric Cancer-A Systematic Review

Background: Gastric cancer (GC) is one of the leading causes of death worldwide. It is associated with several disease-related impairments contributing to the psycho-social burden of those patients, such as deterioration of well-being and overall quality of life (QOL). The aim of this study is to present the wide range of factors potentially impacting patients' overall well-being and possible preventive interventions. Methods: This systematic review was conducted in October 2020 with a search in the PubMed, MedLine, PsycInfo, and Google Scholar databases. We used the keywords "gastric cancer," "gastric neoplasm," and each of them combined with "quality of life," "depression," and "anxiety" to identify all relevant articles reporting about potential impact factors influencing the overall well-being of patients suffering from gastric cancer. Results: Finally, 125,490 articles were found, of which 125,431 were excluded in several steps of screening. Inclusion criteria were studies carried out on human ≥18 years of age, studies in English or German language, clinical trials, registry-based studies, cohort studies, population-based studies, and certain titles and abstracts. After screening for eligibility 35 potential factors influencing overall well-being in patients with GC were identified and classified into 9 important categories: genetic condition, treatment method, blood markers, nutritional status, daily living, state of health, mental state, supportive care, and alternative treatment. Conclusion: Since various factors are involved in the development of patients' overall well-being, timely treatment of psycho-social impairments by physicians and psychologists is of enormous importance. Preventing psycho-social burden by improving patients' QOL should be of high importance in the treatment regimen of patients with GC.

Deep Convolutional Neural Network Based on Computed Tomography Images for the Preoperative Diagnosis of Occult Peritoneal Metastasis in Advanced Gastric Cancer

We aimed to develop a deep convolutional neural network (DCNN) model based on computed tomography (CT) images for the preoperative diagnosis of occult peritoneal metastasis (OPM) in advanced gastric cancer (AGC). A total of 544 patients with AGC were retrospectively enrolled. Seventy-nine patients were confirmed with OPM during surgery or laparoscopy. CT images collected during the initial visit were randomly split into a training cohort and a testing cohort for DCNN model development and performance evaluation, respectively. A conventional clinical model using multivariable logistic regression was also developed to estimate the pretest probability of OPM in patients with gastric cancer. The DCNN model showed an AUC of 0.900 (95% CI: 0.851-0.953), outperforming the conventional clinical model (AUC = 0.670, 95% CI: 0.615-0.739; p < 0.001). The proposed DCNN model demonstrated the diagnostic detection of occult PM, with a sensitivity of 81.0% and specificity of 87.5% using the cutoff value according to the Youden index. Our study shows that the proposed deep learning algorithm, developed with CT images, may be used as an effective tool to preoperatively diagnose OPM in AGC.

Circular RNA circ_C16orf62 Suppresses Cell Growth in Gastric Cancer by miR-421/Tubulin beta-2A Chain (TUBB2A) Axis

Background

Gastric cancer (GC) is the third leading cause of cancer-associated mortality in the world. Expression of circular RNA circ_C16orf62 is reported to be low in GC. The role and mechanism of circ_C16orf62 remain unclear.

Material/Methods

Expression levels of circ_C16orf62 and tubulin beta-2A chain (TUBB2A) in GC tissues and cells, and microRNA-421 (miR-421) level in GC cells were detected by real-time quantitative polymerase chain reaction (RT-qPCR). The predominant cytoplasmic localization of circ_C16orf62 was identified by subcellular fractionation. The protein level of TUBB2A was detected by western blot assay. Cell proliferative ability, migration, and invasion were measured by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT), colony formation, and several transwell assaysy. The binding relationship between miR-421 and circ_C16orf62 or TUBB2A was predicted by starBase3.0 or Targetscan, and then verified by the dual-luciferase reporter assay. The biological role ofcirc_C16orf62 was examined by xenograft tumor model in vivo.

Results

Circ_C16orf62 andTUBB2A were downregulated in GC tissues and cells. Circ_C16orf62 was predominantly located in the cytoplasm of GC cells, and repressed proliferation, migration, and invasion of GC cells. Mechanistically, circ_C16orf62 worked as the miR-421 sponge to upregulate TUBB2A in GC, thereby hindering GC growth. Circ_C16orf62 repressed GC tumor growth in vivo.

Conclusions

These findings demonstrate that circ_C16orf62 impeded proliferation, migration, and invasion in vitro and retarded tumor growth in vivo by the miR-421/TUBB2A axis in GC, providing a potential therapeutic strategy for patients with GC.