RAE1 promotes gastric carcinogenesis and epithelial-mesenchymal transition

AIMS

The purpose of this study was to explore the role of RAE1 in the invasion and metastasis of gastric cancer (GC) cells.

MATERIALS AND METHODS

RAE1 expression in GC cells was determined by reverse-transcription polymerase chain reaction (qRT-PCR) and Western blotting (WB). Cell models featuring RAE1 gene silencing and overexpression were constructed by lentiviral transfection; The proliferation, migration, and invasion ability of cells were detected by cell counting, colony formation assay, would healing assay, and transwell invasion and migration test. WB analysis of ERK/MAPK signaling pathway (ERK1/2, p-ERK1/2, c-Myc) and EMT-related molecules (ZEB1, E-cadherin, N-cadherin, and Vimentin).

RESULTS

The expression level of RAE1 in GC was notably higher than in adjacent tissues. Elevated RAE1 expression correlated with an unfavorable prognosis for GC patients. Knockdown of RAE1, as compared to the control group, resulted in a significant inhibition of proliferation, migration, and invasion abilities in GC cell lines. Furthermore, RAE1 knockdown led to a substantial decrease in the expression of N-cadherin, vimentin, ZEB1, p-ERK1/2, and c-Myc proteins, coupled with a marked increase in E-cadherin expression. The biological effects of RAE1 in GC cells were effectively reversed by the inhibition of the ERK/MAPK signaling pathway using SCH772984. Additionally, RAE1 knockdown demonstrated a suppressive effect on GC tumor size in vivo. Immunohistochemistry (IHC) results revealed significantly lower expression of Ki-67 in RAE1 knockout mice compared to the control group.

CONCLUSIONS

RAE1 promotes GC cell migration and invasion through the ERK/MAPK pathway and is a potential therapeutic target for GC therapy.

Impact of endoscopic surveillance on the early diagnosis and endoscopic resection likelihood of gastric cancer

BACKGROUND

Endoscopy could help detect early gastric cancer (EGC) and improve the prognosis of patients. The aim of this study was to analyze the impact of endoscopy and endoscopic surveillance on the early detection of gastric cancer (GC), GC staging, and treatment selection.

METHODS

Patients with GC diagnosed at our center from 2010 to 2022 were retrospectively analyzed and allocated to the short-interval group (had received endoscopy within 3 years before diagnosis), the long-interval group (had received endoscopy more than 3 years before diagnosis), and the unchecked group (had not received endoscopy before diagnosis). The differences in GC staging and treatment modalities among the three groups were analyzed, and the differences in the clinical and pathological features of EGC were further analyzed.

RESULTS

One thousand and twenty-five GC patients were included, with 395 cases of EGC and 630 cases of advanced GC. The proportions of EGC in the short-interval, long-interval, and unchecked groups were 98.0%, 84.2%, and 29.8%, respectively (p < 0.001). Among the 387 lesions of 367 EGC patients were resected by endoscopic submucosal dissection (ESD), 341 (88.1%) exhibited curative resection, and 46 (11.9%) involved noncurative resections. Lesions of EGC differed significantly in diameter, depth of invasion, and curative resection rate (p = 0.033, 0.019, and 0.005, respectively). In the short-interval group, 87.8% of the lesions were ≤ 2 cm, 95.6% of the invasion depths were confined to the mucosal layer, and 96.7% of the eCura scores were A or B. Compared with the unchecked group, they had smaller diameters (RR = 0.419, 95% CI 0.234-0.752), shallower invasion depths (RR = 0.286, 95% CI 0.105-0.777), and a higher curative resection rate (RR = 0.215, 95% CI 0.068-0.676).

CONCLUSION

Endoscopic surveillance at 3-year intervals can help detect EGC, and the EGC lesions found have smaller diameters and shallower depths of invasion, helping improve the curative resection rate of ESD.

Appraisal of surgical outcomes and oncological efficiency of intraoperative adverse events in robotic radical gastrectomy for gastric cancer

BACKGROUND

Surgical quality control is a crucial determinant of evaluating the tumor efficacy.

OBJECTIVE

To assess the ClassIntra grade for quality control and oncological outcomes of robotic radical surgery for gastric cancer (GC).

METHODS

Data of patients undergoing robotic radical surgery for GC at a high-volume center were retrospectively analyzed. Patients were categorized into two groups, the intraoperative adverse event (iAE) group and the non-iAE group, based on the occurrence of intraoperative adverse events. The iAEs were further classified into five sublevels (ranging from I to V according to severity) based on the ClassIntra grade. Surgical performance was assessed using the Objective Structured Assessment of Technical Skill (OSATS) and the General Error Reporting Tool.

RESULTS

This study included 366 patients (iAE group: n = 72 [19.7%] and non-iAE group: n = 294 [80.3%]). The proportion of ClassIntra grade II patients was the highest in the iAE group (54.2%). In total and distal gastrectomies, iAEs occurred most frequently in the suprapancreatic area (50.0% and 54.8%, respectively). In total gastrectomy, grade IV iAEs were most common during lymph node dissection in the splenic hilum area (once for bleeding [grade IV] and once for injury [grade IV]). The overall survival (OS) and disease-free survival of the non-iAE group were significantly better than those of the iAE group (Log rank P < 0.001). Uni- and multi-variate analyses showed that iAEs were key prognostic indicators, independent of tumor stage and adjuvant chemotherapy (P < 0.001).

CONCLUSION

iAEs in patients who underwent robotic radical gastrectomy significantly correlated with the occurrence of postoperative complications and a poor long-term prognosis. Therefore, utilization and inclusion of ClassIntra grading as a crucial surgical quality control and prognostic indicator in the routine surgical quality evaluation system are recommended.

Efficacy and safety of neoadjuvant therapy in gastroenteropancreatic neuroendocrine neoplasms: A systematic review and meta-analysis

OBJECTIVE

To determine the effectiveness and safety of neoadjuvant therapy in gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) and provide evidence-based suggestions for clinical treatment.

METHODS

The Cochrane Library, Embase, PubMed, and Web of Science were searched for articles published that analyzed the effectiveness and safety of GEP-NEN-targeted neoadjuvant therapy before March 2023. A confidence interval (CI) of 95%, a subgroup analysis, heterogeneity, and effect size (ES) were analyzed, and a meta-analysis of the literature was performed using the Stata BE17 software.

RESULTS

A total of 417 patients from 13 studies were included in this meta-analysis. The primary variables comprised the objective response rate (ORR), disease control rate (DCR), surgical resection rate, and R0 resection rate with ES values of 0.42 (95% CI: 0.25-0.60), 0.96 (95% CI: 0.93-0.99), 0.67 (95% CI: 0.50-0.84), and 0.60 (95% CI: 0.54-0.67), respectively. The secondary variables were the incidence rates of treatment-related adverse events (TRAEs), Grade 3 or higher TRAEs, and surgical complications with ES values of 0.29 (95% CI: -0.03-0.21), 0.13 (95% CI: -0.07-0.33), and 0.35 (95% CI: 0.27-0.44), respectively.

CONCLUSION

Neoadjuvant therapy is an effective and safe treatment method for GEP-NENs. However, further studies are required to determine the optimal regimen for this therapy in these tumors.

Safety and efficacy of apatinib in combination with chemotherapy with or without immunotherapy versus chemotherapy alone as first-line treatment for advanced gastric cancer

The specific first-line regimen for advanced gastric cancer (GC) is still controversial. The benefit of apatinib for first-line treatment of advanced GC remains unknown and needs to be further explored. Eighty-two patients with advanced GC treated in our institution from October 2017 to March 2023 were retrospectively reviewed. All individuals had her-2 negative GC and had received at least two cycles of first-line treatment, including 44 patients in the combination treatment group (apatinib in combination with chemotherapy with or without immunotherapy) and 38 patients in the simple chemotherapy group. We evaluated the efficacy and safety of apatinib in combination with chemotherapy with or without immunotherapy in the first-line treatment of advanced GC by comparing the efficacy, progression-free survival (PFS), and adverse events in two groups of patients. The median PFS of the simple chemotherapy group was 9.25 months (95% confidence interval (CI), 6.1-11.2 months), and that of the combination treatment group was 10.9 months (95% CI, 7.9-15.8 months), which was 1.65 months longer than the simple chemotherapy group. Statistically significant differences are shown (P = 0.022). The objective response rate (ORR) of the combination treatment group was 65.9%, and 36.8% in the simple chemotherapy group. Statistically significant differences are shown (P = 0.014). No serious (Grade IV) adverse events occurred in either group. Our study indicates that apatinib in combination with chemotherapy with or without immunotherapy as first-line treatment for advanced GC exhibits good anti-tumor activity and is well tolerated by patients.

Meningeal carcinomatosis with decreased visual acuity: a case report

Meningeal carcinomatosis is a condition in which cancer cells diffusely metastasize to the cerebral pia mater in the cerebrospinal membrane or cerebrospinal cavity. It causes a wide array of symptoms according to the site of metastasis. The prognosis is poor, especially in metastasis from solid tumors. This study reports a case of meningeal carcinomatosis caused by advanced gastric cancer, manifested by headache and vision loss. The patient was a 69-year-old man who underwent head computed tomography (CT) and magnetic resonance imaging (MRI) for persistent headaches. No abnormal findings were found; however, his vision declined, convulsions occurred, and cerebrospinal fluid (CSF) cytology showed poorly differentiated adenocarcinoma. Therefore, meningeal carcinomatosis was diagnosed. The patient died after receiving FOLFOX therapy to relieve symptoms and prolong his life. An autopsy showed no invasion of the optic nerve or surrounding tissues. As the frequency of complications of meningeal carcinomatosis in solid cancers is rare, it is crucial to actively suspect and make an early diagnosis.

Laparoscopic resection of a gastric duplication cyst located near the esophagogastric junction

We herein describe the rare case of a patient with a gastric duplication cyst who underwent laparoscopic resection. A 67-year-old man was referred to our hospital with an intra-abdominal lesion incidentally diagnosed on abdominal computed tomography. Esophagogastroduodenoscopy revealed normal esophageal and gastric mucosa without any lesions. Abdominal contrast-enhanced computed tomography revealed an 18 mm well-defined mass adjacent to the lesser curvature side of the esophagogastric junction. Following clinical diagnosis as an intra-abdominal mass, the patient underwent laparoscopic surgery in a five-port setting. The lesion originated from the stomach, near the muscular layer. The stomach muscle layer was partially resected; however, no communication between the mass and gastric mucosa was identified. Macroscopically, the resected specimen was 19 × 18 mm with a smooth surface and distinct margins. Microscopic examination confirmed the diagnosis of a gastric duplication cyst. The inner surface was covered with gastric gland pit-type columnar epithelial cells without atypia or neoplastic changes. The cyst wall presented layers of mucosa, muscularis mucosae, submucosa, muscularis propria, and subserosa. The patient's course after the procedure was uneventful, and he was discharged 8 days postoperatively. Gastric duplication cysts are rare and mostly asymptomatic, and their laparoscopic partial resection is safe and effective.

Quercetin promotes ATG5-mediating autophagy-dependent ferroptosis in gastric cancer

Quercetin has been documented to possess a multitude of pharmacological effects, encompassing antioxidant, antiviral, antimicrobial, and anti-inflammatory properties. Nevertheless, the exact molecular mechanisms responsible for the anti-tumor properties of quercetin remain to be fully explicated. To this end, quercetin was administered to gastric cancer cells (in vitro) AGS and MKN45, as well as BALB/c mice (in vivo). The proliferation ability of cells was evaluated using cholecystokinin octapeptide (CCK-8) and colony formation assays. The evaluation of ferroptosis involved the measurement of iron, malondialdehyde (MDA), and lipid reactive oxygen species. Autophagy and apoptosis were evaluated using immunofluorescence staining, western blotting, and flow cytometry analysis. Our findings indicate that quercetin significantly inhibited cell viability and tumor volume compared to the control group. Additionally, quercetin was found to decrease glutathione (GSH), malondialdehyde, and reactive oxygen species (ROS) levels while suppressing beclin1 and LC3B levels in cancer cells. Remarkably, the utilization of siATG5 was found to reverse all the aforementioned effects of quercetin. Ultimately, the effects of quercetin on gastric cancer were validated. In summary, our findings provide evidence that quercetin facilitates autophagy-mediated ferroptosis in gastric cancer.

[A Case of Interstitial Pneumonia Induced by Immune Checkpoint Inhibitors for Gastric Cancer During the COVID- 19 Pandemic]

BACKGROUND

The novel coronavirus disease(corona virus disease 2019: COVID-19)has calmed down worldwide, and the severity of the disease is decreasing. On the other hand, due to the emergence of strain mutations, the number of infected people shows a wavy course. I have experienced a case of gastric cancer that underwent chemotherapy including an immune checkpoint inhibitors(ICI) early after COVID-19, so I will report it including a discussion.

CASE

A 71-year-old man. The patient visited our hospital with a chief complaint of stomach discomfort, and gastrointestinal endoscopy revealed advanced gastric cancer accompanied by narrowing of the gastric lumen. The histopathological examination showed a poorly differentiated adenocarcinoma. A CT scan of the chest and abdomen showed thickening of the entire gastric wall, indicating the presence of enlarged adjacent lymph nodes and infiltration into adjacent organs. No other obvious distant metastases were observed. Staging laparoscopy was performed, it revealed infiltration of the posterior wall of the stomach into the celiac artery and anterior surface of the pancreas. We determined that curative resection would be difficult. As a result of planning chemotherapy for locally advanced gastric cancer, the patient contracted COVID-19 due to a hospital- acquired infection. The patient's COVID-19 infection was managed with supportive care alone without severe complications, and they recovered within the course of treatment. Two weeks after the onset of the infection, chemotherapy(FOLFOX+ Nivo)was initiated. The patient completed up to 9 courses of chemotherapy, and the treatment response was determined to be stable disease(SD). Due to a tendency of stenosis in the gastric lumen, the possibility of future dilation procedures was considered. As a result, the patient underwent second-line chemotherapy with a combination of wPTX+RAM. After completing 1 course of treatment, the patient developed drug-induced interstitial pneumonia, which was managed with intensive care and steroid pulse therapy, resulting in improvement. There was progression of gastric lumen stenosis, and an endoscopic dilation procedure/stent placement was performed. Subsequently, there was a rapid increase in malignant ascites and a decline in activities of daily living(ADL), leading to palliative care. Unfortunately, the patient succumbed to cancer-related complications 10 months after the diagnosis.

DISCUSSION

In this case, the serial antibody titers of COVID-19 also indicated the sustained effectiveness of the multi-drug combination chemotherapy. The treatment course suggests a suspicion of drug-induced interstitial pneumonia due to PTX/RAM, but the long-term imaging follow-up implies that ICI may be the cause. When using ICI, COVID-19 infection alone may pose a potential risk factor.

Metabolic heterogeneity affects trastuzumab response and survival in HER2-positive advanced gastric cancer

BACKGROUND

Trastuzumab is the only first-line treatment targeted against the human epidermal growth factor receptor 2 (HER2) approved for patients with HER2-positive advanced gastric cancer. The impact of metabolic heterogeneity on trastuzumab treatment efficacy remains unclear.

METHODS

Spatial metabolomics via high mass resolution imaging mass spectrometry was performed in pretherapeutic biopsies of patients with HER2-positive advanced gastric cancer in a prospective multicentre observational study. The mass spectra, representing the metabolic heterogeneity within tumour areas, were grouped by K-means clustering algorithm. Simpson's diversity index was applied to compare the metabolic heterogeneity level of individual patients.

RESULTS

Clustering analysis revealed metabolic heterogeneity in HER2-positive gastric cancer patients and uncovered nine tumour subpopulations. High metabolic heterogeneity was shown as a factor indicating sensitivity to trastuzumab (p = 0.008) and favourable prognosis at trend level. Two of the nine tumour subpopulations associated with favourable prognosis and trastuzumab sensitivity, and one subpopulation associated with poor prognosis and trastuzumab resistance.

CONCLUSIONS

This work revealed that tumour metabolic heterogeneity associated with prognosis and trastuzumab response based on tissue metabolomics of HER2-positive gastric cancer. Tumour metabolic subpopulations may provide an association with trastuzumab therapy efficacy.

CLINICAL TRIAL REGISTRATION

The patient cohort was conducted from a multicentre observational study (VARIANZ;NCT02305043).

M6A methylation of FKFB3 reduced pyroptosis of gastric cancer by NLRP3

Gastric cancer is a kind of malignant tumor that seriously endangers human life and health. Its incidence rate and mortality rate are among the highest in the global malignant tumors. Therefore, this study explored the role of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) in the progression of gastric cancer and its underlying mechanism. Patients with gastric cancer were collected, and human GC cell lines (stomach gastric carcinoma 7901, stomach gastric carcinoma 823 , human gastric carcinoma cell line 803 and adenocarcinoma gastric stomach) were used in this study. We utilized glucose consumption, cell migration, and ELISA assay kits to investigate the function of GC. To understand its mechanism, we employed quantitative PCR (qPCR), western blot, and m6A methylated RNA immunoprecipitation assay. FKFB3 protein expression levels in patients with gastric cancer were increased. The induction of PFKFB3 mRNA expression levels in patients with gastric cancer or gastric cancer cell lines. Gastric cancer patients with high PFKFB3 expression had a lower survival rate. PFKFB3 high expression possessed the probability of pathological stage, lymph node metastasis or distant metastasis in patients with gastric cancer. PFKFB3 upregulation promoted cancer progression and Warburg effect progression of gastric cancer. PFKFB3 upregulation reduced pyroptosis and suppressed nucleotidebinding domain, leucinerich repeat containing protein 3-induced pyroptosis of gastric cancer. M6A-forming enzyme methyltransferase-like 3 increased PFKFB3 stability. Taken together, the M6A-forming enzyme methyltransferase-like 3 increased PFKFB3 stability and reduced pyroptosis in the model of gastric cancer through the Warburg effect. The PFKFB3 gene represents a potential therapeutic strategy for the treatment of gastric cancer.

Xenograft and organoid models in developing precision medicine for gastric cancer (Review)

Gastric cancer (GC), a highly heterogeneous disease, has diverse histological and molecular subtypes. For precision medicine, well‑characterized models encompassing the full spectrum of subtypes are necessary. Patient‑derived tumor xenografts and organoids serve as important preclinical models in GC research. The main advantage of these models is the retention of phenotypic and genotypic heterogeneity present in parental tumor tissues. Utilizing diverse sequencing techniques and preclinical models for GC research facilitates accuracy in predicting personalized clinical responses to anti‑cancer treatments. The present review summarizes the latest advances of these two preclinical models in GC treatment and drug response assessment.

Alpha-fetoprotein-producing gastric cancer with ruptured liver metastasis mimicking hepatocellular carcinoma

Alpha-fetoprotein (AFP)-producing gastric cancer is a rare subtype of gastric cancer known for its aggressive nature. We present an uncommon case of a 60s male with multiple liver tumors, initially suggested as hepatocellular carcinoma (HCC) by imaging. However, a subsequent gastric biopsy revealed a poorly differentiated adenocarcinoma with hepatoid features, and liver biopsy mirrored these findings. The disease progressed swiftly, with the patient representing owing to the spontaneous rupture of a metastatic liver tumor, an extremely rare occurrence, especially in metastatic liver cancers. Such ruptures in AFP-producing gastric cancer may be attributed to the tumor's rich blood flow. Distinctly differentiating this subtype from HCC is pivotal for apt management, as was evident in our case. The diagnosis was particularly challenging due to the similarities in imaging presentations between AFP-producing gastric cancer liver metastasis and HCC. This case underscores the need for vigilant diagnosis, emphasizing the importance of liver biopsy, especially in the absence of chronic liver disease. It also highlights the potential complications, like spontaneous rupture, associated with this rare form of gastric cancer.

[A Case of Distal Gastrectomy and Left Segmentectomy for Hepatic Invasion of Gastric Cancer]

A 66-year-old male came to our hospital because of occult blood in stool and anemia. The patient was diagnosed as unresectable advanced gastric cancer,( ML/Less, type 2, tub2, cT4b[liver], cN+, cM0, cStage Ⅳ, HER2 negative). He was given oxaliplatin plus S-1 therapy. In the 3rd course of chemotherapy, he had severe anemia, and active bleeding from the tumor. To control the bleeding he underwent distal gastrectomy, lateral segmentectomy of the liver, and S4 partial hepatectomy. The patient underwent adjuvant chemotherapy with docetaxel plus S-1. Three months after surgery, lymph nodes recurrence was observed. He underwent second-line therapy with paclitaxel and ramucirumab. Seven months after surgery, lymph nodes recurrence was increased. He was switched to third-line therapy with nivolumab. He is currently arrive 12 months after surgery.

Postoperative Complications After Neoadjuvant Chemotherapy Versus Upfront Surgery in Gastric Adenocarcinoma: A Population-Based Nationwide Study in Finland

BACKGROUND

To date, no large population-based studies have compared complications and short-term outcomes between neoadjuvant chemotherapy and upfront surgery in gastric cancer. More nationwide studies with standardized reporting on complications are needed to enable international comparison between studies. This study aimed to compare postoperative complications between neoadjuvant therapy and upfront surgery after gastrectomy for gastric adenocarcinoma in a population-based setting.

METHODS

This population-based study based on the Finnish National Esophago-Gastric Cancer Cohort included all patients 18 years of age or older undergoing gastrectomy for gastric adenocarcinoma in Finland during 2005-2016. Logistic regression provided odds ratios (ORs) with 95% confidence intervals (CIs), both crude and adjusted for key confounders. Different types of complications were graded based on the Esophagectomy Complications Consensus Group definitions, and major complications were assessed by the Clavien-Dindo scale.

RESULTS

This study analyzed 769 patients. Neoadjuvant chemotherapy did not increase major postoperative complications after gastrectomy for gastric cancer compared with upfront surgery (OR, 1.12; 95% CI 0.81-1.56). Furthermore, it did not increase pneumonia, anastomotic complications, wound complications, or other complications.

CONCLUSIONS

Neoadjuvant therapy is not associated with increased postoperative complications, reoperations, or short-term mortality compared with upfront surgery in gastric adenocarcinoma.

Safe suprapancreatic lymph node dissection for gastric cancer with ectopic common hepatic artery

Suprapancreatic lymph node dissection for patients with gastric cancer in whom the common hepatic artery is located neither at the suprapancreatic margin nor in front of the portal vein is a more difficult procedure than when the common hepatic artery is in a more typical position. There is an increased risk of injury to the vessels that need to be preserved and inadequate lymph node dissection. Measures that have been reported for use in this situation are preoperative diagnosis with three-dimensional computed tomography angiography, dissection using the portal vain as a guide, and safe exposure of the portal vein with dissection to preserve the nerves at the suprapancreatic margin and in front of the portal vein. We review the literature and report our experience with a patient whose common hepatic artery was not located in the suprapancreatic margin who safely underwent suprapancreatic lymph node dissection using these methods.

IL-6 facilitates cross-talk between epithelial cells and tumor- associated macrophages in Helicobacter pylori-linked gastric carcinogenesis

PURPOSE

Helicobacter pylori (H. pylori) is a significant risk factor for development of gastric cancer (GC), one of the deadliest malignancies in the world. However, the mechanism by which H. pylori induces gastric oncogenesis remains unclear. Here, we investigated the function of IL-6 in gastric oncogenesis and macrophage-epithelial cell interactions.

METHODS

We analyzed publicly available datasets to investigate the expression of IL-6 and infiltration of M2 macrophages in GC tissues, and determine the inter-cellular communication in the context of IL-6. Human gastric epithelial and macrophage cell lines (GES-1 and THP-1-derived macrophages, respectively) were used in mono- and co-culture experiments to investigate autocrine-and paracrine induction of IL-6 expression in response to H. pylori or IL-6 stimulation.

RESULTS

We found that IL-6 is highly expressed in GC and modulates survival. M2 macrophage infiltration is predominant in GC and drives an IL-6 mediated communication with gastric epithelium cells. In vitro, IL-6 triggers its own expression in GES-1 and THP-1-derived macrophages cells. In addition, these cell lines are able to upregulate each other's IL-6 levels in an autocrine fashion, which is enhanced by H. pylori stimulation.

CONCLUSION

This study indicates that IL-6 in the tumor microenvironment is essential for intercellular communication. We show that H. pylori enhances an IL-6-driven autocrine and paracrine positive feedback loop between macrophages and gastric epithelial cells, which may contribute to gastric carcinogenesis.

BEST-J Score: Validation of a Predicting Model for Delayed Bleeding After Gastric Endoscopic Submucosal Dissection on a European Sample

BACKGROUND

Delayed bleeding (DB) is a possible adverse event following gastric endoscopic submucosal dissection (ESD). The BEST-J score was created as a risk prediction model for DB following gastric ESD, but is yet to be validated in Western populations.

AIMS

We aimed to validate the BEST-J score on a European sample and to perform a subgroup analysis according to histological classification.

METHODS

Retrospective study of all consecutive patients undergoing gastric ESD on a European Endoscopic Unit. DB was defined as hemorrhage with clinical symptoms and confirmed by emergency endoscopy from the time of completion to 28 days after ESD. BEST-J score was calculated in each patient and confronted with the outcome (DB).

RESULTS

Final sample included 161 patients. From these, 10 (6.2%) presented DB following ESD, with a median time to bleeding of 7 days (IQR 6.8). BEST-J score presented an excellent accuracy predicting DB in our sample, with an AUC = 0.907 (95%CI 0.801-1.000; p < 0.001). Subgroup analysis by histological classification proved that the discriminative power was still excellent for each grade: low-grade dysplasia-AUC = 0.970 (p < 0.001); high-grade dysplasia-AUC = 0.874 (p < 0.001); early gastric cancer-AUC = 0.881 (p < 0.001). The optimal cut-off value to predict DB was a BEST-J score ≥ 3, which matches the cut-off value for high-risk of bleeding in the original investigation.

CONCLUSIONS

The BEST-J score still presents excellent accuracy in risk stratification for post-ESD bleeding in European individuals. Thus, this score may help to guide which patients benefit the most from prophylactic therapies following gastric ESD in this setting.

[A Case of Stage Ⅳ Gastric Cancer with Multiple Liver Metastases, Resected Primary Tumor after Chemotherapy, and Alive for 3.5 Years without Recurrence]

A 67-year-old man visited our hospital for epigastric pain. Esophagogastroduodenoscopy(EGD)revealed type 2 gastric cancer from the cardia to the gastric angle, and histopathological examination revealed papillary adenocarcinoma(pap), HER2-positive. Contrast-enhanced CT showed wall thickening mainly in the posterior wall of the gastric body, enlarged lymph nodes that were lumped together with the main lesion, and 8 low-absorption areas with ring shaped contrast effects in both lobes of the liver. The patient was diagnosed as gastric cancer cT4aN(+)M1[HEP], clinical Stage ⅣB. Six courses of capecitabine plus cisplatin plus trastuzumab(XP plus Tmab)therapy and 17 courses of capecitabine plus trastuzumab(X plus Tmab)therapy were performed. After chemotherapy, liver and lymph node metastases disappeared on CT and MRI. EGD showed residual gastric cancer, and the policy was to resect the primary tumor. Laparoscopic total gastrectomy with D2 lymph node dissection was performed. Pathological results showed T1b(SM)depth, no lymph node metastasis, and histologic response was Grade 2a. Six courses of X plus Tmab were administered as postoperative adjuvant chemotherapy, but were discontinued at the patient's request. Currently, 5 years have passed since the first chemotherapy and 3.5 years have passed since the surgery, and the patient is alive without recurrence, suggesting that the conversion surgery may have contributed to the prolonged survival.

Abnormal activation of RFC3, A YAP1/TEAD downstream target, promotes gastric cancer progression

BACKGROUND

Gastric cancer (GC) is a malignant tumor with a high mortality rate, and thus, it is necessary to explore molecular mechanisms underlying its progression. While replication factor C subunit 3 (RFC3) has been demonstrated to function as an oncogene in many cancers, its role in GC remains unclear.

METHODS

Tumor tissues were collected from clinical GC patients, and the expression of RFC3 was analyzed. NCI-N87 and HGC-27 cells were infected with lentivirus sh-RFC3 to knock down RFC3 expression. RFC3 expression levels were determined, in addition to cell biological behaviors both in vitro and in vivo. The relationship between RFC3 and the YAP1/TEAD signaling pathway was detected by dual luciferase reporter assay.

RESULTS

RFC3 was upregulated in GC tumor tissues. RFC3 knockdown inhibited cell proliferation, promoted cell apoptosis of GC cells, and suppressed cell migration and invasion. Moreover, depleted RFC3 suppressed tumor growth and metastasis in vivo. Mechanistically, the YAP1/TEAD axis activated RFC3 expression transcriptionally by binding to the RFC3 promoter.

CONCLUSIONS

RFC3 was transcriptional activated by the YAP1/TEAD signaling pathway, thus promoting GC progression. RFC3 may be a promising therapeutic target for GC.

Downregulation of PDIA3 inhibits gastric cancer cell growth through cell cycle regulation

OBJECTIVE

Protein disulfide isomerase A3 (PDIA3) promotes the correct folding of newly synthesized glycoproteins in the endoplasmic reticulum. PDIA3 is overexpressed in most tumors, and it may become a biomarker of cancer prognosis and immunotherapy. Our study aims to detect the expression level of PDIA3 in gastric cancer (GC) and its association with GC development as wells as the underlying mechanisms.

METHODS

GC cell lines with PDIA3 knockdown by siRNA, CRISPR-cas9 sgRNAs or a pharmacological inhibitor of LOC14 were prepared and used. PDIA3 knockout GC cells were established by CRISPR-cas9-PDIA3 system. The proliferation, migration, invasion and cell cycle of GC cells were analyzed by cell counting kit-8 assay, wound healing assay, transwell assay and flow cytometry, respectively. Immunodeficient nude mice was used to evaluate the role of PDIA3 in tumor formation. Quantitative PCR and western blot were used for examining gene and protein expressions. RNA sequencing was performed to see the altered gene expression.

RESULTS

The expressions of PDIA3 in GC tissues and cells were increased significantly, and its expression was negatively correlated with the three-year survival rate of GC patients. Down-regulation of PDIA3 by siRNA, LOC14 or CRISPR-cas9 significantly inhibited proliferation, invasion and migration of GC cells TMK1 and AGS, with cell cycle arrested at G2/M phase. Meanwhile, decreased PDIA3 significantly inhibited growth of tumor xenograft in vivo. It was found that cyclin G1 (encoded by CCNG1 gene) expression was decreased by downregulation of PDIA3 in GC cells both in vitro and in vivo. In addition, protein levels of other cell cycle related factors including cyclin D1, CDK2, and CDK6 were also significantly decreased. Further study showed that STAT3 was associated with PDIA3-mediated cyclin G1 regulation.

CONCLUSION

PDIA3 plays an oncogenic role in GC. Our findings unfolded the functional role of PDIA3 in GC development and highlighted a novel target for cancer therapeutic strategy.

Intraoperative esophageal washout reduces free intraluminal tumor cells during resection of carcinomas of the esophagus and cardia

OBJECTIVE

Intraluminally shed viable tumor cells might contribute to anastomotic recurrence in cancer of the esophagus and the cardia. The study aimed to establish a method of esophageal washout and, hence, to reduce intraluminal cancer cells before esophageal anastomosis.

METHODS

Forty-eight consecutive patients with esophago-gastric resection for histologically proven cancer of the esophagus or the cardia were included in a prospective, interventional study. Before transection, the esophagus was clamped proximally to the tumor and rinsed with 1:10 diluted povidone-iodine-solution (10 × 30 ml) applied by a transorally inserted 24F-Foley catheter. The first, fifth and tenth portion of the lavage fluid were sent to cytological examination.

RESULTS

Intraoperative frozen sections confirmed clear proximal resection margins of the esophagus. The cytological examination of the fluid recovered from the esophageal washout revealed malignant cells in 13/48 patients (27%). The presence of malignant cells was significantly less likely in patients with neoadjuvant treatment than in patients without neoadjuvant treatment: 2/23 (9%) vs. 11/25 (44%) (p = 0.009). Repetitive washout reduced the probability of detectable malignant cells from 13 to 8 (62%) patients after 5, and further to 4 patients (30%) after 10 washout maneuvers.

CONCLUSIONS

Free malignant cells may be present in the esophageal lumen following intraoperative manipulation of cancers of the esophagus or cardia. Transoral washout of the esophagus is novel, feasible and enables reduction or even elimination of these tumor cells. The reliability of this procedure raises with increasing washout volume. Esophageal washout might be especially worthwhile in patients who do not receive neoadjuvant therapy.

A novel single-port robot for total gastrectomy to treat gastric cancer: A case report (with video)

Multiport robots are now widely used for total gastrectomy for gastric cancer, while there is almost a void of research on whether single-port (SP) robots can be used for total gastrectomy. Here, we report a case of a 75-year-old female patient who was diagnosed with gastric cardia adenocarcinoma by gastroscopy and underwent total gastrectomy assisted by the SHURUI SP robot. We successfully accomplished total gastrectomy and D2 lymph node dissection using the novel SP robotic platform. The patient was discharged from the hospital successfully with no complications during or after the surgery. Pathologic diagnosis showed adenocarcinoma of the gastric mucosa with partial signet-ring cell carcinoma, and no metastasis was found in the 29 cleared lymph nodes. The use of the SHURUI SP robot for total gastrectomy in treating gastric cancer is both technically feasible and safe.

Development and validation of a preoperative risk nomogram prediction model for gastric gastrointestinal stromal tumors

BACKGROUND AND STUDY AIMS

Gastrointestinal stromal tumors (GIST) carry a potential risk of malignancy, and the treatment of GIST varies for different risk levels. However, there is no systematic preoperative assessment protocol to predict the malignant potential of GIST. The aim of this study was to develop a reliable and clinically applicable preoperative nomogram prediction model to predict the malignant potential of gastric GIST.

PATIENTS AND METHODS

Patients with a pathological diagnosis of gastric GIST from January 2015 to December 2021 were screened retrospectively. Univariate and multivariate logistic analyses were used to identify independent risk factors for gastric GIST with high malignancy potential. Based on these independent risk factors, a nomogram model predicting the malignant potential of gastric GIST was developed and the model was validated in the validation group.

RESULTS

A total of 494 gastric GIST patients were included in this study and allocated to a development group (n = 345) and a validation group (n = 149). In the development group, multivariate logistic regression analysis revealed that tumor size, tumor ulceration, CT growth pattern and monocyte-to- lymphocyte ratio (MLR) were independent risk factors for gastric GIST with high malignancy potential. The AUC of the model were 0.932 (95% CI 0.890-0.974) and 0.922 (95% CI 0.868-0.977) in the development and validation groups, respectively. The best cutoff value for the development group was 0.184, and the sensitivity and specificity at this value were 0.895 and 0.875, respectively. The calibration curves indicated good agreement between predicted and actual observed outcomes, while the DCA indicated that the nomogram model had clinical application.

CONCLUSIONS

Tumor size, tumor ulceration, CT growth pattern and MLR are independent risk factors for high malignancy potential gastric GIST, and a nomogram model developed based on these factors has a high ability to predict the malignant potential of gastric GIST.

A preoperative predictive tool to assess the need for staging laparoscopy in oesophagogastric cancer patients

INTRODUCTION

Staging laparoscopy (SL) has become commonplace in the preoperative staging pathway for oesophagogastric (OG) cancer. SL is often performed before curative treatment to examine for macroscopic peritoneal metastases (PM) or positive peritoneal cytology (PPC). The aim of this study was to develop an objective risk scoring system to predict both PM and PPC at SL.

METHODS

A prospectively collected and maintained database of all OG cancer patients treated between 2006 and 2020 was reviewed. Univariate and multivariate analyses were performed to identify risk factors for both PM and PPC at SL. A risk score was produced for both PM and PPC, and then validated internally.

RESULTS

Among 968 patients who underwent SL, 96 (9.9%) had PM and 81 (8.4%) had PPC at SL. Tumour site (p < 0.001), computed tomography (CT) T stage (p < 0.001) and N stage (p = 0.029) were significantly associated with PM at SL (p < 0.001). Tumour site (p < 0.001), biopsy histology (p = 0.041), CT T stage (p < 0.001) and N stage (p < 0.001) were significantly associated with PPC. The risk scoring model for PM included cancer site and CT T stage. This was successfully tested on the validation set (area under the receiver operating characteristic [AUROC] = 0.730). The risk scoring model for PPC included cancer site, CT T and N stage. This was successfully tested on the validation set (AUROC = 0.773).

CONCLUSIONS

The current risk scores are valid tools with which to predict the risk PM and PPC in patients undergoing SL for OG cancer and may help to avoid subjecting patients to unnecessary SL.

[Repair of Metachronous Inguinal Metastasis from Resected Gastric Cancer by Transabdominal Preperitoneal (TAPP) Technique-A Case Report]

A 68-year-old male patient underwent laparoscopic pyloric gastrectomy(D2)in October 2015 for gastric cancer, pStage ⅠB. In August 2017, a 3 cm large abdominal wall metastasis in the left lateral abdomen was removed. In September 2019, a 2 cm tumor was found in the left inguinal region. The left inguinal area was repaired using mesh with the TAPP technique because of a large abdominal wall defect centered on the inner inguinal ring. Three and a half years after the resection, he is continuing complete response(CR)with nivolumab therapy.

Chronological Trend of Opportunistic Endoscopic Screening for Gastric Cancer and Atrophic Gastritis

BACKGROUND

Opportunistic endoscopic screening for gastric cancer was initiated in 2004 at our institute. We investigated chronological trends in gastric cancer detection rates based on individual characteristics and atrophic gastritis prevalence.

METHODS

Overall, 15,081 asymptomatic individuals aged ≥40 years without a medical history of gastric cancer underwent first-time esophagogastroduodenoscopy in our institute between February 2004 and December 2017. We retrospectively investigated individual characteristics and endoscopic diagnoses by period (early period: 2004-2007, middle period: 2008-2012, and late period: 2013-2017), clarified the long-term detection rate and the characteristics of endoscopic screening-detected gastric cancer, and evaluated the relationship between gastric cancer and atrophic gastritis.

RESULTS

Gastric cancer detection rates in the early, middle, and late periods were 1.01% (76/7,503, men/women: 4,360/3,143, average age: 59.4 years, prevalence of atrophic gastritis: 72%), 0.69% (40/5,820, men/women: 3,668/2,152, average age: 56.8 years, prevalence of atrophic gastritis: 48%), and 0.46% (8/1,758, men/women: 1,083/675, average age: 58.7 years, prevalence of atrophic gastritis: 37%), respectively. Multivariate analysis revealed that male sex (odds ratio 1.92, 95% confidence interval 1.28-2.95), age ≥75 years (2.73, 95% CI 1.32-5.05), and atrophic gastritis (C1-C3: 2.21, 1.36-3.73, O1-O3: 5.36, 3.17-9.30) were significantly associated with the incidence of gastric cancer.

CONCLUSIONS

The gastric cancer detection rate and atrophic gastritis prevalence have decreased over time. However, continuing endoscopic screening is important, especially for those at a high risk of developing gastric cancer complicated by severe atrophic gastritis.

Targeting cell surface glucose-regulated protein 94 in gastric cancer with an anti-GRP94 human monoclonal antibody

Gastric cancer (GC), a leading cause of cancer-related mortality, remains a significant challenge despite recent therapeutic advancements. In this study, we explore the potential of targeting cell surface glucose-regulated protein 94 (GRP94) with antibodies as a novel therapeutic approach for GC. Our comprehensive analysis of GRP94 expression across various cancer types, with a specific focus on GC, revealed a substantial overexpression of GRP94, highlighting its potential as a promising target. Through in vitro and in vivo efficacy assessments, as well as toxicological analyses, we found that K101.1, a fully human monoclonal antibody designed to specifically target cell surface GRP94, effectively inhibits GC growth and angiogenesis without causing in vivo toxicity. Furthermore, our findings indicate that K101.1 promotes the internalization and concurrent downregulation of cell surface GRP94 on GC cells. In conclusion, our study suggests that cell surface GRP94 may be a potential therapeutic target in GC, and that antibody-based targeting of cell surface GRP94 may be an effective strategy for inhibiting GRP94-mediated GC growth and angiogenesis. [BMB Reports 2024; 57(4): 188-193].

Association of Cholinesterase With Postoperative Pneumonia After Gastrectomy for Gastric Cancer

INTRODUCTION

Cholinesterase is a classical marker that reflects nutritional and inflammatory status. The aim of the present study was to evaluate the association between serum cholinesterase levels and postoperative infectious complications in patients undergoing gastrectomy for gastric cancer.

MATERIALS AND METHODS

This retrospective study comprised 108 patients who underwent gastrectomy for gastric cancer. We comprehensively investigated the association between clinicopathological variables and postoperative infectious complications after gastrectomy. Then patients were divided into the cholinesterase-high and -low groups to analyze their clinicopathological variables. Finally, we analyzed the types of infectious complications that were most associated with preoperative serum cholinesterase levels.

RESULTS

Twenty-six patients (24%) developed postoperative infectious complications. Multivariate analysis revealed that serum cholinesterase levels (P = 0.026) and N stage (P = 0.009) were independent risk factors for postoperative infectious complications. In particular, the incidence of pneumonia (P = 0.001) was significantly higher in the cholinesterase-low group. Age (P = 0.023), cerebrovascular comorbidities (P = 0.006), serum cholinesterase levels (P = 0.013), and total gastrectomy (P = 0.017) were identified as independent risk factors for postoperative pneumonia.

CONCLUSIONS

Preoperative serum cholinesterase levels were associated with postoperative pneumonia after gastrectomy for gastric cancer, suggesting the importance of preoperative nutritional assessment in gastric cancer surgery.

Transthoracic single-port-assisted laparoscopic gastrectomy versus laparoscopic transhiatal approach for Siewert type II adenocarcinoma of the esophagogastric junction: a single-center retrospective study

BACKGROUND

The surgical approach for patients with Siewert type II AEG remains controversial. Several studies have described a new laparoscopic radical resection approach of Siewert type II AEG through the left diaphragm. However, the technical safety and feasibility of the new surgical approach compared with the transhiatal approach have not yet been tested.

STUDY DESIGN

We retrospectively reviewed patients with AEG who underwent TSLG and LTH operations in the Guangdong Provincial Hospital of Chinese Medicine between January 2017 and April 2021. Histologically confirmed AEG and D2 lymphadenectomy with curative R0 patients were included, and patients with Siewert I/III AEG or distant metastasis were excluded. Blood loss, the amount of harvested lymph node, and complications related to surgery were evaluated.

RESULTS

A total of 99 patients with Siewert type II AEG were analyzed, 44 in the TSLG group and 55 in the LTH group. There was no difference in clinicopathological features between the two groups. The more harvested lymph node (23.33 ± 11.41 vs. 32.18 ± 12.85, p < 0.01), lower mediastinal lymph node (1.07 ± 2.08 vs. 3.25 ± 3.31, p < 0.01), and longer proximal margin length (3.08 ± 1.19 vs. 4.47 ± 0.95 cm, p < 0.01) were observed in the TSLG group. The rate of cure (R0 gastrectomy) in the TSLG group was higher than that in the LTH group (100% vs. 89.09%, p = 0.03).

CONCLUSION

The TSLG approach is associated with improved surgical views, simplified lymphatic dissection in the inferior mediastinum, and more reliable margins. TSLG surgery may be an effective addition to LTH surgery, particularly when lower mediastinal lymph node metastases are suspected.

Predicting pathologic response to neoadjuvant chemotherapy in locally advanced gastric cancer: The establishment of a spectral CT-based nomogram from prospective datasets

BACKGROUND

To establish a spectral CT-based nomogram for predicting early neoadjuvant chemotherapy (NAC) response for locally advanced gastric cancer (LAGC).

METHODS

This study prospectively recruited 222 cases (177 male and 45 female patients, 9.59 ± 9.54 years) receiving NAC and radical gastrectomy. Triple enhanced spectral CT scans were performed before NAC initiation. According to post-operative tumor regression grade (TRG), patients were classified into responders (TRG = 0 + 1) or non-responders (TRG = 2 + 3), and split into a primary (156) and validation (66) dataset at 7:3 ratio chronologically. We compared clinicopathological data, follow-up information, iodine concentration (IC), normalized ICs (nICs) in arterial/venous/delayed phases (AP/VP/DP) between responders and non-responders. Independent risk factors of response were screened by multivariable logistic regression and adopted for model construction. Model was visualized by nomograms and its capability was determined through receiver operating characteristic (ROC) curves. Log-rank survival analysis was conducted to explore associations between TRG, nomogram and patients' survival.

RESULTS

This work identified Borrmann classification, ICDP, and nICDP were independent risk factors of response outcomes. A spectral CT-based nomogram was built accordingly and achieved an area under the curve (AUC) of 0.797 (0.692-0.879) and 0.741(0.661-0.811) for the primary and validation dataset, respectively, higher than AUC of individual parameters alone. The nomogram was related to disease-free survival in the validation dataset (Hazard ratio (HR): 5.19 [1.18-12.93], P = 0.02).

CONCLUSIONS

The spectral CT-based nomogram provides an efficient tool for predicting the pathologic response outcomes of GC after NAC and disease-free survival risk stratification.

Immune Landscape of Epstein-Barr Virus-Associated Gastric Cancer: Analysis From a Western Academic Institution

INTRODUCTION

Epstein-Barr virus-associated gastric cancer (EBVaGC) may be a meaningful biomarker for potential benefit from immunotherapy. Further investigation is needed to characterize the immune landscape of EBVaGC. We assessed our institutional frequency of surgically treated EBVaGC and analyzed the immunologic biomarker profile and tumor-infiltrating lymphocyte (TIL) phenotypes of a series of EBVaGC compared to non-EBVaGC cases.

METHODS

Available tissue samples from all patients with biopsy-confirmed gastric adenocarcinoma who underwent resection with curative intent from 2012 to 2020 at our institution were collected. In situ hybridization was used to assess EBV status; multiplex immunohistochemistry was performed to assess mismatch repair status, Programmed Death-Ligand 1 (PD-L1) expression, and phenotypic characterization of TILs.

RESULTS

Sixty-eight samples were included in this study. EBVaGC was present in 3/68 (4%) patients. Among all patients, 27/68 (40%) had positive PD-L1 expression; two of three (67%) EBVaGC patients exhibited positive PD-L1 expression. Compared to non-EBVaGC, EBV-positive tumors showed 5-fold to 10-fold higher density of TILs in both tumor and stroma and substantially elevated CD8+ T cell to Tregulatory cell ratio. The memory subtypes of CD8+ and CD4+ T cells were upregulated in EBVaGC tumors and stromal tissue compared to non-EBVaGC.

CONCLUSIONS

The incidence of surgically resected EBVaGC at our center was 4%. EBVaGC tumors harbor elevated levels of TILs, including memory subtypes, within both tumor and tumor-related stroma. Robust TIL presence and upregulated PD-L1 positivity in EBVaGC may portend promising responses to immunotherapy agents. Further investigation into routine EBV testing and TIL phenotype of patients with gastric cancer to predict response to immunotherapy may be warranted.

Regulator of G protein signaling 1 is a potential target in gastric cancer and impacts tumor-associated macrophages

Regulator of G protein signaling 1 (RGS1) is closely associated with the tumor immune microenvironment and is highly expressed in various tumors and immune cells. The specific effects of RGS1 in the dynamic progression from chronic gastritis to gastric cancer have not been reported, and the role of tumor-associated macrophages (TAMs) is also unclear. In the present study, RGS1 was identified as an upregulated gene in different pathological stages ranging from chronic gastritis to gastric cancer by using Gene Expression Omnibus (GEO) screening together with pancancer analysis of The Cancer Genome Atlas and clinical prognostic analysis. The results indicated that RGS1 is highly expressed in gastric cancer and has potential prognostic value. We confirmed through in vivo experiments that RGS1 inhibited the proliferation of gastric cancer cells and promoted apoptosis, which was further corroborated by in vitro experiments. Additionally, RGS1 influenced cell migration and invasion. In our subsequent investigation of RGS1, we discovered its role in the immune response. Through analyses of single-cell and GEO database data, we confirmed its involvement in immune cell regulation, specifically TAM activation. Subsequently, we conducted in vivo and in vitro experiments to confirm the involvement of RGS1 in polarizing M1 macrophages while indirectly regulating M2 macrophages through tumor cells. In conclusion, RGS1 could be a potential target for the transformation of chronic gastritis into gastric cancer and has a measurable impact on TAMs, which warrants further in-depth research.

DR30318, a novel tri-specific T cell engager for Claudin 18.2 positive cancers immunotherapy

BACKGROUND

Claudin 18.2 (CLDN18.2) is a highly anticipated target for solid tumor therapy, especially in advanced gastric carcinoma and pancreatic carcinoma. The T cell engager targeting CLDN18.2 represents a compelling strategy for enhancing anti-cancer efficacy.

METHODS

Based on the in-house screened anti-CLDN18.2 VHH, we have developed a novel tri-specific T cell engager targeting CLDN18.2 for gastric and pancreatic cancer immunotherapy. This tri-specific antibody was designed with binding to CLDN18.2, human serum albumin (HSA) and CD3 on T cells.

RESULTS

The DR30318 demonstrated binding affinity to CLDN18.2, HSA and CD3, and exhibited T cell-dependent cellular cytotoxicity (TDCC) activity in vitro. Pharmacokinetic analysis revealed a half-life of 22.2-28.6 h in rodents and 41.8 h in cynomolgus monkeys, respectively. The administration of DR30318 resulted in a slight increase in the levels of IL-6 and C-reactive protein (CRP) in cynomolgus monkeys. Furthermore, after incubation with human PBMCs and CLDN18.2 expressing cells, DR30318 induced TDCC activity and the production of interleukin-6 (IL-6) and interferon-gamma (IFN-γ). Notably, DR30318 demonstrated significant tumor suppression effects on gastric cancer xenograft models NUGC4/hCLDN18.2 and pancreatic cancer xenograft model BxPC3/hCLDN18.2 without affecting the body weight of mice.

Investigating the role of circulating tumor cells in gastric cancer: a comprehensive systematic review and meta-analysis

Investigating the role of circulating tumor cells (CTCs) and their characteristics is still controversial in patients with gastric cancer (GC). Therefore, in this study, to provide a comprehensive review and meta-analyses of the literature on association of CTCs with gastric cancer, Scopus, Web of Science, Embase, and Medline were searched for systematic reviews and meta-analyses conducted during February 2022 using the keywords. Risk of bias, hazard ratios (HRs), and risk differences (RD) were assessed. Forty-five studies containing 3,342 GC patients from nine countries were assessed. The overall prevalence of CTC in GC was 69.37% (60.27, 77.78). The pooled result showed that increased mortality in GC patients was significantly associated with positive CTCs, poor overall survival (HR = 2.73, 95%CI 2.34-3.24, p < 0.001), and progression-free survival rate (HR = 2.78, 95%CI 2.01-3.85, p < 0.001). Subgroup analyses regarding markers, detection methods, treatment type, presence of distance metastasis, presence of lymph node metastasis, and overall risk of bias showed significant associations between the groups in terms of the incidence rates of CTCs, OS, and PFS. In addition, the results of risk differences based on sampling time showed that the use of the cell search method (RD: - 0.19, 95%CI (- 0.28, - 0.10), p < 0.001), epithelial marker (RD: - 0.12, 95%CI (- 0.25, 0.00), p 0.05) and mesenchymal markers (RD: - 0.35, 95%CI (- 0.57, - 0.13), p 0.002) before the treatment might have a higher diagnostic power to identify CTCs and also chemotherapy treatment (RD: - 0.17, 95%CI (- 0.31, - 0.03), p 0.016) could significantly reduce the number of CTCs after the treatment. We also found that the risk differences between the clinical early and advanced stages were not statistically significant (RD: - 0.10, 95%CI (- 0.23, 0.02), P 0.105). Also, in the Lauren classification, the incidence of CTC in the diffuse type (RD: - 0.19, 95%CI (- 0.37, - 0.01), P0.045) was higher than that in the intestinal type. Meta-regression analysis showed that baseline characteristics were not associated with the detection of CTCs in GC patients. According to our systematic review and meta-analysis, CTCs identification may be suggested as a diagnostic technique for gastric cancer screening, and the outcomes of CTC detection may also be utilized in the future to create personalized medicine programs.

Gastritis cystica profunda in an unoperated stomach mimicking a pyloric submucosal tumor and causing anorexia: A case report and literature review

BACKGROUND

Gastritis cystica profunda (GCP), commonly observed in remnant gastric anastomosis, is associated with developing gastric cancer.

CASE

This case report describes a patient with GCP in a previously unoperated stomach that mimicked a pyloric submucosal tumor and caused anorexia, which is rare in clinical practice.

PATIENT CONCERNS

A 72-year-old woman presented with loss of appetite and weight.

DIAGNOSES

Gastroscopy detected a 20 mm diameter submucosal tumor near the pylorus. Computed tomography and magnetic resonance imaging identified a cystic lesion, unlike a usual submucosal tumor in the stomach. The diagnosis was difficult, even with endoscopic ultrasound-guided fine-needle aspiration.

INTERVENTIONS

Surgery was performed for diagnosis and treatment. The lesion was resected using a submucosal dissection technique after an incision of the gastric wall during open laparotomy. Histopathological examination confirmed the diagnosis of GCP and revealed no dysplasia or cancer.

OUTCOMES

Anorexia resolved after the surgery. Residual or recurrent lesions were not detected during follow-up examinations performed 1 year after surgery.

LESSONS

GCP occurring in a previously unoperated stomach as a macroscopic lesion like a submucosal tumor causing some symptoms is rare. GCP is associated with a risk of developing cancer. Therefore, careful evaluation and management during treatment are required.

A prospective phase II clinical trial of total neoadjuvant therapy for locally advanced gastric cancer and gastroesophageal junction adenocarcinoma

To investigate the safety and efficacy of the neoadjuvant chemoradiotherapy (NCRT) followed by neoadjuvant consolidation chemotherapy (NCCT) and surgery for locally advanced gastric cancer (GC) or gastroesophageal junction (GEJ) adenocarcinoma. Patients diagnosed as locally advanced GC or Siewert II/III GEJ adenocarcinoma with clinical stage T3-4 and/or N positive were prospectively enrolled. Patients underwent NCRT (45 Gy/25 fractions) with concurrent S-1, followed by NCCT (4 to 6 cycles of the SOX regimen) 2 to 4 weeks after NCRT. Gastric cancer radical resection with D2 lymph node dissection was performed 4 to 6 weeks after the total neoadjuvant therapy. The study was conducted from November 2019 to January 2023, enrolling a total of 46 patients. During the NCRT, all patients completed the treatment without dose reduction or delay. During the NCCT, 32 patients (69.6%) completed at least 4 cycles of chemotherapy. Grade 3 or higher adverse events in NCRT (5 cases) were non-hematological. During the course of NCCT, a notable occurrence of hematological toxicities was observed, with grade 3 or higher leukopenia (9.7%) and thrombocytopenia (12.2%) being experienced. A total of 28 patients (60.9%) underwent surgery, achieving R0 resection in all cases. A significant proportion of cases (71.4%) exhibited pathological downstaging to ypT0-2, while 10 patients (35.7%) demonstrated a pathologic complete response (pCR). The total neoadjuvant therapy comprising NCRT followed by NCCT and surgery demonstrates a low severe adverse reactions and promising efficacy, which could be considered as a viable treatment for locally advanced GC or GEJ adenocarcinoma.Trial registration: Clinicaltrials.gov (registration number: NCT04062058); the full date of first trial registration was 20/08/2019.

LncRNA SNHG26 promotes gastric cancer progression and metastasis by inducing c-Myc protein translation and an energy metabolism positive feedback loop

Metastasis is a bottleneck in cancer treatment. Studies have shown the pivotal roles of long noncoding RNAs (lncRNAs) in regulating cancer metastasis; however, our understanding of lncRNAs in gastric cancer (GC) remains limited. RNA-seq was performed on metastasis-inclined GC tissues to uncover metastasis-associated lncRNAs, revealing upregulated small nucleolar RNA host gene 26 (SNHG26) expression, which predicted poor GC patient prognosis. Functional experiments revealed that SNHG26 promoted cellular epithelial-mesenchymal transition and proliferation in vitro and in vivo. Mechanistically, SNHG26 was found to interact with nucleolin (NCL), thereby modulating c-Myc expression by increasing its translation, and in turn promoting energy metabolism via hexokinase 2 (HK2), which facilitates GC malignancy. The increase in energy metabolism supplies sufficient energy to promote c-Myc translation and expression, forming a positive feedback loop. In addition, metabolic and translation inhibitors can block this loop, thus inhibiting cell proliferation and mobility, indicating potential therapeutic prospects in GC.

KIF3C: an emerging biomarker with prognostic and immune implications across pan-cancer types and its experiment validation in gastric cancer

Kinesin Family Member 3C (KIF3C) assumes a crucial role in various biological processes of specific human cancers. Nevertheless, there exists a paucity of systematic assessments pertaining to the contribution of KIF3C in human malignancies. We conducted an extensive analysis of KIF3C, covering its expression profile, prognostic relevance, molecular function, tumor immunity, and drug sensitivity. Functional enrichment analysis was also carried out. In addition, we conducted in vitro experiments to substantiate the role of KIF3C in gastric cancer (GC). KIF3C expression demonstrated consistent elevation in various tumors compared to their corresponding normal tissues. We further unveiled that heightened KIF3C expression served as a prognostic indicator, and its elevated levels correlated with unfavorable clinical outcomes, encompassing reduced OS, DSS, and PFS in several cancer types. Notably, KIF3C expression exhibited positive associations with the pathological stages of several cancers. Moreover, KIF3C demonstrated varying relationships with the infiltration of various distinct immune cell types in gastric cancer. Functional analysis outcomes indicated that KIF3C played a role in the PI3K-AKT signaling pathway. Drug sensitivity unveiled a positive relationship between KIF3C in gastric cancer and the IC50 values of the majority of identified anti-cancer drugs. Additionally, KIF3C knockdown reduced the proliferation, migration, and invasion capabilities, increased apoptosis, and led to alterations in the cell cycle of gastric cancer cells. Our research has revealed the significant and functional role of KIF3C as a tumorigenic gene in diverse cancer types. These findings indicate that KIF3C may serve as a promising target for the treatment of gastric cancer.

The necroptosis-related signature and tumor microenvironment immune characteristics associated with clinical prognosis and drug sensitivity analysis in stomach adenocarcinoma

PURPOSE

Necroptosis plays an important role in the tumorigenesis, development, metastasis, and drug resistance of malignant tumors. This study explored the new model for assessing stomach adenocarcinoma (STAD) prognosis and immunotherapy by combining long noncoding RNAs associated with necroptosis.

METHODS

Patient clinical data and STAD gene expression profiles were curated from The Cancer Genome Atlas (TCGA). Immune-related genes were sourced from a specialized molecular database. Perl software and R software were used for data processing and analysis. Necroptosis-related lncRNAs in STAD were pinpointed via R's correlation algorithms. These lncRNAs, in conjunction with clinical data, informed the construction of a prognostic lncRNA-associated risk score model using univariate and multivariate Cox regression analyses. The model's prognostic capacity was evaluated by Kaplan-Meier survival curves and validated as an independent prognostic variable. Further, a nomogram incorporating this model with clinical parameters was developed, offering refined individual survival predictions. Subsequent analyses of immune infiltration and chemosensitivity within necroptosis-related lncRNA clusters utilized an arsenal of bioinformatic tools, culminating in RT-PCR validation of lncRNA expression.

RESULTS

Through rigorous Cox regression, 21 lncRNAs were implicated in the risk score model. Stratification by median risk scores delineated patients into high- and low-risk cohorts, with the latter demonstrating superior prognostic outcomes. The risk model was corroborated as an independent prognostic indicator for STAD. The integrative nomogram displayed high concordance between predicted and observed survival rates, as evidenced by calibration curves. Differential immune infiltration in risk-defined groups was illuminated by the single sample GSEA (ssGSEA), indicating pronounced immune presence in higher-risk patients. Tumor microenvironment (TME) analysis showed that cluster-C3 had the highest score in the analysis of the three TMEs. Through the differential analysis of immune checkpoints, it was found that almost all immune checkpoint-related genes were expressed differently in various tumor clusters. Among them, CD44 expression was the highest. By comparing all drug sensitivities, we screened out 29 drugs with differences in drug sensitivity across different clusters. Risk score gene expression identification results showed that these lncRNAs were abnormally expressed in gastric cancer cell lines.

CONCLUSIONS

This investigation provides a robust methodological advance in prognosticating and personalizing immunotherapy for STAD, leveraging quantitatively derived tumor cluster risk scores. It posits the use of necroptosis-related lncRNAs as pivotal molecular beacons for guiding therapeutic strategies and enhancing clinical outcomes in STAD.

Analysis of endoscopic and pathological features of 6961 cases of gastric cancer

Gastric cancer (GC) stage and tissue differentiation affect treatment efficacy and prognosis, highlighting the importance of understanding the risk factors that affect these parameters. Therefore, this study analyzed risk factors affecting the GC stage and differentiation and the relationships between the cancer site and the sex and age of the patient. We collected clinical data from 6961 patients with GC, including sex, age, endoscopic lesion location, and pathological differentiation. Patients were grouped based on GC stage (early or advanced), differentiation (well or poorly differentiated), and lesion site (upper stomach [cardia and fundus], middle stomach [gastric body], and lower stomach [gastric antrum]). Differences in sex, age, location, stage, and degree of differentiation were assessed based on these groupings. Univariate analysis revealed that the disease location and differentiation significantly differed based on the GC stage (P < 0.05), whereas sex, age, site, and stage significantly differed based on GC differentiation (P < 0.05). A multivariate analysis confirmed these factors as independent risk factors affecting GC. Moreover, lesion sites significantly differed between sexes (P < 0.05) and among age groups (P < 0.05). Although the effects of family history, lifestyle, and Helicobacter pylori infection status of the patients were not considered, this single-center retrospective study established independent risk factors for GC.Trial registration ChiCTR2200061989.

The Role of Epstein-Barr Virus (EBV) Infected Gastric Cancer in Increasing microRNA124 (miR-124) Promoter Methylation and Enhancer of Zeste Homolog 2 (EZH2) Gene Expression

The tumor suppressor microRNAs, miR-21, miR-124, and miR-494, participate in the controlling several cellular processes. To assess target miRNAs promoter methylation levels, we investigated 304 pairs of gastric cancer (GC) tissues and non-tumor tissues. We used a commercial real-time polymerase chain reaction (RT-PCR) for Epstein-Barr virus (EBV) and Helicobacter pylori kit to detect EBV and H. pylori DNA in GC tissues. After finding hypermethylation in the promoter of the miR-124 gene, we evaluated its expression level using quantitative PCR (qPCR). Bioinformatics analysis confirmed miR-124 as a target of enhancer of Zeste homolog 2 (EZH2). Additionally, qPCR confirmed the association between EZH2 and miR-124. EBV and H. pylori DNA were detected in 9.5% and 15.1% of GC patients, respectively. Our findings also revealed significant differences in the miR-124 methylation levels among EBV-infected GC patients, H. pylori infected GC patients, GC patients without EBV and H. pylori infection, and non-tumor tissue. Bioinformatics and qPCR assays suggested an inverse relationship between the expression levels of EZH2 and miR-124 in EBV-infected GC patients. Our data revealed hypermethylation of the miR-124 promoter and significant reduction in its expression in EBV-infected GC tissues. It is possible that miR-124 may target EZH2 by binding to the 3'-UTR of the EZH2 gene, thus potentially contributing to the development of EBV-infected GC.

RACGAP1 drives proliferation, migration and invasion and suppresses autophagy of gastric cancer cells via inhibiting SIRT1/Mfn2

Objective

Gastric cancer is the most frequent gastrointestinal malignancy with a poor prognosis. Rac GTPase activation protein 1 (RACGAP1) is a novel tumor promotor, whose detailed effect on gastric cancer remains to be further elucidated. Hence, this study identifies the action of RACGAP1 on gastric cancer and investigates the potential mechanism.

Methods

RACGAP1 expression in gastric cancer was analyzed based on the data of The Cancer Genome Atlas (TCGA) database. Cell proliferation was measured by CCK-8 and colony formation assay. Cell migration and invasion were evaluated by transwell assay. Cell apoptosis was assessed by flow cytometry. Cell autophagy was evaluated via determining LC3.

Results

RACGAP1 presented at high level in gastric cancer cells. Overexpressed RACGAP1 potentiated gastric cancer cell proliferation, migration, and invasion. Besides, silenced RACGAP1 induced cell apoptosis and autophagy. Furthermore, RACGAP1 suppressed the expression of SIRT1 and Mfn2.

Conclusion

RACGAP1 was overexpressed in gastric cancer. RACGAP1 potentiated aggressive behaviors of gastric cancer, and suppressed cell apoptosis and autophagy via modulating SIRT1/Mfn2. RACGAP1 may be a valuable target in the treatment of gastric cancer.