Exosomal LINC00853 promotes progression of gastric cancer via the MAP17/PDZK1/AKT signaling pathway.

Although rare, there is ongoing research into biomarkers that predict the onset and recurrence of gastric cancer, particularly focusing on substances found in exosomes. Long non-coding RNAs (lncRNAs) have garnered attention for their potential in diagnosing gastric cancer. This study investigates the role of lncRNAs in gastric cancer, focusing on their presence in exosomes as potential biomarkers for the disease's onset and recurrence. We utilized the ArrayStar Human LncRNA array 2.0 to analyze lncRNA expression in tissues from early-stage gastric cancer patients. Our analysis highlighted LINC00853, which was significantly upregulated in cancer tissues and implicated in promoting epithelial-mesenchymal transition via the MAP17/PDZK1/AKT pathway. Functional studies on AGS and MKN74 gastric cancer cell lines demonstrated that LINC00853 facilitates cell proliferation, invasion, and migration. Additionally, RNA immunoprecipitation and electrophoretic mobility shift assays confirmed LINC00853 interaction with MAP17. Importantly, LINC00853 was also detected in exosomes from both patient samples and cell lines, and its downregulation led to decreased tumorigenicity in AGS cells. These findings suggest that both cellular and exosomal LINC00853 contribute to gastric cancer pathogenesis and may serve as valuable biomarkers for the disease.

Impact of Coronavirus Disease 2019 on Gastric Cancer Diagnosis and Stage: A Single-Institute Study in South Korea.

PURPOSE: Gastric cancer (GC) is among the most prevalent and fatal cancers worldwide. National cancer screening programs in countries with high incidences of this disease provide medical aid beneficiaries with free-of-charge screening involving upper endoscopy to detect early-stage GC. However, the coronavirus disease 2019 (COVID-19) pandemic has caused major disruptions to routine healthcare access. Thus, this study aimed to assess the impact of COVID-19 on the diagnosis, overall incidence, and stage distribution of GC. MATERIALS AND METHODS: We identified patients in our hospital cancer registry who were diagnosed with GC between January 2018 and December 2021 and compared the cancer stage at diagnosis before and during the COVID-19 pandemic. Subgroup analyses were conducted according to age and sex. The years 2018 and 2019 were defined as the "before COVID" period, and the years 2020 and 2021 as the "during COVID" period. RESULTS: Overall, 10,875 patients were evaluated; 6,535 and 4,340 patients were diagnosed before and during the COVID-19 period, respectively. The number of diagnoses was lower during the COVID-19 pandemic (189 patients/month vs. 264 patients/month) than before it. Notably, the proportion of patients with stages 3 or 4 GC in 2021 was higher among men and patients aged ≥40 years. CONCLUSIONS: During the COVID-19 pandemic, the overall number of GC diagnoses decreased significantly in a single institute. Moreover, GCs were in more advanced stages at the time of diagnosis. Further studies are required to elucidate the relationship between the COVID-19 pandemic and the delay in the detection of GC worldwide.

Sample Collection Methods in Upper Gastrointestinal Research.

In recent years, significant translational research advances have been made in the upper gastrointestinal (GI) research field. Endoscopic evaluation is a reasonable option for acquiring upper GI tissue for research purposes because it has minimal risk and can be applied to unresectable gastric cancer. The optimal number of biopsy samples and sample storage is crucial and might influence results. Furthermore, the methods for sample acquisition can be applied differently according to the research purpose; however, there have been few reports on methods for sample collection from endoscopic biopsies. In this review, we suggested a protocol for collecting study samples for upper GI research, including microbiome, DNA, RNA, protein, single-cell RNA sequencing, and organoid culture, through a comprehensive literature review. For microbiome analysis, one or two pieces of biopsied material obtained using standard endoscopic forceps may be sufficient. Additionally, 5 mL of gastric fluid and 3-4 mL of saliva is recommended for microbiome analyses. At least one gastric biopsy tissue is necessary for most DNA or RNA analyses, while proteomics analysis may require at least 2-3 biopsy tissues. Single cell-RNA sequencing requires at least 3-5 tissues and additional 1-2 tissues, if possible. For successful organoid culture, multiple sampling is necessary to improve the quality of specimens.

A single arm phase Ib/II trial of first-line pembrolizumab, trastuzumab and chemotherapy for advanced HER2-positive gastric cancer.

In this multi-center phase II trial, we evaluated the efficacy and safety of a quadruplet regimen (pembrolizumab, trastuzumab, and doublet chemotherapy) as first-line therapy for unresectable or metastatic human epidermal growth factor receptor 2 (HER2)-positive advanced gastric cancer (AGC) (NCT02901301). The primary endpoints were recommended phase 2 dose (RP2D) for phase Ib and objective response rate (ORR) for phase II. The secondary endpoints included progression-free survival (PFS), overall survival (OS), duration of response, time to response and safety. Without dose-limiting or unexpected toxicities, the starting dose in the phase Ib trial was selected as RP2D. In 43 patients, the primary endpoint was achieved: the objective response rate was 76.7% (95% confidence interval [CI]: 61.4-88.2), with complete and partial responses in 14% and 62.8% of patients, respectively. The median progression-free survival, overall survival, and duration of response were 8.6 months, 19.3 months, and 10.8 months, respectively. No patients discontinued pembrolizumab because of immune-related adverse events. Programmed death ligand-1 status was not related to survival. Post hoc analyses of pretreatment tumor specimens via targeted sequencing indicated that ERBB2 amplification, RTK/RAS pathway alterations, and high neoantigen load corrected by HLA-B were positively related to survival. The current quadruplet regimen shows durable efficacy and safety for patients with HER2-positive AGC.

Probe-Based Confocal Laser Endomicroscopy versus White-Light Endoscopy with Narrow-Band Imaging for Predicting and Collecting Residual Cancer Tissue in Patients with Gastric Cancer Receiving Chemotherapy.

In cases of progression despite chemotherapy, collecting gastric cancer (GC) tissues might be helpful for molecular biology research or the development of new target drugs for treating cases that are refractory to chemotherapy. Chemotherapy, however, may reduce or alter the distribution of GC tissue on the surface, making the detection of GC tissue during upper endoscopy challenging. Probe-based confocal laser endomicroscopy (pCLE) is a new technology that enables histological diagnosis by magnifying the mucous membrane to a microscopic level. Here, we evaluated whether pCLE could increase the yield of endoscopic biopsy for GC compared to white-light endoscopy (WLE) with magnifying narrow-band imaging (M-NBI) in GC patients receiving chemotherapy with its powerful imaging technique. Patients underwent WLE/M-NBI and pCLE for the detection of residual GC for the purpose of response evaluation or clinical trial registration. After WLE/M-NBI and pCLE, each residual GC lesion was biopsied for histological analysis. A total of 23 patients were enrolled between January 2018 and June 2020. Overall, pCLE showed significantly higher sensitivity and negative predictive value than WLE/M-NBI. The accuracy of pCLE was superior to that of WLE/M-NBI. Moreover, pCLE showed better predictive ability for residual GC than WLE/M-NBI, while WLE/M-NBI and pCLE showed inconsistent results. pCLE diagnosed residual GC more accurately than WLE/M-NBI, which resulted in an increased number of GC tissues collected during the endoscopic biopsy.

Machine Learning Improves the Prediction Rate of Non-Curative Resection of Endoscopic Submucosal Dissection in Patients with Early Gastric Cancer.

Non-curative resection (NCR) of early gastric cancer (EGC) after endoscopic submucosal dissection (ESD) can increase the burden of additional treatment and medical expenses. We aimed to develop a machine-learning (ML)-based NCR prediction model for EGC prior to ESD. We obtained data from 4927 patients with EGC who underwent ESD between January 2006 and February 2020. Ten clinicopathological characteristics were selected using extreme gradient boosting (XGBoost) and were used to develop a ML-based model. Dataset was divided into the training and internal validation sets and verified using an external validation set. Sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC) were evaluated. The performance of each model was compared by using the Delong test. A total of 1100 (22.1%) patients were identified as being treated non-curatively with ESD. Seven ML-based NCR prediction models were developed. The performance of NCR prediction was highest in the XGBoost model (AUROC, 0.851; 95% confidence interval, 0.837-0.864). When we compared the prediction performance by the Delong test, XGBoost (p = 0.02) and support vector machine (p = 0.02) models showed a significantly higher performance among the NCR prediction models. We developed an ML model capable of accurately predicting the NCR of EGC before ESD. This ML model can provide useful information for decision-making regarding the appropriate treatment of EGC before ESD.

2020 Seoul Consensus on the Diagnosis and Management of Gastroesophageal Reflux Disease.

Gastroesophageal reflux disease (GERD) is a condition in which gastric contents regurgitate into the esophagus or beyond, resulting in either troublesome symptoms or complications. GERD is heterogeneous in terms of varied manifestations, test findings, and treatment responsiveness. GERD diagnosis can be established with symptomatology, pathology, or physiology. Recently the Lyon consensus defined the "proven GERD" with concrete evidence for reflux, including advanced grade erosive esophagitis (Los Angeles classification grades C and or D esophagitis), long-segment Barrett's mucosa or peptic strictures on endoscopy or distal esophageal acid exposure time > 6% on 24-hour ambulatory pH-impedance monitoring. However, some Asian researchers have different opinions on whether the same standards should be applied to the Asian population. The prevalence of GERD is increasing in Asia. The present evidence-based guidelines were developed using a systematic review and meta-analysis approach. In GERD with typical symptoms, a proton pump inhibitor test can be recommended as a sensitive, cost-effective, and practical test for GERD diagnosis. Based on a meta-analysis of 19 estimated acid-exposure time values in Asians, the reference range upper limit for esophageal acid exposure time was 3.2% (95% confidence interval, 2.7-3.9%) in the Asian countries. Esophageal manometry and novel impedance measurements, including mucosal impedance and a post-reflux swallow-induced peristaltic wave, are promising in discrimination of GERD among different reflux phenotypes, thus increasing its diagnostic yield. We also propose a long-term strategy of evidence-based GERD treatment with proton pump inhibitors and other drugs.

Incidence and treatment outcomes of leakage after gastrectomy for gastric cancer: Experience of 14,075 patients from a large volume centre.

INTRODUCTION: Leakage is a serious and potentially fatal complication of gastrectomy for gastric cancer. However, comprehensive reports regarding leakage after gastrectomy remain limited. We aimed to evaluate the incidence and treatment outcomes of leakage after gastrectomy for cancer. METHODS: We reviewed the prospectively collected data of 14,075 Patients who underwent gastrectomy for gastric cancer between 2005 and 2017. Outcomes included incidence, risk factors of leakage, and leakage treatment outcomes. RESULTS: The median day of leakage detection was postoperative day 7 (range 1-29days). The overall leakage incidence was 1.51% (213/14,075), and the most frequent location was the oesophagojejunostomy (2.07%). Leakage after total gastrectomy was more frequent with minimally invasive surgery (open:1.64%, laparoscopic:3.56%, robotic:5.83%; P < 0.001). Leakage incidence was higher in the surgeon's initial 100 cases than in later cases (2.4 vs. 1.3%; P < 0.001), especially with minimally invasive surgery. Early leakage (within 4 days of surgery) occurred more often after minimally invasive surgery (open:12.7%, laparoscopic:35.4%, robotic:29.0%; P = 0.006). The success rate for initial treatment of leakage was 70.4% (150/213). Surgery after initial treatment failure demonstrated a higher success rate for early leakage than for late leakage (80.0 vs. 22.2%). Among 213 patients who experienced leakage, fifteen patients (7.0%) died, and leakage-related mortality accounted for 38.5% (15/39) of all surgery-related mortality after gastrectomy. CONCLUSIONS: Leakage after gastric cancer surgery is associated with high mortality. Improved surgeon experience using minimally invasive techniques is required to reduce the risk of leakage. Surgery is an effective treatment for early leakage, although further studies are needed to establish the most appropriate treatment strategies.

Prediction model for bleeding after endoscopic submucosal dissection of gastric neoplasms from a high-volume center.

BACKGROUND AND AIM: Bleeding after endoscopic submucosal dissection (ESD) is a main adverse event. To date, although there have been several studies about risk factors for post-ESD bleeding, there has been few predictive model for post-ESD bleeding with large volume cases. We aimed to design a prediction model for post-ESD bleeding using a classification tree model. METHODS: We analyzed a prospectively established cohort of patients with gastric neoplasms treated with ESD from 2007 to 2016. Baseline characteristics were collected for a total of 5080 patients, and the bleeding risk was estimated using variable statistical methods such as logistic regression, AdaBoost, and random forest. To investigate how bleeding was affected by independent predictors, the classification and regression tree (CART) method was used. The prediction tree developed for the cohort was internally validated. RESULTS: Post-ESD bleeding occurred in 262 of 5080 patients (5.1%). In multivariate logistic regression, ongoing antithrombotic use during the procedure, cancer pathology, and piecemeal resection were significant risk factors for post-ESD bleeding. In the CART model, the decisive variables were ongoing antithrombotic agent use, resected specimen size ≥49 mm, and patient age <62 years. The CART model accuracy was 94.9%, and the cross-validation accuracy was 94.8%. CONCLUSIONS: We developed a simple and easy-to-apply predictive tree model based on three risk factors that could help endoscopists identify patients at a high risk of bleeding. This model will enable clinicians to establish precise management strategies for patients at a high risk of bleeding and to prevent post-ESD bleeding.

HOTAIR Induces Methylation of PCDH10, a Tumor Suppressor Gene, by Regulating DNMT1 and Sponging with miR-148b in Gastric Adenocarcinoma.

PURPOSE: HOX transcript antisense intergenic RNA (HOTAIR), as a long non-coding RNA, has been reported to regulate carcinogenesis by epigenetic mechanism in various cancers. Protocadherin 10 (PCDH10) is one of the well-known tumor suppressor genes, and is frequently methylated in gastric cancers (GC). We aimed to investigate the detailed pathway of how HOTAIR contributes to the target gene in gastric carcinogenesis. MATERIALS AND METHODS: We investigated the mechanism of HOTAIR on carcinogenesis and metastasis of GC. Methylation-specific PCR was performed to identify the interaction between HOTAIR and PCDH10. In addition, we investigated the interaction between miR-148b and HOTAIR by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. RESULTS: The expression of HOTAIR was significantly upregulated in GC tissues (p<0.05) and GC cell lines (p<0.01), while PCDH10 was downregulated in GC tissues (p<0.05). The knockdown of HOTAIR (si-HOTAIR1 and 2) significantly upregulated the mRNA/protein expression of PCDH10 and reduced the methylation of PCDH10 compared to the control in MKN 28 and MKN 74. Si-HOTAIR1 and 2 significantly reduced DNA methyltransferase 1 (DNMT1) expression, and overexpression of HOTAIR increased DNMT1 expression. In RIP, we found that miR-148b interacted with HOTAIR. Si-HOTAIRs increased miR-148b expression, and miR-148b mimic inversely reduced HOTAIR expression. Si-HOTAIRs and miR-148b mimic reduced DNMT1 expression and increased PCDH10 expression compared to the control. CONCLUSION: This study demonstrated that HOTAIR interacts with miR-148b and DNMT1, eventually leading to PCDH10 methylation, which contributes to the progression of GC. Our findings provide a better understanding for detailed pathway of HOTAIR in epigenetic mechanism of GC.

Long-Term Outcomes and Prognostic Factors of Superficial Esophageal Cancer in Patients Aged ≥ 65 Years.

BACKGROUND: The number of elderly patients with superficial esophageal cancer (SEC) is increasing. We aimed to evaluate the clinical outcomes and prognostic factors of overall survival (OS) in elderly patients undergoing endoscopic submucosal dissection (ESD) or surgical resection for SEC. METHODS: Between January 2001 and May 2020, 290 patients aged ≥65 years who underwent ESD or surgical resection for SEC were evaluated. Their clinical outcomes and prognosis were assessed, and independent risk factors for OS were identified. RESULTS: The mean patient age (269 men and 21 women) was 70.9 years (range 65-90 years). En bloc, R0, and curative resections were achieved in 94.5%, 90.0%, and 73.4% of the patients, respectively. During the follow-up [mean: 54.6 months (range: 1-210 months)], 79 patients died. The 3-, 5-, and 10-year OS rates were 82.5, 73.1, and 59.7%, respectively. In multivariate analysis, cancer history of the other organs, American Society of Anesthesiologists performance status, and presence of lymphovascular involvement (hazard ratio = 1.852, 1.656, and 1.943, respectively; all P < 0.05) were independent risk factors for poor OS. The high-risk group (≥2 risk factors) showed a significantly lower OS than the low-risk group (≤ 1 risk factor) (P < 0.001). CONCLUSIONS: The three risk factors could be useful in predicting the long-term prognosis of elderly patients with SEC.

Comparison of the Efficacy of Polaprezinc Plus Proton Pump Inhibitor and Rebamipide Plus Proton Pump Inhibitor Treatments for Endoscopic Submucosal Dissection-induced Ulcers.

GOALS: We assessed the efficacy of polaprezinc plus proton pump inhibitor (PPI) treatment for endoscopic submucosal dissection (ESD)-induced ulcer healing compared with rebamipide plus PPI treatment. BACKGROUND: ESD has been widely used as a local treatment option that cures gastric neoplasms. However, it causes large and deep artificial ulcers, and there are no guidelines with regard to the optimal treatment durations and drug regimens for ESD-induced ulcers. Polaprezinc is effective for promoting ulcer healing and helps enhance the quality of ulcer healing. STUDY: Two hundred ten patients with ESD-induced ulcers were randomly allocated to treatment with polaprezinc (150 mg/d) plus pantoprazole (40 mg/d) or treatment with rebamipide (300 mg/d) plus pantoprazole (40 mg/d). We evaluated the ulcer healing rate and condition of the ulcer at 4 weeks after dissection. The χ2 or Fisher exact test and the Student t test were used. RESULTS: The ulcer healing rates at 4 weeks after dissection in the polaprezinc plus pantoprazole treatment group were not inferior compared with those in the rebamipide plus pantoprazole treatment group, both in the intention-to-treat analysis (90.3% and 91.4%, respectively, P=0.523) and per-protocol analysis (89.9% and 91.1%, respectively, P=0.531). The short procedure time was an independent predictive factor for a high ulcer healing rate (odds ratio: 0.975; 95% confidence interval: 0.958-0.993; P=0.006). CONCLUSION: The polaprezinc plus PPI treatment showed noninferiority to rebamipide plus PPI treatment in the ulcer healing rate at 4 weeks after ESD.

Long-Term Outcomes and Prognostic Factors of Endoscopic Submucosal Dissection for Early Gastric Cancer in Patients Aged ≥75 Years.

BACKGROUND AND AIMS: The number of elderly patients with early gastric cancer (EGC) who meet the indications for endoscopic submucosal dissection (ESD) is increasing. We aimed to evaluate the clinical outcomes and prognostic factors of overall survival (OS) in elderly patients undergoing ESD for EGC. METHODS: Between January 2006 and December 2018, 439 patients aged ≥75 years who underwent ESD for EGC were analyzed. The clinical outcomes and prognosis were evaluated, and independent risk factors for OS were identified. RESULTS: The mean patient (302 men, 137 women) age was 78.3 (range 75-92) years. En bloc, R0, and curative resections were achieved in 96.8%, 90.7%, and 75.6%, respectively, without severe adverse events. During the follow-up (median 54.2 (range 4.0-159.6) months), 86 patients died (three of gastric cancer). The 3-, 5-, and 10-year OS was 91.2%, 83.5%, and 54.5%, respectively, and the 3-, 5-, and 10-year cancer related survival rate were 99.7%, 99.1% and 97.5%, respectively. In multivariate analysis, smoking, history of cancer of other organs, NLR > 1.6, Charlson comorbidity index ≥ 3, and presence of lymphovascular invasion (hazard ratio = 3.96, 1.78, 1.83, 1.83, and 2.63, respectively, all p < 0.05) were independent five risk factors for poor OS. The high-risk group (≥3 risk factors) showed a significantly lower OS than the low-risk group (<2 risk factors) (p < 0.001). CONCLUSIONS: The five factors could be useful in predicting the long-term prognosis of elderly ESD patients or deciding the therapeutic approaches in case of non-curative resection.

LUCAT1 Epigenetically Downregulates the Tumor Suppressor Genes CXXC4 and SFRP2 in Gastric Cancer.

PURPOSE: The mechanisms of Wnt/ß-catenin pathway signaling and abnormal expression of tumor suppressor genes is not well known in gastric cancer (GC). Long non-coding RNA (lncRNA) has recently been identified as a possible link therein. In this study, we investigated the role of lung cancer associated transcript 1 (LUCAT1) in GC. MATERIALS AND METHODS: The expression of LUCAT1 in GC cell lines and 100 tissue samples was examined by qRT-PCR. Two different siRNAs were used for knockdown of LUCAT1 expression. Cell viability was assessed by MTT assay. To analyze metastasis, scratch wound-healing assay, a Matrigel invasion assay, and colony formation assay were performed. Apoptosis was analyzed by PI/Annexin-V staining. To check the methylation status in tumor suppressor genes, methylation-specific PCR was carried out. Western blot was performed to detect epithelial-mesenchymal transition and apoptosis markers upon silencing of LUCAT1 (siLUCAT1). RESULTS: LUCAT1 expression in GC cell lines and tissues was significantly elevated, compared to that in normal gastric cells and adjacent non-tumor tissues (p<0.001). Two different siRNAs for LUCAT1 reduced cell proliferation, invasion, and migration, compared to siCT (p<0.05), and these reductions were restored by pcDNA-LUCAT1 (p<0.05). siLUCAT1 elicited upregulation of the expression of CXXC4 and SFRP2. The expression of H3K27me3 was reduced by siLUCAT1, and this reduction was correlated with methylation of CXXC4 and SFRP2. Inhibition of LUCAT1 up-regulated EZH2 expression and resulted in demethylation of CXXC4 and SFRP2 through the Wnt/ß-catenin signaling pathway. CONCLUSION: We concluded that LUCAT1 induces methylation of CXXC4 and SFRP2, thereby regulating Wnt/ß-catenin signaling in GC.

Efficacy of Endoscopic Vacuum-Assisted Closure Treatment for Postoperative Anastomotic Leak in Gastric Cancer.

Background/Aims: Endoscopic vacuum-assisted closure (EVAC) has been attempted as new nonsurgical treatment for anastomotic leakage. We aimed to evaluate the clinical outcomes of EVAC and compare its efficacy with the self-expandable metallic stent (SEMS) for postgastrectomy leakage. Methods: Between January 2007 and February 2018, 39 patients underwent endoscopic treatment for anastomotic leakage after gastric cancer surgery. Of them, 28 patients were treated with SEMS, seven with EVAC after SEMS failure, and four with EVAC. We retrospectively compared the clinical characteristics and therapeutic outcomes between EVAC (n=11) and SEMS (n=28). Results: The median followup duration was 17 months (interquartile range, 9 to 26 months) in both groups. In comparison of clinical characteristics between two groups, only the median size of the leak was larger in the EVAC group than in the SEMS group (2.1 cm vs 1.0 cm; p<0.001). All EVAC cases healed successfully; however, two cases (7.1%) failed to heal in the SEMS group. Anastomotic stricture occurred one case (9.1%) in EVAC and four cases (14.3%) in SEMS within 1 year after endoscopic treatment. The median treatment duration of EVAC was shorter than that of SEMS (15 days vs 36 days; p<0.001). Median weight loss after therapy was similar in both groups (8.0 kg in EVAC vs 9.0 kg in SEMS; p=0.356). Conclusions: EVAC can be effective endoscopic treatment for postgastrectomy anastomotic leakage. Substantial leakage could be an important clinical factor for considering EVAC as a treatment option. Large randomized controlled trials are needed to confirm the efficacy of EVAC.

Stratification of Postsurgical Computed Tomography Surveillance Based on the Extragastric Recurrence of Early Gastric Cancer.

OBJECTIVE: To stratify the postsurgical computed tomography (CT) surveillance based on a risk-scoring system for predicting extragastric recurrence after surgical resection of early gastric cancer (EGC). SUMMARY OF BACKGROUND DATA: Postsurgical CT surveillance should not be routinely performed in all patients because of the low incidence of extragastric recurrence and potential risk of radiation exposure. METHODS: Data from 3162 patients who underwent surgical resection for EGC were reviewed to develop a risk-scoring system to predict extragastric recurrence. Risk scores were based on the predictive factors for extragastric recurrence, which were determined using Cox proportional hazard regression model. The risk-scoring system was validated by Uno censoring adjusted C-index. External validation was performed using an independent dataset (n = 430). RESULTS: The overall incidence of extragastric recurrence was 1.4% (44/3162). Five risk factors (lymph node metastasis, indications for endoscopic resection, male sex, positive lymphovascular invasion, and elevated macroscopic type), which were significantly associated with extragastric recurrence, were incorporated into the risk-scoring system, and the patients were categorized into 2 risk groups. The 10-year extragastric recurrence-free survival differed significantly between low- and high-risk groups (99.7% vs 96.5%; P < 0.001). The predictive accuracy of the risk-scoring system in the development cohort was 0.870 [Uno C-index; 95% confidence interval (95% CI), 0.800-0.939]. Discrimination was good after internal (0.859) and external validation (0.782, 0.549-1.000). CONCLUSION: This risk-scoring system might be useful to predict extragastric recurrence of EGC after curative surgical resection. We suggest that postsurgical CT surveillance to detect extragastric recurrence should be avoided in the low-risk group.

Comparison of general anesthesia and conscious sedation in procedure-related complications during esophageal endoscopic submucosal dissection.

BACKGROUND: Endoscopic submucosal dissection (ESD) has a favorable outcome, compared to esophagectomy, for early esophageal neoplasia. Recent studies used general anesthesia for esophageal ESD to minimize complications due to insufficient sedation and patient movement. We aimed to evaluate the safety of general anesthesia in comparison with conscious sedation provided by anesthesiologists for esophageal ESD. METHODS: We retrospectively reviewed the electronic medical records of 158 patients who underwent esophageal ESD under general anesthesia or conscious sedation provided by anesthesiologists. We evaluated the incidence of procedure-related complications, including perforation, post-ESD bleeding, cardiopulmonary adverse events (arrhythmia, hypotension, and hypoxemia), procedure failure, stricture, and new lung consolidation after ESD. Cases of frank perforation, post-ESD bleeding requiring a vigorous diagnostic approach, and cardiopulmonary adverse events were regarded as acute complications of ESD. RESULTS: Acute complications occurred only in the conscious sedation group (8/83 [9.6%] vs. 0/75 [0.0%]; p value = 0.007). The numbers of patients with frank perforation, post-ESD bleeding, and cardiopulmonary adverse events were four, one, and three, respectively. Moreover, new lung consolidation after ESD developed only in the conscious sedation group (7/83 [8.4%] vs. 0/75 [0.0%]; p value = 0.014). ESD failed in four patients in the conscious sedation group. The incidences of stricture that required stent insertion and hospital stay after ESD were comparable between the two groups. CONCLUSION: General anesthesia is associated with a lower incidence of acute procedure-related complications in esophageal ESD compared to conscious sedation provided by anesthesiologists. Therefore, we recommend general anesthesia as a safer option for esophageal ESD.

Exploring Esophageal Microbiomes in Esophageal Diseases: A Systematic Review.

Studies that investigated esophageal microbiomes are limited when compared to those on intestinal microbiomes. Nevertheless, several studies have investigated the relationship between esophageal microbiomes and various esophageal diseases, owing to the advancement of next-generation sequencing techniques. Streptococcus is the most common bacterial taxon in a normal esophagus. Additionally, Haemophilus, Neisseria, Prevotella, and Veillonella are also found. However, gram-negative bacteria, including Prevotella, are more abundant in a diseased esophagus, such as in gastroesophageal reflux disease and Barrett's esophagus. This systematic review aims to summarize current evidences on esophageal microbiomes in various esophageal diseases.

Therapeutic potential of FLANC, a novel primate-specific long non-coding RNA in colorectal cancer.

OBJECTIVE: To investigate the function of a novel primate-specific long non-coding RNA (lncRNA), named FLANC, based on its genomic location (co-localised with a pyknon motif), and to characterise its potential as a biomarker and therapeutic target. DESIGN: FLANC expression was analysed in 349 tumours from four cohorts and correlated to clinical data. In a series of multiple in vitro and in vivo models and molecular analyses, we characterised the fundamental biological roles of this lncRNA. We further explored the therapeutic potential of targeting FLANC in a mouse model of colorectal cancer (CRC) metastases. RESULTS: FLANC, a primate-specific lncRNA feebly expressed in normal colon cells, was significantly upregulated in cancer cells compared with normal colon samples in two independent cohorts. High levels of FLANC were associated with poor survival in two additional independent CRC patient cohorts. Both in vitro and in vivo experiments demonstrated that the modulation of FLANC expression influenced cellular growth, apoptosis, migration, angiogenesis and metastases formation ability of CRC cells. In vivo pharmacological targeting of FLANC by administration of 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine nanoparticles loaded with a specific small interfering RNA, induced significant decrease in metastases, without evident tissue toxicity or pro-inflammatory effects. Mechanistically, FLANC upregulated and prolonged the half-life of phosphorylated STAT3, inducing the overexpression of VEGFA, a key regulator of angiogenesis. CONCLUSIONS: Based on our findings, we discovered, FLANC as a novel primate-specific lncRNA that is highly upregulated in CRC cells and regulates metastases formation. Targeting primate-specific transcripts such as FLANC may represent a novel and low toxic therapeutic strategy for the treatment of patients.

Statins and metachronous recurrence after endoscopic resection of early gastric cancer: a nationwide Korean cohort study.

BACKGROUND: Statins have shown to reduce the risk of various cancers. However, their effects on metachronous recurrence (MR) after endoscopic resection (ER) for early gastric cancer (EGC) are unknown. We evaluate their effects on MR development after ER for EGC. METHODS: We selected 11,568 patients who received ER for EGC from 2002 to 2011 from the Korean National Health Insurance database and classified into 2 groups: control and statins using propensity score matching. Metachronous recurrence was defined as the second ER or gastrectomy performed 6 months after the first ER. RESULTS: Mean follow-up period was 8.8 ± 3.1 years. Statins showed a significantly lower incidence of MR than the control group (12.5% vs 2.2%, respectively, P < 0.01). After conducting competing risk analyses and time-dependent cox regression analysis considering immortal time bias, statins still showed a lower incidence rate of MR compared to that observed in the control group. For the multivariate analysis, statins remained significant (HR 0.17; 95% CI 0.13-0.24, P < 0.01). In the dose-response analysis, an inverse dose-response relationship was identified between MR and statins (P < 0.01). CONCLUSION: Statins was significantly associated with a reduced risk of MR after ER for EGC with an inverse dose-response relationship.