Individualized Endoscopic Surveillance for Metachronous Gastric Cancer After Endoscopic Submucosal Dissection: A Retrospective Observational Study.

BACKGROUND/AIMS: Endoscopic submucosal dissection has been widely applied for curative resection of early gastric cancer or high-grade dysplasia, and metachronous gastric cancer is a major issue after endoscopic therapy. Here, we studied the recurrence patterns of metachronous gastric cancer and its correlation with the primary lesions. MATERIALS AND METHODS: A total of 286 consecutive patients undergoing endoscopic submucosal dissection for early gastric cancer or high-grade dysplasia between March 2011 and March 2018 were retrospectively reviewed. Metachronous gastric cancer was defined as a new gastric cancer detected more than 1 year after endoscopic submucosal dissection. RESULTS: During a median follow-up of 36 months, 24 patients developed metachronous gastric cancer. The 5-year cumulative incidence was 13.4% and the annual incidence was 24.3 cases per 1000 person-years. Subgroup analysis revealed that the third year after early gastric cancer resection and the fifth year after high-grade dysplasia resection were the predilection periods of metachronous gastric cancer. Correlation analysis suggested that the metachronous and primary lesions showed a significant correlation in cross-sectional position (C = 0.627, P = .027) but not in pathological characteristics (P > .05). When the primary lesions were located in the posterior walls, the metachronous lesions were prone to occur in the lesser curvatures (C = 0.494, P = .008) and the reverse was also true (C = 0.422, P = .029). CONCLUSIONS: The predilection periods and common sites of metachronous gastric cancer are associated with the primary lesions. Meticulous individualized endoscopic surveillance after endoscopic submucosal dissection requires to be conducted, taking into account the characteristics of primary lesions.

Deoxycholic acid induces gastric intestinal metaplasia by activating STAT3 signaling and disturbing gastric bile acids metabolism and microbiota.

Intestinal metaplasia (IM) is the inevitable precancerous stage to develop intestinal-type gastric cancer (GC). Deoxycholic acid (DCA) is the main bile acid (BA) component of duodenogastric reflux and has shown an increased concentration during the transition from chronic gastritis to IM associated with continued STAT3 activation. However, the mechanisms underlying how DCA facilitates IM in the gastric epithelium need exploration. We evaluated IM and bile reflux in corpus tissues from 161 subjects undergoing GC screening. Cell survival and proliferation, proinflammatory cytokine expression and TGR5/STAT3/KLF5 axis activity were measured in normal human gastric cells, cancer cells, and organoid lines derived from C57BL/6, FVB/N and insulin-gastrin (INS-GAS) mice treated with DCA. The effects of DCA on IM development were determined in INS-GAS mice with long-term DCA supplementation, after which the gastric bacterial and BA metabolic profiles were measured by 16S rRNA gene sequencing and LC-MS. We revealed a BA-triggered TGR5/STAT3/KLF5 pathway in human gastric IM tissues. In gastric epithelial cells, DCA promoted proliferation and apoptotic resistance, upregulated proinflammatory cytokines and IM markers, and facilitated STAT3 phosphorylation, nuclear accumulation and DNA binding to the KLF5 promoter. DCA triggered STAT3 signaling and the downstream IM marker KLF5 in mouse gastric organoids in vitro and in vivo. In INS-GAS mice, DCA promoted the accumulation of serum total BAs and accelerated the stepwise development of gastric IM and dysplasia. DCA induced gastric environmental alterations involving abnormal BA metabolism and microbial dysbiosis, in which the Gemmobacter and Lactobacillus genera were specifically enriched. Lactobacillus genus enrichment was positively correlated with increased levels of GCA, CA, T-α-MCA, TCA and ß-MCA in DCA-administrated INS-GAS mice. DCA promotes nuclear STAT3 phosphorylation, which mediates KLF5 upregulation associated with gastric inflammation and IM development. DCA disturbs the gastric microbiome and BA metabolism homeostasis during IM induction.

The efficacy and long-term outcomes of endoscopic full-thickness suturing for chronic gastrointestinal fistulas with an Overstitch device: is it a durable closure?

BACKGROUND AND AIM: Endoscopic closure of chronic gastrointestinal fistulas (CGFs) is challenging due to their epithelialized surfaces. The aim of this study was to assess the efficacy and long-term closure rate of endosuturing for CGFs with an Apollo Overstitch device. PATIENTS AND METHODS: Consecutive CGF patients undergoing endosuturing for fistula closure from April 2018 to January 2020 at the First Affiliated Hospital of Nanjing Medical University were enrolled for retrospective review. Demographics, fistula characteristics, details of the suturing procedures and outcomes were collected for analysis. RESULTS: Twenty patients (mean age 59.8 ± 9.1 years; 85% males) with a total of 23 CGFs underwent sutured fistula closure. Esophagotracheal fistulas were the most common CGFs (12/23, 52.2%), and prior cancer surgery was the most common fistulization etiology (14/20, 70%). Twelve patients (12/20, 60%) had undergone failed endoscopic attempts at fistula closure before suturing. Additional endoscopic therapies used during suturing were 100% argon plasma coagulation, 50% clip fixation, and 10% stent placement. Although all patients undergoing suturing achieved immediate technical success of fistula closure, sustained fistula closure was observed in only 5 patients (5/20, 25.0%) on surveillance endoscopy 3 months after suturing with a mean follow-up of 19.5 months. Esophagotracheal fistula patients were predisposed to shorter dehiscence-free survival than those with other fistulas (HR 3.378; 95% CI 1.127-10.13). CONCLUSIONS: Endosuturing is safe and should be considered for use as the first-line or salvage therapy for CGF closure, primarily for patients with fistulas not involving the trachea. However, the long-term healing of CGFs by suturing is challenging, and CGF patients might not benefit from repeated suturing.

Circular RNA circDNA2 upregulates CCDC6 expression to promote the progression of gastric cancer via miR-149-5p suppression.

Circular (circ)RNAs are widely involved in gastric cancer (GC) pathogenesis, and coiled-coil domain containing 6 (CCDC6) is a fused partner of multiple oncogenes; however, the underlying mechanisms of how circRNAs regulate CCDC6 expression in the progression and prognosis of GC remain unclear. Here, we discovered the circRNA derived from the DNA2 gene locus (circDNA2) through RNA sequencing. By performing quantitative real-time PCR and fluorescence in situ hybridization (FISH) assays with a human tissue microarray, circDNA2 was found to be highly expressed in GC tissues and associated with lymphatic invasion of GC patients. Knockdown of circDNA2 expression suppressed the proliferation of GC cells by reducing CCDC6 expression. Mechanistically, circDNA2 acted as a microRNA (miR)-149-5p sponge, which was confirmed to target CCDC6 by RNA pulldown and dual-luciferase reporter assays and rescue experiments. Both low miR-149-5p expression and high CCDC6 expression were related to unfavorable prognosis in GC patients. Moreover, GC patients with low miR-149-5p expression had shorter overall survival and a higher risk of chemotherapy resistance than those with high miR-149-5p expression. In summary, circDNA2 contributes to the growth and lymphatic metastasis of GC by upregulating CCDC6 expression by sponging miR-149-5p. The circDNA2/miR-149-5p/CCDC6 axis might be developed as a therapeutic target and prognostic indicator for GC.

Evaluation of the Diagnostic Potential of a Plasma Exosomal miRNAs Panel for Gastric Cancer.

PURPOSE: Gastric cancer (GC) is often difficult to diagnose early in the disease and remains one of the most frequently occurring malignancies. This investigation looks at the diagnostic potential of a specific plasma exosomal miRNAs panel for GC. METHODS: This study analyzed 216 individual peripheral blood samples. 2 GEO datasets were analyzed and two miRNAs were selected - plasma exosomal miR-195-5p and miR-211-5p. Quantitative reverse-transcriptase PCR (qRT-PCR) was used to assess relative expressions and receiver operating characteristic (ROC) curve analysis was used to determine the diagnostic efficiency of miR-195-5p and miR-211-5p panel. The Kaplan-Meier method was used to assess the prognostic value of plasma exosomal miR-195-5p and miR-211-5p. RESULTS: GC patients possessed notably raised plasma levels of exosomal miR-195-5p and miR-211-5p. The area under ROC curves (AUCs) of miR-195-5p, miR-211-5p were 0.745, 0.798 in the screening phase and 0.762, 0.798 in the training stage respectively. GC was able to be diagnosed more accurately when both miRNAs were interpreted together (AUC=0.820 in the validation stage). Poorer prognosis was observed in GC patients who had plasma exosomal miR-195-5p and miR-211-5p of higher levels. In vitro experiments also confirmed that miR-195-5p and miR-211-5p is able to be transmitted between cells, and works to enhance tumor invasion, migration and proliferation while inhibiting cell apoptosis. CONCLUSION: Plasma exosomal miR-195-5p and miR-211-5p may become potential biomarkers for GC diagnosis, and may be useful in predicting tumor phenotype.

Antibiotic susceptibility guided reuse of levofloxacin-based therapy in a penicillin-allergic patient for Helicobacter pylori infection: A case report.

RATIONALE: Antibiotic resistance poses a challenge for Helicobacter pylori eradication treatment. Current guidelines strongly recommend avoiding repeated treatments with the same antibiotic to prevent the emergence of drug resistance. However, for penicillin-allergic patients with recurrent H. pylori eradication failures, avoiding repeated treatments with the same antibiotic severely limits the choice of treatment. PATIENT CONCERNS: A 47-year-old woman with a penicillin allergy for whom 2 previous levofloxacin and bismuth-based therapies had failed. DIAGNOSIS: H. pylori infection. INTERVENTIONS: Agar dilution susceptibility testing and gene sequence analysis was performed to confirm levofloxacin susceptibility again. Therefore, we treated her with a 14-day regimen consisting of levofloxacin (500 mg once daily), furazolidone (100 mg twice daily), colloidal bismuth pectin (220 mg twice daily), and esomeprazole (20 mg twice daily). OUTCOMES: The patient was successfully treated with a third levofloxacin and bismuth-based regimen. LESSONS: Antibiotics included in previous failed therapies need not be eliminated if no antibiotic resistance is found on antimicrobial susceptibility testing.

circCUL2 regulates gastric cancer malignant transformation and cisplatin resistance by modulating autophagy activation via miR-142-3p/ROCK2.

BACKGROUND: Circular RNAs (circRNAs) are a class of noncoding RNAs (ncRNAs) and can modulate gene expression by binding to miRNAs; further, circRNAs have been shown to participate in several pathological processes. However, the expression and biological function of circCUL2 in gastric cancer (GC) remains largely unknown. METHODS: circRNA microarrays and quantitative real-time PCR (qRT-PCR) were used to identify differentially expressed circRNAs in GC tissues and cell lines. circCUL2 knockdown and overexpression were performed to indicate the functional role of circCUL2 in vitro and in vivo. The expression and regulation of circCUL2, miR-142-3p and ROCK2 were evaluated using fluorescence in situ hybridization (FISH), dual-luciferase assays, RNA pull-down assays, RNA immunoprecipitation (RIP) and rescue experiments. Furthermore, the regulation of cisplatin sensitivity and autophagy by circCUL2/miR-142-3p/ROCK2 was demonstrated by cellular apoptosis assays, western blot, immunofluorescence and transmission electron microscopy analyses. RESULTS: The level of circCUL2, which is stable and cytoplasmically localized, was significantly reduced in GC tissues and cells. Overexpressed circCUL2 inhibited malignant transformation in vitro and tumorigenicity in vivo. In the AGS and SGC-7901 cell lines, circCUL2 sponged miR-142-3p to regulate ROCK2, thus modulating tumor progression. Furthermore, in the AGS/DDP and SGC-7901/DDP cell lines, circCUL2 regulated cisplatin sensitivity through miR-142-3p/ROCK2-mediated autophagy activation. CONCLUSION: circCUL2 may function as a tumor suppressor and regulator of cisplatin sensitivity through miR-142-3p/ROCK2-mediated autophagy activation, which could be a key mechanism and therapeutic target for GC.

Exosomal transfer of miR-15b-3p enhances tumorigenesis and malignant transformation through the DYNLT1/Caspase-3/Caspase-9 signaling pathway in gastric cancer.

BACKGROUND: Exosomes are essential for tumor growth, metastasis, and are used as novel signaling molecules in targeted therapies. Therefore, exosomal miRNAs can be used in new diagnostic and therapeutic approaches due to their involvement in the development of cancers. However, the detailed biological function, potential molecular mechanism and clinical application of exo-miR-15b-3p in gastric cancer (GC) remains unclear. METHODS: miR-15b-3p mRNA levels in tissues, serum, cells and exosomes were analyzed using qRT-PCR assays. qRT-PCR, immunohistochemical and western blotting analyses were utilized for the determination of DYNLT1 expression. The interrelationship connecting miR-15b-3p with DYNLT1 was verified using Dual-luciferase report, western blotting and qRT-PCR assays. Fluorescent PKH-26 or GFP-Lv-CD63 labeled exosomes, as well as Cy3-miR-15b-3p, were utilized to determine the efficacy of the transfer of exo-miR-15b-3p between BGC-823 and recipient cells. Several in vitro assays and xenograft tumor models were conducted to determine exo-miR-15b-3p impact on GC progression. RESULTS: This is the first study to confirm high miR-15b-3p expression in GC cell lines, tissues and serum. Exosomes obtained from 108 GC patient serum samples and GC cell-conditioned medium were found to show upregulation of exo-miR-15b-3p, with the area under the ROC curve (AUC) being 0.820 [0.763-0.876], which is superior to the AUC of tissues and serum miR-15b-3p (0.674 [0.600-0.748] and 0.642 [0.499-0.786], respectively). In addition, high exo-miR-15b-3p expression in serum was found to accurately predict worse overall survival. SGC-7901 and GES-1 cells are capable of internalizing BGC-823 cell-derived exosomes, allowing the transfer of miR-15b-3p. Migration, invasion, proliferation and inhibition of apoptosis in vitro and in vivo were enhanced by exo-miR-15b-3p, by restraining DYNLT1, Cleaved Caspase-9 and Caspase-3 expression. CONCLUSIONS: This study identified a previously unknown regulatory pathway, exo-miR-15b-3p/DYNLT1/Caspase-3/Caspase-9, which promotes GC development and GES-1 cell malignant transformation. Therefore, serum exo-miR-15b-3p may be a potential GC diagnosis and prognosis biomarker, which can be used in precise targeted GC therapy.

The safety and efficacy of 2% vitamin C solution spray for relief of mucosal irritation caused by Lugol chromoendoscopy: a multicenter, randomized, double-blind, parallel trial.

BACKGROUND AND AIMS: Lugol chromoendoscopy facilitates endoscopic visualization of esophageal dysplasia and carcinoma. Vitamin C solution (VCS) can theoretically neutralize free iodine, which causes mucosal irritation. The aim was to assess the safety and efficacy of VCS for relieving adverse symptoms caused by Lugol iodine staining. METHODS: Two hundred forty eligible patients were randomized to receive 20 mL of normal saline solution (NS), 5% sodium thiosulfate solution (STS), or 2% VCS after spraying 10 mL of 2% Lugol iodine solution on the mid-distal esophagus. The primary endpoints were statistically significant reductions in acute and late adverse symptom severity scores. The secondary endpoint was the discoloration effect on esophageal brown iodine-stained mucosa. RESULTS: Spraying both VCS and STS similarly decreased the severity scores of acute (NS vs VCS = 2.58 vs 1.61, P = .040; VCS vs STS = 1.61 vs 1.89, P > .999) and late (NS vs VCS = 1.70 vs 0.91, P = .002; VCS vs STS = 0.91 vs 1.38; P = .212) adverse symptoms after Lugol chromoendoscopy compared with spraying NS. Compared with STS spray, VCS spray alleviated acute acid regurgitation or heartburn (33% vs 15%, P = .017) and late retrosternal discomfort or pain (21% vs 9%, P = .027). Moreover, compared with spraying NS, spraying VCS quickly discolored the iodine-stained mucosa, with a better decolorization score (2.26 vs 3.56, P = .000), and the effects of fading iodine dye were similar between VCS and STS (3.56 vs 3.59, P = .908). CONCLUSIONS: VCS can reduce mucosal irritation symptoms induced by Lugol chromoendoscopy and can be routinely recommended. (Chinese Clinical Trial Registry number: ChiCTR1900022000.).

Clostridium butyricum, a butyrate-producing probiotic, inhibits intestinal tumor development through modulating Wnt signaling and gut microbiota.

Gut microbiota dysbiosis is closely involved in intestinal carcinogenesis. A marked reduction in butyrate-producing bacteria has been observed in patients with colorectal cancer (CRC); nevertheless, the potential benefit of butyrate-producing bacteria against intestinal tumor development has not been fully investigated. We found that Clostridium butyricum (C. butyricum, one of the commonly used butyrate-producing bacteria in clinical settings) significantly inhibited high-fat diet (HFD)-induced intestinal tumor development in Apcmin/+ mice. Moreover, intestinal tumor cells treated with C. butyricum exhibited decreased proliferation and increased apoptosis. Additionally, C. butyricum suppressed the Wnt/ß-catenin signaling pathway and modulated the gut microbiota composition, as demonstrated by decreases in some pathogenic bacteria and bile acid (BA)-biotransforming bacteria and increases in some beneficial bacteria, including short-chain fatty acid (SCFA)-producing bacteria. Accordingly, C. butyricum decreased the fecal secondary BA contents, increased the cecal SCFA quantities, and activated G-protein coupled receptors (GPRs), such as GPR43 and GPR109A. The anti-proliferative effect of C. butyricum was blunted by GPR43 gene silencing using small interfering RNA (siRNA). The analysis of clinical specimens revealed that the expression of GPR43 and GPR109A gradually decreased from human normal colonic tissue to adenoma to carcinoma. Together, our results show that C. butyricum can inhibit intestinal tumor development by modulating Wnt signaling and gut microbiota and thus suggest the potential efficacy of butyrate-producing bacteria against CRC.

Low detection rate of advanced neoplasia within 5 years after polypectomy of small serrated adenoma.

AIM: Patients with small serrated adenomas (SAs) (<10 mm) often undergo surveillance colonoscopy before the routine recommended time. We aimed to determine the appropriate surveillance intervals following polypectomy of small SAs for symptomatic patients. METHOD: We retrospectively reviewed the data of 638 patients, including 122 cases and 516 controls. Subjects in the case group had small SAs at baseline colonoscopy, including sessile SA/polyps and traditional SAs, while subjects in the control group had negative findings. All patients underwent at least one surveillance colonoscopy during the following 5 years. RESULTS: There was no significant difference in the incidence rate of advanced neoplasia between the two groups over a 5-year duration (3.6% vs 2.6%, p=0.455). Moreover, both groups also showed a low prevalence of SA formation over 1-5 years (3.6% vs 1.0%, p=0.145). Patients with baseline SA tended to undergo the first surveillance colonoscopy earlier than those without adenoma (≤1 year vs 1 to ≤3 years). Seventy-one (11.1%) of the total included subjects underwent inadequate initial colonoscopy, and 30 (42.3%) underwent early surveillance of adenoma formation within 1 year. Patients with a family history of colorectal cancer (OR 4.69, 95% CI 1.48 to 14.71, p=0.017) or inadequate baseline colonoscopy (OR 3.17, 95% CI 1.202 to 8.409, p=0.035) were at a higher risk of metachronous adenoma formation during the surveillance period. CONCLUSION: Patients with small SAs at baseline gain little benefit from follow-up of colonoscopy within 5 years after complete polypectomy.

Fecal microbiota transplantation in cancer management: Current status and perspectives.

The human gut is home to a large and diverse microbial community, comprising about 1,000 bacterial species. The gut microbiota exists in a symbiotic relationship with its host, playing a decisive role in the host's nutrition, immunity and metabolism. Accumulating studies have revealed the associations between gut dysbiosis or some special bacteria and various cancers. Emerging data suggest that gut microbiota can modulate the effectiveness of cancer therapies, especially immunotherapy. Manipulating the microbial populations with therapeutic intent has become a hot topic of cancer research, and the most dramatic manipulation of gut microbiota refers to fecal microbiota transplantation (FMT) from healthy individuals to patients. FMT has demonstrated remarkable clinical efficacy against Clostridium difficile infection (CDI) and it is highly recommended for the treatment of recurrent or refractory CDI. Lately, interest is growing in the therapeutic potential of FMT for other diseases, including cancers. We briefly reviewed the current researches about gut microbiota and its link to cancer, and then summarized the recent preclinical and clinical evidence to indicate the potential of FMT in cancer management as well as cancer-treatment associated complications. We also presented the rationale of FMT for cancer management such as reconstruction of intestinal microbiota, amelioration of bile acid metabolism, and modulation of immunotherapy efficacy. This article would help to better understand this new therapeutic approach for cancer patients by targeting gut microbiota.

Dietary feeding of freeze-dried whole cranberry inhibits intestinal tumor development in Apcmin/+ mice.

It is increasingly perceived that dietary components have been linked with the prevention of intestinal cancer. Cranberry is a rich source of phenolic constituents and non-digestible fermentable dietary fiber, which shows anti-proliferation effect in colorectal cancer cells. Herein, we investigated the efficacy of long-term cranberry diet on intestinal adenoma formation in Apcmin/+ mice. Apcmin/+ mice were fed a basal diet or a diet containing 20% (w/w) freeze-dried whole cranberry powder for 12 weeks, and the number and size of tumors were recorded after sacrifice. Our results showed that cranberry strongly prevented the growth of intestinal tumors by 33.1%. Decreased cell proliferation and increased apoptosis were observed in tumors of cranberry-fed mice. Cranberry diet reduced the expression profile of colonic inflammatory cytokines (IFN-γ, IL-1ß and TNF-α) accompanied with increased levels of anti-inflammatory cytokines (IL-4 and IL-10). Moreover, the number of colonic goblet cells and MUC2 production were increased, and the intestinal barrier function was also improved. In addition, cranberry diet increased caecal short chain fatty acids concentrations, and down-regulated epidermal growth factor receptor signaling pathway. These data firstly show the efficacy and associated mechanisms of cranberry diet on intestinal tumor growth in Apcmin/+ mice, suggesting its chemopreventive potential against intestinal cancer.

Regulation of the serotonin transporter in the pathogenesis of irritable bowel syndrome.

Serotonin (5-HT) and the serotonin transporter (SERT) have earned a tremendous amount of attention regarding the pathogenesis of irritable bowel syndrome (IBS). Considering that enteric 5-HT is responsible for the secretion, motility and perception of the bowel, the involvement of altered enteric 5-HT metabolism in the pathogenesis of IBS has been elucidated. Higher 5-HT availability is commonly associated with depressed SERT mRNA in patients with IBS compared with healthy controls. The expression difference of SERT between IBS patients and healthy controls might suggest that SERT plays an essential role in IBS pathogenesis, and SERT was expected to be a novel therapeutic target for IBS. Progress in this area has begun to illuminate the complex regulatory mechanisms of SERT in the etiology of IBS. In this article, current insights regarding the regulation of SERT in IBS are provided, including aspects of SERT gene polymorphisms, microRNAs, immunity and inflammation, gut microbiota, growth factors, among others. Potential SERT-directed therapies for IBS are also described. The potential regulators of SERT are of clinical importance and are important for better understanding IBS pathophysiology and therapeutic strategies.

[Rosiglitazone improves learning and memory impairment of 3 x Tg mice].

This study is to investigate the protective effect of rosiglitazone (RSG) against learning and memory impairment of APP/PS1/tau transgenic mice. AD mice model was replicated by using 6-month APP/PS1/tau transgenic mice. The learning and memory ability of mice was evaluated by Morris water maze and Western blotting assays was applied to measure the phosphorylation and O-glycosylation of Tau and neurofilaments (NFs) protein. The results demonstrated that RSG could reverse the learning and memory deficits of 3 x Tg mice significantly. It was also found that RSG could suppress the hyperphosphorylation of Tau and NFs protein levels and increase the glycosylation expression of Tau and NFs proteins in 3 x Tg mice brain. Together, RSG ameliorates cognitive impairments of 3 x Tg mice via the alleviation of the hyperphosphorylated Tau and NFs proteins burden in the brain.