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ABSTRACTMounting evidence indicates the potential involvement of ATP-citrate lyase (ACLY) in the modulation of various cancer types. Nevertheless, the precise biological significance of ACLY in gastric cancer (GC) remains elusive. This study sought to elucidate the biological function of ACLY and uncover its influence on peritoneal metastasis in GC. The expression of ACLY was assessed using both real-time quantitative PCR and western blot techniques. To investigate the impact of ACLY on the proliferation of gastric cancer (GC) cells, colony formation and 5-ethynyl-2’-deoxyuridine (EdU) assays were performed. The migratory and invasive abilities of GC were evaluated using wound healing and transwell assays. Additionally, a bioinformatics analysis was employed to predict the correlation between ACLY and HIF-1A. This interaction was subsequently confirmed through a chromatin immunoprecipitation (ChIP) assay. ACLY exhibited upregulation in gastric cancer (GC) as well as in peritoneal metastasis. Its overexpression was found to facilitate the proliferation and metastasis of GC cells in both in vitro and in vivo experiments. Moreover, ACLY was observed to play a role in promoting angiogenesis and epithelial-mesenchymal transition (EMT). Notably, under hypoxic conditions, HIF-1A levels were elevated, thereby acting as a transcription factor to upregulate ACLY expression. Under the regulatory influence of HIF-1A, ACLY exerts a significant impact on the progression of gastric cancer, thereby facilitating peritoneal metastasis.

Background: The aim of this retrospective matched‐paired cohort study was to clarify the effectiveness of preserving the vagus nerve in totally laparoscopic radical distal gastrectomy (TLDG). Methods: One hundred eighty-three patients with gastric cancer who underwent TLDG between February 2020 and March 2022 were included and followed up. Sixty-one patients with preservation of the vagal nerve (VPG) in the same period were matched (1:2) to conventional sacrificed (CG) cases for demographics, tumor characteristics, and tumor node metastasis stage. The evaluated variables included intraoperative and postoperative indices, symptoms, nutritional status, and gallstone formation at 1 year after gastrectomy between the two groups. Results: Although the operation time was significantly increased in the VPG compared with the CG (198.0 ± 35.2 vs. 176.2 ± 35.2 min, P< 0.001), the mean time of gas passage in the VPG was significantly lower than that in the CG (68.1 ± 21.7 h vs. 75.4 ± 22.6 h, P= 0.038). The overall postoperative complication rate was similar between the two groups (P= 0.794). There was no statistically significant difference between the two groups hospital stay, total number of harvested lymph nodes, and mean number of examined lymph nodes at each station. During follow-up, the morbidity of gallstones or cholecystitis (8.2% vs. 20.5%, P= 0.036), chronic diarrhea (3.3% vs. 14.8%, P= 0.022), and constipation (4.9% vs. 16.4%, P= 0.032) were significantly lower in the VPG than in the CG in this study. Moreover, injury to the vagus nerve was found to be an independent risk factor for gallstone formation or cholecystitis and chronic diarrhea in univariate analysis and multivariate analysis. Conclusion: The vagus nerve plays an imperative role in gastrointestinal motility, and hepatic and celiac branch preservation mainly exerts efficacy and safety in patients who undergo TLDG.

Peritoneal metastasis (PM) is an important metastatic modality of gastric cancer (GC).It is associated with poor prognosis. The underlying molecular mechanism of PM remains elusive. 5-Methylcytosine (m5C), a posttranscriptional RNA modification, involves in the progression of many tumors. However, its role in GC peritoneal metastasis remains unclear. In our study, transcriptome results suggested that NSUN2 expression was significantly upregulated in PM. And patients with high NSUN2 expression of PM predicted a worse prognosis. Mechanistically, NSUN2 regulates ORAI2 mRNA stability by m5C modification, thereby promoting ORAI2 expression and further promoting peritoneal metastasis and colonization of GC. YBX1 acts as a “reader” by binding to the ORAI2 m5C modification site. Following the uptake of fatty acids from omental adipocytes by GC cells, the transcription factor E2F1 was upregulated, which further promoted the expression of NSUN2 through cis-element. Briefly, these results revealed that peritoneal adipocytes provide fatty acid for GC cells, thus contributing to the elevation of E2F1 and NSUN2 through AMPK pathway, and upregulated NSUN2 activates the key gene ORAI2 through m5C modification, thereby promoting peritoneal metastasis and colonization of gastric cancer.

Imatinib is a tyrosine kinase inhibitor that is widely used to combat gastrointestinal stromal tumours (GISTs). However, secondary resistance to imatinib is an important challenge in GIST treatment. Recent studies have demonstrated that cancer-derived nanosized exosomes play a key role in intercellular communication, but little is known about the roles of exosomes in imatinib-resistant GISTs. Here, we reveal that exosomes released from imatinib-resistant GISTs transmit drug resistance to imatinib-sensitive tumours. By using iTRAQ technology, we demonstrate that Ras-related protein Rab-35 (Rab35) is upregulated differentially in imatinib-resistant GISTs. Loss of Rab35 decreases exosome secretion, thereby hampering the transmission of imatinib resistance to sensitive tumours. Mechanistically, we showed that the ubiquitin‒proteasome system is involved in elevated Rab35 expression and that ubiquitin-specific protease 32 (USP32), a deubiquitylating enzyme, is bound to Rab35. Further experiments demonstrate that this protease protects Rab35 from proteasomal degradation by reducing Lys48 (K48)-ubiquitination. Additionally, we found that the transcription factor ETV1, which is a lineage survival factor in GISTs, promotes USP32 expression. Collectively, our results reveal that exosomes transmit imatinib resistance in GISTs and that deubiquitylation plays a key role in regulating the transmission process. The USP32-Rab35 axis provides a potential target for interventions to reduce the occurrence of imatinib resistance in GISTs.

Secondary resistance to imatinib (IM) represents a major challenge for therapy of gastrointestinal stromal tumors (GISTs). Aberrations in oncogenic pathways, including autophagy, correlate with IM resistance. Regulation of autophagy-related protein 5 (ATG5) by the ubiquitin-proteasome system is critical for autophagic activity, although the molecular mechanisms that underpin reversible deubiquitination of ATG5 have not been deciphered fully. Here, we identified USP13 as an essential deubiquitinase that stabilizes ATG5 in a process that depends on the PAK1 serine/threonine-protein kinase and which enhances autophagy and promotes IM resistance in GIST cells. USP13 preferentially is induced in GIST cells by IM and interacts with ATG5, which leads to stabilization of ATG5 through deubiquitination. Activation of PAK1 promoted phosphorylation of ATG5 thereby enhancing the interaction of ATG5 with USP13. Furthermore, N6-methyladenosine methyltransferase-like 3 (METTL3) mediated stabilization of USP13mRNA that required the m6A reader IGF2BP2. Moreover, an inhibitor of USP13 caused ATG5 decay and co-administration of this inhibitor with 3-methyladenine boosted treatment efficacy of IM in murine xenograft models derived from GIST cells. Our findings highlight USP13 as an essential regulator of autophagy and IM resistance in GIST cells and reveal USP13 as a novel potential therapeutic target for GIST treatment.

Liver metastasis (LM) severely affects gastric cancer (GC) patients’ prognosis. Small extracellular vesicles (sEVs) play key roles in intercellular communication. Specific sEV-miRNAs from several types of cancer were found to induce a premetastatic niche in target organs before tumor cell arrive. However, whether the primary GC affects hepatic microenvironment or the role of sEV-miRNAs in GC-LM is yet unclear. We report that GC-derived sEVs are primarily absorbed by Kupffer cells (KCs). sEV-miR-151a-3p is highly expressed in GC-LM patients’ plasma and presents poor prognosis. Treating mice with sEVs-enriched in miR-151a-3p promotes GC-LM, whereas has no influence on the proliferation of GC cells in situ. Mechanistically, sEV-miR-151a-3p inhibits SP3 in KCs. Simultaneously, sEV-miR-151a-3p targets YTHDF3 to decrease the transcriptional inhibitory activity of SP3 by reducing SUMO1 translation in a N6-methyladenosine-dependent manner. These factors contribute to TGF-β1 transactivation in KCs, subsequently activating the SMAD2/3 pathway and enhancing the stem cell-like properties of incoming GC cells. Furthermore, sEV-miR-151a-3p induces miR-151a-3p transcription in KCs to form a positive feedback loop. In summary, our results reveal a previously unidentified regulatory axis initiated by sEV-miR-151a-3p that establishes a hepatic stemness-permissive niche to support GC-LM. sEV-miR-151a-3p could be a promising diagnostic biomarker and preventive treatment candidate for GC-LM.

IMPORTANCE: The safety of laparoscopic total gastrectomy (LTG) for the treatment of gastric cancer remains uncertain given the lack of high-level clinical evidence. OBJECTIVE: To compare the safety of LTG for clinical stage I gastric cancer with that of conventional open total gastrectomy (OTG). DESIGN, SETTING, AND PARTICIPANTS: The Chinese Laparoscopic Gastrointestinal Surgery Study (CLASS) Group CLASS02 study was a prospective, multicenter, open-label, noninferiority, randomized clinical trial that compared the safety of LTG vs OTG with lymphadenectomy for patients with clinical stage I gastric cancer. From January 2017 to September 2018, a total of 227 patients were enrolled. Final follow-up was in October 2018. INTERVENTIONS: Eligible patients were randomized to LTG (n = 113) or OTG (n = 114) by an interactive web response system. MAIN OUTCOMES AND MEASURES: The primary outcome was the morbidity and mortality within 30 days following surgeries between LTG and OTG with a noninferiority margin of 10%. The secondary outcomes were recovery courses and postoperative hospital stays. RESULTS: A total of 214 patients were analyzed for morbidity and mortality (105 patients in the LTG group and 109 patients in the OTG group). The mean (SD) age was 59.8 (9.4) years in the LTG group and 59.4 (9.2) years in the OTG group, and most were male (LTG group, 75 of 105 [71.4%]; OTG group, 80 of 109 [73.4%]). The overall morbidity and mortality rates were not significantly different between the groups (rate difference, −1.1%; 95% CI, −11.8% to 9.6%). Intraoperative complications occurred in 3 patients (2.9%) in the LTG group and 4 patients (3.7%) in the OTG group (rate difference, −0.8%; 95% CI, −6.5% to 4.9%). In addition, there was no significant difference in the overall postoperative complication rate of 18.1% in the LTG group and 17.4% in the OTG group (rate difference, 0.7%; 95% CI, −9.6% to 11.0%). One patient in the LTG group died from intra-abdominal bleeding secondary to splenic artery hemorrhage. However, there was no significant difference in mortality between the LTG group and the OTG group (rate difference, 1.0%; 95% CI, −2.5% to 5.2%), and the distribution of complication severity was similar between the 2 groups. CONCLUSIONS AND RELEVANCE: The results of the CLASS02 trial showed that the safety of LTG with lymphadenectomy by experienced surgeons for clinical stage I gastric cancer was comparable to that of OTG. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03007550

Purpose: The aim of this study was to compare the outcomes of laparoscopic appendectomy (LA) using purse string invaginating sutures (PS) with those using intracorporeal knotting (IK) or Hem-o-lock polymeric clips (HL). Methods: A total of 882 patients who underwent laparoscopic appendectomy from January 2015 to December 2017 were studied retrospectively. Of these, 538 patients used PS, 229 patients used IK and 115 patients used HL to close the appendiceal stump. Their demographic characteristics, intraoperative findings and postoperative complications were analysed retrospectively. Results: There were similar percentages of complicated cases in all the groups (21.7% in PS vs. 21.4% in IK vs. 24.3% in HL, p= 0.803). The mean length of hospital stay was shorter in PS group when compared to IK or HL group (3.72 + 2.35 in PS vs. 4.41 + 2.40 in IK, 4.43 + 2.66 in HL, p< 0.05) as well as lower ASA scores (1.7 + 0.6 in PS vs. 1.8 + 0.6 in IK vs. 1.7 + 0.6 in HL, p< 0.05). The overall complication rates for the PS, the HL and the IK groups were 12.1, 8.7 and 9.2%, respectively. The rate of wound infection was higher in PS group for uncomplicated appendicitis (5.0% in PS vs. 2.8% in IK and 1.1% in HL, p= 0.129). Furthermore, there were no differences in the rate of intra-abdominal infection among the groups in both uncomplicated and complicated cases. Conclusions: Based on our results, purse string suture failed to demonstrate better postoperative outcome in laparoscopic appendectomy and is no longer recommended by our institution as initial approach.

ObjectiveAlthough a subset of genetic loci have been associated with gastric cancer (GC) risk, the underlying mechanisms are largely unknown. We aimed to identify new susceptibility genes and elucidate their mechanisms in GC development.DesignWe conducted a meta-analysis of four genome-wide association studies (GWASs) encompassing 3771 cases and 5426 controls. After targeted sequencing and functional annotation, we performed in vitro and in vivo experiments to confirm the functions of genetic variants and candidate genes. Moreover, we selected 33 promising variants for two-stage replication in 7035 cases and 8323 controls from other five studies.ResultsThe meta-analysis of GWASs identified three loci at 1q22, 5p13.1 and 10q23.33 associated with GC risk at p<5×10−8 and replicated seven known loci at p<0.05. At 5p13.1, the risk rs59133000[C] allele enhanced the binding affinity of NF-κB1 (nuclear factor kappa B subunit 1) to the promoter of PRKAA1, resulting in a reduced promoter activity and lower expression. The knockout of PRKAA1promoted both GC cell proliferation and xenograft tumour growth in nude mice. At 10q23.33, the rs3781266[C] and rs3740365[T] risk alleles in complete linkage disequilibrium disrupted and created, respectively, the binding motifs of POU2F1 and PAX3, resulting in an increased enhancer activity and expression of NOC3L, while the NOC3Lknockdown suppressed GC cell growth. Moreover, two new loci at 3q11.2 (OR=1.21, p=4.56×10−9) and 4q28.1 (OR=1.14, p=3.33×10−11) were associated with GC risk.ConclusionWe identified 12 loci to be associated with GC risk in Chinese populations and deciphered the mechanisms of PRKAA1at 5p13.1 and NOC3Lat 10q23.33 in gastric tumourigenesis.

The prognosis after curative resection of gastric cancer (GC) remains unsatisfactory, and thus, the development of treatments involving alternative molecular and genetic targets is critical. Circular RNAs (circRNAs), which are newly discovered molecules with key roles in the non-coding RNA network, have been identified as critical regulators in various cancers. Here, we aimed to determine the circRNA expression profile and to investigate the functional and prognostic significance of circRNA in GC. Using next-generation sequencing profiling, we first characterized an abundant circRNA in GC, hsa_circ_0008549, derived from the OSBPL10 gene and named it circOSBPL10. The expression of circOSBPL10 was found to be upregulated in GC tissues by quantitative RT-PCR, and silencing of circOSBPL10 significantly inhibited GC cell growth, migration, and invasion in multiple experiments. We further confirmed that miR-136-5p is a downstream target of circOSBPL10 using RNA pull-down and luciferase reporter assays. Rescue experiments confirmed that circOSBPL10 regulates biological functions in GC cells via a circOSBPL10-miR-136-5p-WNT2axis. In vivo experiments showed that circOSBPL10 promotes tumor growth and metastasis in mice. Furthermore, the level of circOSBPL10 was observed to be a prognostic marker of the overall survival and disease-free survival of patients with GC. Taken together, our findings reveal that circOSBPL10 may serve as a new proliferation factor and prognostic marker in GC.

Little attention has been paid to the biocompatibility and biological effects of zinc as a material. Here, we therefore investigated the biocompatibility and anti-inflammatory and collagen-promoting effects of pure zinc material in the colorectum. Our in vitro results indicated that zinc toxicity and concentration were closely related. Low concentrations of zinc ions and pure zinc material extract had only minor effects on the viability of primary rectal mucosal epithelial cells; however, cytotoxicity was observed at concentrations greater than 0.017 μg/μL and 60%, respectively. In vivo experiments demonstrated that zinc pins degraded slowly in the colorectum (their volume decreasing by approximately 7.79% over 1 month) and did not cause serious adverse reactions. Pure zinc material was found to inhibit acute inflammation through increased expression of ENA-78 and F4/80. Moreover, zinc material heightened expression of collagen and VEGF, factors conducive to wound healing, in surrounding colorectal tissues. These preliminary results suggest that zinc shows great promise as an implant material for medical applications involving colorectal surgery.

This study aimed to clarify that the activated pancreatic stellate cells (PaSCs) are the origin of the highly expressed galectin-1 in the stroma of pancreatic ductal adenocarcinoma (PDAC) tissue and to evaluate the effect of the secreted galectin-1 on proliferation and invasion ability of pancreatic cancer cell line CFPAC-1 in vitro.

IMPORTANCE: Gastric neuroendocrine carcinoma and mixed adenoneuroendocrine carcinoma are rare pathological types of gastric cancer, and there is a lack of multicenter studies comparing the prognosis and recurrence patterns of gastric neuroendocrine carcinoma, gastric mixed adenoneuroendocrine carcinoma, and gastric adenocarcinoma. OBJECTIVE: To compare the differences in long-term survival and patterns of recurrence among gastric neuroendocrine carcinoma, gastric mixed adenoneuroendocrine carcinoma, and gastric adenocarcinoma. DESIGN, SETTING, AND PARTICIPANTS: This cohort study included patients with resectable gastric neuroendocrine carcinoma and gastric mixed adenoneuroendocrine carcinoma at 23 hospitals in China from January 2006 to December 2016. In addition, patients with gastric adenocarcinoma were selected as controls. Propensity score–matched analysis was used to match pathological stage among the different pathological types, and disease-free survival (DFS), postrecurrence survival (PRS), and patterns of recurrence were examined. Data analysis was conducted from July 15, 2020, to October 21, 2020. EXPOSURES: Curative resection for gastric neuroendocrine carcinoma, gastric mixed adenoneuroendocrine carcinoma, and gastric adenocarcinoma. MAIN OUTCOMES AND MEASURES: The main outcomes were DFS and patterns of recurrence. RESULTS: A total of 3689 patients were analyzed (median [interquartile range] age, 62 [55-69] years; 2748 [74.5%] men), including 503 patients (13.6%) with gastric neuroendocrine carcinoma, 401 patients (10.9%) with gastric mixed adenoneuroendocrine carcinoma, and 2785 patients (75.5%) with gastric adenocarcinoma. After propensity score matching, 5-year DFS was 47.6% (95% CI, 42.7%-52.5%) for patients with gastric neuroendocrine carcinoma, compared with 57.6% (95% CI, 55.1%-60.1%) with gastric adenocarcinoma (P?&lt;?.001) and 51.1% (95% CI, 46.0%-56.2%) for patients with gastric mixed adenoneuroendocrine carcinoma, compared with 57.8% (95% CI, 55.1%-60.5%) patients with gastric adenocarcinoma (P?=?.02). Multivariable analyses found that, compared with gastric adenocarcinoma, gastric neuroendocrine carcinoma (hazard ratio [HR], 1.64; 95% CI, 1.40-1.93) and gastric mixed adenoneuroendocrine carcinoma (HR, 1.25; 95% CI, 1.05-1.49) were independent risk factors associated with worse DFS. Compared with matched patients with gastric adenocarcinoma, patients with gastric neuroendocrine carcinoma were more likely to have distant recurrence (268 patients [17.2%] vs 101 patients [23.7%]; P?=?.002), as were patients with gastric mixed adenoneuroendocrine carcinoma (232 patients [17.3%] vs 76 patients [22.8%]; P?=?.02). In multivariate analysis, gastric neuroendocrine carcinoma (HR, 2.22; 95% CI, 1.66-2.98) and gastric mixed adenoneuroendocrine carcinoma (HR, 1.70; 95% CI, 1.24-2.34) were independent risk factors associated with distant recurrence. Additionally, T3 to T4 stage (odds ratio, 2.84; 95% CI, 1.57-5.14; P?=?.001) and lymph node metastasis (odds ratio, 2.01; 95% CI, 1.31-3.10; P?=?.002) were independent risk factors associated with distant recurrence of gastric neuroendocrine carcinoma and gastric mixed adenoneuroendocrine carcinoma. CONCLUSIONS AND RELEVANCE: This cohort study found that patients with gastric neuroendocrine carcinoma or gastric mixed adenoneuroendocrine carcinoma had worse prognoses and were more prone to distant recurrence than those with gastric adenocarcinoma. Thus, different follow-up and treatment strategies should be developed to improve the long-term survival of patients with gastric neuroendocrine carcinoma or gastric mixed adenoneuroendocrine carcinoma, especially patients with tumors penetrating into the subserosa or deeper layers or with lymph node metastasis.