Uncut Roux-en-Y reconstruction after distal gastrectomy for gastric cancer.

BACKGROUND: Choosing an optimal reconstruction method is pivotal for patients with gastric cancer undergoing distal gastrectomy. The uncut Roux-en-Y reconstruction, a variant of the conventional Roux-en-Y approach (or variant of the Billroth II reconstruction), employs uncut devices to occlude the afferent loop of the jejunum. This modification is designed to mitigate postgastrectomy syndrome and enhance long-term functional outcomes. However, the comparative benefits and potential harms of this approach compared to other reconstruction techniques remain a topic of debate. OBJECTIVES: To assess the benefits and harms of uncut Roux-en-Y reconstruction after distal gastrectomy in patients with gastric cancer. SEARCH METHODS: We searched CENTRAL, PubMed, Embase, WanFang Data, China National Knowledge Infrastructure, and clinical trial registries for published and unpublished trials up to November 2023. We also manually reviewed references from relevant systematic reviews identified by our search. We did not impose any language restrictions. SELECTION CRITERIA: We included randomised controlled trials (RCTs) and quasi-RCTs comparing uncut Roux-en-Y reconstruction versus other reconstructions after distal gastrectomy for gastric cancer. The comparison groups encompassed other reconstructions such as Billroth I, Billroth II (with or without Braun anastomosis), and Roux-en-Y reconstruction. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodological procedures. The critical outcomes included health-related quality of life at least six months after surgery, major postoperative complications within 30 days after surgery according to the Clavien-Dindo Classification (grades III to V), anastomotic leakage within 30 days, changes in body weight (kg) at least six months after surgery, and incidence of bile reflux, remnant gastritis, and oesophagitis at least six months after surgery. We used the GRADE approach to evaluate the certainty of the evidence. MAIN RESULTS: We identified eight trials, including 1167 participants, which contributed data to our meta-analyses. These trials were exclusively conducted in East Asian countries, predominantly in China. The studies varied in the types of uncut devices used, ranging from 2- to 6-row linear staplers to suture lines. The follow-up periods for long-term outcomes spanned from 3 months to 42 months, with most studies focusing on a 6- to 12-month range. We rated the certainty of evidence from low to very low. Uncut Roux-en-Y reconstruction versus Billroth II reconstruction In the realm of surgical complications, very low-certainty evidence suggests that uncut Roux-en-Y reconstruction compared with Billroth II reconstruction may make little to no difference to major postoperative complications (risk ratio (RR) 0.98, 95% confidence interval (CI) 0.24 to 4.05; I² = 0%; risk difference (RD) 0.00, 95% CI -0.04 to 0.04; I² = 0%; 2 studies, 282 participants; very low-certainty evidence) and incidence of anastomotic leakage (RR 0.64, 95% CI 0.29 to 1.44; I² not applicable; RD -0.00, 95% CI -0.03 to 0.02; I² = 32%; 3 studies, 615 participants; very low-certainty evidence). We are very uncertain about these results. Focusing on long-term outcomes, low- to very low-certainty evidence suggests that uncut Roux-en-Y reconstruction compared with Billroth II reconstruction may make little to no difference to changes in body weight (mean difference (MD) 0.04 kg, 95% CI -0.84 to 0.92 kg; I² = 0%; 2 studies, 233 participants; low-certainty evidence), may reduce the incidence of bile reflux into the remnant stomach (RR 0.67, 95% CI 0.55 to 0.83; RD -0.29, 95% CI -0.43 to -0.16; number needed to treat for an additional beneficial outcome (NNTB) 4, 95% CI 3 to 7; 1 study, 141 participants; low-certainty evidence), and may have little or no effect on the incidence of remnant gastritis (RR 0.27, 95% CI 0.01 to 5.06; I2 = 78%; RD -0.15, 95% CI -0.23 to -0.07; I2 = 0%; NNTB 7, 95% CI 5 to 15; 2 studies, 265 participants; very low-certainty evidence). No studies reported on quality of life or the incidence of oesophagitis. Uncut Roux-en-Y reconstruction versus Roux-en-Y reconstruction In the realm of surgical complications, very low-certainty evidence suggests that uncut Roux-en-Y reconstruction compared with Roux-en-Y reconstruction may make little to no difference to major postoperative complications (RR 4.74, 95% CI 0.23 to 97.08; I² not applicable; RD 0.01, 95% CI -0.02 to 0.04; I² = 0%; 2 studies, 256 participants; very low-certainty evidence) and incidence of anastomotic leakage (RR 0.34, 95% CI 0.05 to 2.08; I² = 0%; RD -0.02, 95% CI -0.06 to 0.02; I² = 0%; 2 studies, 213 participants; very low-certainty evidence). We are very uncertain about these results. Focusing on long-term outcomes, very low-certainty evidence suggests that uncut Roux-en-Y reconstruction compared with Roux-en-Y reconstruction may increase the incidence of bile reflux into the remnant stomach (RR 10.74, 95% CI 3.52 to 32.76; RD 0.57, 95% CI 0.43 to 0.71; NNT for an additional harmful outcome (NNTH) 2, 95% CI 2 to 3; 1 study, 108 participants; very low-certainty evidence) and may make little to no difference to the incidence of remnant gastritis (RR 1.18, 95% CI 0.69 to 2.01; I² = 60%; RD 0.03, 95% CI -0.03 to 0.08; I² = 0%; 3 studies, 361 participants; very low-certainty evidence) and incidence of oesophagitis (RR 0.82, 95% CI 0.53 to 1.26; I² = 0%; RD -0.02, 95% CI -0.07 to 0.03; I² = 0%; 3 studies, 361 participants; very low-certainty evidence). We are very uncertain about these results. Data were insufficient to assess the impact on quality of life and changes in body weight. AUTHORS' CONCLUSIONS: Given the predominance of low- to very low-certainty evidence, this Cochrane review faces challenges in providing definitive clinical guidance. We found the majority of critical outcomes may be comparable between the uncut Roux-en-Y reconstruction and other methods, but we are very uncertain about most of these results. Nevertheless, it indicates that uncut Roux-en-Y reconstruction may reduce the incidence of bile reflux compared to Billroth-II reconstruction, albeit with low certainty. In contrast, compared to Roux-en-Y reconstruction, uncut Roux-en-Y may increase bile reflux incidence, based on very low-certainty evidence. To strengthen the evidence base, further rigorous and long-term trials are needed. Additionally, these studies should explore variations in surgical procedures, particularly regarding uncut devices and methods to prevent recanalisation. Future research may potentially alter the conclusions of this review.

The KDM6A-SPARCL1 axis blocks metastasis and regulates the tumour microenvironment of gastrointestinal stromal tumours by inhibiting the nuclear translocation of p65.

BACKGROUND: It is urgent to explore the pathogenic mechanism of gastrointestinal stromal tumours (GISTs). KDM6A, a histone demethylase, can activate gene transcription and has not been reported in GISTs. SPARCL1 may serve as a metastasis marker in GIST, but the molecular mechanism remains to be further explored. This study aimed to explore the biological function and molecular mechanism of KDM6A and SPARCL1 in GIST. METHODS: CCK-8, live cell count, colony formation, wound-healing and Transwell migration and invasion assays were employed to detect the cell proliferation, migration and invasion. A xenograft model and hepatic metastasis model were used to assess the role of KDM6A and SPARCL1 in vivo. RESULTS: KDM6A inhibited the proliferation, migration and invasion of GIST cells. Mechanistically, KDM6A promotes the transcription of SPARCL1 by demethylating histone H3 lysine trimethylation and consequently leads to the inactivation of p65. SPARCL1 affected the metastasis of GIST cells in a mesenchymal-epithelial transition- and matrix-metalloproteinase-dependent manner. SPARCL1 knockdown promoted angiogenesis, M2 polarisation and macrophage recruitment by inhibiting the phosphorylation of p65. Moreover, KDM6A and SPARCL1 inhibited hepatic metastasis and macrophage infiltration in vivo. CONCLUSIONS: Our findings establish the critical role of the KDM6A-SPARCL1-p65 axis in restraining the malignancy of GIST.

Neoadjuvant and/or adjuvant chemotherapy for gastric cancer patients with microsatellite instability or deficient mismatch repair: a systematic review and meta-analysis study protocol.

INTRODUCTION: Whether gastric cancer (GC) patients with deficient mismatch repair or microsatellite instability-high (dMMR/MSI-H) benefit from perioperative (neoadjuvant and/or adjuvant) chemotherapy is controversial. This protocol delineates the planned scope and methods for a systematic review and meta-analysis that aims to compare the efficacy of perioperative chemotherapy with surgery alone in resectable dMMR/MSI-H GC patients. METHODS AND ANALYSIS: This study protocol is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols-P guideline. PubMed, Embase, Cochrane (CENTRAL), and the Web of Science databases will be searched, supplemented by a secondary screening of relevant records. Both randomised controlled trials and non-randomised studies will be included in this study. The primary and secondary outcomes under scrutiny will be overall survival, disease-free survival and progression-free survival. Two reviewers will independently screen studies, extract data and assess the risk of bias. We will analyse different treatment settings (eg, neoadjuvant or adjuvant or combined as perioperative chemotherapies) separately and conduct sensitivity analyses. ETHICS AND DISSEMINATION: No ethics approval is required for this systematic review and meta-analysis, as no individual patient data will be collected. The findings of our study will be published in a peer-reviewed journal. PROSPERO REGISTRATION NUMBER: CRD42023494276.

Computed tomography radiogenomics: A potential tool for prediction of molecular subtypes in gastric stromal tumor.

BACKGROUND: Preoperative knowledge of mutational status of gastrointestinal stromal tumors (GISTs) is essential to guide the individualized precision therapy. AIM: To develop a combined model that integrates clinical and contrast-enhanced computed tomography (CE-CT) features to predict gastric GISTs with specific genetic mutations, namely KIT exon 11 mutations or KIT exon 11 codons 557-558 deletions. METHODS: A total of 231 GIST patients with definitive genetic phenotypes were divided into a training dataset and a validation dataset in a 7:3 ratio. The models were constructed using selected clinical features, conventional CT features, and radiomics features extracted from abdominal CE-CT images. Three models were developed: ModelCT sign, modelCT sign + rad, and model CTsign + rad + clinic. The diagnostic performance of these models was evaluated using receiver operating characteristic (ROC) curve analysis and the Delong test. RESULTS: The ROC analyses revealed that in the training cohort, the area under the curve (AUC) values for modelCT sign, modelCT sign + rad, and modelCT sign + rad + clinic for predicting KIT exon 11 mutation were 0.743, 0.818, and 0.915, respectively. In the validation cohort, the AUC values for the same models were 0.670, 0.781, and 0.811, respectively. For predicting KIT exon 11 codons 557-558 deletions, the AUC values in the training cohort were 0.667, 0.842, and 0.720 for modelCT sign, modelCT sign + rad, and modelCT sign + rad + clinic, respectively. In the validation cohort, the AUC values for the same models were 0.610, 0.782, and 0.795, respectively. Based on the decision curve analysis, it was determined that the modelCT sign + rad + clinic had clinical significance and utility. CONCLUSION: Our findings demonstrate that the combined modelCT sign + rad + clinic effectively distinguishes GISTs with KIT exon 11 mutation and KIT exon 11 codons 557-558 deletions. This combined model has the potential to be valuable in assessing the genotype of GISTs.

Univariable and multivariable Mendelian randomization study identified the key role of gut microbiota in immunotherapeutic toxicity.

BACKGROUND: In cancer patients receiving immune checkpoint inhibitors (ICIs), there is emerging evidence suggesting a correlation between gut microbiota and immune-related adverse events (irAEs). However, the exact roles of gut microbiota and the causal associations are yet to be clarified. METHODS: To investigate this, we first conducted a univariable bi-directional two-sample Mendelian randomization (MR) analysis. Instrumental variables (IVs) for gut microbiota were retrieved from the MiBioGen consortium (18,340 participants). GWAS summary data for irAEs were gathered from an ICIs-treated cohort with 1,751 cancer patients. Various MR analysis methods, including inverse variance weighted (IVW), MR PRESSO, maximum likelihood (ML), weighted median, weighted mode, and cML-MA-BIC, were used. Furthermore, multivariable MR (MVMR) analysis was performed to account for possible influencing instrumental variables. RESULTS: Our analysis identified fourteen gut bacterial taxa that were causally associated with irAEs. Notably, Lachnospiraceae was strongly associated with an increased risk of both high-grade and all-grade irAEs, even after accounting for the effect of BMI in the MVMR analysis. Akkermansia, Verrucomicrobiaceae, and Anaerostipes were found to exert protective roles in high-grade irAEs. However, Ruminiclostridium6, Coprococcus3, Collinsella, and Eubacterium (fissicatena group) were associated with a higher risk of developing high-grade irAEs. RuminococcaceaeUCG004, and DefluviitaleaceaeUCG011 were protective against all-grade irAEs, whereas Porphyromonadaceae, Roseburia, Eubacterium (brachy group), and Peptococcus were associated with an increased risk of all-grade irAEs. CONCLUSIONS: Our analysis highlights a strong causal association between Lachnospiraceae and irAEs, along with some other gut microbial taxa. These findings provide potential modifiable targets for managing irAEs and warrant further investigation.

The necessity and safety of simultaneous cholecystectomy during gastric surgery for patients with asymptomatic cholelithiasis.

OBJECTIVES: The incidence of cholelithiasis is higher among individuals who have undergone gastric surgery. The benefits of concomitant gallbladder removal in asymptomatic gallstone patients remain uncertain. The aim was to investigate the necessity and safety of simultaneous cholecystectomy in this particular patient population. METHODS: We performed a systematic review and meta-analysis to assess the incidence of asymptomatic cholelithiasis converting to symptomatic after gastric surgery and the complication rate associated with simultaneous cholecystectomy. PubMed, Embase, and the Cochrane Library were searched for relevant articles published until 10 March 202210 March 2022. RESULTS: Patients with asymptomatic cholelithiasis after gastric surgery were at a higher risk of developing symptomatic cholelithiasis compared to those without cholelithiasis (relative risk [RR] 2.28, 95% confidence interval [CI] 1.23-4.25) and those with unknown gallbladder conditions (RR 2.70, 95% CI 1.54-4.73). Additionally, patients who underwent simultaneous cholecystectomy did not face a higher risk of complications compared to those who only underwent gastric surgery (RR 0.86, 95% CI 0.48-1.53). CONCLUSIONS: Simultaneous cholecystectomy is both necessary and safe for patients with asymptomatic cholelithiasis undergoing gastric surgery. It is crucial to assess the gallbladder's condition before gastric surgery, and if the gallbladder status is unknown, simultaneous cholecystectomy should be avoided.

Evaluating the Causal Association between Inflammatory Bowel Disease and Risk of Atherosclerotic Cardiovascular Disease: Univariable and Multivariable Mendelian Randomization Study.

BACKGROUND: Observational studies suggested that inflammatory bowel disease (IBD) (i.e., Crohn's disease [CD] and ulcerative colitis [UC]) is associated with an increased risk of atherosclerotic cardiovascular disease (ASCVD), including coronary artery disease (CAD) and ischemic stroke. However, it is still unclear whether the observed associations causally exist. Thus, we aim to examine the potential effect of IBD, CD, and UC on the risk of CAD and ischemic stroke, using a two-sample Mendelian randomization (MR) study. METHODS: Genetic instruments for IBD, CD, and UC were retrieved from the latest published genome-wide association studies (GWASs) of European ancestry. GWAS summary data for instrument-outcome associations were gathered from four independent resources: CARDIoGRAMplusC4D Consortium, MEGASTROKE consortium, FinnGen, and UK Biobank. The inverse variance weighted (IVW) method and multiple pleiotropy-robust approaches were conducted and, subsequently, combined in a fixed-effect meta-analysis. Moreover, multivariable MR (MVMR) analysis was conducted to adjust for potential influencing instrumental variables. RESULTS: The IVW method revealed no causal effect of IBD on the risk of CAD (overall IBD on CAD: OR 1.003, 95%CI 0.982 to 1.025; CD on CAD: OR 0.997, 95%CI 0.978 to 1.016; UC on CAD: OR 0.986, 95%CI 0.963 to 1.010) or the risk of ischemic stroke (overall IBD on ischemic stroke: OR 0.994, 95%CI 0.970 to 1.018; CD on ischemic stroke: OR 0.996, 95%CI 0.979 to 1.014; UC on ischemic stroke: OR 0.999, 95%CI 0.978 to 1.020). The results of the meta-analysis and MVMR remained consistent. CONCLUSION: Our MR analysis does not support a causal effect of IBD on CAD and ischemic stroke, and previous results from observational studies might be biased through uncontrolled confoundings (such as IBD-specific medications and detection bias, etc.) that warrant further research.

Targeted demethylation of the SLC5A7 promotor inhibits colorectal cancer progression.

BACKGROUND: SLC5A7 (solute carrier family 5 member 7), also known as choline transporter 1 (CHT1), is downregulated in colorectal cancer (CRC) and functions as a tumor suppressor. However, the mechanisms underlying the inactivation of SLC5A7 in CRC remain to be elucidated. RESULTS: In the present study, two broad-spectrum demethylation agents (azacitidine and decitabine) employed to treat CRC cells significantly upregulated SLC5A7 expression. Further results based on the CRC cohort and TCGA database indicated that SLC5A7 promoter methylation inversely correlated with SLC5A7 expression, and the status of SLC5A7 promotor methylation showed a promising prognostic value for patients with CRC. Next, the dCas9-multiGCN4/scFv-TET1CD-based precision demethylation system was constructed, which could significantly and specifically promote SLC5A7 expression in CRC cells through sgRNA targeting the SLC5A7 promoter. Both in vitro and in vivo experiments demonstrated that targeted demethylation of SLC5A7 by dCas9-multiGCN4/scFv-TET1CD-sgSLC5A7 inhibited tumor growth by stabilizing p53 and regulating downstream targets. CONCLUSIONS: Collectively, DNA promoter methylation caused inactivation of SLC5A7 in CRC, and targeted demethylation of SLC5A7 might be a therapeutic target for CRC and other cancers.

Identification of Endoplasmic Reticulum Stress-Related Subtypes, Infiltration Analysis of Tumor Microenvironment, and Construction of a Prognostic Model in Colorectal Cancer.

Recently, endoplasmic reticulum (ER) stress has been shown to influence tumor progression and immune cell function in the tumor microenvironment (TME). However, the underlying role of ER stress-related gene patterns in colorectal cancer (CRC) development remains unclear. We analyzed the ER stress-related gene patterns in 884 patients with CRC from the Gene Expression Omnibus database and evaluated the cell-infiltrating patterns in the TME. Two ER stress-related patterns were identified in patients with CRC that had distinct cell-infiltrating patterns in the TME and clinical characteristics. A risk score and nomogram based on 14 screened prognosis-correlated genes was built and validated to predict patient survival. Patients with a higher risk score were shown to have an unfavorable prognosis, and the risk score was associated with cell infiltration and drug sensitivity. Furthermore, spatial transcriptomics data were utilized to explore ER stress-related gene patterns in CRC tissues, and it was shown that ER stress phenotype involves in the formation of the immunosuppressive TME. This study demonstrated that ER stress-related gene patterns play a role in influencing the TME and predicting prognosis. These analyses of ER stress in the TME of CRC might deepen our understanding of CRC progression and immune escape and provide novel insights into therapeutic strategies.