Evaluating research waste and traits among randomized controlled trials of scars over the past 20 years: a cross-sectional study.

PURPOSE: To analyze the changes in the characteristics of randomized controlled trials (RCTs) in the field of scarring over the last two decades, unveil the components of research waste (RW) within these RCTs, and identify targets for improvement. METHODS: A search was conducted on ClinicalTrials.gov for RCTs registered from January 2000 to December 2023, using "scar" as the keyword. The search was carried out in January 2024. RESULTS: 391 RCTs were included in this analysis. The global registration of RCTs in scarring has exhibited a consistent increase annually, with the proportion in Asia gradually rising, while the shares in North America and Europe have demonstrated a declining trend. In the analysis of RW, 232 RCTs were included, of which 96 (41.4%) have been published. Among the published RCTs, 56 (58.3%) were evaluated to have sufficient reporting, while 47 RCTs (48.9%) were identified as having avoidable design flaws. Ultimately, 183 RCTs (78.9%) exhibited at least one form of RW. Multicenter design (OR: 3.324, 95%CI: 1.385-7.975, P = 0.018), non-pharmacological interventions (OR: 2.61, 95%CI: 1.253-5.435, P = 0.010), the absence of external funding (OR: 0.325, 95%CI: 0.144-0.732, P = 0.031), and participant numbers exceeding 50 (OR: 3.269, 95%CI: 1.573-6.794, P = 0.002) were identified as independent protective factors against waste. CONCLUSIONS: This study delineates the changes in the characteristics of scar RCTs globally over the past two decades, uncovering a substantial burden of RW in scarring research. It provides an evidential reference for more rational planning of future scar-related RCTs and for minimizing RW.

KLHL21 suppresses gastric tumourigenesis via maintaining STAT3 signalling equilibrium in stomach homoeostasis.

OBJECTIVE: Precancerous metaplasia transition to dysplasia poses a risk for subsequent intestinal-type gastric adenocarcinoma. However, the molecular basis underlying the transformation from metaplastic to cancerous cells remains poorly understood. DESIGN: An integrated analysis of genes associated with metaplasia, dysplasia was conducted, verified and characterised in the gastric tissues of patients by single-cell RNA sequencing and immunostaining. Multiple mouse models, including homozygous conditional knockout Klhl21-floxed mice, were generated to investigate the role of Klhl21 deletion in stemness, DNA damage and tumour formation. Mass-spectrometry-based proteomics and ribosome sequencing were used to elucidate the underlying molecular mechanisms. RESULTS: Kelch-like protein 21 (KLHL21) expression progressively decreased in metaplasia, dysplasia and cancer. Genetic deletion of Klhl21 enhances the rapid proliferation of Mist1+ cells and their descendant cells. Klhl21 loss during metaplasia facilitates the recruitment of damaged cells into the cell cycle via STAT3 signalling. Increased STAT3 activity was confirmed in cancer cells lacking KLHL21, boosting self-renewal and tumourigenicity. Mechanistically, the loss of KLHL21 promotes PIK3CB mRNA translation by stabilising the PABPC1-eIF4G complex, subsequently causing STAT3 activation. Pharmacological STAT3 inhibition by TTI-101 elicited anticancer effects, effectively impeding the transition from metaplasia to dysplasia. In patients with gastric cancer, low levels of KLHL21 had a shorter survival rate and a worse response to adjuvant chemotherapy. CONCLUSIONS: Our findings highlighted that KLHL21 loss triggers STAT3 reactivation through PABPC1-mediated PIK3CB translational activation, and targeting STAT3 can reverse preneoplastic metaplasia in KLHL21-deficient stomachs.

Laparoscopic Spleen-Preserving Hilar Lymphadenectomy for Advanced Proximal Gastric Cancer Without Greater Curvature Invasion: Five-Year Outcomes From the Fuges-02 Randomized Clinical Trial.

Importance: Splenic hilar lymphadenectomy has been recommended for locally advanced proximal gastric cancer (APGC) involving the greater curvature. However, it is unclear whether laparoscopic spleen-preserving splenic hilar lymphadenectomy (LSPSHL) is associated with a long-term survival benefit for APGC without greater curvature invasion. Objective: To present the 5-year follow-up data from a randomized clinical trial that compared laparoscopic total gastrectomy (D2 group) with D2 plus LSPSHL (D2 + No. 10 group) among patients with resectable APGC. Design, Setting, and Participants: This is a post hoc secondary analysis of a randomized clinical trial that enrolled 536 patients with potentially resectable APGC (cT2-4a, N0 or N+, and M0) without greater curvature invasion from January 5, 2015, to October 10, 2018. All patients were tracked for at least 5 years. The final follow-up was on October 30, 2023. Interventions: Patients were randomly assigned in a 1:1 ratio to the D2 + No. 10 or D2 groups. Main Outcomes and Measures: The 5-year disease-free survival (DFS) and overall survival (OS) rates were measured. Recurrence patterns and causes of death were compared. Results: A total of 526 patients (392 men [74.5%]; mean [SD] age, 60.6 [9.6] years) were included in the modified intent-to-treat analysis, with 263 patients in each group. The 5-year DFS rate was 63.9% (95% CI, 58.1%-69.7%) for the D2 + No. 10 group and 55.1% (95% CI, 49.1%-61.1%) for the D2 group (log-rank P = .04). A statistically significant difference was observed in the 5-year OS between the D2 + No. 10 group and the D2 group (66.2% [95% CI, 60.4%-71.9%] vs 57.4% [95% CI, 51.4%-63.4%]; log-rank P = .03). The No. 10 lymph node exhibited a therapeutic value index (TVI) of 6.5, surpassing that of Nos. 8a (TVI, 3.0), 11 (TVI, 5.8), and 12a (TVI, 0.8). A total of 86 patients in the D2 + No. 10 group (cumulative incidence, 32.7%) and 111 patients in the D2 group (cumulative incidence, 42.2%) experienced recurrence (hazard ratio, 0.72; 95% CI, 0.54-0.95; P = .02). The multivariable competing risk regression model demonstrated that D2 + No. 10 remained an independent protective factor for a lower 5-year cumulative recurrence rate after surgery (hazard ratio, 0.75; 95% CI, 0.56-1.00; P = .05). There was a significant difference in the 5-year cumulative recurrence rate at the No. 10 lymph node area between the 2 groups (D2 + No. 10 group vs D2 group: 0% vs 2.3% [n = 6]; P = .01). Conclusions: This post hoc secondary analysis of a randomized clinical trial found that laparoscopic total gastrectomy with LSPSHL can improve the prognosis and reduce recurrence for APGC without greater curvature invasion. Future multicenter studies are warranted to validate these findings. Trial Registration: ClinicalTrials.gov Identifier: NCT02333721.

Circ-0075305 hinders gastric cancer stem cells by indirectly disrupting TCF4-ß-catenin complex and downregulation of SOX9.

CircRNAs are covalently closed, single-stranded RNA that form continuous loops and play a crucial role in the initiation and progression of tumors. Cancer stem cells (CSCs) are indispensable for cancer development; however, the regulation of cancer stem cell-like properties in gastric cancer (GC) and its specific mechanism remain poorly understood. We elucidate the specific role of Circ-0075305 in GC stem cell properties. Circ-0075305 associated with chemotherapy resistance was identified by sequencing GC cells. Subsequent confirmation in both GC tissues and cell lines revealed that patients with high expression of Circ-0075305 had significantly better overall survival (OS) rates than those with low expression, particularly when treated with postoperative adjuvant chemotherapy for GC. In vitro and in vivo experiments confirmed that overexpression of Circ-0075305 can effectively reduce stem cell-like properties and enhance the sensitivity of GC cells to Oxaliplatin compared with the control group. Circ-0075305 promotes RPRD1A expression by acting as a sponge for corresponding miRNAs. The addition of LF3 (a ß-catenin/TCF4 interaction antagonist) confirmed that RPRD1A inhibited the formation of the TCF4-ß-catenin transcription complex through competitive to ß-catenin and suppressed the transcriptional activity of stem cell markers such as SOX9 via the Wnt/ß-catenin signaling pathway. This leads to the downregulation of stem cell-like property-related markers in GC. This study revealed the underlying mechanisms that regulate Circ-0075305 in GCSCs and suggests that its role in reducing ß-catenin signaling may serve as a potential therapeutic candidate.

Robotic versus laparoscopic distal gastrectomy for resectable gastric cancer: a randomized phase 2 trial.

Robotic surgery may be an alternative to laparoscopic surgery for gastric cancer (GC). However, randomized controlled trials (RCTs) reporting the differences in survival between these two approaches are currently lacking. From September 2017 to January 2020, 300 patients with cT1-4a and N0/+ were enrolled and randomized to either the robotic (RDG) or laparoscopic distal gastrectomy (LDG) group (NCT03313700). The primary endpoint was 3-year disease-free survival (DFS); secondary endpoints reported here are the 3-year overall survival (OS) and recurrence patterns. The remaining secondary outcomes include intraoperative outcomes, postoperative recovery, quality of lymphadenectomy, and cost differences, which have previously been reported. There were 283 patients in the modified intention-to-treat analysis (RDG group: n = 141; LDG group: n = 142). The trial has met pre-specified endpoints. The 3-year DFS rates were 85.8% and 73.2% in the RDG and LDG groups, respectively (p = 0.011). Multivariable Cox regression model including age, tumor size, sex, ECOG PS, lymphovascular invasion, histology, pT stage, and pN stage showed that RDG was associated with better 3-year DFS (HR: 0.541; 95% CI: 0.314-0.932). The RDG also improved the 3-year cumulative recurrence rate (RDG vs. LDG: 12.1% vs. 21.1%; HR: 0.546, 95% CI: 0.302-0.990). Compared to LDG, RDG demonstrated non-inferiority in 3-year DFS rate.

Textbook oncological outcomes and prognosis after curative gastrectomy in advanced gastric cancer: A multicenter study.

BACKGROUND: The impact of achieving textbook oncological outcome (TOO) as a multimodal therapy quality indicator on the prognosis of advanced gastric cancer (AGC) remains inadequately assessed. METHODS: Patients with AGC who underwent curative gastrectomy between January 2010 and December 2017 at two East Asian medical centers were included. TOO was defined as achieving the textbook outcome (TO) and receiving neoadjuvant and/or adjuvant chemotherapy (NCT or ACT). Cox and logistic regression models were used to identify prognostic and non-TOO-associated risk factors. RESULTS: Among 3626 patients, 57.6% achieved TOO (TOO group), exhibiting significantly better 5-year overall survival (OS) and disease-free survival (DFS) than the non-TOO group (both p < 0.05). Multivariate Cox regression identified TOO as an independent prognostic factor for 5-year OS (HR, 0.67; 95% CI, 0.61-0.74; p < 0.001) and DFS (HR, 0.73; 95% CI, 0.66-0.81; p < 0.001). Multivariate logistic regression showed that open gastrectomy, lack of health insurance, age ≥65 years, ASA score ≥ Ⅲ, and tumor size ≥50 mm are independent risk factors for non-achievement of TOO (all p < 0.05). On a sensitivity analysis of TOO's prognostic value using varying definitions of chemotherapy parameters, a stricter definition of chemotherapy resulted in a decrease in the TOO achievement rate from 57.6 to 22.3%. However, the associated reductions in the risk of death and recurrence fluctuated within the ranges of 33-39% and 28-37%, respectively. CONCLUSIONS: TOO is a reliable and stable metric for favorable prognosis in AGC. Optimizing the surgical approach and improving health insurance status may enhance TOO achievement.

Assessment of Laparoscopic Indocyanine Green Tracer-guided Lymphadenectomy After Neoadjuvant Chemotherapy for Locally Advanced Gastric Cancer: A Randomized Controlled Trial.

OBJECTIVE: To assess the effectiveness of indocyanine green (ICG)-guided lymph node (LN) dissection during laparoscopic radical gastrectomy after neoadjuvant chemotherapy (NAC) in patients with locally advanced gastric cancer (LAGC). BACKGROUND: Studies on ICG imaging use in patients with LAGC on NAC are rare. METHODS: Patients with gastric adenocarcinoma (clinical T2-4NanyM0) who received NAC were randomly assigned to receive ICG-guided laparoscopic radical gastrectomy or laparoscopic radical gastrectomy alone. Here, we reported the secondary endpoints including the quality of lymphadenectomy (total retrieved LNs and LN noncompliance) and surgical outcomes. RESULTS: Overall, 240 patients were randomized. Of whom, 236 patients were included in the primary analysis (118 in the ICG group and 118 in the non-ICG group). In the ICG group, the mean number of LNs retrieved was significantly higher than in the non-ICG group within the D2 dissection (48.2 vs 38.3, P < 0.001). The ICG fluorescence guidance significantly decreased the LN noncompliance rates (33.9% vs 55.1%, P = 0.001). In 165 patients without baseline measurable LNs, ICG significantly increased the number of retrieved LNs and decreased the LN noncompliance rate ( P < 0.05). For 71 patients with baseline measurable LNs, the quality of lymphadenectomy significantly improved in those who had a complete response ( P < 0.05) but not in those who did not ( P > 0.05). Surgical outcomes were comparable between the groups ( P > 0.05). CONCLUSIONS: ICG can effectively improve the quality of lymphadenectomy in patients with LAGC who underwent laparoscopic radical gastrectomy after NAC.

Comparison of Short-term and Three-year Oncological Outcomes Between Robotic and Laparoscopic Gastrectomy for Gastric Cancer: A Large Multicenter Cohort Study.

OBJECTIVE: To compare the short-term and long-term outcomes between robotic gastrectomy (RG) and laparoscopic gastrectomy (LG) for gastric cancer. BACKGROUND: The clinical outcomes of RG over LG have not yet been effectively demonstrated. METHODS: This retrospective cohort study included 3599 patients with gastric cancer who underwent radical gastrectomy at eight high-volume hospitals in China from January 2015 to June 2019. Propensity score matching was performed between patients who received RG and LG. The primary end point was 3-year disease-free survival (DFS). RESULTS: After 1:1 propensity score matching, 1034 pairs of patients were enrolled in a balanced cohort for further analysis. The 3-year DFS in the RG and LG was 83.7% and 83.1% ( P =0.745), respectively, and the 3-year overall survival was 85.2% and 84.4%, respectively ( P =0.647). During 3 years of follow-up, 154 patients in the RG and LG groups relapsed (cumulative incidence of recurrence: 15.0% vs 15.0%, P =0.988). There was no significant difference in the recurrence sites between the 2 groups (all P >0.05). Sensitivity analysis showed that RG had comparable 3-year DFS (77.4% vs 76.7%, P =0.745) and overall survival (79.7% vs 78.4%, P =0.577) to LG in patients with advanced (pathologic T2-4a) disease, and the recurrence pattern within 3 years was also similar between the 2 groups (all P >0.05). RG had less intraoperative blood loss, lower conversion rate, and shorter hospital stays than LG (all P >0.05). CONCLUSIONS: For resectable gastric cancer, including advanced cases, RG is a safe approach with comparable 3-year oncological outcomes to LG when performed by experienced surgeons.

OSATS scoring confirms ICG enhancement of performance in laparoscopic radical gastrectomy: a post-hoc analysis of a randomized controlled trial.

BACKGROUND: Indocyanine green (ICG) fluorescence imaging is effective in increasing the number of lymph node dissections during laparoscopic radical gastrectomy; however, no studies have attempted to explain this phenomenon. METHODS: This study utilized the data from a previous randomized controlled trial (FUGES-012 study) investigating ICG-guided laparoscopic radical gastrectomy performed between November 2018 and July 2019. The Objective Structured Assessments of Technical Skills (OSATS) scoring system was used to grade videos from the ICG and non-ICG groups. Patients with an OSATS score greater than 29 were classified as the high-OSATS population, while those with an OSATS score less than or equal to 29 were classified as the low-OSATS population. RESULTS: A total of 258 patients were included in the modified intention-to-treat analysis: 129 in the ICG group and 129 in the non-ICG group. The OSATS score of the ICG group was higher than that of the non-ICG group (29.6±2.6 vs. 26.6±3.6; P <0.001). The ICG group underwent a significantly higher mean total number of lymph node dissections than the non-ICG group (50.5±15.9 vs. 42.0±10.3; adjusted P <0.001). The group assigned to ICG use, better OSATS (high-OSATS) scores were observed, which correlated with greater D2 lymph node retrieval (54.1±15.0 vs. 47.2±8.7; adjusted P =0.039). Finally, the ICG group had a lower rate of lymph node noncompliance than that of the non-ICG group (31.8 vs. 57.4%; P <0.001). CONCLUSIONS: By applying the ICG fluorescence navigation technique, better OSATS scores were observed, which correlated with greater lymph node retrieval and a lower lymph node noncompliance rate, as recommended for individualized laparoscopic radical gastrectomy.

Characterization changes and research waste in randomized controlled trials of global bariatric surgery over the past 20 years: cross-sectional study.

BACKGROUND: The results of several large randomized controlled trials (RCTs) have changed the clinical practice of bariatric surgery. However, the characteristics of global RCTs of bariatric surgery have not been reported internationally and whether there was research waste in these RCTs is unknown. METHODS: Search ClinicalTrials.gov for bariatric surgery RCTs registered between January 2000 and December 2022 with the keywords 'Roux-en-Y gastric-bypass' and 'Sleeve Gastrectomy'. The above analysis was conducted in January 2023. RESULTS: A total of 326 RCTs were included in this study. The number of RCTs registered for sleeve gastrectomy and gastric bypass surgery increased year by year globally. Europe has always accounted for the largest proportion, Asia has gradually increased, and North America has decreased. A total of 171 RCTs were included in the analysis of waste, of which 74 (43.8%) were published. Of the 74 published RCTs, 37 (37/74, 50.0%) were judged to be adequately reported and 36 (36/74, 48.6%) were judged to have avoidable design defects. In the end, 143 RCTs (143/171, 83.6%) had at least one research waste. Body weight change as the primary endpoint (OR: 0.266, 95% CI: 0.103-0.687, P =0.006) and enrolment greater than 100 (OR: 0.349, 95% CI: 0.146-0.832, P =0.018) were independent protective factors for research waste. CONCLUSIONS: This study for the first time describes the characteristic changes of the mainstream RCT of bariatric surgery globally in the last 20 years and identifies a high research waste burden and predictive factor in this area, which provides reference evidence for carrying out bariatric surgery RCTs more rationally.

Neurotransmitter Receptor HTR2B Regulates Lipid Metabolism to Inhibit Ferroptosis in Gastric Cancer.

Nerves can support tumor development by secreting neurotransmitters that promote cancer cell proliferation and invasion. 5-Hydroxytryptamine (5-HT) is a critical neurotransmitter in the gastrointestinal nervous system, and 5-HT signaling has been shown to play a role in tumorigenesis. Here, we found that expression of the 5-HT receptor HTR2B was significantly elevated in human gastric adenocarcinoma tissues compared with nontumor tissues, and high HTR2B expression corresponded to shorter patient survival. Both 5-HT and a specific HTR2B agonist enhanced gastric adenocarcinoma cell viability under metabolic stress, reduced cellular and lipid reactive oxygen species, and suppressed ferroptosis; conversely, HTR2B loss or inhibition with a selective HTR2B antagonist yielded the inverse tumor suppressive effects. In a patient-derived xenograft tumor model, HTR2B-positive tumors displayed accelerated growth, which was inhibited by HTR2B antagonists. Single-cell analysis of human gastric adenocarcinoma tissues revealed enrichment of PI3K/Akt/mTOR and fatty acid metabolism-related gene clusters in cells expressing HTR2B compared with HTR2B-negative cells. Mechanistically, HTR2B cooperated with Fyn to directly regulate p85 activity and trigger the PI3K/Akt/mTOR signaling pathway, which led to increased expression of HIF1α and ABCD1 along with decreased levels of lipid peroxidation and ferroptosis. Together, these findings demonstrate that HTR2B activity modulates PI3K/Akt/mTOR signaling to stimulate gastric cancer cell survival and indicate that HTR2B expression could be a potential prognostic biomarker in patients with gastric cancer. SIGNIFICANCE: Nerve cancer cross-talk mediated by HTR2B inhibits lipid peroxidation and ferroptosis in gastric cancer cells and promotes viability under metabolic stress, resulting in increased tumor growth and decreased patient survival.

Indocyanine green fluorescence imaging-guided versus conventional laparoscopic lymphadenectomy for gastric cancer: long-term outcomes of a phase 3 randomised clinical trial.

Indocyanine green (ICG) fluorescence imaging-guided lymphadenectomy has been demonstrated to be effective in increasing the number of lymph nodes (LNs) retrieved in laparoscopic gastrectomy for gastric cancer (GC). Previously, we reported the primary outcomes and short-term secondary outcomes of a phase 3, open-label, randomized clinical trial (NCT03050879) investigating the use of ICG for image-guided lymphadenectomy in patients with potentially resectable GC. Patients were randomly (1:1 ratio) assigned to either the ICG or non-ICG group. The primary outcome was the number of LNs retrieved and has been reported. Here, we report the primary outcome and long-term secondary outcomes including three-year overall survival (OS), three-year disease-free survival (DFS), and recurrence patterns. The per-protocol analysis set population is used for all analyses (258 patients, ICG [n = 129] vs. non-ICG group [n = 129]). The mean total LNs retrieved in the ICG group significantly exceeds that in the non-ICG group (50.5 ± 15.9 vs 42.0 ± 10.3, P < 0.001). Both OS and DFS in the ICG group are significantly better than that in the non-ICG group (log-rank P = 0.015; log-rank P = 0.012, respectively). There is a difference in the overall recurrence rates between the ICG and non-ICG groups (17.8% vs 31.0%). Compared with conventional lymphadenectomy, ICG guided laparoscopic lymphadenectomy is safe and effective in prolonging survival among patients with resectable GC.

CDK5 promotes apoptosis and attenuates chemoresistance in gastric cancer via E2F1 signaling.

BACKGROUND: Chemoresistance is a major clinical challenge that leads to tumor metastasis and poor clinical outcome. The mechanisms underlying gastric cancer resistance to chemotherapy are still unclear. METHODS: We conducted bioinformatics analyses of publicly available patient datasets to establish an apoptotic phenotype and determine the key pathways and clinical significance. In vitro cell models, in vivo mouse models, and numerous molecular assays, including western blotting, qRT-PCR, immunohistochemical staining, and coimmunoprecipitation assays were used to clarify the role of factors related to apoptosis in gastric cancer in this study. Differences between datasets were analyzed using the Student's t-test and two-way ANOVA; survival rates were estimated based on Kaplan-Meier analysis; and univariate and multivariate Cox proportional hazards models were used to evaluate prognostic factors. RESULTS: Bulk transcriptomic analysis of gastric cancer samples established an apoptotic phenotype. Proapoptotic tumors were enriched for DNA repair and immune inflammatory signaling and associated with improved prognosis and chemotherapeutic benefits. Functionally, cyclin-dependent kinase 5 (CDK5) promoted apoptosis of gastric cancer cells and sensitized cells and mice to oxaliplatin. Mechanistically, we demonstrate that CDK5 stabilizes DP1 through direct binding to DP1 and subsequent activation of E2F1 signaling. Clinicopathological analysis indicated that CDK5 depletion correlated with poor prognosis and chemoresistance in human gastric tumors. CONCLUSION: Our findings reveal that CDK5 promotes cell apoptosis by stabilizing DP1 and activating E2F1 signaling, suggesting its potential role in the prognosis and therapeutic decisions for patients with gastric cancer.

A scoring model for predicting early recurrence of gastric cancer with normal preoperative tumor markers: A multicenter study.

INTRODUCTION: Prognostic factors for postoperative early recurrence (ER) of gastric cancer (GC) in patients with normal or abnormal preoperative tumor markers (pre-TMs) remain unclear. MATERIALS AND METHODS: 2875 consecutive patients with GC who underwent radical gastrectomy (RG) between January 2010 and December 2016 were enrolled and randomly divided into training and internal validation groups. ER was defined as recurrence within two years of gastrectomy. Normal pre-TMs were defined as CEA≤5 ng/mL and CA199 ≤ 37 U/mL. Least absolute shrinkage selection operator (LASSO) Cox regression analysis was used to screen ER predictors. The scoring model was validated using 546 patients from another hospital. RESULTS: A total of 3421 patients were included. Multivariate Cox analysis showed that pre-TMs was an independent prognostic factor for ER. Survival after ER was equally poor in the normal and abnormal pre-TMs groups (P = 0.160). Based on LASSO Cox regression, the ER of patients with abnormal pre-TMs was only associated with the pT and pN stages; however, in patients with normal pre-TMs, it was also associated with tumor size, perineural invasion, and prognostic nutritional index. Scoring model constructed for patients with normal pre-TMs had better predictive performance than TNM staging (concordance-index:0.826 vs. 0.807, P < 0.001) and good reproducibility in both validation sets. Moreover, through risk stratification, the scoring model could not only identify the risk of ER but also distinguish ER patterns and adjuvant chemotherapy benefit subgroups. CONCLUSION: pre-TMs is an independent prognostic factor for ER in GC after RG. The established scoring model demonstrates excellent predictive performance and clinical utility.

Loss of ATOH1 in Pit Cell Drives Stemness and Progression of Gastric Adenocarcinoma by Activating AKT/mTOR Signaling through GAS1.

Gastric cancer stem cells (GCSCs) are self-renewing tumor cells that govern chemoresistance in gastric adenocarcinoma (GAC), whereas their regulatory mechanisms remain elusive. Here, the study aims to elucidate the role of ATOH1 in the maintenance of GCSCs. The preclinical model and GAC sample analysis indicate that ATOH1 deficiency is correlated with poor GAC prognosis and chemoresistance. ScRNA-seq reveals that ATOH1 is downregulated in the pit cells of GAC compared with those in paracarcinoma samples. Lineage tracing reveals that Atoh1 deletion strongly confers pit cell stemness. ATOH1 depletion significantly accelerates cancer stemness and chemoresistance in Tff1-CreERT2; Rosa26Tdtomato and Tff1-CreERT2; Apcfl/fl ; p53fl/fl (TcPP) mouse models and organoids. ATOH1 deficiency downregulates growth arrest-specific protein 1 (GAS1) by suppressing GAS1 promoter transcription. GAS1 forms a complex with RET, which inhibits Tyr1062 phosphorylation, and consequently activates the RET/AKT/mTOR signaling pathway by ATOH1 deficiency. Combining chemotherapy with drugs targeting AKT/mTOR signaling can overcome ATOH1 deficiency-induced chemoresistance. Moreover, it is confirmed that abnormal DNA hypermethylation induces ATOH1 deficiency. Taken together, the results demonstrate that ATOH1 loss promotes cancer stemness through the ATOH1/GAS1/RET/AKT/mTOR signaling pathway in GAC, thus providing a potential therapeutic strategy for AKT/mTOR inhibitors in GAC patients with ATOH1 deficiency.

Long-term prognostic benefit of adjuvant chemotherapy for patients with hepatoid adenocarcinoma of the stomach after radical resection: A national multicenter study.

BACKGROUND: There is no consensus on whether adjuvant chemotherapy (AC) is effective for hepatoid adenocarcinoma of the stomach (HAS). The aim of this study was to investigate the relationship between AC and the long-term prognosis of patients with HAS. METHODS: The clinicopathological data of 239 patients with primary HAS who underwent radical surgery from April 1, 2004 to December 31, 2019 in 14 centers in China were retrospectively analyzed. Patients were divided into the AC group (127 patients) and the nonadjuvant chemotherapy (NAC) group (112 patients). RESULTS: Kaplan‒Meier (KM) analysis showed that there were no significant differences in the 1-year3-year overall survival rate (OS) and 1-year, 3-year recurrence-free survival rate (RFS) between the AC group and the NAC group (1-year OS: 85.6% vs. 79.8%, 3-year OS: 59.8% vs. 62.4%, 1-year RFS: 69.8% vs. 74.4%, 3-year RFS: 57.2% vs. 55.9%, all P > 0.05). The subpopulation treatment effect pattern plots (STEPP) did not show treatment heterogeneity of AC in patients with HAS. The proportions of local recurrence and metastasis sites in the two groups were similar. Although the smoothed hazard curves of the NAC and AC groups crossed, the peak hazard time was later in the AC group (5.9 and 4.7 months), and the peak hazard rate was lower (0.032 and 0.038, P = 0.987). CONCLUSION: The current AC regimen may not significantly improve the survival of patients with HAS after radical surgery.

AND-Gated Nanosensor for Imaging of Glutathione and Apyrimidinic Endonuclease 1 in Cells, Animals, and Organoids.

The development of a strategy for imaging of glutathione (GSH) and apurinic/apyrimidinic endonuclease 1 (APE1) in an organism remains challenging despite their significance in elaborating the correlated pathophysiological processes. Therefore, in this study, we propose a DNA-based AND-gated nanosensor for fluorescence imaging of the GSH as well as APE1 in living cells, animals, and organoids. The DNA probe is composed of a G-strand and A-strand. The disulfide bond in the G-strand is cleaved through a GSH redox reaction, and the hybridization stability between the G-strand and A-strand is decreased, leading to a conformational change of the A-strand. In the presence of APE1, the apurinic/apyrimidinic (AP) site in the A-strand is digested, producing a fluorescence signal for the correlated imaging of GSH and APE1. This nanosensor enables monitoring of the expression level change of GSH and APE1 in cells. Additionally, we illustrate the capability of this "dual-keys-and-locked" conceptual methodology in achieving specific tumor imaging when GSH and APE1 are present simultaneously (overexpressed GSH and APE1 in tumor cells) with improving tumor-to-normal tissue ratio in vivo. Furthermore, using this nanosensor, the GSH and APE1 also are visualized in organoids that recapitulate the phenotypic and functional traits of the original biological specimens. Overall, this study demonstrates the potential of our proposed biosensing technology in investigating the roles of various biological molecules involved in specific diseases.

A multiparametric fluorescent visualization approach for detecting drug resistance in living cancer cells.

Drug resistance is a worldwide health care crisis which impedes disease treatment and increases financial burden, especially for its multifactorial nature and high complexity. Herein, we developed a multiparametric approach to visualize and detect drug resistance in living cancer cells, through the combination of DNA-templated covalent protein labeling strategy and fluorescent resonance energy transfer technique. Gefitinib resistance in non-small cell lung cancer caused by mesenchymal-epidermal transition factor (Met) overexpression and hyperactivation was investigated as a proof-of-concept. Unlike the traditional single-factor investigation, the proposed approach evaluated the contribution of three important parameters towards the resistance, including the changes of Met expression level, the homodimerization of Met with itself and the heterodimerization of Met with epidermal growth factor receptor (EGFR). A multiple regression model based on these three parameters was tentatively established for evaluation of the resistance level of laboratory-developed resistant cells and evaluation of the resistance level of patient-derived cells. Such an approach facilitates a quick identification of a drug resistance, to evaluate not only the resistance level but also the resistance mechanism.

SOX9 Modulates the Transformation of Gastric Stem Cells Through Biased Symmetric Cell Division.

BACKGROUND & AIMS: Transformation of stem/progenitor cells has been associated with tumorigenesis in multiple tissues, but stem cells in the stomach have been hard to localize. We therefore aimed to use a combination of several markers to better target oncogenes to gastric stem cells and understand their behavior in the initial stages of gastric tumorigenesis. METHODS: Mouse models of gastric metaplasia and cancer by targeting stem/progenitor cells were generated and analyzed with techniques including reanalysis of single-cell RNA sequencing and immunostaining. Gastric cancer cell organoids were genetically manipulated with clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) for functional studies. Cell division was determined by bromodeoxyuridine-chasing assay and the assessment of the orientation of the mitotic spindles. Gastric tissues from patients were examined by histopathology and immunostaining. RESULTS: Oncogenic insults lead to expansion of SOX9+ progenitor cells in the mouse stomach. Genetic lineage tracing and organoid culture studies show that SOX9+ gastric epithelial cells overlap with SOX2+ progenitors and include stem cells that can self-renew and differentiate to generate all gastric epithelial cells. Moreover, oncogenic targeting of SOX9+SOX2+ cells leads to invasive gastric cancer in our novel mouse model (Sox2-CreERT;Sox9-loxp(66)-rtTA-T2A-Flpo-IRES-loxp(71);Kras(Frt-STOP-Frt-G12D);P53R172H), which combines Cre-loxp and Flippase-Frt genetic recombination systems. Sox9 deletion impedes the expansion of gastric progenitor cells and blocks neoplasia after Kras activation. Although Sox9 is not required for maintaining tissue homeostasis where asymmetric division predominates, loss of Sox9 in the setting of Kras activation leads to reduced symmetric cell division and effectively attenuates the Kras-dependent expansion of stem/progenitor cells. Similarly, Sox9 deletion in gastric cancer organoids reduces symmetric cell division, organoid number, and organoid size. In patients with gastric cancer, high levels of SOX9 are associated with recurrence and poor prognosis. CONCLUSION: SOX9 marks gastric stem cells and modulates biased symmetric cell division, which appears to be required for the malignant transformation of gastric stem cells.