Abstract Background Disruption of host–microbiota homeostasis is a fundamental hallmark of inflammatory bowel disease (IBD) pathogenesis. Host epigenetic modifications and corresponding alterations in gene expression levels can impact the composition of gut microbes. SET domain containing 2 (SETD2) is a critical epigenetic regulator with established tumor‐suppressive roles, but its function in intestinal microbial ecology and colitis progression remains unexplored. We aimed to investigate the specific role of SETD2 in maintaining gut microbial homeostasis and modulating colitis progression. Methods RNA sequencing (RNA‐seq), assay for transposase‐accessible chromatin with high‐throughput sequencing (ATAC‐seq) and cleavage under targets and tagmentation sequencing (CUT&Tag‐seq) were conducted on colonic epithelial cells from intestinal epithelial cell‐specific SETD2 knockout (Setd2vil‐ko) mice to identify key mediators contributing to colitis development. Faecal samples underwent 16S rRNA sequencing and non‐targeted metabolomics analysis to characterise microbial dysbiosis and metabolic perturbations. Molecular experiments and faecal microbiome transplantation experiment were conducted to explore and validate the role of SETD2 in colitis development. Results SETD2 deficiency induced overproduction of Reg3 lectins and disrupted gut microbiota composition. Beneficial commensal bacteria were depleted and dysregulated metabolites were accumulated in Setd2vil‐ko mice. Supplementation with healthy‐like gut microbiota significantly ameliorated the exacerbated colitis induced by SETD2 deficiency. ConclusionsOur findings uncover a previously unrecognised role for SETD2 in maintaining microbial homeostasis, offering new mechanistic insights into how epigenetic regulation preserves intestinal homeostasis and suggesting novel therapeutic avenues for IBD.

As an emerging branch of clinical medicine, microbiota medicine has attracted worldwide attention from clinicians, medical educators, patient communities, and industry. However, this developing field still lacks consensus on its fundamental principles as well as guidelines for clinical and educational practice. An expert panel was convened by the journal Microbiota Medicine Research at the 2025 CHINAGUT Conference to develop the principles and practice guidelines of microbiota medicine using the Delphi method. This document provides a new framework for clinicians, educational institutions, and healthcare administrators. The expert panel developed 15 key statements, encompassing definitions of microbiota medicine and dysbiosis-related diseases, graded value evaluation of microbiome testing technologies, pathways for multidisciplinary discussions on complex dysbiosis-related diseases, and educational frameworks for physicians in microbiota medicine. The panel further recommends incorporating microbiota medicine into undergraduate and postgraduate medical education and emphasizes the application of artificial intelligence in supporting microbiota medicine. This guideline defines core competencies required for physicians specializing in this discipline. Collectively, this guideline aims to define the significant role of microbiota medicine in clinical practice and medical education, thereby advancing its sustainable development.

INTRODUCTION:KRAS mutations are prevalent in pancreatic ductal adenocarcinoma (PDAC), colorectal cancer (CRC) and non-small-cell lung cancer (NSCLC), characterized by poor outcomes due to limited therapies and drug resistance. Histone deacetylase inhibitors (HDACi) are effective in hematological malignancies but show limited efficacy against solid tumors with unknown mechanism, significantly restricting their clinical applications. OBJECTIVES:This study aimed to evaluate the efficacy of class I HDACi in KRAS-mutant cancers, particularly in overcoming KRAS inhibitor (KRASi) resistance, and to elucidate the associated mechanisms. METHODS:The effects of class I HDACi on tumor growth and metastasis, alone or combined with KRAS/MAPK inhibitors, were assessed in KRAS-mutant tumor models. Transcriptome and acetylome analyses were used to identify key effectors, while cell functional assays like flow cytometry, chromatin immunoprecipitation, and immunofluorescence explored how class I HDACi induced cell death and combated KRASi resistance. RESULTS:Class I HDACi, especially the novel inhibitor IHCH9033, demonstrated desirable pharmacokinetic properties and strong efficacy in various KRAS-mutant tumor xenografts. Mechanistically, class I HDACi induced p53 acetylation, restoring its wild-type function, and c-Myc acetylation, promoting its proteasomal degradation, collectively leading to oxidative stress, DNA damage and apoptosis. Further study illustrated the regulatory effect of p53 on YAP/TAZ activity. Critically, IHCH9033 surmounted KRASi resistance by suppressing YAP-c-Myc axis while also acting synergistically with KRAS/MAPK inhibitors to repress MAPK and other oncogenic signaling. This combination robustly enhanced tumor suppression in both KRASi-sensitive and -resistant cell xenografts, including a KRASG12C-mutant CRC patient-derived xenograft model. Notably, IHCH9033 exhibited brain bioavailability and reduced metastatic progression in a NSCLC brain metastasis model and an orthotopic PDAC model by blocking the YAP-TGF-β crosstalk. CONCLUSION:Targeting class I HDACs, alone or combined with KRAS/MAPK inhibitors, represents a promising therapeutic strategy that concurrently disrupts both epigenetic and oncogenic pathways to treat KRAS-mutant cancers and overcome resistance, warranting clinical evaluation.

The programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) pathway, a pivotal immune checkpoint, enables tumor immune evasion, and its blockade is fundamental to cancer immunotherapy. The development of small-molecule agents targeting the PD-1/PD-L1 pathway offers a promising strategy for enhancing antitumor immunity. In this study, we screened an in-house compound library using RKO cells to discover novel PD-L1 downregulators. MS1-96 was identified as a potent PD-L1 degrader that promotes lysosome-dependent PD-L1 degradation. Furthermore, MS1-96 effectively reduced PD-L1 protein levels across multiple colorectal cancer (CRC) cell lines. By disrupting the PD-1/PD-L1 pathway, MS1-96 enhances CD8+ T cell-mediated killing of carcinoma cells and exerts dose-dependent antitumor effects in C57BL/6 mice bearing MC38 CRC xenografts, resulting in significant tumor growth inhibition after oral administration for 10 d (100, 200, or 400 mg·kg⁻¹·d⁻¹). Mechanistic studies revealed that Huntingtin interacting protein 1-related (HIP1R) plays an indispensable role in MS1-96-driven PD-L1 degradation, and HIP1R knockdown abolishes MS1-96’s ability to degrade PD-L1. MS1-96 directly binds to PD-L1 with a KD of 2.58 μM and enhances the interaction between HIP1R and PD-L1, thereby altering the intracellular trafficking of PD-L1 within clathrin-coated vesicles. This leads to reduced transport of PD-L1 to recycling endosomes and increased delivery to late endosomes and lysosomes for degradation. Furthermore, MS1-96 induces abnormal N-glycosylation of PD-L1, destabilizing the protein and hastening its lysosome-mediated degradation. Moreover, MS1-96 effectively enhances the antitumor efficacy of PD-1 antibodies in MC38 CRC models. These findings indicate that MS1-96 offers a potential strategy for advancing tumor immunotherapy.

Although tumor-associated macrophages (TAMs) play a critical immunomodulatory role in colorectal cancer (CRC), the mechanisms underlying their polarization remain unclear. This study identifies the P2X4 receptor (P2X4R) as a crucial mediator of M1-like polarization. During TAM induction in a controlled in vitro system using CRC cell-conditioned medium, we observed P2X4R-mediated calcium influx and subsequent mitochondrial dysfunction through immunofluorescence and mitochondrial assays. This dysfunction led to mitochondrial DNA release and subsequent activation of the cGAS-STING-IFNB1 pathway, driving M1-like polarization of TAMs. Flow cytometry demonstrated that P2X4R-expressing TAMs not only enhanced CD8+ T cell survival and cytotoxicity in vitro but also augmented T cell responses in a syngeneic CRC mouse model. Clinically, reduced P2X4 expression in CRC tissues correlated with poorer prognosis. In conclusion, these findings identify the P2X4R as a key regulator of M1-like TAM polarization, representing a promising target to reprogram TAMs and suppress CRC progression.

BACKGROUND:Aurora kinase B (AURKB), a key regulator of mitosis, is frequently upregulated in various malignancies, including colorectal cancer (CRC), and is associated with poor prognosis. However, the limited clinical efficacy of AURKB inhibitors suggests the existence of previously unrecognized oncogenic mechanisms that merit further investigation. METHODS:AURKB was prioritized through bioinformatic analysis, and its elevated expression in CRC was validated via single-cell RNA sequencing (scRNA-seq) and western blot. The transcriptional activation of AURKB was attributed to H3K18 lactylation, as confirmed by chromatin immunoprecipitation (ChIP)-qPCR. RNA sequencing (RNA-seq) and gene set enrichment analysis (GSEA) were conducted to pinpoint the downstream targets of AURKB. The role of the AURKB/phosphoserine aminotransferase 1 (PSAT1) axis in CRC was further studied using both in vitro and in vivo functional experiments. Mass spectrometry, co-immunoprecipitation (Co-IP), proximity ligation assay (PLA), RNA immunoprecipitation (RIP)-qPCR, and mRNA stability assays were employed to investigate the interplay and potential mechanisms involving AURKB, heterogeneous nuclear ribonucleoprotein M (HNRNPM), and PSAT1. RESULTS:AURKB was identified as an oncogene linked to advanced pathological staging and poor clinical outcomes in CRC. Its transcriptional upregulation was driven by H3K18 lactylation at its promoter. PSAT1 was further identified as a key downstream effector in AURKB-mediated CRC progression. Mechanistically, AURKB bound to HNRNPM and interfered with its interaction with PSAT1 mRNA, thereby suppressing HNRNPM-mediated mRNA degradation and ultimately increasing PSAT1 protein levels. CONCLUSION:Our findings uncover a previously unappreciated, kinase-independent function of AURKB in CRC, redefining its therapeutic relevance beyond kinase inhibition. This highlights the need for broader targeting strategies, including PROTAC-mediated degradation of AURKB and pharmacological inhibition of the AURKB/PSAT1 axis, to fully harness its role in CRC treatment.

Background:The indications for percutaneous endoscopic gastrostomy (PEG) in oral cancer patients remain unclear. This study aimed to analyze the relevant clinical characteristics of oral cancer surgical patients undergoing PEG. Methods:Clinical data of oral cancer patients who underwent PEG from July 2020 to June 2021 at Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine were collected. Patients with PEG usage exceeding 1 month were assigned to the case group, while those with PEG usage equal to or less than 1 month were assigned to the control group. Univariate analysis and logistic regression analysis were employed to identify independent factors influencing the differential usage of PEG and the predictive value of relevant factors was assessed using receiver operating characteristic (ROC) curve analysis. Results:A total of 104 cases of oral cancer surgical patients undergoing PEG were included. Univariate analysis revealed significant effects of tongue/pharyngeal resection during surgery (P=0.03), postoperative combined radiotherapy and chemotherapy (P=0.002), as well as advanced tumor stage (T stage) (P<0.001) and node stage (N stage) (P<0.001) of oral cancer on PEG usage. Logistic regression analysis identified postoperative combined radiotherapy and chemotherapy, T stage, and N stage as independent factors influencing PEG usage. The combined predictive model yielded an area under the ROC curve (AUC) of 0.832 (P<0.001), with sensitivity and specificity of 0.767 and 0.778, respectively. Conclusions:The results suggest that oral cancer patients with tongue/pharyngeal resection during surgery, postoperative combined radiotherapy and chemotherapy, and advanced T and N stages of oral cancer may have a stronger indication for PEG.

Background & Aims: Direct-acting antivirals (DAAs) have considerably improved chronic hepatitis C (HCV) treatment; however, follow-up after sustained virological response (SVR) typically neglects the risk of liver-related events (LREs). This study introduces and validates the artificial intelligence-safe score (AI-Safe-C score) to assess the risk of LREs in patients without cirrhosis after successful DAA treatment. Methods: The random survival forest model was trained to predict LREs in 913 patients without cirrhosis after SVR in Korea and was further tested in a combined cohort from Hong Kong and France (n = 1,264). The model's performance was assessed using Harrell's C-index and the area under the time-dependent receiver-operating characteristic curve (AUROC). Results: The AI-Safe-C score, which incorporated liver stiffness measurement (LSM), age, sex, and six other biochemical tests - with LSM being ranked as the most important among nine clinical features - demonstrated a C-index of 0.86 (95% CI 0.82-0.90) in predicting LREs in an external validation cohort. It achieved 3- and 5-year LRE AUROCs of 0.88 (95% CI 0.84-0.92) and 0.79 (95% CI 0.71-0.87), respectively, and for hepatocellular carcinoma, a C-index of 0.87 (95% CI 0.81-0.92) with 3- and 5-year AUROCs of 0.88 (95% CI 0.84-0.93) and 0.82 (95% CI 0.75-0.90), respectively. Using a cut-off of 0.7, the 5-year LRE rate within a high-risk group was between 3.2% and 6.2%, mirroring the incidence observed in individuals with advanced fibrosis, in stark contrast to the significantly lower incidence of 0.2% to 0.6% in a low-risk group. Conclusion: The AI-Safe-C score is a useful tool for identifying patients without cirrhosis who are at higher risk of developing LREs. The post-SVR LSM, as integrated within the AI-Safe-C score, plays a critical role in predicting future LREs. (c) 2024 European Association for the Study of the Liver. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Disrupting DNA replication has been employed for treating cancers. In the present study, we found that Tripartite motif containing 21 (TRIM21) was highly expressed in colorectal cancer (CRC) and could be valuable for predicting the prognosis of CRC patients. Further study demonstrated that TRIM21 positively regulated the expression of MCM2 and MCM5, DNA replication and proliferation of CRC cells both in vitro and in vivo. In addition, TRIM21 knockdown inhibited both replication initiation and velocity, and increased the chemosensitivity of CRC cells to 5-FU and SN-38. Our study also revealed that DNA replication inhibition following TRIM21 knockdown could not be restored by cell cycle checkpoint kinase inhibitors, but partially by Transcription Factor 3 (TCF3) knockdown. TCF3 directly suppressed MCM2 and MCM5 transcription, inhibiting DNA replication. In summary, TRIM21 could influence tumor development and chemosensitivity to replication inhibitors by regulating DNA replication through the TCF3/MCM2/5 axis, suggesting a promising potential for CRC in the clinic.

Gastric cancer (GC) remains a leading cause of cancer-related mortality worldwide. The prognosis for advanced GC is poor, necessitating innovative therapeutic strategies. Small interfering RNA (siRNA) offers a promising avenue for gene-specific cancer treatment. However, effective delivery of siRNA remains a challenge. Chitosan, a natural biopolymer, has demonstrated potential as a nanocarrier due to its biocompatibility and ability to facilitate targeted delivery. This study investigates the therapeutic efficacy of a novel chitosan-RNU11 siRNA drug delivery system in inhibiting GC progression and elucidates its underlying mechanisms. Chitosan nanoparticles (CH-NP) loaded with RNU11 siRNA (Si-RNU11 + CH-NP) were synthesized and characterized for size, zeta potential, and siRNA release efficiency. GC cell lines (AGS and HGC27) were treated with various formulations, and functional assays, including EdU proliferation, Transwell invasion/migration, and cell cycle/apoptosis analysis, were conducted. The in vivo efficacy of Si-RNU11 + CH-NP was evaluated in GC xenograft mouse models. Expression of Wnt pathway components was analyzed by Western blot and qRT-PCR. Si-RNU11 + CH-NP exhibited a uniform size distribution ( 85 μm) with a zeta potential of + 14 mV, ensuring colloidal stability and efficient cellular uptake. siRNA release exceeded 95

The emergence of 16S rRNA and metagenomic sequencing has gradually revealed the close relationship between dysbiosis and colorectal cancer (CRC). Recent studies have confirmed that intestinal dysbiosis plays various roles in the occurrence, development, and therapeutic response of CRC. Perturbation of host immunity is one of the key mechanisms involved. The intestinal microbiota, or specific bacteria and their metabolites, can modulate the progression of CRC through pathogen recognition receptor signaling or via the recruitment, polarization, and activation of both innate and adaptive immune cells to reshape the protumor/antitumor microenvironment. Therefore, the administration of gut bacteria to enhance immune homeostasis represents a new strategy for the treatment of CRC. In this review, we cover recent studies that illuminate the role of gut bacteria in the progression and treatment of CRC through orchestrating the immune response, which potentially offers insights for subsequent transformative research.

OBJECTIVE:Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy because it is often diagnosed at a late-stage. Signal transducer and activator of transcription 5 (STAT5) is a transcription factor implicated in the progression of various cancer types. However, its role in KRAS-driven pancreatic tumourigenesis remains unclear. DESIGN:We performed studies with LSL-Kras G12D; Ptf1a-Cre ERT (KCERT) mice or LSL-KrasG12D; LSL-Trp53R172H ; Pdx1-Cre (KPC) mice crossed with conditional disruption of STAT5 or completed deficiency interleukin (IL)-22. Pancreatitis was induced in mice by administration of cerulein. Pharmacological inhibition of STAT5 on PDAC prevention was studied in the orthotopic transplantation and patient-derived xenografts PDAC model, and KPC mice. RESULTS:The expression and phosphorylation of STAT5 were higher in human PDAC samples than control samples and high levels of STAT5 in tumour cells were associated with a poorer prognosis. The loss of STAT5 in pancreatic cells substantially reduces the KRAS mutation and pancreatitis-derived acinar-to-ductal metaplasia (ADM) and PDAC lesions. Mechanistically, we discovered that STAT5 binds directly to the promoters of ADM mediators, hepatocyte nuclear factor (HNF) 1β and HNF4α. Furthermore, STAT5 plays a crucial role in maintaining energy metabolism in tumour cells during PDAC progression. IL-22 signalling induced by chronic inflammation enhances KRAS-mutant-mediated STAT5 phosphorylation. Deficiency of IL-22 signalling slowed the progression of PDAC and ablated STAT5 activation. CONCLUSION:Collectively, our findings identified pancreatic STAT5 activation as a key downstream effector of oncogenic KRAS signalling that is critical for ADM initiation and PDAC progression, highlighting its potential therapeutic vulnerability.

BACKGROUND:Inflammatory bowel disease (IBD) presents a significant challenge due to its intricate pathogenesis. NSD2, a histone methyltransferase responsible for dimethylating histone 3 at lysine 36, is associated with transcriptional activation. NSD2 expression is decreased in both the intestinal epithelial cells (IECs) of IBD patients and the IBD mouse model. However, the precise role of NSD2 in IBD remains unexplored. METHODS:Colon tissues from IBD mice, SW620 cells and MC38 cells, were used as research subjects. Clinical databases of IBD patients were analysed to investigate whether NSD2 expression is reduced in the occurrence of IBD. NSD2-knockout mice were generated to further investigate the role of NSD2 in IBD. The IECs were isolated for RNA sequencing and chromatin immunoprecipitation sequencing to identify molecular signalling pathways and key molecules leading to IBD in mice. Molecular and cellular experiments were conducted to analyse and validate the role of NSD2 in the development of IBD. Finally, rescue experiments were performed to confirm the molecular mechanism of NSD2 in the development of IBD. RESULTS:Deficiency of NSD2 in mouse IECs aggravated epithelial barrier disruption and inflammatory response in IBD. Mechanistically, NSD2 loss led to downregulation of H3K36me2 and flavin-containing monooxygenase (FMO) (taurine-synthesis enzyme) mRNA, resulting in decreased taurine biosynthesis in IECs. Significantly, supplementation with taurine markedly alleviated the symptoms of NSD2 deficiency-induced IBD. CONCLUSIONS:These data demonstrate that NSD2 plays a pivotal role in maintaining FMO-mediated taurine biosynthesis to prevent intestinal inflammation. Our findings also underscore the importance of NSD2-H3K36me2-mediated taurine biosynthesis in maintaining intestinal mucosal barrier homeostasis. KEY POINTS:In this study, we investigated the role of the histone methyltransferase NSD2 in preventing intestinal barrier disruption by sustaining taurine biosynthesis. NSD2 levels were reduced in both human specimens and mouse models of IBD. We demonstrate that NSD2 loss hinders the process of taurine synthesis in intestinal cells, leading to increased intestinal inflammation. Supplementation with taurine significantly relieved the symptoms caused by NSD2 deficiency. These data suggest that maintenance of NSD2-mediated taurine biosynthesis is vital for preserving the intestinal barrier and attenuating inflammation.

Objective: To investigate the clinical potential and safety of Moluodan to reverse gastric precancerous lesions. Methods: Patients aged 18-70 years diagnosed with moderate-to-severe atrophy and/or moderate-to-severe intestinal metaplasia, with or without low-grade dysplasia, and negative for Helicobacter pylori were recruited in this randomized, double-blind, parallel-controlled trial. The primary outcome was the improvement of global histological diagnosis at 1-year follow-up endoscopy using the operative link for gastritis assessment, the operative link for gastric intestinal metaplasia assessment, and the disappearance rate of dysplasia. Results: Between November 3, 2017 and January 27, 2021, 166 subjects were randomly assigned to the Moluodan group, 168 to the folic acid group, 84 to the combination group, and 84 to the high-dose Moluodan group. The improvement in global histological diagnosis was achieved in 60 (39.5%) subjects receiving Moluodan, 59 (37.8%) receiving folic acid, 26 (32.1%) receiving the combined drugs, and 36 (47.4%) receiving high-dose Moluodan. Moluodan was non-inferior to folic acid (95% confidence interval: -9.2 to 12.5; P = 0.02). High-dose Moluodan had a trend for better protective efficacy, though there was no statistical significance. The disappearance rate of dysplasia was 82.8% in the Moluodan group, which was superior to folic acid (53.9%; P = 0.006). No drug-related serious adverse events were observed. Conclusions: One pack of Moluodan three times daily for 1 year was safe and effective in reversing gastric precancerous lesions, especially dysplasia. Doubling its dose showed a better efficacy trend.

BackgroundFor decades, KRAS has always been a huge challenge to the field of drug discovery for its significance in cancer progression as well as its difficulties in being targeted as an "undruggable" protein. KRAS regulates downstream signaling pathways through protein-protein interactions, whereas many interaction partners of KRAS remain unknown.ResultsWe developed a workflow to computationally predict and experimentally validate the potential KRAS-interacting proteins based on the interaction mode of KRAS and its known binding partners. We extracted 17 KRAS-interacting motifs from all experimentally determined KRAS-containing protein complexes as queries to identify proteins containing fragments structurally similar to the queries in the human protein structure database using our in-house protein-protein interaction prediction method, PPI-Miner. Finally, out of the 78 predicted potential interacting proteins of KRAS, 10 were selected for experimental validation, including BRAF, a previously reported interacting protein, which served as the positive control in our validation experiments. Additionally, a known peptide that binds to KRAS, KRpep-2d, was also used as a positive control. The predicted interacting motifs of these 10 proteins were synthesized to perform biolayer interferometry assays, with 4 out of 10 exhibiting binding affinities to KRAS, and the strongest, GRB10, was selected for further validation. Additionally, the interaction between GRB10 (RA-PH domain) and KRAS was confirmed via immunofluorescence and co-immunoprecipitation.ConclusionsThese results demonstrate the effectiveness of our workflow in predicting potential interacting proteins for KRAS and deepen the understanding of KRAS-driven tumor mechanisms and the development of therapeutic strategies.

Importance:Probiotic supplementation may improve bowel movements. However, large, properly designed studies are lacking. Objective:To evaluate the potential benefit of Bifidobacterium animalis subsp lactis HN019 on constipation, expressed as complete spontaneous bowel movements (CSBMs). Design, Setting, and Participants:This randomized triple-blind placebo-controlled clinical trial with 2 weeks of run-in and 8 weeks of intervention was conducted from December 25, 2020, to February 28, 2022, at 5 hospitals in Shanghai, China. Participants included healthy volunteers with functional constipation according to Rome III criteria, 18 to 70 years of age, and a body mass index (calculated as the weight in kilograms divided by the height in meters squared) of less than 30.0. Eligibility after the run-in phase required the randomized participants to have 3 or fewer CSBMs/wk. Data were analyzed from September 29, 2022, to March 23, 2023, and reported as intention to treat. Intervention:Participants were randomized to receive probiotic (B lactis HN019, 7.0 × 109 colony forming units (CFU)/d in maltodextrin at the start of the study and 4.69 × 109 CFU/d at the end of the study or maltodextrin placebo once a day for 8 weeks. Main Outcomes and Measures:Primary outcome was change in CSBMs. Secondary outcomes included use of rescue medication, stool consistency, degree of straining for each bowel movement, abdominal pain, and bloating. Further, dietary habits and physical activity were recorded. Fecal samples were analyzed for moisture content, short-chain fatty acids, branched-chain fatty acids, microbiota composition, and calprotectin. Results:Of the 283 individuals assessed for eligibility, 229 were randomized to either the placebo (n = 117) or the HN019 (n = 112) group. One participant in the placebo group discontinued due to COVID-19 restrictions. The 229 participants (194 [84.7% female) had a median age of 45 (38-52) years, mean (SD) BMI of 22.8 (2.5), and a mean (SD) of 0.77 (1.0) CSBM/wk. There was no difference in the change of weekly CSBMs from baseline to the end of study between the HN019 (least-square mean change, 0.80 [95% CI, 0.54-1.05]) and placebo (least-square mean change, 0.66 [95% CI, 0.41-0.90]) groups. Conclusions and Relevance:Although probiotics have been reported to improve bowel function, this large, well-conducted randomized clinical trial did not confirm such results. Daily consumption of B lactis HN019 at the tested dose of 4.69 × 109 CFU did not outperform placebo to increase CSBMs. Trial Registration:Chinese Clinical Trial Registry Identifier: ChiCTR2000029215.

The frequency of p53 mutations in colorectal cancer (CRC) is approximately 40-50%. A variety of therapies are being developed to target tumors expressing mutant p53. However, potential therapeutic targets for CRC expressing wild-type p53 are rare. In this study, we show that METTL14 is transcriptionally activated by wild-type p53 and suppresses tumor growth only in p53-wild-type (p53-WT) CRC cells. METTL14 deletion promotes both AOM/DSS and AOM-induced CRC growth in mouse models with the intestinal epithelial cell-specific knockout of METTL14. Additionally, METTL14 restrains aerobic glycolysis in p53-WT CRC, by repressing SLC2A3 and PGAM1 expression via selectively promoting m6 A-YTHDF2-dependent pri-miR-6769b/pri-miR-499a processing. Biosynthetic mature miR-6769b-3p and miR-499a-3p decrease SLC2A3 and PGAM1 levels, respectively, and suppress malignant phenotypes. Clinically, METTL14 only acts as a beneficial prognosis factor for the overall survival of p53-WT CRC patients. These results uncover a new mechanism for METTL14 inactivation in tumors and, most importantly, reveal that the activation of METTL14 is a critical mechanism for p53-dependent cancer growth inhibition, which could be targeted for therapy in p53-WT CRC.