BCAA-producing Clostridium symbiosum promotes colorectal tumorigenesis through the modulation of host cholesterol metabolism.

Identification of potential bacterial players in colorectal tumorigenesis has been a focus of intense research. Herein, we find that Clostridium symbiosum (C. symbiosum) is selectively enriched in tumor tissues of patients with colorectal cancer (CRC) and associated with higher colorectal adenoma recurrence after endoscopic polypectomy. The tumorigenic effect of C. symbiosum is observed in multiple murine models. Single-cell transcriptome profiling along with functional assays demonstrates that C. symbiosum promotes the proliferation of colonic stem cells and enhances cancer stemness. Mechanistically, C. symbiosum intensifies cellular cholesterol synthesis by producing branched-chain amino acids (BCAAs), which sequentially activates Sonic hedgehog signaling. Low dietary BCAA intake or blockade of cholesterol synthesis by statins could partially abrogate the C. symbiosum-induced cell proliferation in vivo and in vitro. Collectively, we reveal C. symbiosum as a bacterial driver of colorectal tumorigenesis, thus identifying a potential target in CRC prediction, prevention, and treatment.

The road to a world-unified approach to the management of patients with gastric intestinal metaplasia: a review of current guidelines.

OBJECTIVE: During the last decade, the management of gastric intestinal metaplasia (GIM) has been addressed by several distinct international evidence-based guidelines. In this review, we aimed to synthesise these guidelines and provide clinicians with a global perspective of the current recommendations for managing patients with GIM, as well as highlight evidence gaps that need to be addressed with future research. DESIGN: We conducted a systematic review of the literature for guidelines and consensus statements published between January 2010 and February 2023 that address the diagnosis and management of GIM. RESULTS: From 426 manuscripts identified, 15 guidelines were assessed. There was consistency across guidelines regarding the purpose of endoscopic surveillance of GIM, which is to identify prevalent neoplastic lesions and stage gastric preneoplastic conditions. The guidelines also agreed that only patients with high-risk GIM phenotypes (eg, corpus-extended GIM, OLGIM stages III/IV, incomplete GIM subtype), persistent refractory Helicobacter pylori infection or first-degree family history of gastric cancer should undergo regular-interval endoscopic surveillance. In contrast, low-risk phenotypes, which comprise most patients with GIM, do not require surveillance. Not all guidelines are aligned on histological staging systems. If surveillance is indicated, most guidelines recommend a 3-year interval, but there is some variability. All guidelines recommend H. pylori eradication as the only non-endoscopic intervention for gastric cancer prevention, while some offer additional recommendations regarding lifestyle modifications. While most guidelines allude to the importance of high-quality endoscopy for endoscopic surveillance, few detail important metrics apart from stating that a systematic gastric biopsy protocol should be followed. Notably, most guidelines comment on the role of endoscopy for gastric cancer screening and detection of gastric precancerous conditions, but with high heterogeneity, limited guidance regarding implementation, and lack of robust evidence. CONCLUSION: Despite heterogeneous populations and practices, international guidelines are generally aligned on the importance of GIM as a precancerous condition and the need for a risk-stratified approach to endoscopic surveillance, as well as H. pylori eradication when present. There is room for harmonisation of guidelines regarding (1) which populations merit index endoscopic screening for gastric cancer and GIM detection/staging; (2) objective metrics for high-quality endoscopy; (3) consensus on the need for histological staging and (4) non-endoscopic interventions for gastric cancer prevention apart from H. pylori eradication alone. Robust studies, ideally in the form of randomised trials, are needed to bridge the ample evidence gaps that exist.

The adhesin RadD enhances Fusobacterium nucleatum tumour colonization and colorectal carcinogenesis.

Fusobacterium nucleatum can bind to host cells and potentiate intestinal tumorigenesis. Here we used a genome-wide screen to identify an adhesin, RadD, which facilitates the attachment of F. nucleatum to colorectal cancer (CRC) cells in vitro. RadD directly binds to CD147, a receptor overexpressed on CRC cell surfaces, which initiated a PI3K-AKT-NF-κB-MMP9 cascade, subsequently enhancing tumorigenesis in mice. Clinical specimen analysis showed that elevated radD gene levels in CRC tissues correlated positively with activated oncogenic signalling and poor patient outcomes. Finally, blockade of the interaction between RadD and CD147 in mice effectively impaired F. nucleatum attachment and attenuated F. nucleatum-induced oncogenic response. Together, our study provides insights into an oncogenic mechanism driven by F. nucleatum RadD and suggests that the RadD-CD147 interaction could be a potential therapeutic target for CRC.

The effects of air and transportation noise pollution-related altered blood gene expression, DNA methylation, and protein abundance levels on gastrointestinal diseases risk.

INTRODUCTION: Air pollution and transportation noise pollution has been linked to gastrointestinal (GI) diseases, but their relationship remains unclear. METHODS: We extracted the significantly modulated genes and CpG sites related to air pollution (PM2.5, PM10, and NOx) and transportation noise pollution (aircraft, railway, and traffic road noise) from previous published studies. Genome-wide methylation analysis and colocalization analysis with these CpG sites and GWAS data of GI diseases were performed to disentangle the relationship between pollution-related blood DNA methylation (DNAm) alterations and GI diseases risk. Summary-based Mendelian randomization (SMR) analysis assessed the impact of pollution-related genes on GI diseases risk across methylation, gene expression, and protein levels. Enrichment analysis investigated the implicated biological pathways and immune cell types. RESULTS: DNAm at cg00227781 [CD300A] (modulated by NOx exposure) and cg19215199 [ZMIZ1] (modulated by PM2.5 exposure) was significantly linked to increased noninfective enteritis and colitis risk, while cg08500171 [BAT2] (modulated by NOx exposure) is significantly associated with an increased gastroesophageal reflux disease (GERD) risk. Colocalization analysis provides strong evidence supporting a shared causal variant between these associations. Multi-omics levels SMR analysis revealed that pollution-modulated lower DNAm at 5 specific CpG sites were associated with increased expression of 4 genes (IL21R, EVPL, SYNGR1, and WDR46), subsequently increasing the risk of GERD, ulcerative colitis, and gastric ulcer. 7 circulating proteins coded by pollution-modulated genes were observed to be associated with 6 GI diseases risk. Enrichment analysis implicates immune and inflammatory responses, MAPK signaling, and telomere maintenance in these pollution-induced effects. CONCLUSION: We identified potential links between air and transportation noise pollution-related gene methylation, expression, and protein abundance with GI diseases risk, possibly revealing new therapeutic targets.

A specific enterotype derived from gut microbiome of older individuals enables favorable responses to immune checkpoint blockade therapy.

Immunotherapy has revolutionized cancer treatment, but inconsistent responses persist. Our study delves into the intriguing phenomenon of enhanced immunotherapy sensitivity in older individuals with cancers. Through a meta-analysis encompassing 25 small-to-mid-sized trials of immune checkpoint blockade (ICB), we demonstrate that older individuals exhibit heightened responsiveness to ICB therapy. To understand the underlying mechanism, we reanalyze single-cell RNA sequencing (scRNA-seq) data from multiple studies and unveil distinct upregulation of exhausted and cytotoxic T cell markers within the tumor microenvironment (TME) of older patients. Recognizing the potential role of gut microbiota in modulating the efficacy of immunotherapy, we identify an aging-enriched enterotype linked to improved immunotherapy outcomes in older patients. Fecal microbiota transplantation experiments in mice confirm the therapeutic potential of the aging-enriched enterotype, enhancing treatment sensitivity and reshaping the TME. Our discoveries confront the prevailing paradox and provide encouraging paths for tailoring cancer immunotherapy strategies according to an individual's gut microbiome profile.

Fusobacterium nucleatum induces chemoresistance in colorectal cancer by inhibiting pyroptosis via the Hippo pathway.

Chemotherapy resistance is one of the main reasons for the poor prognosis of colorectal cancer (CRC). Moreover, dysbiosis of gut bacteria was found to be a specific environmental risk factor. In this study, enrichment of F. nucleatum was elucidated to be significantly associated with CRC recurrence after chemotherapy. Functional experiments showed that F. nucleatum could inhibit pyroptosis induced by chemotherapy drugs, thereby inducing chemoresistance. Furthermore, mechanistic investigation demonstrated that F. nucleatum could regulate the Hippo pathway and promote the expression of BCL2, thereby inhibiting the Caspase-3/GSDME pyroptosis-related pathway induced by chemotherapy drugs and mediating CRC cell chemoresistance. Taken together, these results validated the significant roles of F. nucleatum in CRC chemoresistance, which provided an innovative theoretical basis for the clinical diagnosis and therapy of CRC.

Effectiveness and safety of Moluodan in the treatment of precancerous lesions of gastric cancer: A randomized clinical trial.

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.

A toolbox for genetic manipulation in intestinal Clostridium symbiosum.

Gut microbes are closely related with human health, but remain much to learn. Clostridium symbiosum is a conditionally pathogenic human gut bacterium and regarded as a potential biomarker for early diagnosis of intestinal tumors. However, the absence of an efficient toolbox that allows diverse genetic manipulations of this bacterium limits its in-depth studies. Here, we obtained the complete genome sequence of C. symbiosum ATCC 14940, a representative strain of C. symbiosum. On this basis, we further developed a series of genetic manipulation methods for this bacterium. Firstly, following the identification of a functional replicon pBP1 in C. symbiosum ATCC 14940, a highly efficient conjugative DNA transfer method was established, enabling the rapid introduction of exogenous plasmids into cells. Next, we constructed a dual-plasmid CRISPR/Cas12a system for genome editing in this bacterium, reaching over 60 % repression for most of the chosen genes as well as efficient deletion (>90 %) of three target genes. Finally, this toolbox was used for the identification of crucial functional genes, involving growth, synthesis of important metabolites, and virulence of C. symbiosum ATCC 14940. Our work has effectively established and optimized genome editing methods in intestinal C. symbiosum, thereby providing strong support for further basic and application research in this bacterium.

The effects of pks+ Escherichia coli and bile acid in colorectal tumorigenesis among people with cholelithiasis or cholecystectomy.

BACKGROUND AND AIM: Patients with cholelithiasis (CL) or cholecystectomy (CE) would have more chances of getting colorectal adenoma (CRA) or cancer (CRC). We aimed to figure out the effects of gut microbiota and bile acid on colorectal neoplasm in CL and CE patients. METHODS: This was a retrospective observational study that recruited 514 volunteers, including 199 people with normal gallbladders (normal), 152 CL, and 163 CE patients. Discovery cohort was established to explore the difference in gut microbiota through 16S rRNA and metagenomics sequencing. Validation cohort aimed to verify the results through quantitative polymerase chain reaction (qPCR). RESULTS: Significant enrichment of Escherichia coli was found in patients with cholelithiasis or cholecystectomy both in the discovery cohort (16S rRNA sequencing, PNormal-CL = 0.013, PNormal-CE = 0.042; metagenomics sequencing, PNormal-CE = 0.026) and validation cohort (PNormal-CL < 0.0001, PNormal-CE < 0.0001). Pks+ E. coli was found enriched in CL and CE patients through qPCR (in discovery cohort: PNormal-CE = 0.018; in validation cohort: PNormal-CL < 0.0001, PNormal-CE < 0.0001). The differences in bile acid metabolism were found both through Tax4Fun analysis of 16S rRNA sequencing (Ko00120, primary bile acid biosynthesis, PNormal-CE = 0.014; Ko00121, secondary bile acid biosynthesis, PNormal-CE = 0.010) and through metagenomics sequencing (map 00121, PNormal-CE = 0.026). The elevation of serum total bile acid of CE patients was also found in validation cohort (PNormal-CE < 0.0001). The level of serum total bile acid was associated with the relative abundance of pks+ E. coli (r = 0.1895, P = 0.0012). CONCLUSIONS: E. coli, especially pks+ species, was enriched in CL and CE patients. Pks+ E. coli and bile acid metabolism were found associated with CRA and CRC in people after cholecystectomy.

Metabolic syndrome, its components, and gastrointestinal cancer risk: a meta-analysis of 31 prospective cohorts and Mendelian randomization study.

BACKGROUND AND AIM: Cohort studies have linked metabolic syndrome (MetS) to gastrointestinal (GI) cancer risk. We aimed to evaluate the associations between MetS, its components, and combinations of MetS components with eight GI cancers risk. METHODS: We conducted a systematic search of prospective cohort studies and performed a meta-analysis. Subgroup analyses regarding diagnostic criteria, sex, cancer sites, histological subtypes, ethnic groups, and studies adjusted for alcohol consumption were carried out. Mendelian randomization (MR) was employed to evaluate the causality between 17 MetS-related traits and eight GI cancers among Europeans and Asians separately. RESULTS: Meta-analyses of 31 prospective studies indicated that MetS was significantly associated with an increased risk of colorectal cancer (CRC) (RR [95% CI] = 1.13 [1.12-1.15]), esophageal cancer (EC) (RR [95% CI] = 1.17 [1.03-1.32]), gallbladder cancer (GBC) (RR [95% CI] = 1.37[1.10-1.71]), liver cancer (LC) (RR [95% CI] = 1.46 [1.29-1.64]), and pancreatic cancer (PaC) (RR [95% CI] = 1.25 [1.20-1.30]), but not gastric cancer (GC) (RR [95% CI] = 1.11 [0.96-1.28]). Regarding the associations between MetS components and GI cancers risk, the following associations showed statistical significance: obesity-CRC/LC/EC/, hypertriglyceridemia-LC/PaC, reduced high-density lipoprotein (HDL)-CRC/LC/GC/PaC, hyperglycemia-CRC/LC/PaC, and hypertension-CRC/LC/EC/PaC. Sex-specific associations were observed between individual MetS components on GI cancers risk. Among the top three common combinations in both sexes, obesity + HTN + hyperglycemia had the strongest association with CRC risk (RR [95% CI] = 1.54 [1.49-1.61] for males and 1.27 [1.21-1.33] for females). MR analyses revealed causality in 16 exposure-outcome pairs: waist-to-hip ratio/BMI/HbA1c-CRC; BMI/childhood obesity/waist circumference/T2DM/glucose-EC; BMI/waist circumference/cholesterol-LC; cholesterol/childhood obesity/waist circumference/HbA1c-PaC; and HbA1c-GBC. These results were robust against sensitivity analyses. CONCLUSIONS: Since MetS is reversible, lifestyle changes or medical interventions targeting MetS patients might be potential prevention strategies for GI cancers.

Deficiency of BCAT2-mediated branched-chain amino acid catabolism promotes colorectal cancer development.

OBJECTIVE: Branched-chain amino acid (BCAA) metabolism is involved in the development of colorectal cancer (CRC); however, the underlying mechanism remains unclear. Therefore, this study investigates the role of BCAA metabolism in CRC progression. METHODS: Dietary BCAA was administered to both azoxymethane-induced and azoxymethane/dextran sodium sulfate-induced CRC mouse models. The expression of genes related to BCAA metabolism was determined using RNA sequencing. Adjacent tissue samples, obtained from 58 patients with CRC, were subjected to quantitative real-time PCR and immunohistochemical analysis. Moreover, the suppressive role of branched-chain aminotransferase 2 (BCAT2) in cell proliferation, apoptosis, and xenograft mouse models was investigated. Alterations in BCAAs and activation of downstream pathways were also assessed using metabolic analysis and western blotting. RESULTS: High levels of dietary BCAA intake promoted CRC tumorigenesis in chemical-induced CRC and xenograft mouse models. Both the mRNA and protein levels of BCAT2 were decreased in tumor tissues of patients with CRC compared to those in normal tissues. Proliferation assays and xenograft models confirmed the suppressive role of BCAT2 in CRC progression. Furthermore, the accumulation of BCAAs caused by BCAT2 deficiency facilitated the chronic activation of mTORC1, thereby mediating the oncogenic effect of BCAAs. CONCLUSION: BCAT2 deficiency promotes CRC progression through inhibition of BCAAs metabolism and chronic activation of mTORC1.

Disruption of CerS6-mediated sphingolipid metabolism by FTO deficiency aggravates ulcerative colitis.

BACKGROUND AND AIMS: Deregulation of RNA N6-methyladenosine (m6A) modification in intestinal epithelial cells (IECs) influences intestinal immune cells and leads to intestinal inflammation. We studied the function of fat mass-and obesity-associated protein (FTO), one of the m6A demethylases, in patients with ulcerative colitis (UC). METHODS: We analysed colon tissues of Ftoflox/flox; Villin-cre mice and their Ftoflox/flox littermates with dextran sulfate sodium (DSS) using real-time PCR and 16s rRNA sequencing. RNA and methylated RNA immunoprecipitation sequencing were used to analyse immunocytes and IECs. Macrophages were treated with conditioned medium of FTO-knockdown MODE-K cells or sphingosine-1-phosphate (S1P) and analysed for gene expression. Liquid chromatograph mass spectrometry identified C16-ceramide. RESULTS: FTO downregulation was identified in our in-house cohort and external cohorts of UC patients. Dysbiosis of gut microbiota, increased infiltration of proinflammatory macrophages, and enhanced differentiation of Th17 cells were observed in Ftoflox/flox;Villin-cre mice under DSS treatment. FTO deficiency resulted in an increase in m6A modification and a decrease in mRNA stability of CerS6, the gene encoding ceramide synthetase, leading to the downregulation of CerS6 and the accumulation of S1P in IECs. Subsequentially, the secretion of S1P by IECs triggered proinflammatory macrophages to secrete serum amyloid A protein 1/3, ultimately inducing Th17 cell differentiation. In addition, through bioinformatic analysis and experimental validation, we identified UC patients with lower FTO expression might respond better to vedolizumab treatment. CONCLUSIONS: FTO downregulation promoted UC by decreasing CerS6 expression, leading to increased S1P accumulation in IECs and aggravating colitis via m6A-dependent mechanisms. Lower FTO expression in UC patients may enhance their response to vedolizumab treatment.

CHEK2 deficiency increase the response to PD-1 inhibitors by affecting the tumor immune microenvironment.

Immune checkpoint blockade (ICB) therapy has improved treatment effects in multiple cancers. Gene mutations in the DNA damage repair pathway (DDR) may cause genomic instability and may relate to the efficacy of ICB. Checkpoint kinase 2 (CHEK2) and polymerase epsilon (POLE) are important genes in the DDR. In this study, we aimed to study the impact of CHEK2 deficiency mutations on the response to ICB. We found that tumors with CHEK2 mutations had a significantly higher tumor mutational burden (TMB) compared to those with CHEK2-WT in a pancancer database. We noted that CHEK2 deficiency mutations potentiated the anti-tumor effect of anti-PD-1 therapy in MC38 and B16 tumor-bearing mice with the decrease of tumor volume and tumor weight after anti-PD-1 treatment. Mechanistically, CHEK2 deficiency tumors were with the increased cytotoxic CD8+ T-cell infiltration, especially cytotoxic CD8+ T cells, and modulated the tumor-immune microenvironment with an upregulated immune inflammatory pathway and antigen presentation pathway after anti-PD-1 treatment. Furthermore, murine models with POLE mutations confirmed that CHEK2 deficiency shaped similar mutational and immune landscapes as POLE mutations after anti-PD-1 treatment. Taken together, our results demonstrated that CHEK2 deficiency mutations may increase the response to ICB (eg. anti-PD-1) by influencing the tumor immune microenvironment. This indicated that CHEK2 deficiency mutations were a potentially predictive biomarker and CHEK2 deficiency may potentiate response to immunotherapy.

Identification of FtfL as a novel target of berberine in intestinal bacteria.

BACKGROUND: Berberine (BBR) is a commonly used anti-intestinal inflammation drug, and its anti-cancer activity has been found recently. BBR can intervene and control malignant colorectal cancer (CRC) through intestinal microbes, but the direct molecular target and related mechanism are unclear. This study aimed to identify the target of BBR and dissect related mechanisms against the occurrence and development of CRC from the perspective of intestinal microorganisms. RESULTS: Here, we found that BBR inhibits the growth of several CRC-driving bacteria, especially Peptostreptococcus anaerobius. By using a biotin-conjugated BBR derivative, we identified the protein FtfL (formate tetrahydrofolate ligase), a key enzyme in C1 metabolism, is the molecular target of BBR in P. anaerobius. BBR exhibits strong binding affinity and potent inhibition on FtfL. Based on this, we determined the crystal structure of PaFtfL (P. anaerobius FtfL)-BBR complex and found that BBR can not only interfere with the conformational flexibility of PaFtfL tetramer by wedging the tetramer interface but also compete with its substrate ATP for binding within the active center. In addition, the enzymatic activities of FtfL homologous proteins in human tumor cells can also be inhibited by BBR. CONCLUSIONS: In summary, our study has identified FtfL as a direct target of BBR and uncovered molecular mechanisms involved in the anti-CRC of BBR. BBR interferes with intestinal pathogenic bacteria by targeting FtfLs, suggesting a new means for controlling the occurrence and development of CRC.

STAT3 palmitoylation initiates a positive feedback loop that promotes the malignancy of hepatocellular carcinoma cells in mice.

Constitutive activation of the transcription factor STAT3 (signal transducer and activator of transcription 3) contributes to the malignancy of many cancers such as hepatocellular carcinoma (HCC) and is associated with poor prognosis. STAT3 activity is increased by the reversible palmitoylation of Cys108 by the palmitoyltransferase DHHC7 (encoded by ZDHHC7). Here, we investigated the consequences of S-palmitoylation of STAT3 in HCC. Increased ZDHHC7 abundance in HCC cases was associated with poor prognosis, as revealed by bioinformatics analysis of patient data. In HepG2 cells in vitro, DHHC7-mediated palmitoylation enhanced the expression of STAT3 target genes, including HIF1A, which encodes the hypoxia-inducible transcription factor HIF1α. Inhibiting DHHC7 decreased the S-palmitoylation of STAT3 and decreased HIF1α abundance. Furthermore, stabilization of HIF1α by cyclin-dependent kinase 5 (CDK5) enabled it to promote the expression of ZDHHC7, which generated a positive feedback loop between DHHC7, STAT3, and HIF1α. Perturbing this loop reduced the growth of HCC cells in vivo. Moreover, DHHC7, STAT3, and HIF1α were all abundant in human HCC tissues. Our study identifies a pathway connecting these proteins that is initiated by S-palmitoylation, which may be broadly applicable to understanding the role of this modification in cancer.

Microbiome and metabolome features in inflammatory bowel disease via multi-omics integration analyses across cohorts.

The perturbations of the gut microbiota and metabolites are closely associated with the progression of inflammatory bowel disease (IBD). However, inconsistent findings across studies impede a comprehensive understanding of their roles in IBD and their potential as reliable diagnostic biomarkers. To address this challenge, here we comprehensively analyze 9 metagenomic and 4 metabolomics cohorts of IBD from different populations. Through cross-cohort integrative analysis (CCIA), we identify a consistent characteristic of commensal gut microbiota. Especially, three bacteria, namely Asaccharobacter celatus, Gemmiger formicilis, and Erysipelatoclostridium ramosum, which are rarely reported in IBD. Metagenomic functional analysis reveals that essential gene of Two-component system pathway, linked to fecal calprotectin, are implicated in IBD. Metabolomics analysis shows 36 identified metabolites with significant differences, while the roles of these metabolites in IBD are still unknown. To further elucidate the relationship between gut microbiota and metabolites, we construct multi-omics biological correlation (MOBC) maps, which highlights gut microbial biotransformation deficiencies and significant alterations in aminoacyl-tRNA synthetases. Finally, we identify multi-omics biomarkers for IBD diagnosis, validated across multiple global cohorts (AUROC values ranging from 0.92 to 0.98). Our results offer valuable insights and a significant resource for developing mechanistic hypotheses on host-microbiome interactions in IBD.

Discovery of New Fusobacterium nucleatum Inhibitors to Attenuate Migratory Capability of Colon Cancer Cells by the Drug Repositioning Strategy.

Recent studies revealed that intestinal microbiota played important roles in colorectal cancer (CRC) carcinogenesis. Particularly, Fusobacterium nucleatum was confirmed to promote the proliferation and metastasis of CRC. Therefore, targeting F. nucleatum may be a potential preventive and therapeutic approach for CRC. Herein, 2,272 off-patent drugs were screened inhibitory activity against F. nucleatum. Among the hits, nitisinone was identified as a promising anti-F. nucleatum lead compound. Further optimization of nitisinone led to the discovery of more potent derivatives. Particularly, compounds 19q and 22c showed potent anti-F. nucleatum activity (MIC50 = 1 and 2 µg/mL, respectively) with low cytotoxicity. Among them, compound 19q effectively attenuated the migratory ability of MC-38 cells induced by F. nucleatum. Preliminary mechanism studies suggested that nitisinone and its derivatives might act by downregulating nitroreductase and tryptophanase. Thus, the development of small molecule F. nucleatum inhibitors represents an effective strategy to treat CRC.