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Gastroenterology Dec 2023Pien Tze Huang (PZH) is a well-established traditional medicine with beneficial effects against inflammation and cancer. We aimed to explore the chemopreventive effect...
BACKGROUND & AIMS
Pien Tze Huang (PZH) is a well-established traditional medicine with beneficial effects against inflammation and cancer. We aimed to explore the chemopreventive effect of PZH in colorectal cancer (CRC) through modulating gut microbiota.
METHODS
CRC mouse models were established by azoxymethane plus dextran sulfate sodium treatment or in Apc mice treated with or without PZH (270 mg/kg and 540 mg/kg). Gut barrier function was determined by means of intestinal permeability assays and transmission electron microscopy. Fecal microbiota and metabolites were analyzed by means of metagenomic sequencing and liquid chromatography mass spectrometry, respectively. Germ-free mice or antibiotic-treated mice were used as models of microbiota depletion.
RESULTS
PZH inhibited colorectal tumorigenesis in azoxymethane plus dextran sulfate sodium-treated mice and in Apc mice in a dose-dependent manner. PZH treatment altered the gut microbiota profile, with an increased abundance of probiotics Pseudobutyrivibrio xylanivorans and Eubacterium limosum, while pathogenic bacteria Aeromonas veronii, Campylobacter jejuni, Collinsella aerofaciens, and Peptoniphilus harei were depleted. In addition, PZH increased beneficial metabolites taurine and hypotaurine, bile acids, and unsaturated fatty acids, and significantly restored gut barrier function. Transcriptomic profiling revealed that PZH inhibited PI3K-Akt, interleukin-17, tumor necrosis factor, and cytokine-chemokine signaling. Notably, the chemopreventive effect of PZH involved both microbiota-dependent and -independent mechanisms. Fecal microbiota transplantation from PZH-treated mice to germ-free mice partly recapitulated the chemopreventive effects of PZH. PZH components ginsenoside-F2 and ginsenoside-Re demonstrated inhibitory effects on CRC cells and primary organoids, and PZH also inhibited tumorigenesis in azoxymethane plus dextran sulfate sodium-treated germ-free mice.
CONCLUSIONS
PZH manipulated gut microbiota and metabolites toward a more favorable profile, improved gut barrier function, and suppressed oncogenic and pro-inflammatory pathways, thereby suppressing colorectal carcinogenesis.
Topics: Mice; Animals; Signal Transduction; Gastrointestinal Microbiome; Dextran Sulfate; Phosphatidylinositol 3-Kinases; Apoptosis; Medicine, Traditional; Colorectal Neoplasms; Carcinogenesis; Azoxymethane
PubMed: 37704113
DOI: 10.1053/j.gastro.2023.08.052 -
Gut Aug 2023The role of N-methyladenosine (mA) in tumour immune microenvironment (TIME) remains understudied. Here, we elucidate function and mechanism of YTH N-methyladenosine RNA...
OBJECTIVE
The role of N-methyladenosine (mA) in tumour immune microenvironment (TIME) remains understudied. Here, we elucidate function and mechanism of YTH N-methyladenosine RNA binding protein 1 (YTHDF1) in colorectal cancer (CRC) TIME.
DESIGN
Clinical significance of YTHDF1 was assessed in tissue microarrays (N=408) and TCGA (N=526) cohorts. function was determined in syngeneic tumours, intestine-specific knockin mice, and humanised mice. Single-cell RNA-seq (scRNA-seq) was employed to profile TIME. Methylated RNA immunoprecipitation sequencing (MeRIP-seq), RNA sequencing (RNA-seq) and ribosome sequencing (Ribo-seq) were used to identify YTHDF1 direct targets. Vesicle-like nanoparticles (VNPs)-encapsulated -siRNA was used for silencing in vivo.
RESULTS
expression negatively correlated with interferon-γ gene signature in TCGA-CRC. Concordantly, YTHDF1 protein negatively correlated with CD8 T-cell infiltration in independent tissue microarrays cohorts, implying its role in TIME. Genetic depletion of augmented antitumour immunity in CT26 (MSS-CRC) and MC38 (MSI-H-CRC) syngeneic tumours, while knockin promoted an immunosuppressive TIME facilitating CRC in azoxymethane-dextran sulphate-sodium or models. scRNA-seq identified reduction of myeloid-derived suppressor cells (MDSCs), concomitant with increased cytotoxic T cells in knockout tumours. Integrated MeRIP-seq, RNA-seq and Ribo-seq revealed p65/Rela as a YTHDF1 target. YTHDF1 promoted p65 translation to upregulate CXCL1, which increased MDSC migration via CXCL1-CXCR2 axis. Increased MSDCs in turn antagonised functional CD8 T cells in TIME. Importantly, targeting YTHDF1 by CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) or VNPs-si boosted anti-PD1 efficacy in MSI-H CRC, and overcame anti-PD1 resistance in MSS CRC.
CONCLUSION
YTHDF1 impairs antitumour immunity via an mA-p65-CXCL1/CXCR2 axis to promote CRC and serves as a therapeutic target in immune checkpoint blockade therapy.
Topics: Mice; Animals; CD8-Positive T-Lymphocytes; Colonic Neoplasms; Colorectal Neoplasms; Tumor Microenvironment
PubMed: 36717220
DOI: 10.1136/gutjnl-2022-328845 -
Gut Nov 2023is a probiotic species that can suppress intestinal inflammation by producing metabolites. We aimed to study the role of in colorectal tumourigenesis and immunotherapy.
OBJECTIVE
is a probiotic species that can suppress intestinal inflammation by producing metabolites. We aimed to study the role of in colorectal tumourigenesis and immunotherapy.
DESIGN
abundance was evaluated in stools of patients with colorectal cancer (CRC) (n=444) and healthy controls (n=575). The effects of were studied in or azoxymethane (AOM)-induced CRC mouse models, and in syngeneic mouse xenograft models of CT26 (microsatellite instability (MSI)-low) or MC38 (MSI-high). The change of immune landscape was evaluated by multicolour flow cytometry and immunohistochemistry staining. Metabolites were profiled by metabolomic profiling.
RESULTS
was significantly depleted in stools of patients with CRC compared with healthy controls. administration significantly inhibited tumour formation in mice, which was confirmed in mice with AOM-induced CRC. restored gut barrier function as indicated by improved intestinal permeability and enhanced expression of tight junction proteins. Butyrate was identified as the functional metabolite generated by or butyrate suppressed tumour growth by inducing cytotoxic granzyme B, interferon (IFN)-γ and tumour necrosis factor (TNF)-α CD8 T cells in orthotopic mouse models of MC38 or CT26. or butyrate also significantly improved antiprogrammed cell death protein 1 (anti-PD-1) efficacy in mice bearing MSI-low CT26 tumours. Mechanistically, butyrate directly bound to toll-like receptor 5 (TLR5) receptor on CD8 T cells to induce its activity through activating nuclear factor kappa B (NF-κB) signalling.
CONCLUSION
protects against colorectal tumourigenesis by producing butyrate, which could also improve anti-PD-1 efficacy by inducing functional CD8 T cells. is a potential adjuvant to augment anti-PD-1 efficacy against CRC.
Topics: Humans; Mice; Animals; CD8-Positive T-Lymphocytes; Butyrates; Carcinogenesis; Cell Transformation, Neoplastic; Colorectal Neoplasms
PubMed: 37491158
DOI: 10.1136/gutjnl-2023-330291 -
Gut Nov 2023Gut microbiota is a key player in dictating immunotherapy response. We aimed to explore the immunomodulatory effect of probiotic and its role in improving...
OBJECTIVE
Gut microbiota is a key player in dictating immunotherapy response. We aimed to explore the immunomodulatory effect of probiotic and its role in improving anti-programmed cell death protein 1 (PD1) efficacy against colorectal cancer (CRC).
DESIGN
The effects of in anti-PD1 response were assessed in syngeneic mouse models and azoxymethane/dextran sulfate sodium-induced CRC model. The change of immune landscape was identified by multicolour flow cytometry and validated by immunohistochemistry staining and in vitro functional assays. Liquid chromatography-mass spectrometry was performed to identify the functional metabolites.
RESULTS
significantly improved anti-PD1 efficacy in two syngeneic mouse models with different microsatellite instability (MSI) statuses (MSI-high for MC38, MSI-low for CT26). Such effect was confirmed in CRC tumourigenesis model. synergised with anti-PD1 therapy by reducing Foxp3 CD25 regulatory T cell (Treg) intratumoural infiltration, and enhancing effector function of CD8 T cells. -derived indole-3-carboxylic acid (ICA) was identified as the functional metabolite. Mechanistically, ICA inhibited indoleamine 2,3-dioxygenase (IDO1) expression, therefore suppressing kynurenine (Kyn) production in tumours. ICA also competed with Kyn for binding site on aryl hydrocarbon receptor (AHR) and antagonised Kyn binding on CD4 T cells, thereby inhibiting Treg differentiation in vitro. ICA phenocopied effect and significantly improved anti-PD1 efficacy in vivo, which could be reversed by Kyn supplementation.
CONCLUSION
-derived ICA improved anti-PD1 efficacy in CRC through suppressing CD4+Treg differentiation and enhancing CD8+T cell function by modulating the IDO1/Kyn/AHR axis. is a potential adjuvant to augment anti-PD1 efficacy against CRC.
Topics: Animals; Mice; CD8-Positive T-Lymphocytes; Colorectal Neoplasms; Kynurenine; Receptors, Aryl Hydrocarbon; T-Lymphocytes, Regulatory; Lactobacillus; Programmed Cell Death 1 Receptor; Immune Checkpoint Inhibitors; Bacterial Lysates
PubMed: 37770127
DOI: 10.1136/gutjnl-2023-329543 -
Gastroenterology Feb 2024Dietary fibers are mainly fermented by the gut microbiota, but their roles in colorectal cancer (CRC) are largely unclear. Here, we investigated the associations of...
BACKGROUND & AIMS
Dietary fibers are mainly fermented by the gut microbiota, but their roles in colorectal cancer (CRC) are largely unclear. Here, we investigated the associations of different fibers with colorectal tumorigenesis in mice.
METHODS
Apc mice and C57BL/6 mice with azoxymethane (AOM) injection were used as CRC mouse models. Mice were fed with mixed high-fiber diet (20% soluble fiber and 20% insoluble fiber), high-inulin diet, high-guar gum diet, high-cellulose diet, or diets with different inulin dose. Germ-free mice were used for validation. Fecal microbiota and metabolites were profiled by shotgun metagenomic sequencing and liquid chromatography-mass spectrometry, respectively.
RESULTS
Mixed high-fiber diet promoted colorectal tumorigenesis with increased tumor number and tumor load in AOM-treated and Apc mice. Antibiotics use abolished the pro-tumorigenic effect of mixed high-fiber diet, while transplanting stools from mice fed with mixed high-fiber diet accelerated tumor growth in AOM-treated germ-free mice. We therefore characterized the contribution of soluble and insoluble fiber in CRC separately. Our results revealed that soluble fiber inulin or guar gum, but not insoluble fiber cellulose, promoted colorectal tumorigenesis in AOM-treated and Apc mice. Soluble fiber induced gut dysbiosis with Bacteroides uniformis enrichment and Bifidobacterium pseudolongum depletion, accompanied by increased fecal butyrate and serum bile acids and decreased inosine. We also identified a positive correlation between inulin dosage and colorectal tumorigenesis. Moreover, transplanting stools from mice fed with high-inulin diet increased colonic cell proliferation and oncogene expressions in germ-free mice.
CONCLUSION
High-dose soluble but not insoluble fiber potentiates colorectal tumorigenesis in a dose-dependent manner by dysregulating gut microbiota and metabolites in mice.
Topics: Mice; Animals; Gastrointestinal Microbiome; Inulin; Mice, Inbred C57BL; Carcinogenesis; Dietary Fiber; Cellulose; Azoxymethane; Colorectal Neoplasms
PubMed: 37858797
DOI: 10.1053/j.gastro.2023.10.012 -
EBioMedicine Jul 2023Obesity is a risk factor for colorectal cancer (CRC). The role of gut microbiota in mediating the cancer-promoting effect of obesity is unknown.
BACKGROUND
Obesity is a risk factor for colorectal cancer (CRC). The role of gut microbiota in mediating the cancer-promoting effect of obesity is unknown.
METHODS
Azoxymethane (AOM)-treated, Apc and germ-free mice were gavaged with feces from obese individuals and control subjects respectively. The colonic tumor load and number were recorded at the endpoint in two carcinogenic models. The gut microbiota composition and colonic transcriptome were assessed by metagenomic sequencing and RNA sequencing, respectively. The anticancer effects of bacteria depleted in fecal samples of obese individuals were validated.
FINDINGS
Conventional AOM-treated and Apc mice receiving feces from obese individuals showed significantly increased colon tumor formation compared with those receiving feces from control subjects. AOM-treated mice receiving feces from obese individuals showed impaired intestinal barrier function and significant upregulation of pro-inflammatory cytokines and activation of oncogenic Wnt signaling pathway. Consistently, transferring feces from obese individuals to germ-free mice led to increased colonic cell proliferation, intestinal barrier function impairment, and induction of oncogenic and proinflammatory gene expression. Moreover, germ-free mice transplanted with feces from obese human donors had increased abundance of potential pathobiont Alistipes finegoldii, and reduced abundance of commensals Bacteroides vulgatus and Akkermansia muciniphila compared with those receiving feces from human donors with normal body mass index (BMI). Validation experiments showed that B. vulgatus and A. muciniphila demonstrated anti-proliferative effects in CRC, while A. finegoldii promoted CRC tumor growth.
INTERPRETATION
Our results supported the role of obesity-associated microbiota in colorectal carcinogenesis and identified putative bacterial candidates that may mediate its mechanisms. Microbiota modulation in obese individuals may provide new approaches to prevent or treat obesity-related cancers including CRC.
FUNDING
This work was funded by National Key Research and Development Program of China (2020YFA0509200/2020YFA0509203), National Natural Science Foundation of China (81922082), RGC Theme-based Research Scheme Hong Kong (T21-705/20-N), RGC Research Impact Fund Hong Kong (R4632-21F), RGC-CRF Hong Kong (C4039-19GF and C7065-18GF), RGC-GRF Hong Kong (14110819, 14111621), and NTU Start-Up Grant (021337-00001).
Topics: Humans; Mice; Animals; Gastrointestinal Microbiome; Colonic Neoplasms; Carcinogenesis; Obesity; Azoxymethane; Colorectal Neoplasms; Mice, Inbred C57BL; Disease Models, Animal
PubMed: 37343363
DOI: 10.1016/j.ebiom.2023.104670 -
International Journal of Biological... 2023(), a gram-negative anaerobic bacterium, is selectively decreased in the fecal microbiota of patients with colorectal cancer (CRC), but its molecular mechanism in CRC...
(), a gram-negative anaerobic bacterium, is selectively decreased in the fecal microbiota of patients with colorectal cancer (CRC), but its molecular mechanism in CRC development remains inconclusive. In this study, we first confirmed the inhibitory effect of on CRC formation and analyzed the metabolic role of intestinal flora in human Polyps, A-CRA (advanced colorectal adenoma) and CRC samples. To better clarify the role of in CRC development, a pseudo-germ-free (GF) azoxymethane (AOM)/dextran sulfate sodium (DSS) mouse model was established, followed by infection with or without . Metabolomic analysis and RNA-seq analysis showed tryptophan-mediated aryl hydrocarbon receptor (AhR) was significantly down-regulated in -infected CRC mice. Then, mice with intestinal specific AhR deficiency (AhR Cre) were generated and were used in 2 murine models: AOM/DSS treatment as a model of carcinogen-induced colon cancer and a genetically induced model using mice. Notably, AhR deficiency inhibited CRC growth in the AOM/DSS and mouse model. Moreover, AhR deficiency inhibited, rather than enhanced, tumor formation and tumor-derived organoids in Apc-deficient cells both and by activating Wnt/β-catenin signaling and TCF4/LEF1-dependent transcription. Furthermore, the antitumor effectiveness of was abolished either in a human colon cancer tumor model induced by subcutaneous transplantation of AhR-silenced CRC cells, or AhR-deficienty spontaneous colorectal cancer model. In conclusion, supplementation with . protected mice from CRC development by specifically inhibiting tryptophan-mediated AhR/β-catenin signaling.
Topics: Humans; Mice; Animals; beta Catenin; Tryptophan; Receptors, Aryl Hydrocarbon; Base Composition; Phylogeny; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Colorectal Neoplasms; Colonic Neoplasms; Wnt Signaling Pathway; Mice, Inbred C57BL
PubMed: 37781044
DOI: 10.7150/ijbs.85712 -
EMBO Reports Sep 2023Inflammation plays an important role in the initiation and progression of colorectal cancer (CRC) and leads to β-catenin accumulation in colitis-related CRC. However,...
Inflammation plays an important role in the initiation and progression of colorectal cancer (CRC) and leads to β-catenin accumulation in colitis-related CRC. However, the mechanism remains largely unknown. Here, pancreatic progenitor cell differentiation and proliferation factor (PPDPF) is found to be upregulated in CRC and significantly correlated with tumor-node-metastasis (TNM) stages and survival time. Knockout of PPDPF in the intestinal epithelium shortens crypts, decreases the number of stem cells, and inhibits the growth of organoids and the occurrence of azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced CRC. Mechanistically, PPDPF is found to interact with Casein kinase 1α (CK1α), thereby disrupting its binding to Axin, disassociating the β-catenin destruction complex, decreasing the phosphorylation of β-catenin, and activating the Wnt/β-catenin pathway. Furthermore, interleukin 6 (IL6)/Janus kinase 2 (JAK2)-mediated inflammatory signals lead to phosphorylation of PPDPF at Tyr16 and Tyr17, stabilizing the protein. In summary, this study demonstrates that PPDPF is a key molecule in CRC carcinogenesis and progression that connects inflammatory signals to the Wnt/β-catenin signaling pathway, providing a potential novel therapeutic target.
Topics: Humans; Interleukin-6; Phosphorylation; beta Catenin; Wnt Signaling Pathway; Janus Kinase 2; Colorectal Neoplasms; Cell Proliferation; Cell Line, Tumor; Gene Expression Regulation, Neoplastic
PubMed: 37477088
DOI: 10.15252/embr.202255060 -
Advanced Science (Weinheim,... Sep 2023Men demonstrate higher incidence and mortality rates of colorectal cancer (CRC) than women. This study aims to explain the potential causes of such sexual dimorphism in...
Men demonstrate higher incidence and mortality rates of colorectal cancer (CRC) than women. This study aims to explain the potential causes of such sexual dimorphism in CRC from the perspective of sex-biased gut microbiota and metabolites. The results show that sexual dimorphism in colorectal tumorigenesis is observed in both Apc mice and azoxymethane (AOM)/dextran sulfate sodium (DSS)-treated mice with male mice have significantly larger and more tumors, accompanied by more impaired gut barrier function. Moreover, pseudo-germ mice receiving fecal samples from male mice or patients show more severe intestinal barrier damage and higher level of inflammation. A significant change in gut microbiota composition is found with increased pathogenic bacteria Akkermansia muciniphila and deplets probiotic Parabacteroides goldsteinii in both male mice and pseudo-germ mice receiving fecal sample from male mice. Sex-biased gut metabolites in pseudo-germ mice receiving fecal sample from CRC patients or CRC mice contribute to sex dimorphism in CRC tumorigenesis through glycerophospholipids metabolism pathway. Sexual dimorphism in tumorigenesis of CRC mouse models. In conclusion, the sex-biased gut microbiome and metabolites contribute to sexual dimorphism in CRC. Modulating sex-biased gut microbiota and metabolites could be a potential sex-targeting therapeutic strategy of CRC.
Topics: Male; Female; Animals; Mice; Colorectal Neoplasms; Gastrointestinal Microbiome; Dextran Sulfate; Carcinogenesis; Cell Transformation, Neoplastic
PubMed: 37400423
DOI: 10.1002/advs.202206238 -
Advanced Science (Weinheim,... Aug 2023Transforming growth factor beta (TGF-β), a multifunctional cytokine, plays critical roles in immune responses. However, the precise role of TGF-β in colitis and...
Transforming growth factor beta (TGF-β), a multifunctional cytokine, plays critical roles in immune responses. However, the precise role of TGF-β in colitis and colitis-associated cancer remains poorly defined. Here, it is demonstrated that TGF-β promotes the colonic inflammation and related tumorigenesis in the absence of Smad family member 4 (Smad4). Smad4 loss in intestinal epithelium aggravates colitis and colitis-associated neoplasia induced by dextran sulfate sodium (DSS) and azoxymethane/dextran sulfate sodium (AOM/DSS), leading to over-activated immune responses and increased TGF-β1 levels. In Smad4-deficient organoids, TGF-β1 stimulates spheroid formation and impairs intestinal stem cell proliferation and lineage specification. YAP, whose expression is directly upregulated by TGF-β1 after Smad4 deletion, mediates the effect of TGF-β1 by interacting with Smad2/3. Attenuation of YAP/TAZ prevents TGF-β1-induced spheroid formation in Smad4 organoids and alleviates colitis and colitis-associated cancer in Smad4-deficient mice. Collectively, these results highlight an integral role of the TGF-β/Smad4 axis in restraining intestinal inflammation and tumorigenesis and suggest TGF-β or YAP signaling as therapeutic targets for these gastrointestinal diseases intervention.
Topics: Mice; Animals; Transforming Growth Factor beta; Transforming Growth Factor beta1; Colitis-Associated Neoplasms; Dextran Sulfate; Inflammation; Carcinogenesis; Colitis; Cell Transformation, Neoplastic; Intestinal Mucosa
PubMed: 37261975
DOI: 10.1002/advs.202300708