-
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 Dec 2022Cigarette smoking is a major risk factor for colorectal cancer (CRC). We aimed to investigate whether cigarette smoke promotes CRC by altering the gut microbiota and...
OBJECTIVE
Cigarette smoking is a major risk factor for colorectal cancer (CRC). We aimed to investigate whether cigarette smoke promotes CRC by altering the gut microbiota and related metabolites.
DESIGN
Azoxymethane-treated C57BL/6 mice were exposed to cigarette smoke or clean air 2 hours per day for 28 weeks. Shotgun metagenomic sequencing and liquid chromatography mass spectrometry were parallelly performed on mice stools to investigate alterations in microbiota and metabolites. Germ-free mice were transplanted with stools from smoke-exposed and smoke-free control mice.
RESULTS
Mice exposed to cigarette smoke had significantly increased tumour incidence and cellular proliferation compared with smoke-free control mice. Gut microbial dysbiosis was observed in smoke-exposed mice with significant differential abundance of bacterial species including the enrichment of and depletion of and spp. Metabolomic analysis showed increased bile acid metabolites, especially taurodeoxycholic acid (TDCA) in the colon of smoke-exposed mice. We found that had the most positive correlation with TDCA in smoke-exposed mice. Moreover, smoke-exposed mice manifested enhanced oncogenic MAPK/ERK (mitogen-activated protein kinase/extracellular signal‑regulated protein kinase 1/2) signalling (a downstream target of TDCA) and impaired gut barrier function. Furthermore, germ-free mice transplanted with stools from smoke-exposed mice (GF-AOMS) had increased colonocyte proliferation. Similarly, GF-AOMS showed increased abundances of gut and TDCA, activated MAPK/ERK pathway and impaired gut barrier in colonic epithelium.
CONCLUSION
The gut microbiota dysbiosis induced by cigarette smoke plays a protumourigenic role in CRC. The smoke-induced gut microbiota dysbiosis altered gut metabolites and impaired gut barrier function, which could activate oncogenic MAPK/ERK signalling in colonic epithelium.
Topics: Animals; Mice; Gastrointestinal Microbiome; Dysbiosis; Cigarette Smoking; Mice, Inbred C57BL; Carcinogenesis; Colorectal Neoplasms
PubMed: 35387878
DOI: 10.1136/gutjnl-2021-325021 -
Gastroenterology Jan 2022Dietary fat intake is associated with increased risk of colorectal cancer (CRC). We examined the role of high-fat diet (HFD) in driving CRC through modulating gut...
BACKGROUND AND AIMS
Dietary fat intake is associated with increased risk of colorectal cancer (CRC). We examined the role of high-fat diet (HFD) in driving CRC through modulating gut microbiota and metabolites.
METHODS
HFD or control diet was fed to mice littermates in CRC mouse models of an azoxymethane (AOM) model and Apc model, with or without antibiotics cocktail treatment. Germ-free mice for fecal microbiota transplantation were used for validation. Gut microbiota and metabolites were detected using metagenomic sequencing and high-performance liquid chromatography-mass spectrometry, respectively. Gut barrier function was determined using lipopolysaccharides level and transmission electron microscopy.
RESULTS
HFD promoted colorectal tumorigenesis in both AOM-treated mice and Apc mice compared with control diet-fed mice. Gut microbiota depletion using antibiotics attenuated colon tumor formation in HFD-fed mice. A significant shift of gut microbiota composition with increased pathogenic bacteria Alistipessp.Marseille-P5997 and Alistipessp.5CPEGH6, and depleted probiotic Parabacteroides distasonis, along with impaired gut barrier function was exhibited in HFD-fed mice. Moreover, HFD-modulated gut microbiota promotes colorectal tumorigenesis in AOM-treated germ-free mice, indicating gut microbiota was essential in HFD-associated colorectal tumorigenesis. Gut metabolites alteration, including elevated lysophosphatidic acid, which was confirmed to promote CRC cell proliferation and impair cell junction, was also observed in HFD-fed mice. Moreover, transfer of stools from HFD-fed mice to germ-free mice without interference increased colonic cell proliferation, impaired gut barrier function, and induced oncogenic genes expression.
CONCLUSIONS
HFD drives colorectal tumorigenesis through inducing gut microbial dysbiosis, metabolomic dysregulation with elevated lysophosphatidic acid, and gut barrier dysfunction in mice.
Topics: Animals; Anti-Bacterial Agents; Azoxymethane; Bacteria; Bacterial Translocation; Cell Proliferation; Cell Transformation, Neoplastic; Colon; Colorectal Neoplasms; Diet, High-Fat; Disease Models, Animal; Dysbiosis; Fecal Microbiota Transplantation; Feces; Gastrointestinal Microbiome; Genes, APC; Germ-Free Life; Humans; Lysophospholipids; Male; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Transgenic; Permeability; Tumor Cells, Cultured; Mice
PubMed: 34461052
DOI: 10.1053/j.gastro.2021.08.041 -
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 -
Gastroenterology Mar 2022Because inflammatory bowel disease is increasing worldwide and can lead to colitis-associated carcinoma (CAC), new interventions are needed. We have shown that spermine...
BACKGROUND & AIMS
Because inflammatory bowel disease is increasing worldwide and can lead to colitis-associated carcinoma (CAC), new interventions are needed. We have shown that spermine oxidase (SMOX), which generates spermidine (Spd), regulates colitis. Here we determined whether Spd treatment reduces colitis and carcinogenesis.
METHODS
SMOX was quantified in human colitis and associated dysplasia using quantitative reverse-transcription polymerase chain reaction and immunohistochemistry. We used wild-type (WT) and Smox C57BL/6 mice treated with dextran sulfate sodium (DSS) or azoxymethane (AOM)-DSS as models of colitis and CAC, respectively. Mice with epithelial-specific deletion of Apc were used as a model of sporadic colon cancer. Animals were supplemented or not with Spd in the drinking water. Colonic polyamines, inflammation, tumorigenesis, transcriptomes, and microbiomes were assessed.
RESULTS
SMOX messenger RNA levels were decreased in human ulcerative colitis tissues and inversely correlated with disease activity, and SMOX protein was reduced in colitis-associated dysplasia. DSS colitis and AOM-DSS-induced dysplasia and tumorigenesis were worsened in Smox vs WT mice and improved in both genotypes with Spd. Tumor development caused by Apc deletion was also reduced by Spd. Smox deletion and AOM-DSS treatment were both strongly associated with increased expression of α-defensins, which was reduced by Spd. A shift in the microbiome, with reduced abundance of Prevotella and increased Proteobacteria and Deferribacteres, occurred in Smox mice and was reversed with Spd.
CONCLUSIONS
Loss of SMOX is associated with exacerbated colitis and CAC, increased α-defensin expression, and dysbiosis of the microbiome. Spd supplementation reverses these phenotypes, indicating that it has potential as an adjunctive treatment for colitis and chemopreventive for colon carcinogenesis.
Topics: Adenomatous Polyposis Coli Protein; Animals; Azoxymethane; Carcinogenesis; Colitis; Colitis, Ulcerative; Colon; Colonic Neoplasms; Dextran Sulfate; Gastrointestinal Microbiome; Gene Expression Regulation; Humans; Intestinal Mucosa; Male; Mice; Oxidoreductases Acting on CH-NH Group Donors; Precancerous Conditions; Protective Factors; RNA, Messenger; Severity of Illness Index; Spermidine; Weight Loss; alpha-Defensins; Polyamine Oxidase
PubMed: 34767785
DOI: 10.1053/j.gastro.2021.11.005 -
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 -
Cancer Communications (London, England) Sep 2022Abnormal expression of protein tyrosine phosphatases (PTPs) has been reported to be a crucial cause of cancer. As a member of PTPs, protein tyrosine phosphatase receptor...
BACKGROUND
Abnormal expression of protein tyrosine phosphatases (PTPs) has been reported to be a crucial cause of cancer. As a member of PTPs, protein tyrosine phosphatase receptor type O (PTPRO) has been revealed to play tumor suppressive roles in several cancers, while its roles in colorectal cancer (CRC) remains to be elucidated. Hence, we aimed to explore the roles and mechanisms of PTPRO in CRC initiation and progression.
METHODS
The influences of PTPRO on the growth and liver metastasis of CRC cells and the expression patterns of different lipid metabolism enzymes were evaluated in vitro and in vivo. Molecular and biological experiments were conducted to uncover the underpinning mechanisms of dysregulated de novo lipogenesis and fatty acid β-oxidation.
RESULTS
PTPRO expression was notably downregulated in CRC liver metastasis compared to the primary cancer, and such a downregulation was associated with poor prognosis of patients with CRC. PTPRO silencing significantly promoted cell growth and liver metastasis. Compared with PTPRO wild-type mice, PTPRO-knockout mice developed more tumors and harbored larger tumor loads under treatment with azoxymethane and dextran sulfate sodium. Gene set enrichment analysis revealed that PTPRO downregulation was significantly associated with the fatty acid metabolism pathways. Blockage of fatty acid synthesis abrogated the effects of PTPRO silencing on cell growth and liver metastasis. Further experiments indicated that PTPRO silencing induced the activation of the AKT serine/threonine kinase (AKT)/mammalian target of rapamycin (mTOR) signaling axis, thus promoting de novo lipogenesis by enhancing the expression of sterol regulatory element-binding protein 1 (SREBP1) and its target lipogenic enzyme acetyl-CoA carboxylase alpha (ACC1) by activating the AKT/mTOR signaling pathway. Furthermore, PTPRO attenuation decreased the fatty acid oxidation rate by repressing the expression of peroxisome proliferator-activated receptor alpha (PPARα) and its downstream enzyme peroxisomal acyl-coenzyme A oxidase 1 (ACOX1) via activating the p38/extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase (MAPK) signaling pathway.
CONCLUSIONS
PTPRO could suppress CRC development and metastasis via modulating the AKT/mTOR/SREBP1/ACC1 and MAPK/PPARα/ACOX1 pathways and reprogramming lipid metabolism.
Topics: Animals; Carcinogenesis; Carrier Proteins; Colorectal Neoplasms; Fatty Acids; Lipid Metabolism; Liver Neoplasms; Mammals; Mice; PPAR alpha; Proto-Oncogene Proteins c-akt; Receptor-Like Protein Tyrosine Phosphatases, Class 3; TOR Serine-Threonine Kinases
PubMed: 35904817
DOI: 10.1002/cac2.12341 -
Theranostics 2022Tumor-associated macrophages (TAMs), generally displaying the pro-tumor M2-like phenotype, strongly influence the progression of colorectal cancer (CRC) via their...
Tumor-associated macrophages (TAMs), generally displaying the pro-tumor M2-like phenotype, strongly influence the progression of colorectal cancer (CRC) via their immunosuppressive activities. The high-mobility gene group A2 (HMGA2), an oncoprotein, is aberrantly overexpressed in CRC cells. However, the mechanisms by which tumor-derived HMGA2 modulates tumor microenvironment in CRC remain poorly understood. subcutaneous tumor xenograft model, azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced tumor mouse model and co-culture assays were used to investigate the Hmga2 role in TAM recruitment and polarization. Luciferase and chromatin immunoprecipitation (ChIP) assays were applied to examine the mechanism of HMGA2-mediated transcriptional regulation of signal transducer and activator of transcription 3 (STAT3). The CD68 correlation with patient outcome was analyzed in 167 human CRC tissues. We found that HMGA2 in cancer cells promoted macrophage recruitment and M2 polarization and . HMGA2 directly bound to the promoter to activate its transcription and subsequently induced CCL2 secretion, thus promoting macrophage recruitment. Our results from human CRC specimens also revealed a strong positive association between HMGA2 expression in tumor cells and CD68 expression in the stroma. We further showed that patients with an elevated CD68 expression had an unfavorable overall survival in all of the patients or in the subgroup with negative distant metastasis. Our work uncovers new insight into the link between the HMGA2/STAT3/CCL2 axis and macrophage recruitment in CRC. These findings provide a novel therapeutic option for targeting the HMGA2/STAT3/CCL2 axis in CRC.
Topics: Animals; Cell Polarity; Chemokine CCL2; Colorectal Neoplasms; Disease Progression; Gene Expression Regulation, Neoplastic; Gene Knockout Techniques; HEK293 Cells; HMGA2 Protein; Humans; Intestinal Mucosa; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Promoter Regions, Genetic; STAT3 Transcription Factor; Tumor-Associated Macrophages
PubMed: 34976223
DOI: 10.7150/thno.65411 -
Gastroenterology Apr 2023Colorectal cancer is a leading cause of cancer death, and a major risk factor is chronic inflammation. Despite the link between colitis and cancer, the mechanism by...
BACKGROUND & AIMS
Colorectal cancer is a leading cause of cancer death, and a major risk factor is chronic inflammation. Despite the link between colitis and cancer, the mechanism by which inflammation leads to colorectal cancer is not well understood.
METHODS
To investigate whether different forms of inflammation pose the same risk of cancer, we compared several murine models of colitis (dextran sodium sulfate [DSS], 2,4,6-trinitrobenzene sulfonic acid, 4-ethoxylmethylene-2-phenyloxazol-5-one, Citrobacter rodentium, Fusobacterium nucleatum, and doxorubicin) with respect to their ability to lead to colonic tumorigenesis. We attempted to correlate the severity of colitis and inflammatory profile with the risk of tumorigenesis in both azoxymethane-dependent and Dclk1/APC murine models of colitis-associated cancer.
RESULTS
DSS colitis reproducibly led to colonic tumors in both mouse models of colitis-associated cancer. In contrast, all other forms of colitis did not lead to cancer. When compared with the colitis not associated with tumorigenesis, DSS colitis was characterized by significantly increased CD11bF4/80Ly6C macrophages and CD11bLy6G neutrophils. Interestingly, depletion of the CD11bF4/80Ly6C macrophages inhibited tumorigenesis, whereas depletion of CD11bLy6G neutrophils had no effect on tumorigenesis. Furthermore, the macrophage-derived cytokines interleukin-1β, tumor necrosis factor-α, and interleukin-6 were significantly increased in DSS colitis and promoted stemness of Dclk1 tuft cells that serve as the cellular origin of cancer.
CONCLUSIONS
We have identified CD11bF4/80Ly6C macrophages as key mediators of cancer initiation in colitis-associated cancer. Development of new therapies that target these cells may provide an effective preventative strategy for colitis-associated cancer.
Topics: Animals; Mice; Azoxymethane; Carcinogenesis; Cell Plasticity; Colitis; Colitis-Associated Neoplasms; Dextran Sulfate; Disease Models, Animal; Inflammation; Macrophages; Mice, Inbred C57BL
PubMed: 36634827
DOI: 10.1053/j.gastro.2023.01.002