Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 20 de 464
1.
Cardiovasc Res ; 120(6): 612-622, 2024 May 07.
Article En | MEDLINE | ID: mdl-38400709

AIMS: Heart failure (HF) and cancer are the leading causes of death worldwide. Epidemiological studies revealed that HF patients are prone to develop cancer. Preclinical studies provided some insights into this connection, but the exact mechanisms remain elusive. In colorectal cancer (CRC), gut microbial dysbiosis is linked to cancer progression and recent studies have shown that HF patients display microbial dysbiosis. This current study focussed on the effects of HF-induced microbial dysbiosis on colonic tumour formation. METHODS AND RESULTS: C57BL/6J mice were subjected to myocardial infarction (MI), with sham surgery as control. After six weeks faeces were collected, processed for 16 s rRNA sequencing, and pooled for faecal microbiota transplantation. CRC tumour growth was provoked in germ-free mice by treating them with Azoxymethane/Dextran sodium sulphate. The CRC mice were transplanted with faeces from MI or sham mice. MI-induced HF resulted in microbial dysbiosis, characterized by a decreased α-diversity and microbial alterations on the genus level, several of which have been associated with CRC. We then performed faecal microbiota transplantation with faeces from HF mice in CRC mice, which resulted in a higher endoscopic disease score and an increase in the number of tumours in CRC mice. CONCLUSION: We demonstrated that MI-induced HF contributes to colonic tumour formation by altering the gut microbiota composition, providing a mechanistic explanation for the observed association between HF and increased risk for cancer. Targeting the microbiome may present as a tool to mitigate HF-associated co-morbidities, especially cancer.


Colon , Disease Models, Animal , Dysbiosis , Fecal Microbiota Transplantation , Gastrointestinal Microbiome , Heart Failure , Mice, Inbred C57BL , Myocardial Infarction , Animals , Myocardial Infarction/pathology , Myocardial Infarction/microbiology , Heart Failure/microbiology , Heart Failure/pathology , Heart Failure/etiology , Male , Colon/microbiology , Colon/pathology , Ribotyping , Colonic Neoplasms/pathology , Colonic Neoplasms/microbiology , Bacteria/genetics , Feces/microbiology , Host-Pathogen Interactions
2.
World J Microbiol Biotechnol ; 39(12): 333, 2023 Oct 06.
Article En | MEDLINE | ID: mdl-37801157

pks+ Escherichia coli (E. coli) triggers genomic instability in normal colon cells which leads to colorectal cancer (CRC) tumorigenesis. Previously, we reported a significant presentation of pks+ E. coli strains in CRC patients' biopsies as compared to healthy cohorts. In this work, using an in vitro infection model, we further explored the ability of these strains in modulating cell cycle arrest and activation of apoptotic mediators in both primary colon epithelial cells (PCE) and CRC cells (HCT-116). Sixteen strains, of which eight tumours and the matching non-malignant tissues, respectively, from eight pks+ E. coli CRC patients were subjected to BrDU staining and cell cycle analysis via flow cytometry, while a subset of these strains underwent analysis of apoptotic mediators including caspase proteins, cellular reactive oxygen species (cROS) and mitochondrial membrane potential (MMP) via spectrophotometry as well as proinflammatory cytokines via flow cytometry. Data revealed that all strains exerted S-phase cell cycle blockade in both cells and G2/M phase in PCE cells only. Moreover, more significant upregulation of Caspase 9, cROS, proinflammatory cytokines and prominent downregulation of MMP were detected in HCT-116 cells indicating the potential role of pks related bacterial toxin as anticancer agent as compared to PCE cells which undergo cellular senescence leading to cell death without apparent upregulation of apoptotic mediators. These findings suggest the existence of discrepancies underlying the mechanism of action of pks+ E. coli on both cancer and normal cell lines. This work propounds the rationale to further understand the mechanism underlying pks+ E. coli-mediated CRC tumorigenesis and cancer killing.


Colonic Neoplasms , Escherichia coli , Humans , Escherichia coli/genetics , Colonic Neoplasms/microbiology , Colonic Neoplasms/pathology , Cell Cycle Checkpoints , Cell Line , Apoptosis , Carcinogenesis , Cytokines , Cell Line, Tumor , Cell Cycle
3.
Cell Host Microbe ; 31(3): 418-432.e8, 2023 03 08.
Article En | MEDLINE | ID: mdl-36893736

The intestinal microbiota plays an important role in colorectal cancer (CRC) progression. However, the effect of tissue-resident commensal bacteria on CRC immune surveillance remains poorly understood. Here, we analyzed the intratissue bacteria from CRC patient colon tissues. We found that the commensal bacteria belonging to the Lachnospiraceae family, including Ruminococcus gnavus (Rg), Blautia producta (Bp), and Dorea formicigenerans (Df), were enriched in normal tissues, while Fusobacterium nucleatum (Fn) and Peptostreptococcus anaerobius (Pa) were abundant in tumor tissues. Tissue-resident Rg and Bp reduced colon tumor growth and promoted the activation of CD8+ T cells in immunocompetent mice. Mechanistically, intratissue Rg and Bp degraded lyso-glycerophospholipids that inhibited CD8+ T cell activity and maintained the immune surveillance function of CD8+ T cells. Lyso-glycerophospholipids alone promoted tumor growth that was abrogated with Rg and Bp injection. Collectively, intratissue Lachnospiraceae family bacteria facilitate the immune surveillance function of CD8+ T cells and control colorectal cancer progression.


Colonic Neoplasms , Colorectal Neoplasms , Animals , Mice , Colorectal Neoplasms/microbiology , CD8-Positive T-Lymphocytes , Carcinogenesis , Colonic Neoplasms/microbiology , Fusobacterium nucleatum
4.
Microbiol Spectr ; 10(3): e0105522, 2022 06 29.
Article En | MEDLINE | ID: mdl-35587635

Enterotoxigenic Bacteroides fragilis (ETBF) is consistently found at higher frequency in individuals with sporadic and hereditary colorectal cancer (CRC) and induces tumorigenesis in several mouse models of CRC. However, whether specific mutations induced by ETBF lead to colon tumor formation has not been investigated. To determine if ETBF-induced mutations impact the Apc gene, and other tumor suppressors or proto-oncogenes, we performed whole-exome sequencing and whole-genome sequencing on tumors isolated after ETBF and sham colonization of Apcmin/+ and Apcmin/+Msh2fl/flVC mice, as well as whole-genome sequencing of organoids cocultured with ETBF. Our results indicate that ETBF-induced tumor formation results from loss of heterozygosity (LOH) of Apc, unless the mismatch repair system is disrupted, in which case, tumor formation results from new acquisition of protein-truncating mutations in Apc. In contrast to polyketide synthase-positive Escherichia coli (pks+ E. coli), ETBF does not produce a unique mutational signature; instead, ETBF-induced tumors arise from errors in DNA mismatch repair and homologous recombination DNA damage repair, established pathways of tumor formation in the colon, and the same genetic mechanism accounting for sham tumors in these mouse models. Our analysis informs how this procarcinogenic bacterium may promote tumor formation in individuals with inherited predispositions to CRC, such as Lynch syndrome or familial adenomatous polyposis (FAP). IMPORTANCE Many studies have shown that microbiome composition in both the mucosa and the stool differs in individuals with sporadic and hereditary colorectal cancer (CRC). Both human and mouse models have established a strong association between particular microbes and colon tumor induction. However, the genetic mechanisms underlying putative microbe-induced colon tumor formation are not well established. In this paper, we applied whole-exome sequencing and whole-genome sequencing to investigate the impact of ETBF-induced genetic changes on tumor formation. Additionally, we performed whole-genome sequencing of human colon organoids exposed to ETBF to validate the mutational patterns seen in our mouse models and begin to understand their relevance in human colon epithelial cells. The results of this study highlight the importance of ETBF colonization in the development of sporadic CRC and in individuals with hereditary tumor conditions, such as Lynch syndrome and familial adenomatous polyposis (FAP).


Adenomatous Polyposis Coli , Bacterial Infections , Colonic Neoplasms , Colorectal Neoplasms, Hereditary Nonpolyposis , Colorectal Neoplasms , Adenomatous Polyposis Coli/genetics , Adenomatous Polyposis Coli/pathology , Animals , Bacterial Infections/pathology , Bacteroides fragilis/genetics , Bacteroides fragilis/metabolism , Colon/microbiology , Colonic Neoplasms/genetics , Colonic Neoplasms/microbiology , Colonic Neoplasms/pathology , Colorectal Neoplasms/microbiology , Colorectal Neoplasms, Hereditary Nonpolyposis/genetics , Colorectal Neoplasms, Hereditary Nonpolyposis/pathology , Disease Models, Animal , Escherichia coli/genetics , Genes, APC , Mice , Mutation
5.
Sci Rep ; 12(1): 1432, 2022 01 26.
Article En | MEDLINE | ID: mdl-35082322

Faecal (FM) and colon mucosal associated microbiota (MAM) were studied in a model of colorectal cancer (CRC), the Apc-mutated Pirc rats, and in age-paired wt F344 rats. Principal Coordinates Analysis indicated that samples' distribution was driven by age, with samples of young rats (1 month old; without tumours) separated from older ones (11-month-old; bearing tumours). Diversity analysis showed significant differences between FM and MAM in older Pirc rats, and between MAM of both Pirc and wt rats and the tumour microbiota, enriched in Enterococcus, Escherichia/Shigella, Proteus and Bifidobacteriaceae. In young animals, Pirc FM was enriched in the genus Delftia, while wt FM was enriched in Lactobacillus and Streptococcus. Some CRC biomarkers and faecal short chain fatty acids (SCFAs) were also measured. Colon proliferation and DClK1 expression, a pro-survival mucosal marker, were higher in Pirc than in wt rats, while the mucin MUC2, was lower in Pirc rats. Branched SCFAs were higher in Pirc than in wt animals. By Spearman analysis CRC biomarkers correlated with FM (in both young and old rats) and with MAM (in young rats), suggesting a specific relationship between the gut microbiota profile and these functional mucosal parameters deserving further investigation.


Biomarkers, Tumor/genetics , Carcinogenesis/genetics , Colon/microbiology , Colonic Neoplasms/genetics , Doublecortin-Like Kinases/genetics , Mucin-2/genetics , Age Factors , Animals , Bifidobacterium/growth & development , Bifidobacterium/isolation & purification , Biomarkers, Tumor/metabolism , Carcinogenesis/metabolism , Carcinogenesis/pathology , Colon/metabolism , Colonic Neoplasms/metabolism , Colonic Neoplasms/microbiology , Colonic Neoplasms/pathology , Disease Models, Animal , Doublecortin-Like Kinases/metabolism , Enterococcus/growth & development , Enterococcus/isolation & purification , Escherichia/growth & development , Escherichia/isolation & purification , Fatty Acids, Volatile/metabolism , Feces/microbiology , Gene Expression Regulation , Lactobacillus/growth & development , Lactobacillus/isolation & purification , Male , Mucin-2/metabolism , Principal Component Analysis , Proteus/growth & development , Proteus/isolation & purification , Rats , Rats, Inbred F344 , Shigella/growth & development , Shigella/isolation & purification , Streptococcus/growth & development , Streptococcus/isolation & purification
6.
Gut ; 71(3): 457-466, 2022 03.
Article En | MEDLINE | ID: mdl-34253574

OBJECTIVE: In this study, we determined whether Helicobacter pylori (H. pylori) infection dampens the efficacy of cancer immunotherapies. DESIGN: Using mouse models, we evaluated whether immune checkpoint inhibitors or vaccine-based immunotherapies are effective in reducing tumour volumes of H. pylori-infected mice. In humans, we evaluated the correlation between H. pylori seropositivity and the efficacy of the programmed cell death protein 1 (PD-1) blockade therapy in patients with non-small-cell lung cancer (NSCLC). RESULTS: In mice engrafted with MC38 colon adenocarcinoma or B16-OVA melanoma cells, the tumour volumes of non-infected mice undergoing anticytotoxic T-lymphocyte-associated protein 4 and/or programmed death ligand 1 or anti-cancer vaccine treatments were significantly smaller than those of infected mice. We observed a decreased number and activation status of tumour-specific CD8+ T cells in the tumours of infected mice treated with cancer immunotherapies independent of the gut microbiome composition. Additionally, by performing an in vitro co-culture assay, we observed that dendritic cells of infected mice promote lower tumour-specific CD8+ T cell proliferation. We performed retrospective human clinical studies in two independent cohorts. In the Dijon cohort, H. pylori seropositivity was found to be associated with a decreased NSCLC patient survival on anti-PD-1 therapy. The survival median for H. pylori seropositive patients was 6.7 months compared with 15.4 months for seronegative patients (p=0.001). Additionally, in the Montreal cohort, H. pylori seropositivity was found to be associated with an apparent decrease of NSCLC patient progression-free survival on anti-PD-1 therapy. CONCLUSION: Our study unveils for the first time that the stomach microbiota affects the response to cancer immunotherapies and that H. pylori serology would be a powerful tool to personalize cancer immunotherapy treatment.


Adenocarcinoma/drug therapy , Carcinoma, Non-Small-Cell Lung/drug therapy , Colonic Neoplasms/drug therapy , Helicobacter Infections/complications , Immune Checkpoint Inhibitors/therapeutic use , Lung Neoplasms/drug therapy , Adenocarcinoma/microbiology , Adenocarcinoma/pathology , Animals , Cancer Vaccines/therapeutic use , Carcinoma, Non-Small-Cell Lung/microbiology , Carcinoma, Non-Small-Cell Lung/pathology , Colonic Neoplasms/microbiology , Colonic Neoplasms/pathology , Disease Models, Animal , Female , Helicobacter pylori , Humans , Lung Neoplasms/microbiology , Lung Neoplasms/pathology , Male , Mice , Mice, Inbred C57BL , Retrospective Studies
7.
Cell Rep ; 37(6): 109989, 2021 11 09.
Article En | MEDLINE | ID: mdl-34758302

Mutations in mitochondrial genes impairing energy production cause mitochondrial diseases (MDs), and clinical studies have shown that MD patients are prone to bacterial infections. However, the relationship between mitochondrial (dys)function and infection remains largely unexplored, especially in epithelial cells, the first barrier to many pathogens. Here, we generate an epithelial cell model for one of the most common mitochondrial diseases, Leigh syndrome, by deleting surfeit locus protein 1 (SURF1), an assembly factor for respiratory chain complex IV. We use this genetic model and a complementary, nutrient-based approach to modulate mitochondrial respiration rates and show that impaired mitochondrial respiration favors entry of the human pathogen Listeria monocytogenes, a well-established bacterial infection model. Reversely, enhanced mitochondrial energy metabolism decreases infection efficiency. We further demonstrate that endocytic recycling is reduced in mitochondrial respiration-dependent cells, dampening L. monocytogenes infection by slowing the recycling of its host cell receptor c-Met, highlighting a previously undescribed role of mitochondrial respiration during infection.


Colonic Neoplasms/microbiology , Listeria monocytogenes/physiology , Listeriosis/prevention & control , Membrane Proteins/metabolism , Mitochondria/physiology , Mitochondrial Proteins/metabolism , Proto-Oncogene Proteins c-met/metabolism , Respiration , Colonic Neoplasms/metabolism , Colonic Neoplasms/pathology , Energy Metabolism , HCT116 Cells , Humans , Listeriosis/microbiology , Membrane Proteins/genetics , Mitochondrial Proteins/genetics , Proto-Oncogene Proteins c-met/genetics
8.
Sci Rep ; 11(1): 20263, 2021 10 12.
Article En | MEDLINE | ID: mdl-34642332

Recent evidence suggests that Fusobacterium nucleatum (Fn) is associated with the development and progression of colorectal cancer. We aimed to delineate the clinical implications of Fn in metastatic colon cancer. We performed quantitative polymerase chain reaction (qPCR) using DNA samples from synchronous metastatic colon cancer patients with either formalin-fixed paraffin-embedded (FFPE) archival primary site tumor samples or fresh colon tissues. Progression-free survival (PFS)1 and PFS2 were defined as PFS of first- and second-line palliative settings. qPCR for Fn was successfully performed using 112 samples (FFPE, n = 61; fresh tissue, n = 51). Forty-one and 68 patients had right-sided and left-sided colon cancer, respectively. Patients with Fn enriched right-sided colon cancers had shorter PFS1 (9.7 vs. 11.2 months) than the other subgroups (HR 3.54, 95% confidence interval [CI] 1.05-11.99; P = 0.04). Fn positive right-sided colon was also associated with shorter PFS2 (3.7 vs. 6.7 months; HR 2.34, 95% CI 0.69-7.91; P = 0.04). In the univariate analysis, PFS1 was affected by differentiation and Fn positive right-sided colon cancer. The multivariate analysis showed that differentiation (HR 2.68, 95% CI 1.40-5.14, P = 0.01) and Fn positive right-sided colon (HR 0.40, 95% CI 0.18-0.88, P = 0.02) were associated with PFS1. Fn enrichment in right sided colon was not associated with overall survival (OS). Fn enrichment has significantly worse prognosis in terms of PFS1 and PFS2 in patients with right-sided metastatic colon cancers.


Colonic Neoplasms/microbiology , DNA, Bacterial/genetics , Fusobacterium Infections/diagnosis , Fusobacterium nucleatum/isolation & purification , Neoplasms, Multiple Primary/microbiology , Colonic Neoplasms/pathology , DNA, Ribosomal/genetics , Female , Fusobacterium nucleatum/genetics , Humans , Kaplan-Meier Estimate , Male , Neoplasm Metastasis , Prognosis , Progression-Free Survival , RNA, Ribosomal, 16S/genetics
10.
Bioengineered ; 12(1): 7046-7060, 2021 12.
Article En | MEDLINE | ID: mdl-34551683

The microbial diversity and communities in the excrement of healthy and patients suffered from cancer were identified by 16SrDNA sequencing performed on the Illumina Hi Seq sequencing platform. The microbial difference was also analyzed. The sequencing results showed high quality of the data, and the microbial communities were more various in the excrement of cancer patients. And the abundance of Firmicutes phylum was significantly reduced in cancer group. The phylum of Fermicutes, Bacteroidetes in cancer group are significantly down-regulated and up-regulated compared with normal group. The species of Faecalibacterium prausnitzii, Bateroides vulgatus and Fusicatenibacter saccharivorans are significantly lower in cancer group than that in normal group (P< 0.05). The species of Prevetella copri, M. uniformis, and Escherichia coli are significantly higher in the cancer group than that in normal group. The comparative results indicated that beneficial bacterium significantly decreased in colorectal cancer (CRC) group, and harmful bacterium significantly increased in the colon cancer group, meanwhile the acidity, sugar increased whereas the oxygen content decreased to facilitate the growth of harmful bacterium. The results would provide microbial approaches for the treatment of colon cancer by the intake of beneficial microbial communities.


Bacteria , Colonic Neoplasms/microbiology , Gastrointestinal Microbiome/genetics , Bacteria/classification , Bacteria/genetics , Bacteria/pathogenicity , DNA, Bacterial/genetics , Feces/microbiology , Humans , Sequence Analysis, DNA
11.
Int J Biol Sci ; 17(11): 2756-2769, 2021.
Article En | MEDLINE | ID: mdl-34345205

Due to chemotherapeutic drug resistance, tumor recurrence is common in patients with colorectal cancer (CRC) and chemo-resistant patients are often accompanied by defects in the mismatch repair system (MMR). Our previous study has shown that Candida tropicalis (C. tropicalis) is closely related to the occurrence and development of colorectal cancer, but whether this conditional pathogenic fungus is involved in chemotherapy needs further investigation. Here we found that C. tropicalis promoted chemotherapy resistance of colon cancer to oxaliplatin. Compared with oxaliplatin-treated group, the expression of functional MMR proteins in tumors were decreased in C.tropicalis/oxaliplatin -treated group, while the glycolysis level of tumors was up-regulated and the production of lactate was significantly increased in C.tropicalis/oxaliplatin -treated group. Inhibiting lactate production significantly alleviated the chemoresistance and rescued the decreased expression of MMR caused by C. tropicalis. Furthermore, we found that lactate down-regulated the expression of MLH1 through the GPR81-cAMP-PKA-CREB axis. This study clarified that C. tropicalis promoted chemoresistance of colon cancer via producing lactate and inhibiting the expression of MLH1, which may provide novel ideas for improving CRC chemotherapy effect.


Candida tropicalis/metabolism , Colonic Neoplasms/genetics , DNA Mismatch Repair/drug effects , Drug Resistance, Neoplasm/drug effects , Lactic Acid/pharmacology , Animals , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Colonic Neoplasms/drug therapy , Colonic Neoplasms/microbiology , Colonic Neoplasms/pathology , Drug Resistance, Neoplasm/genetics , Glucose/metabolism , Glucose/pharmacology , Glycolysis , Humans , Lactic Acid/metabolism , Male , Mice , Mice, Inbred BALB C , Mice, Nude , MutL Protein Homolog 1/metabolism , Oxaliplatin/pharmacology , Xenograft Model Antitumor Assays
12.
Cell ; 184(19): 5015-5030.e16, 2021 09 16.
Article En | MEDLINE | ID: mdl-34407392

Group 3 innate lymphoid cells (ILC3s) regulate immunity and inflammation, yet their role in cancer remains elusive. Here, we identify that colorectal cancer (CRC) manifests with altered ILC3s that are characterized by reduced frequencies, increased plasticity, and an imbalance with T cells. We evaluated the consequences of these changes in mice and determined that a dialog between ILC3s and T cells via major histocompatibility complex class II (MHCII) is necessary to support colonization with microbiota that subsequently induce type-1 immunity in the intestine and tumor microenvironment. As a result, mice lacking ILC3-specific MHCII develop invasive CRC and resistance to anti-PD-1 immunotherapy. Finally, humans with dysregulated intestinal ILC3s harbor microbiota that fail to induce type-1 immunity and immunotherapy responsiveness when transferred to mice. Collectively, these data define a protective role for ILC3s in cancer and indicate that their inherent disruption in CRC drives dysfunctional adaptive immunity, tumor progression, and immunotherapy resistance.


Colonic Neoplasms/immunology , Colonic Neoplasms/therapy , Disease Progression , Immunity, Innate , Immunotherapy , Lymphocytes/immunology , Animals , Cell Communication/drug effects , Cell Plasticity/drug effects , Colonic Neoplasms/microbiology , Feces/microbiology , Histocompatibility Antigens Class II/metabolism , Humans , Immune Checkpoint Inhibitors/pharmacology , Immunity, Innate/drug effects , Inflammation/immunology , Inflammation/pathology , Inflammatory Bowel Diseases/immunology , Inflammatory Bowel Diseases/microbiology , Inflammatory Bowel Diseases/pathology , Intestines/pathology , Lymphocytes/drug effects , Mice, Inbred C57BL , Microbiota/drug effects , Neoplasm Invasiveness , T-Lymphocytes/drug effects , T-Lymphocytes/immunology , Tissue Donors
13.
Methods Mol Biol ; 2323: 267-280, 2021.
Article En | MEDLINE | ID: mdl-34086287

Spontaneous tumor regression following bacterial infection has been observed for hundreds of years. These observations along with anecdotal medical findings in 1890s led to the development of Coley's "toxins," consisting of killed Streptococcus pyogenes and Serratia marcescens bacteria, as the first cancer immunotherapy. The use of this approach, however, was not widely accepted at the time especially after the introduction of radiation therapy as a treatment for cancer in the early 1900s. Over the last 30-40 years there has been renewed interest in the use of bacteria to treat human solid tumors. This is based on the observation that various nonpathogenic anaerobic bacteria can infiltrate and replicate within solid tumors when given intravenously. Bacteria tested as potential anticancer agents include the Gram-positive obligate anaerobes Bifidobacterium and Clostridium, as well as the gram-negative facultative anaerobe Salmonella. Recent advances in synthetic biology and clinical success in cancer immunotherapy provide renewed momentum for developing bacteria-based cancer immunotherapy for cancer treatment and should allow greater potential for the development of novel therapeutic approaches for this devastating disease.


Biological Therapy/methods , Neoplasms/therapy , RNA Interference , Synthetic Biology/methods , Animals , Cell Line, Tumor , Clinical Trials, Phase I as Topic , Colonic Neoplasms/microbiology , Colonic Neoplasms/therapy , Escherichia coli/genetics , Escherichia coli/physiology , Female , Genetic Vectors/genetics , Genetic Vectors/therapeutic use , Humans , Immunotherapy/methods , Immunotherapy/trends , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Nude , Neoplasms/microbiology , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , RNA, Small Interfering/genetics , RNA, Small Interfering/therapeutic use , Real-Time Polymerase Chain Reaction/methods , Remission Induction , Salmonella typhimurium/genetics , Salmonella typhimurium/physiology , Species Specificity , Specific Pathogen-Free Organisms , Synthetic Biology/trends , Xenograft Model Antitumor Assays
14.
Food Chem Toxicol ; 154: 112287, 2021 Aug.
Article En | MEDLINE | ID: mdl-34058233

Since dietary factors are thought to be responsible for high colon cancer risk, we investigated the chemopreventive effect of jabuticaba seed extract (LJE) by administering yogurt with or without LJE against 1,2 dimethyl hydrazine (DMH)-induced colon carcinogenesis in rats. Results showed that LJE contained a total phenolic content of 57.16 g/100 g of seed extract in which 7.67 and 10.09 g/100 g represented total flavonoids and ellagitannins, respectively. LJE protected DNA and human LDL against induced in vitro oxidation, which was associated with the ellagitannin content and with the free-radical scavenging and reducing capacities. LJE alone had a non-clastogenicity/aneugenicity property, but in combination with cisplatin, it enhanced the chromosome aberrations in cancer cells. In colon cancer-induced rats, yogurt with or without LJE caused a reduction in pro-inflammatory parameters, decreased the RNA expression of antiapoptotic cytokines and increased the expression of proapoptotic cytokines. Moreover, LJE attenuated colon cancer initiation and progression by decreasing aberrant crypt foci and LJE recovered the gut microbiome. Together, this evidence suggests that LJE provides chemopreventive protection against colon cancer development by reducing inflammation and increasing proapoptotic pathways.


1,2-Dimethylhydrazine/toxicity , Carcinogens/toxicity , Colonic Neoplasms/pathology , Gastrointestinal Microbiome/drug effects , Hydrolyzable Tannins/isolation & purification , Hydrolyzable Tannins/pharmacology , Inflammation/prevention & control , Myrtaceae/embryology , Oxidative Stress/drug effects , Plant Extracts/pharmacology , Seeds/chemistry , Animals , Chromosome Aberrations , Colonic Neoplasms/chemically induced , Colonic Neoplasms/metabolism , Colonic Neoplasms/microbiology , Male , Mutagenicity Tests , Precancerous Conditions/chemically induced , Precancerous Conditions/pathology , Rats , Rats, Wistar
15.
Nutrients ; 13(4)2021 Apr 03.
Article En | MEDLINE | ID: mdl-33916690

Tryptophan metabolism, via the kynurenine (Kyn) pathway, and microbial transformation of tryptophan to indolic compounds are fundamental for host health; both of which are altered in colon carcinogenesis. Alterations in tryptophan metabolism begin early in colon carcinogenesis as an adaptive mechanism for the tumor to escape immune surveillance and metastasize. The microbial community is a key part of the tumor microenvironment and influences cancer initiation, promotion and treatment response. A growing awareness of the impact of the microbiome on tryptophan (Trp) metabolism in the context of carcinogenesis has prompted this review. We first compare the different metabolic pathways of Trp under normal cellular physiology to colon carcinogenesis, in both the host cells and the microbiome. Second, we review how the microbiome, specifically indoles, influence host tryptophan pathways under normal and oncogenic metabolism. We conclude by proposing several dietary, microbial and drug therapeutic modalities that can be utilized in combination to abrogate tumorigenesis.


Carcinogenesis/metabolism , Colonic Neoplasms/therapy , Gastrointestinal Microbiome/drug effects , Tryptophan/metabolism , Tumor Escape/drug effects , Basic Helix-Loop-Helix Transcription Factors/antagonists & inhibitors , Basic Helix-Loop-Helix Transcription Factors/metabolism , Carcinogenesis/drug effects , Carcinogenesis/immunology , Colon/microbiology , Colon/pathology , Colonic Neoplasms/immunology , Colonic Neoplasms/metabolism , Colonic Neoplasms/microbiology , Combined Modality Therapy/methods , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/therapeutic use , Gastrointestinal Microbiome/immunology , Host Microbial Interactions/immunology , Humans , Indoleamine-Pyrrole 2,3,-Dioxygenase/antagonists & inhibitors , Indoleamine-Pyrrole 2,3,-Dioxygenase/metabolism , Indoles/administration & dosage , Indoles/metabolism , Intestinal Mucosa/immunology , Intestinal Mucosa/microbiology , Intestinal Mucosa/pathology , Kynurenine/metabolism , Metabolic Networks and Pathways/drug effects , Metabolic Networks and Pathways/immunology , Probiotics/administration & dosage , Proto-Oncogene Proteins c-myc/antagonists & inhibitors , Proto-Oncogene Proteins c-myc/metabolism , Receptors, Aryl Hydrocarbon/antagonists & inhibitors , Receptors, Aryl Hydrocarbon/metabolism , Symbiosis/immunology , Tumor Microenvironment/drug effects , Tumor Microenvironment/immunology
16.
Angew Chem Int Ed Engl ; 60(25): 14013-14021, 2021 06 14.
Article En | MEDLINE | ID: mdl-33768682

The presence of bacteria in the tumor can cause cancer resistance to chemotherapeutics. To fight against bacterium-induced drug resistance, herein we design self-traceable nanoreservoirs that are simultaneously loaded with gemcitabine (an anticancer drug) and ciprofloxacin (an antibiotic) and are decorated with hyaluronic acid for active tumor targeting. The nanoreservoirs have a pH-sensitive gate and an enzyme-responsive gate that can be opened in the acidic and hyaluronidase-abundant tumor microenvironment to control drug release rates. Moreover, the nanoreservoirs can specifically target the tumor regions without eliciting evident toxicity to normal tissues, kill the intratumoral bacteria, and inhibit the tumor growth even in the presence of the bacteria. Unexpectedly, the nanoreservoirs can activate T cell-mediated immune responses through promoting antigen-presenting dendritic cell maturation and depleting immunosuppressive myeloid-derived suppressor cells in bacterium-infected tumors.


Anti-Bacterial Agents/pharmacology , Antimetabolites, Antineoplastic/pharmacology , Ciprofloxacin/pharmacology , Colonic Neoplasms/therapy , Deoxycytidine/analogs & derivatives , Escherichia coli/drug effects , Animals , Anti-Bacterial Agents/chemistry , Antimetabolites, Antineoplastic/chemistry , Cell Line , Ciprofloxacin/chemistry , Colonic Neoplasms/microbiology , Deoxycytidine/chemistry , Deoxycytidine/pharmacology , Drug Resistance, Bacterial/drug effects , Humans , Mice , Gemcitabine
17.
Appl Biochem Biotechnol ; 193(6): 1780-1799, 2021 Jun.
Article En | MEDLINE | ID: mdl-33492552

Dysbiosis of the gut microbiome has been associated with the development of colorectal cancer (CRC). Gut microbiota is involved in the metabolic transformations of dietary components into oncometabolites and tumor-suppressive metabolites that in turn affect CRC development. In a healthy colon, the major of microbial metabolism is saccharolytic fermentation pathways. The alpha-bug hypothesis suggested that oncogenic bacteria such as enterotoxigenic Bacteroides fragilis (ETBF) induce the development of CRC through direct interactions with colonic epithelial cells and alterations of microbiota composition at the colorectal site. Escherichia coli, E. faecalis, F. nucleatum, and Streptococcus gallolyticus showed higher abundance whereas Bifidobacterium, Clostridium, Faecalibacterium, and Roseburia showed reduced abundance in CRC patients. The alterations of gut microbiota may be used as potential therapeutic approaches to prevent or treat CRC. Probiotics such as Lactobacillus and Bifidobacterium inhibit the growth of CRC through inhibiting inflammation and angiogenesis and enhancing the function of the intestinal barrier through the secretion of short-chain fatty acids (SCFAs). Crosstalk between lifestyle, host genetics, and gut microbiota is well documented in the prevention and treatment of CRC. Future studies are required to understand the interaction between gut microbiota and host to the influence and prevention of CRC. However, a better understanding of bacterial dysbiosis in the heterogeneity of CRC tumors should also be considered. Metatranscriptomic and metaproteomic studies are considered a powerful omic tool to understand the anti-cancer properties of certain bacterial strains. The clinical benefits of probiotics in the CRC context remain to be determined. Metagenomic approaches along with metabolomics and immunology will open a new avenue for the treatment of CRC shortly. Dietary interventions may be suitable to modulate the growth of beneficial microbiota in the gut.


Bacteria/metabolism , Colonic Neoplasms , Gastrointestinal Microbiome , Neovascularization, Pathologic , Animals , Colonic Neoplasms/blood supply , Colonic Neoplasms/microbiology , Colonic Neoplasms/therapy , Humans , Neovascularization, Pathologic/microbiology , Neovascularization, Pathologic/therapy
18.
PLoS Pathog ; 17(1): e1009182, 2021 01.
Article En | MEDLINE | ID: mdl-33406160

Streptococcus gallolyticus subspecies gallolyticus (Sgg) has a strong clinical association with colorectal cancer (CRC) and actively promotes the development of colon tumors. However, the molecular determinants involved in Sgg pathogenicity in the gut are unknown. Bacterial type VII secretion systems (T7SS) mediate pathogen interactions with their host and are important for virulence in pathogenic mycobacteria and Staphylococcus aureus. Through genome analysis, we identified a locus in Sgg strain TX20005 that encodes a putative type VII secretion system (designated as SggT7SST05). We showed that core genes within the SggT7SST05 locus are expressed in vitro and in the colon of mice. Western blot analysis showed that SggEsxA, a protein predicted to be a T7SS secretion substrate, is detected in the bacterial culture supernatant, indicating that this SggT7SST05 is functional. Deletion of SggT7SST05 (TX20005Δesx) resulted in impaired bacterial adherence to HT29 cells and abolished the ability of Sgg to stimulate HT29 cell proliferation. Analysis of bacterial culture supernatants suggest that SggT7SST05-secreted factors are responsible for the pro-proliferative activity of Sgg, whereas Sgg adherence to host cells requires both SggT7SST05-secreted and bacterial surface-associated factors. In a murine gut colonization model, TX20005Δesx showed significantly reduced colonization compared to the parent strain. Furthermore, in a mouse model of CRC, mice exposed to TX20005 had a significantly higher tumor burden compared to saline-treated mice, whereas those exposed to TX20005Δesx did not. Examination of the Sgg load in the colon in the CRC model suggests that SggT7SST05-mediated activities are directly involved in the promotion of colon tumors. Taken together, these results reveal SggT7SST05 as a previously unrecognized pathogenicity determinant for Sgg colonization of the colon and promotion of colon tumors.


Cell Proliferation , Colonic Neoplasms/pathology , Gastrointestinal Microbiome , Gastrointestinal Tract/microbiology , Streptococcal Infections/microbiology , Streptococcus gallolyticus subspecies gallolyticus/physiology , Type VII Secretion Systems/metabolism , Animals , Colonic Neoplasms/chemically induced , Colonic Neoplasms/microbiology , Humans , Mice , Mice, Inbred A , Streptococcal Infections/metabolism
19.
IEEE/ACM Trans Comput Biol Bioinform ; 18(5): 1763-1772, 2021.
Article En | MEDLINE | ID: mdl-32816678

Identifying the microbe-disease associations is conducive to understanding the pathogenesis of disease from the perspective of microbe. In this paper, we propose a deep matrix factorization prediction model (DMFMDA) based on deep neural network. First, the disease one-hot encoding is fed into neural network, which is transformed into a low-dimensional dense vector in implicit semantic space via embedding layer, and so is microbe. Then, matrix factorization is realized by neural network with embedding layer. Furthermore, our model synthesizes the non-linear modeling advantages of multi-layer perceptron based on the linear modeling advantages of matrix factorization. Finally, different from other methods using square error loss function, Bayesian Personalized Ranking optimizes the model from a ranking perspective to obtain the optimal model parameters, which makes full use of the unobserved data. Experiments show that DMFMDA reaches average AUCs of 0.9091 and 0.9103 in the framework of 5-fold cross validation and Leave-one-out cross validation, which is superior to three the-state-of-art methods. In case studies, 10, 9 and 9 out of top-10 candidate microbes are verified by recently published literature for asthma, inflammatory bowel disease and colon cancer, respectively. In conclusion, DMFMDA is successful application of deep learning in the prediction of microbe-disease association.


Computational Biology/methods , Deep Learning , Host-Pathogen Interactions/genetics , Asthma/genetics , Asthma/microbiology , Bayes Theorem , Colonic Neoplasms/genetics , Colonic Neoplasms/microbiology , Humans , Inflammatory Bowel Diseases/genetics , Inflammatory Bowel Diseases/microbiology , Neural Networks, Computer
20.
Food Chem ; 334: 127565, 2021 Jan 01.
Article En | MEDLINE | ID: mdl-32717686

The chemical composition, antioxidant activity (AA), cytotoxic activity, antihemolytic effects, and enzyme inhibition (EI) of lyophilized jabuticaba (Myrciaria jaboticaba) seed extract (LJE) was studied. The main compounds found were castalagin, vescalagin, procyanidin A2, and ellagic acid. LJE was more toxic to cancer cells than to normal cells, meaning relative toxicological safety. This cytotoxic effect can be attributed to the pro-oxidant effect observed in the reactive oxygen species (ROS) generation assay. LJE inhibited α-amylase, α-glucosidase, and ACE-I activities and protected human erythrocytes from hemolysis. LJE was incorporated into yogurts at different concentrations and the total phenolic content, AA, and EI increased in a dose-dependent manner. LJE-containing yogurt presented 86% sensory acceptance. The yogurt was administered to Wistar rats bearing cancer and it modulated the gut bacterial microbiota, having a prebiotic effect. LJE is a potential functional ingredient for food companies looking for TPC, AA, and prebiotic effect in vivo.


Colonic Neoplasms/drug therapy , Gastrointestinal Microbiome/drug effects , Myrtaceae/chemistry , Polyphenols/pharmacology , Yogurt , 1,2-Dimethylhydrazine/toxicity , Angiotensin-Converting Enzyme Inhibitors/chemistry , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Animals , Antioxidants/chemistry , Antioxidants/pharmacology , Catechin/analysis , Catechin/pharmacology , Colonic Neoplasms/chemically induced , Colonic Neoplasms/microbiology , Humans , Hydrolyzable Tannins/analysis , Hydrolyzable Tannins/pharmacology , Male , Phenols/analysis , Plant Extracts/analysis , Plant Extracts/chemistry , Plant Extracts/pharmacology , Polyphenols/analysis , Proanthocyanidins/analysis , Proanthocyanidins/pharmacology , Rats, Wistar , Seeds/chemistry , alpha-Amylases/antagonists & inhibitors
...