Project description:Our work showed decreased hepatic levels of TDCA in the C26 model of cancer cachexia. We also found gut microbiota composition alterations in cachectic C26 mice, as well as reductions in microbial 7α-dehydroxylase activity, and activity of 7α-HSDH and 12α-HSDH, which drive the production of secondary bile acids. Finally, we showed that TDCA administration induces lower hepatic levels of cholesterol in C26 mice. Published in Thibaut et al, Gut Microbes 2025
Project description:Colorectal cancer is a leading cause of cancer-related deaths. Mutations in the innate immune receptor AIM2 are frequently identified in patients with colorectal cancer, but how AIM2 modulates colonic tumorigenesis is unknown. Here, we found that Aim2-deficient mice were hypersusceptible to colonic tumor development. Production of inflammasome-associated cytokines and other inflammatory mediators were largely intact in Aim2-deficient mice, however, intestinal stem cells were prone to uncontrolled proliferation. Aberrant Wnt signaling expanded a population of tumor-initiating stem cells in the absence of AIM2. Susceptibility of Aim2-deficient mice to colorectal tumorigenesis was enhanced by a dysbiotic gut microbiota, which was reduced by reciprocal exchange of gut microbiota with wild-type healthy mice. These findings uncover a synergy between a specific host genetic factor and gut microbiota in determining the susceptibility to colorectal cancer. Therapeutic modulation of AIM2 expression and microbiota has the potential to prevent colorectal cancer. We used microarrays to compare the transcriptome Aim2 deficent mice to wild type mice in colon tumor and colitis samples. Here were 12 mice in total, 3 for each genotype and tissue combination.
Project description:Colorectal cancer is a leading cause of cancer-related deaths. Mutations in the innate immune receptor AIM2 are frequently identified in patients with colorectal cancer, but how AIM2 modulates colonic tumorigenesis is unknown. Here, we found that Aim2-deficient mice were hypersusceptible to colonic tumor development. Production of inflammasome-associated cytokines and other inflammatory mediators were largely intact in Aim2-deficient mice, however, intestinal stem cells were prone to uncontrolled proliferation. Aberrant Wnt signaling expanded a population of tumor-initiating stem cells in the absence of AIM2. Susceptibility of Aim2-deficient mice to colorectal tumorigenesis was enhanced by a dysbiotic gut microbiota, which was reduced by reciprocal exchange of gut microbiota with wild-type healthy mice. These findings uncover a synergy between a specific host genetic factor and gut microbiota in determining the susceptibility to colorectal cancer. Therapeutic modulation of AIM2 expression and microbiota has the potential to prevent colorectal cancer.
Project description:Colorectal cancer (CRC) is closely related to gut dysbiosis. We investigated the effects of imbalanced gut microbiota on the progression of intestinal adenoma in Apcmin/+ mice model using fecal microbiota transplantation (FMT). Administration of feces from CRC patients increased tumor proliferation and decreased apoptosis in tumor cells. Abnormal expression of genes related to Wnt-protein binding and lipid metabolic process was observed.
Project description:Chronic inflammation and gut microbiota dysbiosis are risk factors for colorectal cancer. In clinical practice, inflammatory bowel disease (IBD) patients have a greatly increased risk of developing colitis associated colorectal cancer (CAC). However, the basis underlying the initiation of CAC remains to be explored. Systematic filtration through existing genome-wide association study (GWAS) and conditional deletion of Zfp90 in CAC mice model indicated that Zfp90 was a putative oncogene in CAC development. Strikingly, depletion of gut microbiota eliminated the tumorigenic effect of Zfp90 in CAC mice model. Moreover, fecal microbiota transplantation demonstrated Zfp90 promoted CAC depending on gut microbiota. Combining 16s rDNA sequencing in feces specimens from CAC mice model, we speculated that Prevotella copri-defined microbiota might mediate the oncogenic role of Zfp90 in the development of CAC. Mechanistic studies revealed Zfp90 accelerated CAC development through Tlr4-Pi3k-Akt-Nf-κb pathway. Our findings elucidated the crucial role of Zfp90-microbiota-Nf-κb axis in creating a tumor-promoting environment and suggested therapeutic targets for CAC prevention and treatment.
Project description:Gut microbial dysbiosis can play a causal role of in colorectal cancer. Gut microbiota chnages with age and becomes moer pro-inflammatory. We sought to determine whether microbiota from Old donors promotes more tumor formation in recipients than meterial from young donors.
Project description:Gut microbial dysbiosis can play a causal role of in colorectal cancer. Gut microbiota chnages with age and becomes moer pro-inflammatory. We sought to determine whether microbiota from Old donors promotes more tumor formation in recipients than meterial from young donors.
Project description:Alterations in gut microbiota have been implicated in the pathogenesis of Colorectal Cancer (CRC). Here we collected fecal samples from 14 CRC patients and 14 healthy volunteer cohorts, and characterized their microbiota using label-free quantitative metaproteomics method. We have quantified 30,062 gut microbial protein groups, 91,902 peptides, and 195 genera of microbes, among which 341 proteins were found significantly different in abundance between the CRC patients and healthy volunteers. Our study demonstrates that gut bacteria involve in CRC pathogenesis not only via taxonomy abundance variations but also functional activity changes.
Project description:Pancreatic cancer is the 3rd most prevalent cause of cancer related deaths in United states alone, with over 55000 patients being diagnosed in 2019 alone and nearly as many succumbing to it. Late detection, lack of effective therapy and poor understanding of pancreatic cancer systemically contributes to its poor survival statistics. Obesity and high caloric intake linked co-morbidities like type 2 diabetes (T2D) have been attributed as being risk factors for a number of cancers including pancreatic cancer. Studies on gut microbiome has shown that lifestyle factors as well as diet has a huge effect on the microbial flora of the gut. Further, modulation of gut microbiome has been seen to contribute to effects of intensive insulin therapy in mice on high fat diet. In another study, abnormal gut microbiota was reported to contribute to development of diabetes in Db/Db mice. Recent studies indicate that microbiome and microbial dysbiosis plays a role in not only the onset of disease but also in its outcome. In colorectal cancer, Fusobacterium has been reported to promote therapy resistance. Certain intra-tumoral bacteria have also been shown to elicit chemo-resistance by metabolizing anti-cancerous agents. In pancreatic cancer, studies on altered gut microbiome have been relatively recent. Microbial dysbiosis has been observed to be associated with pancreatic tumor progression. Modulation of microbiome has been shown to affect response to anti-PD1 therapy in this disease as well. However, most of the studies in pancreatic cancer and microbiome have remained focused om immune modulation. In the current study, we observed that in a T2D mouse model, the microbiome changed significantly as the hyperglycemia developed in these animals. Our results further showed that, tumors implanted in the T2D mice responded poorly to Gemcitabine/Paclitaxel (Gem/Pac) standard of care compared to those in the control group. A metabolomic reconstruction of the WGS of the gut microbiota further revealed that an enrichment of bacterial population involved in drug metabolism in the T2D group.