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:Colitis-associated colorectal cancer (CAC) is a serious complication of inflammatory bowel disease (IBD) with complex etiology involving chronic inflammation, immune dysregulation, and gut microbiota dysbiosis. Creatine, a natural nitrogenous com-pound, possesses anti-inflammatory and immunomodulatory properties, but its role in CAC remains unclear.We established an AOM/DSS-induced mouse model of CAC and supplemented mice with creatine. We assessed the effects of creatine on colitis severity, tumor burden, and histopathology. Additionally, we investigated the impact of crea-tine on gut barrier function, macrophage polarization, and gut microbiota composi-tion.Creatine supplementation significantly alleviated DSS-induced colitis, reduced tumor burden, and delayed CAC progression in mice. Mechanistically, creatine im-proved gut barrier function by protecting tight junction proteins from degradation in-duced by the modeling stimulus,influenced macrophage polarization, and main-tained gut microbiota diversity, promoting the abundance of beneficial bacteria while reducing harmful ones.Our findings suggest that creatine supplementation may rep-resent a promising supportive therapy for IBD and CAC by modulating the gut micro-biota and immune microenvironment. Further investigation is warranted to explore the clinical potential of creatine in the management of CAC.
Project description:Chronic inflammation underlies tumor initiation, progression, invasion, and metastasis. In the colon, long-term exposure to chronic inflammation drives colitis associated colon cancer (CAC) in patients with inflammatory bowel disease (IBD). While the causal and clinical links between chronic inflammation and CAC are well established, our molecular understanding of how chronic inflammation leads to the development of colon cancer is still lacking. Here we deconstruct the evolving microenvironment of CAC, by measuring proteomic changes and extracellular matrix (ECM) organization over time in a genetically modified mouse model of CAC. We detect early changes in ECM structure and composition, and report that the transcriptional regulator heat shock factor 1 (HSF1) plays a crucial role in orchestrating these events. Activated in stromal fibroblasts of the gut, HSF1 promotes ECM remodeling and inflammatory programs which lead to the development of CAC. Loss of HSF1 abrogates ECM assembly by colon fibroblasts in cell culture, prevents inflammation-induced ECM remodeling in mice and significantly inhibits progression to CAC. Establishing the relevance of our experimental findings to human disease, we find high activation of stromal HSF1 in CAC patients, and detect the HSF1-dependent proteomic ECM signature in human colorectal cancer. Thus, HSF1-dependent ECM remodeling plays a crucial role in mediating inflammation-driven colon cancer.
Project description:In this study we performed MeRIP-Seq to study N6-methyl adenosine (m6A) and and N6,2′ -O-dimethyladenosine (m6Am) modification of mRNA. We investigated the effect of the microbiota on the transcriptome and epitranscriptomic modifications in murine liver and cecum. We compared m6A/m modification profiles in cecum of conventionally raised (CONV) and germ-free (GF) mice. We additionally included GF mice colonised with the flora of CONV mice for four weeks (ex-GF), for which show that they exhibit similar patterns of the most abundant genera of gut bacteria as CONV mice. We added mice treated with several antibiotics to deplete the gut flora (abx)and vancomycin treated mice in which the genera Akkermansia, Escherichia/Shigella and Lactobacillus were enriched. Furthermore, we included GF mice colonised with the commensal bacterium Akkermansia muciniphila (Am), Lactobacillus plantarum (Lp) and Escherichia coli Nissle (Ec) and analysed their m6A/m modification profiles. In addition, we analysed changes in m6A/m- modified liver RNA for CONV, GF, and Am, Lp and Ec mice.
Project description:Chronic inflammation underlies tumor initiation, progression, invasion, and metastasis. In the colon, long-term exposure to chronic inflammation drives colitis associated colon cancer (CAC) in patients with inflammatory bowel disease (IBD). While the causal and clinical links between chronic inflammation and CAC are well established, our molecular understanding of how chronic inflammation leads to the development of colon cancer is still lacking. Here we deconstruct the evolving microenvironment of CAC, by measuring proteomic changes and extracellular matrix (ECM) organization over time in a genetically modified mouse model of CAC. We detect early changes in ECM structure and composition, and report that the transcriptional regulator heat shock factor 1 (HSF1) plays a crucial role in orchestrating these events. Activated in stromal fibroblasts of the gut, HSF1 promotes ECM remodeling and inflammatory programs which lead to the development of CAC. Loss of HSF1 abrogates ECM assembly by colon fibroblasts in cell culture, prevents inflammation-induced ECM remodeling in mice and significantly inhibits progression to CAC. Establishing the relevance of our experimental findings to human disease, we find high activation of stromal HSF1 in CAC patients, and detect the HSF1-dependent proteomic ECM signature in human colorectal cancer. Thus, HSF1-dependent ECM remodeling plays a crucial role in mediating inflammation-driven colon cancer.
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.