Colitis-associated Colon Cancer Research Articles

Elevated MMP10/13 mediated barrier disruption and NF-κB activation aggravate colitis and colon tumorigenesis in both individual or full miR-148/152 family knockout mice.

Dynamic miRNA alteration is known to occur in colitis-associated colon cancer (CAC), while the molecular mechanisms underpinning how miRNAs modulate the development from chronic inflammation to CAC is lacking. For the first time, we constructed knockout (KO) mice for individual miR-148/152 family members and entire miR-148/152 family. Based on these KO mice, we conduct the first comprehensive analysis of miR-148/152 family, demonstrating that deficiency of any member of miR-148/152 family aggravate colitis and CAC. Loss of individual miR-148/152 family members or full-family enhance MMP10 and MMP13 expression, causing disruption of intestinal barrier and cleaving pro-TNF-α into bioactive TNF-α fragments to activate NF-κB signaling, thereby aggravating colitis. Individual and full-family deletion also increase accumulation of IKKα and IKKβ, resulting in further hyperactivation of NF-κB signaling, exacerbating colitis and CAC. Moreover, blocking NF-κB signaling exerts a restorative effect on colitis and CAC models only in KO mice. Taken together, these findings demonstrate deleting the full miR-148/152 family or individual members exhibit similar effects in colitis and CAC. Mechanically, miR-148/152 family members deficiency in mice elevates MMP10 and MMP13 to accelerate colitis and CAC via disrupting intestinal barrier function and activating NF-κB signaling, suggesting a potential therapeutic strategy for colitis and CAC.

Clostridium butyricum alleviates dextran sulfate sodium-induced experimental colitis and promotes intestinal lymphatic vessel regeneration in mice

BackgroundInflammatory bowel disease (IBD) is the most common precancerous lesion of colitis-associated colon cancer (CAC). Studies have confirmed that pathological changes in intestinal lymphatic vessels (LVs) significantly promoted the development of IBD-associated carcinogenesis. An imbalance in the microecology of the intestinal flora is a key factor in the progression of IBD. As a result, therapeutic techniques that focus on the relationship between LV regeneration and flora management might be a potential treatment strategy.MethodsWe investigated the role of Clostridium butyricum (C butyricum) in a dextran sulfate sodium (DSS)-induced IBD mouse model. Balb/c mice were given 3% DSS in their drinking water for 8 days to produce acute colitis and simultaneously administrated with C butyricum for 12 days. Hematoxylin and eosin (H&E) staining was used to evaluate the degree of colitis tissue damage. Levels of the lymphatic endothelial cell (LEC)-specific marker LYVE-1 and intestinal expressions of pro-lymphatic vascular endothelial growth factor (VEGF)-C and VEGF-D were determined using immunohistochemical assays.ResultsIn a DSS-induced IBD mouse model, we found that butyric acid-producing C butyricum significantly reduced disease activity index (DAI) scores in mice, reversed the shortening of the colon, weakened the degree of damage to colonic epithelial tissues, inhibited lymphocyte infiltration, and reduced pathological damage to the colon. To our knowledge, this is the first time that tissue expressions of LYVE-1, VEGF-C, and VEGF-D have been seen to increase in IBD-model mice after treatment with C butyricum.ConclusionsOur findings suggest that C butyricum might alleviate IBD in DSS-induced IBD-model mice by promoting intestinal LV regeneration.

Modulation of Gut Microbiota Combined with Upregulation of Intestinal Tight Junction Explains Anti-Inflammatory Effect of Corylin on Colitis-Associated Cancer in Mice.

Inflammatory bowel disease (IBD) involves chronic inflammation, loss of epithelial integrity, and gastrointestinal microbiota dysbiosis, resulting in the development of a colon cancer known as colitis-associated colorectal cancer (CAC). In this study, we evaluated the effects of corylin in a mouse model of dextran sodium sulfate (DSS)-induced colitis. The results showed corylin could improved the survival rate and colon length, maintained body weight, and ameliorated the inflammatory response in the colon. Then, we further identified the possible antitumor effects after 30-day treatment of corylin on an azoxymethane (AOM)/DSS-induced CAC mouse model. Biomarkers associated with inflammation, the colon tissue barrier, macrophage polarization (CD11c, CCR7, CD163, and CD206), and microbiota dysbiosis were monitored in the AOM/DSS group versus corylin groups. Corylin downregulated pro-inflammatory cytokines (TNF-α, IFN-γ, IL-1β, and IL-6) mRNA expression and inflammatory signaling-associated markers (TLR4, MyD88, AP-1, CD11b, and F4/80). In addition, a colon barrier experiment revealed that epithelial cell proliferation of the mucus layer (Lgr5, Cyclin D1, and Olfm4) was downregulated and tight junction proteins (claudin-1 and ZO-1) were upregulated. Furthermore, the Firmicutes/Bacteroidetes ratio changed with corylin intervention, and the microbial diversity and community richness of the AOM/DSS mice were improved by corylin. The comparative analysis of gut microbiota revealed that Bacteroidetes, Patescibacteria, Candidatus Saccharimonas, Erysipelatoclostridium, and Enterorhabdus were significantly increased but Firmicutes, Turicibacter, Romboutsia, and Blautia decreased after corylin treatment. Altogether, corylin administration showed cancer-ameliorating effects by reducing the risk of colitis-associated colon cancer via regulation of inflammation, carcinogenesis, and compositional change of gut microbiota. Therefore, corylin could be a novel, potential health-protective, natural agent against CAC.

HucMSC-Derived Exosomes Alleviate the Deterioration of Colitis via the miR-146a/SUMO1 Axis.

Human umbilical cord mesenchymal stem cell-derived exosome (hucMSC-Ex) plays an important role in tissue repair and immunomodulation, leading to the mitigation of inflammatory bowel disease. However, the preventive function of hucMSC-Ex in the onset and progression of colitis-associated colon cancer (CAC) is poorly understood. In the current study, dextran sodium sulfate/azoxymethane-induced colitis mouse model was established, and the mice disease activity index, body weight, colon length, tumor counts, survival curve, tissue H&E/immunohistochemistry, and cytokines expression were analyzed to evaluate the effects of hucMSC-Ex on CAC. In addition, miR-146a mimics were transfected into colonic epithelial cells (fetal human cells) to evaluate their role in the hucMSC-Ex-mediated regulation of SUMO1. The results showed that hucMSC-Ex inhibits the expression of SUMO1 to reduce the process of CAC progression. Further analysis indicated that miR-146a targets and inhibits SUMO1 expression and its binding to β-catenin. In conclusion, our findings showed that hucMSC-Ex is effective in alleviating the deterioration of colitis via the miR-146a-mediated inhibition of SUMO1, which is crucial in this disease process.

IL-17RD/sef exacerbates experimental mouse colitis and inflammation-associated tumorigenesis by regulating the proportion of T cell subsets.

T helper cells, especially Th1 and Th17 cells, were reported to play a pivotal role in the pathogenesis of inflammatory bowel disease (IBD). However, the underlying factors regulating T cell functions in IBD progression remain to be fully elucidated. Here, we revealed that IL-17RD/Sef exacerbates DSS-induced colitis by regulating the balance of T cell subsets and their secretion of associated cytokines. We also observed that IL-17RD/Sef promotes colitis-associated tumorigenesis and negatively correlates with survival in both mouse and colorectal cancer patients. Our results suggested that IL-17RD/Sef functions as a regulator of T cell subsets to promote the inflammatory responses in the pathogenesis of IBD and colitis-associated colon cancer.

Regulation of gene expression in the development of colitis-associated colon cancer in mice fed a high-fat diet

Studies have shown that the higher prevalence of colorectal cancers among patients with inflammatory bowel disease. Thus, proinflammatory stimulus due to a high-fat diet may impose a higher risk on the development of colorectal cancer. In the present study, we applied a transcriptomic approach to characterize the molecular mechanism(s) by which high-fat feeding aggravates colitis-associated colorectal cancer (CAC). A high-fat diet was supplied in an azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced mouse model for 10 weeks and then the severity of CAC and global gene expression in colon were assessed. Although consumption of high-fat diet did not significantly aggravate CAC, it substantially changed gene expression profile in colon. In AOM/DSS treated mice (AD group) and AD mice fed a high-fat diet (AD + HF group), 34 and 54 DEGs were enriched in ‘pathways in cancer’, respectively. Notably, high-fat diet upregulated the expression of genes associated with spliceosome and ribosome biogenesis, and downregulated the expression of genes associated with lipid catabolism in mice treated with AOM/DSS. In addition, we identified that DEGs between the AD and AD + HF groups, were enriched in ‘metabolic pathways’, especially amino acid and nucleotide metabolism. Taken together, this study provides the molecular mechanism in understanding the high-fat diet-mediated CAC development.

Evening primrose seed extract rich in polyphenols modulates the invasiveness of colon cancer cells by regulating the TYMS expression.

Natural polyphenols are plant metabolites exhibiting a broad range of biological activities. Among them, anticancer properties seem to be very desirable. This study examined the anticancer and anti-metastatic properties of the polyphenol-rich extract from the evening primrose seeds (EPE). In vitro and in vivo studies performed in colorectal cancer (CRC) cell lines and AOM-DSS-induced colitis-associated colon cancer in mice revealed the EPE anticancer properties. Furthermore, we studied the EPE activity on metastatic abilities and showed that the EPE inhibited invasiveness in the following models (cells isolated from patients with different invasive stages and cells with induced invasion by either Snail overexpression or CAF stimulation). More importantly, we also demonstrated that the EPE decreases the cell invasiveness of 5-fluorouracil (5-FU) resistant CRC cells. The inhibition of metastasis correlated with a decrease in thymidylate synthetase (TYMS), which has recently been associated with metastatic phenotype development. Our results indicate that the EPE might be an effective anticancer agent in suppressing colon cancer metastasis regardless of the invasiveness cause. Based on these findings, we concluded that the used EPE extract rich in polyphenols inhibits cell invasion by TYMS downregulation.

Quxie Capsule Alleviates Colitis-associated Colorectal Cancer Through Modulating the Gut Microbiota and Suppressing A. fumigatus-induced Aerobic Glycolysis.

Quxie capsule (QX), a compound of 21 kinds of Traditional Chinese Medicine (TCM) herbs, has been used to treat patients with metastatic colorectal cancer (mCRC) and could suppress the growth of colon cancer. However, the mechanisms of QX inhibiting colorectal cancer remain unclear. In current study, we attempted to determine the anti-colorectal cancer (CRC) effects of QX and the mechanisms of QX in alleviating colorectal cancer. A colitis-associated colon cancer (CAC) model was established by intraperitoneally injecting mice with AOM followed by 3 cycles of 2% DSS in water. During establishment of CAC model, we orally gavaged mice with QX. Hematoxylin and eosin (H&E) and immunohistochemistry were performed to assess lesion of the colonic tumors. The expression of pro-inflammatory cytokines in colonic tumors was measured by qPCR. The proportion of immune cells in colonic tumors was analyzed by flow cytometry. Internal transcribed spacer (ITS) sequencing and 16S rRNA gene sequencing were performed to detect intestinal microbiota. The expression of glycolytic related enzymes, lactate production, and extracellular acidification rate (ECAR) were used to assess the level of aerobic glycolysis. QX markedly inhibited intestinal tumorigenesis by decreasing the expression of pro-inflammatory cytokines and the proportion of myeloid-derived suppressor cells (MDSCs), and increasing the proportion of CD8+ T cells in colon tumors. Fecal microbiota sequencing revealed that QX increased the relative abundances of intestinal symbiotic probiotics, such as, Lactobacillus, Bifidobacterium and Faecalibacterium genera. What's more, opportunistic pathogens, Bacteroides genera and Aspergillus-Aspergillus fumigatus, exhibited remarkably reduced abundances in mice treated with QX compared with untreated CAC mice. Further experiments showed that QX significantly reduced glycolysis of colon tumor and suppressed A. fumigatus-induced glycolytic metabolism of colon cancer cells. QX alleviates the development of CRC at least in part through modulating intestinal microbiota and reducing A. fumigatus-induced aerobic glycolysis of colon cancer cells.

TIPE2 Promotes Tumor Initiation But Inhibits Tumor Progression in Murine Colitis-Associated Colon Cancer.

Colorectal cancer (CRC) is the third leading cause of cancer in the United States, and inflammatory bowel disease patients have an increased risk of developing CRC due to chronic intestinal inflammation with it being the cause of death in 10% to 15% of inflammatory bowel disease patients. TIPE2 (TNF-alpha-induced protein 8-like 2) is a phospholipid transporter that is highly expressed in immune cells and is an important regulator of immune cell function. The azoxymethane/dextran sulfate sodium murine model of colitis-associated colon cancer (CAC) was employed in Tipe2 -/- and wild-type mice, along with colonoid studies, to determine the role of TIPE2 in CAC. Early on, loss of TIPE2 led to significantly less numbers of visible tumors, which was in line with its previously described role in myeloid-derived suppressor cells. However, as time went on, loss of TIPE2 promoted tumor progression, with larger tumors appearing in Tipe2 -/- mice. This was associated with increased interleukin-22/STAT3 phosphorylation signaling. Similar effects were also observed in primary colonoid cultures, together demonstrating that TIPE2 also directly regulated colonocytes in addition to immune cells. This work demonstrates that TIPE2 has dual effects in CAC. In the colonocytes, it works as a tumor suppressor. However, in the immune system, TIPE2 may promote tumorigenesis through suppressor cells or inhibit it through IL-22 secretion. Going forward, this work suggests that targeting TIPE2 for CRC therapy requires cell- and pathway-specific approaches and serves as a cautionary tale for immunotherapy approaches in general in terms of colon cancer, as intestinal inflammation can both promote and inhibit cancer.

Bornlisy Attenuates Colitis-Associated Colorectal Cancer via Inhibiting GPR43-Mediated Glycolysis.

There is evidence that probiotics have a broad antitumor effect in colorectal cancer (CRC). However, the mechanism remains obscure. Here, we investigated the effect of Bornlisy (BO)-cocktails of three probiotics on colitis-associated colon cancer (CAC) and the underlying mechanism. The treatment of CAC mice with BO resulted in decreased tumor loads as compared with their counterparts. BO also inhibited the proliferation and metastasis of CRC cells in vitro. Furthermore, BO inhibited cell proliferation through downregulating glycolysis. Activating glycolysis reversed the protective role of BO in the CAC mice. Mechanically, BO administration promoted the activation of GPR43, followed by its downstream PLC-PKC-ERK pathway, which led to decreased glucose metabolism. These results suggest that BO may provide an intervention strategy for CRC therapy, while GPR43 is a potential targeting receptor during the BO treatment.

Dnmt3a Mutations in the Hematopoietic System Promote Colitis-Associated Colon Cancer: A Model of Clonal Hematopoiesis in Solid Tumors

Clonal hematopoiesis (CH) is a condition wherein hematopoietic stem cells (HSCs) acquire mutations, often in presumed leukemia driver genes such as in DNMT3A, leading to clonal dominance and disproportionate contribution to peripheral blood without overt hematologic abnormalities (Jaiswal et al. 2014). In large cohorts of patients with solid tumors including colorectal cancer, presence of CH is associated with inferior overall survival due to progression of primary malignancy (Coombs et al. 2017). While potential involvement of CH in the pathogenesis of solid tumors driven by unrelated genetic alterations has far-reaching translational implications, the mechanistic understanding of this relationship is lacking.Colorectal cancer is a leading cause of cancer deaths worldwide and can arise from preceding inflammatory bowel disease. More than 20% of patients with colon cancer have detectable CH, which is notably more prevalent than in age-matched general population. We hypothesized that bone marrow-derived cells harboring alterations in DNMT3A, the most commonly disrupted gene in CH (up to 40% of cases), contribute to the pathogenesis of colorectal cancer. To address this, we combined a bone marrow transplantation-based model of CH driven by heterozygous loss of Dnmt3a with a well-established induction of colitis-associated colon cancer (CAC) by azoxymethane (AOM, a carcinogen) and dextran sodium sulfate (DSS, a colitogen). High resolution colonoscopy demonstrated increased colon wall opacity, visible bleeding, numerous fibrin patches and earlier onset of tumor formation with higher penetrance in animals with partial ablation of Dnmt3a in the hematopoietic compartment. Heightened colon pathology was reflected by modified murine endoscopic index of CAC severity (MEICS) (Fung and Putoczki 2018) (MEICS scores 7.5±2.0 in WT vs 10.0±3.2 in Dnmt3a +/-, p=0.05, n=14,13). We observed elevated incidence of tumors >2mm in diameter (40.2±22.2% in WT vs 74.2±15.7% in Dnmt3a +/-, p=0.03, in 5 independent trials) and a higher tumor burden in Dnmt3a +/- chimerae (7.4±7.8 mm 3 in WT vs 14.5±13.9 mm 3 in Dnmt3a +/-, p=0.0017, n=53,55) at end point. Histopathological analysis revealed marked immune infiltration, extensive ulceration and dysplasia of colonic epithelium, and more frequent adenocarcinoma formation with occasional submucosal invasion (histology score 20.2±4.4 in WT vs 24.6±6.9 in Dnmt3a +/-, p=0.03, n=10,9). To uncover signaling pathways deregulated by experimental Dnmt3a-driven CH, we surveyed the auto- and paracrine stimulatory loops by multiplex cytokine/chemokine assays and profiled transcriptomes of colon tumors by bulk RNA-seq. These studies identified gene signatures commonly associated with colon carcinogenesis including accentuated epithelial-to-mesenchymal transition (gene set enrichment analysis (GSEA) NES=2.42, padj=0.0096), Wnt/b-catenin (NES=2.07, padj=0.0096), and Vegf/angiogenesis (NES=1.83, padj=0.0096). Elevated proliferation (Ki67) and increased vascularization (CD31) were validated by immunohistochemistry. These aspects of tumor pathophysiology along with the composition and functional characteristics of the tumor-infiltrating leukocytes derived from animals with and without hematopoietic-specific Dnmt3a partial loss are being further investigated. Preliminary data showed bone marrow-derived macrophages (BMDMs) from Dnmt3a +/- chimera exhibit impaired ability to phagocytose syngeneic MC38 colon tumor cells, compared to WT.Our study provides new insights into the non-tumor-cell-autonomous mechanisms of carcinogenesis effected by alterations in the hematopoietic system and into the interplay between the immune system and the aggressive phenotype of colorectal cancer. Our findings may aid the development of novel therapeutic options to improve outcomes in solid tumor patients with CH. [Display omitted] DisclosuresBowman: Mission Bio: Honoraria, Speakers Bureau. Levine: Ajax: Membership on an entity's Board of Directors or advisory committees; Isoplexis: Membership on an entity's Board of Directors or advisory committees; Gilead: Honoraria; Prelude: Membership on an entity's Board of Directors or advisory committees; Auron: Membership on an entity's Board of Directors or advisory committees; Mission Bio: Membership on an entity's Board of Directors or advisory committees; C4 Therapeutics: Membership on an entity's Board of Directors or advisory committees; Celgene: Research Funding; Zentalis: Membership on an entity's Board of Directors or advisory committees; Imago: Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria; Lilly: Honoraria; QIAGEN: Membership on an entity's Board of Directors or advisory committees; Morphosys: Consultancy; Astellas: Consultancy; Janssen: Consultancy; Incyte: Consultancy; Roche: Honoraria, Research Funding.

Recruitment of M1 Macrophages May Not Be Critical for Protection against Colitis-Associated Tumorigenesis.

A close connection between inflammation and the risk of developing colon cancer has been suggested in the last few years. It has been estimated that patients diagnosed with some types of inflammatory bowel disease, such as ulcerative colitis or Crohn’s disease, have up to a 30% increased risk of developing colon cancer. However, there is also evidence showing that the activation of anti-inflammatory pathways, such as the IL-4 receptor-mediated pathway, may favor the development of colon tumors. Using an experimental model of colitis-associated colon cancer (CAC), we found that the decrease in tumor development in global IL4Rα knockout mice (IL4RαKO) was apparently associated with an inflammatory response mediated by the infiltration of M1 macrophages (F480+TLR2+STAT1+) and iNOS expression in colon tissue. However, when we developed mice with a specific deletion of IL4Rα in macrophages (LysMcreIL4Rα−/lox mice) and subjected them to CAC, it was found that despite presenting a large infiltration of M1 macrophages into the colon, these mice were as susceptible to colon-tumorigenesis as WT mice. These data suggest that in the tumor microenvironment the absence of IL4Rα expression on macrophages, as well as the recruitment of M1 macrophages, may not be directly associated with resistance to developing colon tumors. Therefore, it is possible that IL4Rα expression in other cell types, such as colonic epithelial cells, could have an important role in promoting the development of colitis-associated colon tumorigenesis.

‘Green’ nanotherapeutics from tea leaves for orally targeted prevention and alleviation of colon diseases

Although synthesized nanotherapeutics (NTs) are attractive for the oral treatment of colon diseases, their clinical translations are constrained by the unsatisfactory therapeutic outcomes, potential adverse effects, and high cost of mass production. Here, we report the development of tea leaf-derived natural NTs with desirable particle sizes (140.0 nm) and negative surface charge (−14.6 mV). These natural exosome-like NTs were found to contain large amounts of lipids, some functional proteins, and many bioactive small molecules. Specifically, galactose groups on the surface of NTs could mediate their specific internalization by macrophages via galactose receptor-mediated endocytosis. Moreover, these NTs were able to reduce the production of reactive oxygen species, inhibit the expression of pro-inflammatory cytokines, and increase the amount of anti-inflammatory IL-10 secreted by macrophages. Orally administered NTs could efficiently inhibit the inflammatory bowel responses, restore disrupted colonic barriers and enhance the diversity and overall abundance of gut microbiota, thereby preventing or alleviating inflammatory bowel disease and colitis-associated colon cancer. The present study brings new insights to the facile application of a versatile and robust natural nanoplatform for the prevention and treatment of colon diseases.

Anti-Obesity Drug Orlistat Alleviates Western-Diet-Driven Colitis-Associated Colon Cancer via Inhibition of STAT3 and NF-κB-Mediated Signaling.

Many researchers have argued that Western diet (WD)-induced obesity accelerates inflammation and that inflammation is a link between obesity and colorectal cancer (CRC). This study investigated the effect of WDs on the development and progression of colitis-associated colon cancer (CAC) and the efficacy of the anti-obesity agent orlistat on WD-driven CAC in mice. The results revealed that the WD exacerbated CAC in azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced mice, which showed increased mortality, tumor formation, and aggravation of tumor progression. Furthermore, WD feeding also upregulated inflammation, hyperplasia, and tumorigenicity levels through the activation of STAT3 and NF-κB signaling in an AOM/DSS-induced mouse model. In contrast, treatment with orlistat increased the survival rate and alleviated the symptoms of CAC, including a recovery in colon length and tumor production decreases in WD-driven AOM/DSS-induced mice. Additionally, orlistat inhibited the extent of inflammation, hyperplasia, and tumor progression via the inhibition of STAT3 and NF-κB activation. Treatment with orlistat also suppressed the β-catenin, slug, XIAP, Cdk4, cyclin D, and Bcl-2 protein levels in WD-driven AOM/DSS-induced mice. The results of this study indicate that orlistat alleviates colon cancer promotion in WD-driven CAC mice by suppressing inflammation, especially by inhibiting STAT3 and NF-κB activation.

Inhibitory Effect of Garcinol on Obesity-Exacerbated, Colitis-Mediated Colon Carcinogenesis.

Epidemiological studies show a consistent and compelling association between the risk of colorectal cancer development and obesity, but its mechanisms remain poorly understood. Evidence is mounting that colorectal cancer can be prevented by nutritional supplements, such as phytochemicals. Garcinol, a polyisoprenylated benzophenone derivative, is widely present in Garcinia plants. This study investigates the potential role of garcinol supplementation in ameliorating obesity-induced colon cancer development. An animal model to investigate the effect of high-fat-diet (HFD)-induced obesity on promoting colitis-associated colon cancer (AOM (azoxymethane)/DSS (dextran sodium sulfate)-induced) is designed. The results show that HFD can promote colitis-associated colon cancer as compared to an AOM/DSS group without the intervention of obesity, and supplementing with 0.05% garcinol in the diet can significantly ameliorate obesity-promoted colon carcinogenesis. The results also reveals that the microbiota composition of each group is significantly different and clustered. The most representative genera are Alistipes, Romboutsia, and Ruminococcus. The RNA-sequencing results show that the administration of garcinol can regulate genes and improve obesity-promoting colitis-associated colon carcinogenesis. The study results suggest that garcinol can prevent obesity-promoted colorectal cancer, and these findings provide important niches for the future development of garcinol as functional foods or adjuvant therapeutic agents.

Abstract LB204: HSF1 promotes inflammation induced tumor development through ECM remodeling

Abstract HSF1 promotes inflammation induced tumor development through ECM remodelingAbstractIn the colon, long-term exposure to chronic inflammation drives colitis associated colon cancer (CAC) in patients with inflammatory bowel disease (IBD). Chronic inflammation underlies tumor initiation, promotion, invasion, and metastasis. While the causal and clinical link between chronic inflammation and CAC is well established, we lack a molecular understanding of what is the way in which chronic inflammation leads to develop colon cancer. Within the tumor, cancer cells are surrounded by a variety of non-malignant cells, such as macrophages, endothelial cells, neutrophils, cancer-associated fibroblasts (CAFs), and together with the extracellular matrix (ECM) they compose the tumor microenvironment (TME), also termed the stroma. Even the most aggressive cancers depend and interact with their environment mostly through secreted factors. Unlike cancer cells, stromal cells are genomically stable, and do not harbor oncogenic mutations that could drive their co-evolution and functional reprogramming. Rather, stromal reprogramming is thought to be achieved by transcriptional rewiring. Previous work by us and others has shown that the master regulator heat shock factor 1 (HSF1) plays a crucial role in this process, by mediating a transcriptional program in fibroblasts that enables their reprogramming into cancer-associated fibroblasts (CAFs) to promote malignancy. We hypothesizde that HSF1 plays a crucial role in inflammation-driven cancer by initiation of a transcriptional program that leads to changes in the extracellular matrix (ECM). We found that, in cell culture, cancer-induced ECM assembly by fibroblasts requires HSF1. Using an inflammation-driven cancer model in mice, we measured the changes in proteomic and ECM organization over time. We found that HSF1 drives a transcriptional program that leads to ECM remodeling in early stages and results in development of colon cancer. Loss of HSF1 prevents inflammation-induced ECM remodeling. Further to that, in CAC patients, we found high activation of stromal HSF1 and similarity to our HSF1 proteomic ECM signature in human colorectal cancer driven by HSF1. Thus, HSF1-dependent ECM remodeling mediates the transition from chronic inflammation to colon cancer. Citation Format: Oshrat Levi Galibov, Hagar Lavon, Rina Wassermann-Dozorets, Meirav Pevsner-Fischer, Shimrit Mayer, Esther Wershof, Yaniv Stein, Lauren E. Brown, Wenhan Zhang, Gil Friedman, Reinat Nevo, Ofra Golani, Lior H. Katz, Rona Yaeger, Ido Laish, John A. Porco, Erik Sahai, Dror S Shouval, David Kelsen, Ruth Scherz-Shouval. HSF1 promotes inflammation induced tumor development through ECM remodeling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB204.

Cancer-Preventive Role of Bone Marrow-Derived Mesenchymal Stem Cells on Colitis-Associated Colorectal Cancer: Roles of Gut Microbiota Involved.

BackgroundMesenchymal stem cells (MSCs) treatment showed promising results in inflammatory bowel disease in both rodent models and patients. Nevertheless, previous studies conducted conflicting results on preclinical tumor models treated with MSCs concerning their influence on tumor initiation and progression. This study is designed to demonstrate the role of bone marrow-derived MSCs and the potential mechanism in the colitis-associated colon cancer (CAC) model.MethodsBone marrow-derived MSCs were isolated from green fluorescent protein-transgenic mice, cultured, and identified by flow cytometry. Azoxymethane and dextran sulfate sodium were administrated to establish the CAC mouse model, and MSCs were infused intraperitoneally once per week. The mice were weighed weekly, and colon length, tumor number, and average tumor size were assessed after the mice were killed. MSC localization was detected by immunofluorescence staining; tumor cell proliferation and apoptosis were measured by immunohistochemistry staining of Ki-67 and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling assay, respectively. The colonic tumor tissues were isolated for RNA-seq, and fecal samples were collected for 16S ribosomal RNA sequencing of the microbiome.ResultsAfter injection intraperitoneally, MSCs migrated to the intestine and inhibited the initiation of colitis-associated colorectal cancer. This inhibition effect was marked by less weight loss, longer colon length, and reduced tumor numbers. Moreover, MSCs reduced tumor cell proliferation and induced tumor cell apoptosis. Furthermore, MSCs could inhibit chronic inflammation assessed by RNA-sequencing and promote gut microbiome normalization detected by 16S ribosomal RNA sequencing.ConclusionThe results proved that MSCs could migrate to the colon, inhibit chronic inflammation, and regulate gut microbiome dysbiosis to suppress the development of CAC.

CGAS restricts colon cancer development by protecting intestinal barrier integrity

The DNA-sensing enzyme cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS) regulates inflammation and immune defense against pathogens and malignant cells. Although cGAS has been shown to exert antitumor effects in several mouse models harboring transplanted tumor cell lines, its role in tumors arising from endogenous tissues remains unknown. Here, we show that deletion of cGAS in mice exacerbated chemical-induced colitis and colitis-associated colon cancer (CAC). Interestingly, mice lacking cGAS were more susceptible to CAC than those lacking stimulator of interferon genes (STING) or type I interferon receptor under the same conditions. cGAS but not STING is highly expressed in intestinal stem cells. cGAS deficiency led to intestinal stem cell loss and compromised intestinal barrier integrity upon dextran sodium sulfate-induced acute injury. Loss of cGAS exacerbated inflammation, led to activation of STAT3, and accelerated proliferation of intestinal epithelial cells during CAC development. Mice lacking cGAS also accumulated myeloid-derived suppressive cells within the tumor, displayed enhanced Th17 differentiation, but reduced interleukin (IL)-10 production. These results indicate that cGAS plays an important role in controlling CAC development by defending the integrity of the intestinal mucosa.

Rosmarinic acid represses colitis-associated colon cancer: A pivotal involvement of the TLR4-mediated NF-κB-STAT3 axis

Previously, we found that rosmarinic acid (RA) exerted anti-inflammatory activities in a dextran sulfate sodium (DSS)-induced colitis model. Here, we investigated the anti-tumor effects of RA on colitis-associated colon cancer (CAC) and the underlying molecular mechanisms. We established an azoxymethane (AOM)/DSS-induced CAC murine model for in vivo studies and used a conditioned media (CM) culture system in vitro. H&E staining, immunohistochemistry, western blot assay, enzyme-linked immunosorbent assay, molecular docking, co-immunoprecipitation, and immunofluorescence assay were utilized to investigate how RA prevented colorectal cancer. In the AOM/DSS-induced CAC murine model, RA significantly reduced colitis severity, inflammation-related protein expression, tumor incidence, and colorectal adenoma development. It significantly modulated toll-like receptor-4 (TLR4)-mediated nuclear factor-kappa B (NF-κB) and signal transducer and activator of transcription 3 (STAT3) activation, thus attenuating the expression of anti-apoptotic factors, which mediate transcription factor-dependent tumor growth. In vitro, RA inhibited CM-induced TLR4 overexpression and competitively inhibited TLR4-myeloid differentiation factor 2 complex in an inflammatory microenvironment. Thus, RA suppressed NF-κB and STAT3 activation in colon cancer cells in an inflammatory microenvironment. Therefore, RA suppressed colitis-associated tumorigenesis in the AOM/DSS-induced CAC murine model and abrogated human colon cancer progression in an inflammatory microenvironment by propitiating TLR4-mediated NF-κB and STAT3 activation, pleiotropically.

Oroxylin A maintains the colonic mucus barrier to reduce disease susceptibility by reconstituting a dietary fiber-deprived gut microbiota.

Dietary fiber intake helps to maintain gut homeostasis. Fiber deficiency causes commensals to utilize mucins as an energy source to destroy mucus layer, thus promoting susceptibility to inflammatory bowel disease. Here, we reported that oroxylin A, a natural flavonoid, ameliorated low-grade colonic inflammation caused by fiber deficiency, alleviated colitis, and further prevented colitis-associated colon cancer in mice. The anti-inflammatory effect of oroxylin A was due to its alteration of gut microbiota. We found that the levels of Eubacterium coprostanoligenes was significantly increased by oroxylin A and the colonized Eubacterium coprostanoligenes significantly protected against colitis and carcinogenesis in colon of mice. Together, our results in this study suggest that oroxylin A may reduce the susceptibility to intestinal diseases by increasing the level of Eubacterium coprostanoligenes which could provide a therapeutic alternation for the treatment of intestinal diseases.