Blocking TNF-alpha in mice reduces colorectal carcinogenesis associated with chronic colitis

Trichomicin Suppresses Colorectal Cancer via Comprehensive Regulation of IL-6 and TNFα in Tumor Cells, TAMs, and CAFs

Trichomicin, a small-molecule compound isolated from fungi, has been identified with bioactivity of antitumor. In this study, a colon cancer subcutaneous mice model was used to evaluate the antitumor effects of Trichomicin in vivo. Treatment with Trichomicin significantly inhibited tumor growth in a xenograft mouse colon cancer model. The underlying molecular mechanism has also been investigated through the quantification of relevant proteins. The expression levels of IL-6 and TNFα were reduced in tumor tissues of mice treated with Trichomicin, which was consistent with results of in vitro experiments in which Trichomicin suppressed the expression of IL-6 and TNFα in tumor and stromal cells. In addition, Trichomicin inhibited TNFα-induced activation of NF-κB and basal Stat3 signaling in vitro, which resulted in reduced expression of the immune checkpoint protein PD-L1 in tumor and stromal cells. Conclusively, Trichomicin, a promising new drug candidate with antitumor activity, exerted antitumor effects against colon cancer through inhibition of the IL-6 and TNFα signaling pathways.

Tumor Necrosis Factor α Blockade: An Opportunity to Tackle Breast Cancer

Breast cancer is the most frequently diagnosed cancer and the principal cause of mortality by malignancy in women and represents a main problem for public health worldwide. Tumor necrosis factor α (TNFα) is a pro-inflammatory cytokine whose expression is increased in a variety of cancers. In particular, in breast cancer it correlates with augmented tumor cell proliferation, higher malignancy grade, increased occurrence of metastasis and general poor prognosis for the patient. These characteristics highlight TNFα as an attractive therapeutic target, and consequently, the study of soluble and transmembrane TNFα effects and its receptors in breast cancer is an area of active research. In this review we summarize the recent findings on TNFα participation in luminal, HER2-positive and triple negative breast cancer progression and metastasis. Also, we describe TNFα role in immune response against tumors and in chemotherapy, hormone therapy, HER2-targeted therapy and anti-immune checkpoint therapy resistance in breast cancer. Furthermore, we discuss the use of TNFα blocking strategies as potential therapies and their clinical relevance for breast cancer. These TNFα blocking agents have long been used in the clinical setting to treat inflammatory and autoimmune diseases. TNFα blockade can be achieved by monoclonal antibodies (such as infliximab, adalimumab, etc.), fusion proteins (etanercept) and dominant negative proteins (INB03). Here we address the different effects of each compound and also analyze the use of potential biomarkers in the selection of patients who would benefit from a combination of TNFα blocking agents with HER2-targeted treatments to prevent or overcome therapy resistance in breast cancer.

Stage predictivity of neutrophil/lymphocyte and platelet/lymphocyte ratios in pancreatic neuroendocrine tumors

Objectives

This study aimed to analyze the correlations between European Neuroendocrine Tumor Society (ENEST), Tumor Node Metastasis (TNM) staging systems and pre-operative neutrophil/lymphocyte (NLR) and platelet/lymphocyte ratios (PLR) in patients with pancreatic neuroendocrine tumor (PNET).

Material and Methods

Forty-four patients with diagnosed PNET were analyzed retrospectively. Accordingly, the patients' blood and clinicopathological parameters were analyzed. The correlations between laboratory parameters and tumor stages were evaluated using Eta correlation analysis. The control group was composed of volunteering healthy participants who had similarities with our study group as regards age and gender.

Results

According to ENETS classification, 34% of the patients were stage I, 25% were stage II, 20.4% were stage III and 20.4% were stage IV. NLR and PLR mean values were 2.4 and 127, respectively. NLR values of the patients in the study group were higher than those of the control group (p= 0.001). NLR and PLR values of stage I, II, III and IV patients tended to increase in parallel to the higher stages according to ENETS system (p= 0.0001 and p= 0.0001, respectively). Similarly, NLR and PLR values increased in parallel to the higher stages according to TNM system (p= 0.0001 and p= 0.0001, respectively). In addition, NLR values were found to be higher in patients with lymph node metastasis than in those without (p= 0.001).

Conclusion

Increased levels of inflammatory mediators such as NLR and PLR are associated with advanced stages of patients with PNET.

Regulatory T cells specifically suppress conventional CD8αβ T cells in intestinal tumors of APCMin/+ mice

The presence of activated T cells in colorectal cancer tissues is a strong predictor of patient survival. Our previous studies have shown that regulatory T cells (Treg) are able to reduce T cell transendothelial migration in vitro and accumulation of effector T cells in intestinal tumors in vivo in the murine APC^Min/+ model for microsatellite stable intestinal tumors. In this study, we investigated the effect of Treg depletion on the density and effector functions of different TCRαβ⁺ and TCRγδ⁺ T cell populations in intestinal tumors. We used the APC^Min/+\DEREG mouse model, which harbor a diphtheria toxin receptor under the control of the FOXP3 promoter, to deplete Treg in tumor bearing mice. We found that the density of conventional TCRαβ⁺CD8αβ⁺ T cells was significantly increased in Treg-depleted tumors in comparison with Treg-proficient tumors. Furthermore, TCRαβ⁺CD8αβ⁺ T cells showed increased proliferation and activation as well as increased Granzyme B and IFN-γ production in Treg-depleted tumors. In sharp contrast, the densities and effector functions of TCRαβ⁺CD8αα⁺ T cells and TCRγδ⁺ T cells remained unchanged by Treg depletion. We also documented a distinct population of IL-17A⁺TNF⁺ TCRγδ⁺CD8⁻ T cells in tumors, which were not affected by Treg depletion. We conclude that Treg depletion affects only conventional TCRαβ⁺CD8αβ⁺ T cells in intestinal tumors, while unconventional T cells and T cells in unaffected tissue are not altered. Immunotherapies aimed at depleting Treg from tumors may thus be a viable option for reinvigoration of conventional cytotoxic T cells with a Th1 cytokine profile.

Angiogenin regulates PKD activation and COX-2 expression induced by TNF-α and bradykinin in the colonic myofibroblast

INTRODUCTION

The myofibroblast is a gastrointestinal stromal cell that is a target of tumor necrosis factor-alpha (TNF-α), a pro-inflammatory cytokine strongly implicated in colitis-associated cancer. Crosstalk between TNF-α and other pro-inflammatory mediators amplify inflammatory signaling but the mechanism is unknown. Angiogenin (ANG) is a 14-kDa angiogenesis protein that is regulated in patients with inflammatory bowel disease. However, the role of ANG on inflammatory mediator crosstalk in the myofibroblast is unknown.

METHODS

The human colonic myofibroblast cell line 18Co, as well as primary mouse and human colonic myofibroblasts, were exposed to TNF-α (10 ng/ml) and bradykinin (BK, 100 nM). ANG was quantified by ELISA. The expression of cyclo-oxygenase-2 (COX-2) and phosphorylation of PKD was assessed by Western Blot.

RESULTS

Primary mouse and human colonic myofibroblasts exposed to TNF-α/BK led to enhanced PKD phosphorylation and synergistic COX-2 expression. 18Co cells secrete high levels of ANG (24h, 265 ± 5 pg/ml). The monoclonal antibody 26-2F, which neutralizes ANG, inhibited TNF-α/BK-mediated PKD phosphorylation and synergistic COX-2 expression in primary human myofibroblasts. Likewise, in primary mouse myofibroblasts that do not express ANG (ANG-KO), TNF-α/BK failed to enhance PKD phosphorylation and COX-2 expression.

CONCLUSIONS

TNF-α/BK enhance PKD phosphorylation and COX-2 expression in primary mouse and human colonic myofibroblasts. Angiogenin is produced by the myofibroblast, and inhibition of ANG signaling, either by its absence (ANG-KO) or by pharmacologic inhibition, blocks enhanced PKD phosphorylation and synergistic COX-2 expression induced by TNF-α/BK. ANG mediates crosstalk signaling between TNF-α/BK in the regulation of stroma-derived COX-2 and may be a novel therapeutic target for the management of colitis-associated cancer.

Toll-Interacting Protein Regulates Immune Cell Infiltration and Promotes Colitis-Associated Cancer

Expression of Toll-interacting protein (Tollip), a potent TLR modulator, decreases in patients with inflammatory bowel diseases (IBD), whereas Tollip^−/− mice are susceptible to colitis. Tollip expression was shown to be reduced in sporadic adenoma . In contrast, we found variable Tollip expression in patients with colitis-associated adenomas. In Tollip^−/− mice challenged to develop colitis-associated cancer (CAC), tumor formation was significantly reduced owing to decreased mucosal proliferative and apoptotic indexes. This protection was associated with blunt inflammatory responses without significant changes in microbial composition. mRNA expression of Cd62l and Ccr5 homing receptors was reduced in colons of untreated Tollip^−/− mice, whereas CD62L⁺ CD8⁺ T cells accumulated in the periphery. In Tollip-deficient adenomas Ctla-4 mRNA expression and tumor-infiltrating CD4⁺ Foxp3⁺ regulatory T cell (Treg) were decreased. Our data show that protection from CAC in Tollip-deficient mice is associated with defects in lymphocyte accumulation and composition in colitis-associated adenomas.

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Tollip protects from colitis but promotes colitis-associated cancer onset

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Tollip-deficient tumors demonstrate decreased cell turnover and inflammation

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Tollip ablation favors naive CD8⁺ T cell accumulation in peripheral lymphoid organs

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Regulatory T cell accumulation is aberrant in Tollip-deficient tumors

Cordyceps militaris induces apoptosis in ovarian cancer cells through TNF-α/TNFR1-mediated inhibition of NF-κB phosphorylation

BACKGROUND

Cordyceps militaris (L.) Fr. (C. militaris) exhibits pharmacological activities, including antitumor properties, through the regulation of the nuclear factor kappa B (NF-κB) signaling. Tumor Necrosis Factor (TNF) and TNF-α modulates cell survival and apoptosis through NF- κB signaling. However, the mechanism underlying its mode of action on the NF-κB pathway is unclear.

METHODS

Here, we analyzed the effect of C. militaris extract (CME) on the proliferation of ovarian cancer cells by confirming viability, morphological changes, migration assay. Additionally, CME induced apoptosis was determined by apoptosis assay and apoptotic body formation under TEM. The mechanisms of CME were determined through microarray, immunoblotting and immunocytochemistry.

RESULTS

CME reduced the viability of cells in a dose-dependent manner and induced morphological changes. We confirmed the decrease in the migration activity of SKOV-3 cells after treatment with CME and the consequent induction of apoptosis. Immunoblotting results showed that the CME-mediated upregulation of tumor necrosis factor receptor 1 (TNFR1) expression induced apoptosis of SKOV-3 cells via the serial activation of caspases. Moreover, CME negatively modulated NF-κB activation via TNFR expression, suggestive of the activation of the extrinsic apoptotic pathway. The binding of TNF-α to TNFR results in the disassociation of IκB from NF-κB and the subsequent translocation of the active NF-κB to the nucleus. CME clearly suppressed NF-κB translocation induced by interleukin (IL-1β) from the cytosol into the nucleus. The decrease in the expression levels of B cell lymphoma (Bcl)-xL and Bcl-2 led to a marked increase in cell apoptosis.

CONCLUSION

These results suggest that C. militaris inhibited ovarian cancer cell proliferation, survival, and migration, possibly through the coordination between TNF-α/TNFR1 signaling and NF-κB activation. Taken together, our findings provide a new insight into a novel treatment strategy for ovarian cancer using C. militaris.

Bone marrow niche-derived extracellular matrix-degrading enzymes influence the progression of B-cell acute lymphoblastic leukemia

Specific and reciprocal interactions with the bone marrow microenvironment (BMM) govern the course of hematological malignancies. Matrix metalloproteinase-9 (MMP-9), secreted by leukemia cells, facilitates tumor progression via remodeling of the extracellular matrix (ECM) of the BMM. Hypothesizing that leukemias may instruct the BMM to degrade the ECM, we show, that MMP-9-deficiency in the BMM prolongs survival of mice with BCR-ABL1-induced B-cell acute lymphoblastic leukemia (B-ALL) compared with controls and reduces leukemia-initiating cells. MMP-9-deficiency in the BMM leads to reduced degradation of proteins of the ECM and reduced invasion of B-ALL. Using various in vivo and in vitro assays, as well as recipient mice deficient for the receptor for tumor necrosis factor (TNF) α (TNFR1) we demonstrate that B-ALL cells induce MMP-9-expression in mesenchymal stem cells (MSC) and possibly other cells of the BMM via a release of TNFα. MMP-9-expression in MSC is mediated by activation of nuclear factor kappa B (NF-κB) downstream of TNFR1. Consistently, knockdown of TNF-α in B-ALL-initiating cells or pharmacological inhibition of MMP-9 led to significant prolongation of survival in mice with B-ALL. In summary, leukemia cell-derived Tnfα induced MMP-9-expression by the BMM promoting B-ALL progression. Inhibition of MMP-9 may act as an adjunct to existing therapies.

Noncoding RNAs in inflammation and colorectal cancer

Despite advanced clinical treatments, mortality in patients with metastatic colorectal cancer (CRC) remains high. Three critical determinants in CRC progression include the epithelial proliferation checkpoints, epithelial-to-mesenchymal transition (EMT) and inflammatory cytokines in the tumour microenvironment. Genes involved in these three processes are regulated at the transcriptional and post-transcriptional level. Recent studies revealed previously unappreciated roles of non-coding ribonucleic acids (ncRNAs) in modulating the proliferation checkpoints, EMT, and inflammatory gene expression in CRC. In this review, we will discuss the mechanisms underlying the roles of ncRNAs in CRC as well as examine future perspectives in this field. Better understanding of ncRNA biology will provide novel targets for future therapeutic development.

Cancer Cell-Derived Granulocyte-Macrophage Colony-Stimulating Factor Is Dispensable for the Progression of 4T1 Murine Breast Cancer

We previously reported that 4T1 murine breast cancer cells produce GM-CSF that up-regulates macrophage expression of several cancer promoting genes, including Mcp-1/Ccl2, Ccl17 and Rankl, suggesting a critical role of cancer cell-derived GM-CSF in cancer progression. Here, we attempted to define whether 4T1 cell-derived GM-CSF contributes to the expression of these genes by 4T1tumors, and their subsequent progression. Intraperitoneal injection of anti-GM-CSF neutralizing antibody did not decrease the expression of Mcp-1, Ccl17 or Rankl mRNA by 4T1 tumors. To further examine the role of cancer cell-derived GM-CSF, we generated GM-CSF-deficient 4T1 cells by using the Crisper-Cas9 system. As previously demonstrated, 4T1 cells are a mixture of cells and cloning of cells by itself significantly reduced tumor growth and lung metastasis. By contrast, GM-CSF-deficiency did not affect tumor growth, lung metastasis or the expression of these chemokine and cytokine genes in tumor tissues. By in-situ hybridization, the expression of Mcp-1 mRNA was detected in both F4/80-expressing and non-expressing cells in tumors of GM-CSF-deficient cells. These results indicate that cancer cell-derived GM-CSF is dispensable for the tuning of the 4T1 tumor microenvironment and the production of MCP-1, CCL17 or RANKL in the 4T1 tumor microenvironment is likely regulated by redundant mechanisms.

Cross-talk between Colon Cells and Macrophages Increases ST6GALNAC1 and MUC1-sTn Expression in Ulcerative Colitis and Colitis-Associated Colon Cancer

Patients with ulcerative colitis have an increased risk of developing colitis-associated colon cancer (CACC). Changes in glycosylation of the oncoprotein MUC1 commonly occur in chronic inflammation, including ulcerative colitis, and this abnormally glycosylated MUC1 promotes cancer development and progression. It is not known what causes changes in glycosylation of MUC1. Gene expression profiling of myeloid cells in inflamed and malignant colon tissues showed increased expression levels of inflammatory macrophage-associated cytokines compared with normal tissues. We analyzed the involvement of macrophage-associated cytokines in the induction of aberrant MUC1 glycoforms. A coculture system was used to examine the effects of M1 and M2 macrophages on glycosylation-related enzymes in colon cancer cells. M2-like macrophages induced the expression of the glycosyltransferase ST6GALNAC1, an enzyme that adds sialic acid to O-linked GalNAc residues, promoting the formation of tumor-associated sialyl-Tn (sTn) O-glycans. Immunostaining of ulcerative colitis and CACC tissue samples confirmed the elevated number of M2-like macrophages as well as high expression of ST6GALNAC1 and the altered MUC1-sTn glycoform on colon cells. Cytokine arrays and blocking antibody experiments indicated that the macrophage-dependent ST6GALNAC1 activation was mediated by IL13 and CCL17. We demonstrated that IL13 promoted phosphorylation of STAT6 to activate transcription of ST6GALNAC1. A computational model of signaling pathways was assembled and used to test IL13 inhibition as a possible therapy. Our findings revealed a novel cellular cross-talk between colon cells and macrophages within the inflamed and malignant colon that contributes to the pathogenesis of ulcerative colitis and CACC.See related Spotlight on p. 160.

Inflammation and Cancer: Triggers, Mechanisms, and Consequences

Inflammation predisposes to the development of cancer and promotes all stages of tumorigenesis. Cancer cells, as well as surrounding stromal and inflammatory cells, engage in well-orchestrated reciprocal interactions to form an inflammatory tumor microenvironment (TME). Cells within the TME are highly plastic, continuously changing their phenotypic and functional characteristics. Here, we review the origins of inflammation in tumors, and the mechanisms whereby inflammation drives tumor initiation, growth, progression, and metastasis. We discuss how tumor-promoting inflammation closely resembles inflammatory processes typically found during development, immunity, maintenance of tissue homeostasis, or tissue repair and illuminate the distinctions between tissue-protective and pro-tumorigenic inflammation, including spatiotemporal considerations. Defining the cornerstone rules of engagement governing molecular and cellular mechanisms of tumor-promoting inflammation will be essential for further development of anti-cancer therapies.

Ovarian Cancer Dissemination-A Cell Biologist's Perspective

Epithelial ovarian cancer (EOC) comprises multiple disease states representing a variety of distinct tumors that, irrespective of tissue of origin, genetic aberrations and pathological features, share common patterns of dissemination to the peritoneal cavity. EOC peritoneal dissemination is a stepwise process that includes the formation of malignant outgrowths that detach and establish widespread peritoneal metastases through adhesion to serosal membranes. The cell biology associated with outgrowth formation, detachment, and de novo adhesion is at the nexus of diverse genetic backgrounds that characterize the disease. Development of treatment for metastatic disease will require detailed characterization of cellular processes involved in each step of EOC peritoneal dissemination. This article offers a review of the literature that relates to the current stage of knowledge about distinct steps of EOC peritoneal dissemination, with emphasis on the cell biology aspects of the process.

Diet, Microbiota, and Colorectal Cancer

The intestinal epithelium is a very dynamic tissue under a high regenerative pressure, which makes it susceptible to malignant transformation. Proper integration of various cell signaling pathways and a balanced cross talk between different cell types composing the organ are required to maintain intestinal homeostasis. Dysregulation of this balance can lead to colorectal cancer (CRC). Here, we review important insights into molecular and cellular mechanisms of CRC. We discuss how perturbation in complex regulatory networks, including the Wnt, Notch, BMP, and Hedgehog pathways; and how variations in inflammatory signaling, nutrients, and microbiota can affect intestinal homeostasis contributing to the malignant transformation of intestinal cells.

Protective Role of Fecal Microbiota Transplantation on Colitis and Colitis-Associated Colon Cancer in Mice Is Associated With Treg Cells

Colitis-associated cancer (CAC) is the most serious outcome of inflammatory bowel disease, which has an alteration of commensal intestinal microbiota. However, the role of intestinal microbiota on CAC progression is not well-understood. Fecal microbiota transplantation (FMT) was used for treating murine azoxymethane–dextran sodium sulfate (AOM-DSS) model of CAC. Composition of gut microbiota during FMT treatment was analyzed. RT-PCR and ELISA were used to detect the inflammatory factors, and immunofluorescence was applied to examine the phospho-nuclear factor (NF)-κB p65/p100 and Ki67-positive cells in the colons. In addition, flow cytometry was performed to analyze the immune cell after FMT treatment. Rehabilitation of the intestinal microbiota by FMT restored both the ratio and diversity of microbiota during CAC progression. Remarkably, a favorable morphometric outcome characterized by decreased tumor load and size was observed in CAC mice with FMT treatment. In addition, an anti-inflammatory function of FMT was demonstrated by decreasing pro-inflammatory factors but increasing anti-inflammatory factors through inhibiting canonical NF-κB activity and cellular proliferation in colons of CAC mice. The expression of CD4⁺CD25⁺Foxp3⁺ regulatory T cells (Tregs) was significantly increased after FMT treatment in CAC mice, but not T helper (Th)1/2/17 cells. Our study aids in the understanding of CAC pathogenesis and reveals a previously unrecognized role for FMT in the treatment of CAC through restoring the intestinal microbiota and inducing regulatory T cells.

Saccharomyces boulardii alleviates ulcerative colitis carcinogenesis in mice by reducing TNF-α and IL-6 levels and functions and by rebalancing intestinal microbiota

BACKGROUND AND AIMS

To explore the inhibition mechanism of Saccharomyces boulardii (S. boulardii) on ulcerative colitis (UC) carcinogenesis.

METHODS

C57BL/6 mice were treated with azoxymethane and dextran sulfate sodium (AOM/DSS) to develop a UC carcinogenesis model. The treatment group was lavaged with S. boulardii (5 × 10⁷ CFU/d) for 12 weeks. The mice were sacrificed and the tumor load in the treatment group was compared with that of a control group. The levels of TNF-α and IL-6 in colon tissue were measured by enzyme-linked immunosorbent assays. The influence of S. boulardii on TNF-α and IL-6 regulation was also investigated using different colon cell lines. Differences in intestinal microbiota in both stool and intestinal mucosa samples were assessed using 16S rDNA sequencing.

RESULTS

S. boulardii treatment reduced AOM/DSS-induced UC carcinogenesis in mice, as indicated by the reduced tumor load and reduced TNF-α and IL-6 levels in vivo, as well its effects on TNF-α and IL-6 activities in vitro. Significant changes in both fecal and mucosal microbiota were observed among the control, the AOM/DSS treated, and AOM/DSS plus S. boulardii treated groups. For fecal microbiota, the AOM/DSS treated group was lower in Lactobacillus, but higher in Oscillibacter and Lachnoclostridium than the control group. After intervention with S. boulardii, the percentage of Bacillus and Lactococcus increased, but Lachnoclostridium, Oscillibacter, Bacteroides, and Pseudomonas decreased. For the intestinal mucosal microbiota, the AOM/DSS treated group was lower in Bifidobacterium and Ruminococcaceae_UCG-014 and higher in Alloprevotella than the control group. After S. boulardii exposure, the percentage contributions of Lachnoclostridium and Lachnospiraceae_NK4A136 increased.

CONCLUSIONS

S. boulardii effectively reduced UC carcinogenesis in an AOM/DSS induced mice model. This positive result can likely be attributed to the reduction of TNF-α and IL-6 levels or the blockade of their function combined with alterations to the intestinal microbiota.

IRW and IQW Reduce Colitis-Associated Cancer Risk by Alleviating DSS-Induced Colonic Inflammation

Background and Objective

Bioactive peptides exert great influence in animals and human health by targeting gastrointestinal tracts. The colitis model of mice was induced by dextran sulfate sodium (DSS). Thirty-two 8-week-old mice weighing 23 g on average were randomly assigned to four groups of 8 each: mice fed basal diet (CON), mice fed basal diet with 5% DSS (DSS), mice fed 0.03% IRW with 5% DSS (IRW-DSS), and mice fed 0.03% IRW with 5% DSS (IQW-DSS). After an adaptation period of 3 days, on day 8, all mice were slaughtered. Serum samples were collected to determine the level of amino acids; colonic tissue was quick-frozen for the determination of gene expression.

Methods

The aim of this study was to assess the ability of two kinds of peptides (IRW and IQW) to repair intestinal inflammatory in the DSS-induced model in accordance with serum amino acids and intestinal inflammatory factors.

Results

The results demonstrated that the addition of IRW and IQW had a mitigating effect on DSS-induced intestinal inflammation. The level of Asp decreased in the serum of mice supplemented with IRW-DSS (P < 0.05), and IQW enhanced the level of Leu, but lowered the level of Ser (P < 0.05). IQW and IRW addition reduced the level of TNF-α and IL-17 (P < 0.05). No other significant effects were observed.

Conclusions

The present study demonstrated that intracolic administration of IRW and IQW might be a novel option for preventing inflammatory bowel disease via regulating the level of serum amino acid and enhancing the intestinal immune defense.

Orally Deliverable Nanotherapeutics for the Synergistic Treatment of Colitis-Associated Colorectal Cancer

Purpose: Colitis-associated colorectal cancer (CAC) poses substantial challenges for effective treatment. Currently, there is a considerable need for the development of orally bioavailable dosage forms that enable the safe and effective delivery of therapeutic drugs to local diseased lesions in the gastrointestinal tract. Experimental Design: In this study, we developed orally deliverable nanotherapeutics for the synergistic treatment of inflammatory bowel diseases (IBDs) and CAC. Water-insoluble curcumin (CUR) and 7-ethyl-10-hydroxycamptothecin (SN38), which served as anti-inflammatory and cytotoxic agents, respectively, were chemically engineered into hydrophilic mucoadhesive chitosan for the generation of chitosan-drug amphiphiles. Results: The resulting amphiphilic constructs formed core-shell nanostructures in aqueous solutions and were orally administered for in vivo therapeutic studies. Using a preclinical CAC mouse model, we showed that the orally delivered nanotherapeutics locally accumulated in inflamed intestinal regions and tumor tissues. Furthermore, the therapeutic synergy of the combined nanotherapeutics in CAC mice was evaluated. Compared with their individual drug forms, combined CUR and SN38 nanoparticles yielded synergistic effects to alleviate intestinal inflammation and protect mice from ulcerative colitis. Notably, the combinatorial therapy demonstrated a remarkable tumor shrinkage with only ~6% of the total tumors exceeding 4 mm in diameter, whereas ~35% of tumors were observed to exceed a diameter of 4 mm in the saline-treated CAC mice. These data suggest a new and reliable approach for improving the treatment of IBD and CAC. Conclusions: Our results showed that bioadhesive chitosan materials can be used to produce colloidal-stable nanotherapeutics that are suitable for oral delivery. Both nanotherapeutics exhibited substantial accumulation in inflamed intestinal regions and tumor tissues and showed good synergy for treating CAC, warranting further clinical translation.

RBPJ inhibits the movability of endometrial carcinoma cells by miR-155/NF-κB/ROS pathway

Background

Recombination signal-binding protein J (RBPJ) is a crucial downstream effector of Notch signaling, which is involved cell proliferation, differentiation, and apoptosis. It plays an important role in tumorigenesis although the further studies and concrete evidence are still needed. Especially for endometrial carcinoma, the functions and mechanism of RBPJ are still elusive.

Methods

The RNA expressions of RBPJ, miR-155, NF-κB, TNF-α and κB-Ras1 were examined by rt-PCR, and their protein levels were determined by Western Blot. Their expressions were inhibited by transient transfection of related siRNAs. Wound healing and transwell invasion assays were performed in ECC003 cells for measuring the migration and invasion ability, respectively. The ROS levels were detected by flow cytometry with H2DCFDA.

Purpose

This study was designed to investigate biological characteristics and molecular pathway of RBPJ in endometrial carcinoma cells, which may provide a potential therapeutic target for the treatments against endometrial carcinoma.

Results

It was shown in our study that the expression levels of RBPJ were significantly downregulated in different endometrial carcinoma cell lines. And a siRNA-mediated reduction of RBPJ enhanced the migration and invasion ability of ECC003 obviously. Besides, the results showed that the reactive oxygen species (ROS) levels increase when inhibiting RBPJ. To investigate the molecular pathway of RBPJ, we examined the expression of nuclear factor-κB (NF-κB), NF-κB inhibitor interacting Ras-like protein 1 (κB-Ras1), tumor necrosis factor-α (TNF-α) and miR-155. The results suggested that the expression of NF-κB and TNF-α significantly was promoted, while κB-Ras1 was inhibited. An upregulated expression was observed with miR-155 as well, which suggested the inhibition of NF-κB signal pathway was mediated by miR-155. Our results of Notch intracellular domain (NICD) knockdown also demonstrated that NICD is required for the inhibition of RBPJ on miR-155. And knockdown of miR-155 could inhibit the mobility of endometrial carcinoma cells.

Conclusion

Our study suggested that RBPJ can inhibit the movability of endometrial carcinoma cells by miR-155/NF-κB/ROS pathway.

Transient receptor potential ankyrin1 channel is endogenously expressed in T cells and is involved in immune functions

Transient receptor potential channel subfamily A member 1 (TRPA1) is a non-selective cationic channel, identified initially as a cold sensory receptor. TRPA1 responds to diverse exogenous and endogenous stimuli associated with pain and inflammation. However, the information on the role of TRPA1 toward T-cell responses remains scanty. In silico data suggest that TRPA1 can play an important role in the T-cell activation process. In this work, we explored the endogenous expression of TRPA1 and its function in T cells. By reverse transcription polymerase chain reaction (RT-PCR), confocal microscopy and flow cytometry, we demonstrated that TRPA1 is endogenously expressed in primary murine splenic T cells as well as in primary human T cells. TRPA1 is primarily located at the cell surface. TRPA1-specific activator namely allyl isothiocyanate (AITC) increases intracellular calcium ion (Ca²⁺) levels while two different inhibitors namely A-967079 as well as HC-030031 reduce intracellular Ca²⁺ levels in T cells; TRPA1 inhibition also reduces TCR-mediated calcium influx. TRPA1 expression was found to be increased during αCD3/αCD28 (TCR) or Concanavalin A (ConA)-driven stimulation in T cells. TRPA1-specific inhibitor treatment prevented induction of cluster of differentiation 25 (CD25), cluster of differentiation 69 (CD69) in ConA/TCR stimulated T cells and secretion of cytokines like tumor necrosis factor (TNF), interferon γ (IFN-γ), and interleukin 2 (IL-2) suggesting that endogenous activity of TRPA1 may be involved in T-cell activation. Collectively these results may have implication in T cell-mediated responses and indicate possible role of TRPA1 in immunological disorders.

Notabi M, El-Houri RB, Pipó-Ollé E, Christensen Arnspang E, Christensen LP. Dietary Polyacetylenic Oxylipins Falcarinol and Falcarindiol Prevent Inflammation and Colorectal Neoplastic Transformation: A Mechanistic and Dose-Response Study in A Rat Model

Falcarinol (FaOH) and falcarindiol (FaDOH) are cytotoxic and anti-inflammatory polyacetylenic oxylipins, which are commonly found in the carrot family (Apiaceae). FaOH and FaDOH have previously demonstrated a chemopreventive effect on precursor lesions of colorectal cancer (CRC) in azoxymethane (AOM)-induced rats. The purpose of the present study was to elucidate possible mechanisms of action for the preventive effect of FaOH and FaDOH on colorectal precancerous lesions and to determine how this effect was dependent on dose. Gene expression studies performed by RT-qPCR of selected cancer biomarkers in tissue from biopsies of neoplastic tissue revealed that FaOH and FaDOH downregulated NF-κβ and its downstream inflammatory markers TNFα, IL-6, and COX-2. The dose-dependent anti-neoplastic effect of FaOH and FaDOH in AOM-induced rats was investigated in groups of 20 rats receiving a standard rat diet (SRD) supplemented with 0.16, 0.48, 1.4, 7 or 35 µg FaOH and FaDOH g⁻¹ feed in the ratio 1:1 and 20 rats were controls receiving only SRD. Analysis of aberrant crypt foci (ACF) showed that the average number of small ACF (<7 crypts) and large ACF (>7 crypts) decreased with increasing dose of FaOH and FaDOH and that this inhibitory effect on early neoplastic formation of ACF was dose-dependent, which was also the case for the total number of macroscopic neoplasms. The CRC protective effects of apiaceous vegetables are mainly due to the inhibitory effect of FaOH and FaDOH on NF-κB and its downstream inflammatory markers, especially COX-2.

Minimal intervening control of biomolecular networks leading to a desired cellular state

A cell phenotype can be represented by an attractor state of the underlying molecular regulatory network, to which other network states eventually converge. Here, the set of states converging to each attractor is called its basin of attraction. A central question is how to drive a particular cell state toward a desired attractor with minimal interventions on the network system. We develop a general control framework of complex Boolean networks to provide an answer to this question by identifying control targets on which one-time temporary perturbation can induce a state transition to the boundary of a desired attractor basin. Examples are shown to illustrate the proposed control framework which is also applicable to other types of complex Boolean networks.

Role of NLRP6 in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory disease of unknown etiology. The symptoms of IBD are prone to recurrent episodes, and there is currently limited treatment and efficacy. Recently, there have been many studies showing that the nucleotide-binding oligomerization domain-like receptor containing the pyrin domain containing protein (NLR family, pyrin domain containing 6, NLRP6) regulates intestinal immunity and microorganisms in inflammatory bowel disease and related tumors. NLRP6 promotes the secretion of interleukin (IL)-18 and antimicrobial peptides, and IL-18 can inhibit the production of IL-22BP, enhance the role of IL-22, and promote the proliferation of epithelial cells through the MyD88 pathway. NLRP6 also regulates the secretion of mucoprotein 2 by goblet cells via Toll-like receptors, clears intestinal bacteria, regulates intestinal immune function, and maintains intestinal flora. Because IBD is associated with a tendency of malignant transformation, and researchers have found that NLRP6 can act on NOTCH and Wnt, activate chemokine ligand 5 and IL-6 signaling, regulate epithelial cell proliferation, and affect the development of IBD-related colorectal cancer. This article reviews the role of NLRP6 in IBD.

The indole compound MA-35 attenuates tumorigenesis in an inflammation-induced colon cancer model

In inflammatory bowel disease, chronic inflammation results in the development of colon cancer known as colitis-associated cancer. This disease is associated with tumor necrosis factor-α (TNF-α) signaling. In addition, intestinal fibrosis is a common clinical complication that is promoted by transforming growth factor β1 (TGF-β₁). In our previous study, MA-35 attenuated renal fibrosis by inhibiting both TNF-α and TGF-β₁ signaling. This study aimed to identify the possible antitumor effects and antifibrotic effects of MA-35 using an AOM/DSS mouse model. MA-35 was orally administered every day for 70 days in the AOM/DSS mouse model. There was no difference in weight loss between the AOM/DSS group and the AOMDSS + MA-35 group, but the disease activity index score and the survival rate were improved by MA-35. MA-35 blocked the anemia and shortening of the colon induced by AOM/DSS. MA-35 reduced the macroscopic formation of tumors in the colon. In the microscopic evaluation, MA-35 reduced inflammation and fibrosis in areas with dysplasia. Furthermore, the TNF-α mRNA level in the colon tended to be reduced, and the interleukin 6, TGF-β₁ and fibronectin 1 mRNA levels in the colon were significantly reduced by MA-35. These results suggested that MA-35 inhibited AOM/DSS-induced carcinogenesis by reducing inflammation and fibrosis.

Hypoxic Regulation of Neutrophils in Cancer

Neutrophils have been well-characterized for their role in the host anti-microbial response. However, it is now appreciated that neutrophils have a critical role in tumorigenesis and tumor progression in the majority of solid tumors. Recent studies have indicated a critical role for hypoxia in regulating neutrophil function in tumors. Furthermore, neutrophil-specific expression of hypoxia-inducible transcription factors may represent a novel therapeutic target for human cancer. In this review, we highlight the function of neutrophils in cancer and the role of the neutrophil hypoxic response in regulating the neoplastic progression of cancer.

Differential responses of epithelial cells from urinary and biliary tract to eggs of Schistosoma haematobium and S. mansoni

Chronic urogenital schistosomiasis can lead to squamous cell carcinoma of the bladder. The International Agency for Research on Cancer classifies the infection with S. haematobium as a group 1 carcinogen, a definitive cause of cancer. By contrast, hepatointestinal schistosomiasis due to the chronic infection with S. mansoni or S. japonicum associated with liver periportal fibrosis, does not apparently lead to malignancy. The effects of culturing human epithelial cells, HCV29, established from normal urothelium, and H69, established from cholangiocytes, in the presence of S. haematobium or S. mansoni eggs were investigated. Cell growth of cells co-cultured with schistosome eggs was monitored in real time, and gene expression analysis of oncogenesis, epithelial to mesenchymal transition and apoptosis pathways was undertaken. Schistosome eggs promoted proliferation of the urothelial cells but inhibited growth of cholangiocytes. In addition, the tumor suppressor P53 pathway was significantly downregulated when exposed to schistosome eggs, and downregulation of estrogen receptor was predicted in urothelial cells exposed only to S. haematobium eggs. Overall, cell proliferative responses were influenced by both the tissue origin of the epithelial cells and the schistosome species.

Extra-Adrenal Glucocorticoid Synthesis in the Intestinal Mucosa: Between Immune Homeostasis and Immune Escape

Glucocorticoids (GCs) are steroid hormones predominantly produced in the adrenal glands in response to physiological cues and stress. Adrenal GCs mediate potent anti-inflammatory and immunosuppressive functions. Accumulating evidence in the past two decades has demonstrated other extra-adrenal organs and tissues capable of synthesizing GCs. This review discusses the role and regulation of GC synthesis in the intestinal epithelium in the regulation of normal immune homeostasis, inflammatory diseases of the intestinal mucosa, and the development of intestinal tumors.

The chemopreventive effect of withaferin A on spontaneous and inflammation-associated colon carcinogenesis models

Chemopreventive effects and associated mechanisms of withaferin A (WA) against intestinal and colon carcinogenesis remain unknown. We investigated the chemopreventive effect of WA on transgenic adenomatous polyposis coli (APCMin/+) mouse and chemically induced azoxymethane/dextran sodium sulfate (AOM/DSS) models of intestinal and colon carcinogenesis. Oral WA administration (4 and 3 mg/kg) inhibited tumor initiation and progression of intestinal polyps formation in APCMin/+ mice and colon carcinogenesis in the AOM/DSS mouse model. WA-administered mice showed a significant reduction in both number [duodenum, 33% (P > 0.05); jejunum, 32% (P < 0.025); ileum, 43% ( P < 0.001); and colon 59% (P < 0.01] and size of polyps in APCMin/+ mice compared with the respective controls. Similarly, tumor multiplicity was significantly reduced (P < 0.05) in the colon of WA-administered AOM/DSS mice. Pathological analysis showed reduced adenomas and tissue inflammation in WA-administered mouse models. Molecular studies suggested that WA inhibited the expression of inflammatory (interluekin-6, tumor necrosis factor-alpha and cyclooxygenase-2), pro-survival (pAKT, Notch1 and NF-κB) markers in APCMin/+ and AOM/DSS models. The results suggest that WA is a potent agent for preventing colon carcinogenesis and further investigation is required to show clinical utility of the agent.

Chemopreventive Effects of Strawberry and Black Raspberry on Colorectal Cancer in Inflammatory Bowel Disease

Colorectal cancer (CRC) remains the third most common cause of cancer-related death in the United States and the fourth globally with a rising incidence. Inflammatory bowel disease (IBD) is a chronic immunologically mediated disease that imposes a significant associated health burden, including the increased risk for colonic dysplasia and CRC. Carcinogenesis has been attributed to chronic inflammation and associated with oxidative stress, genomic instability, and immune effectors as well as the cytokine dysregulation and activation of the nuclear factor kappa B (NFκB) signaling pathway. Current anti-inflammation therapies used for IBD treatment have shown limited effects on CRC chemoprevention, and their long-term toxicity has limited their clinical application. However, natural food-based prevention approaches may offer significant cancer prevention effects with very low toxicity profiles. In particular, in preclinical and clinical pilot studies, strawberry and black raspberry have been widely selected as food-based interventions because of their potent preventive activities. In this review, we summarize the roles of strawberry, black raspberry, and their polyphenol components on CRC chemoprevention in IBD.

Apoptosis of tumor-infiltrating T lymphocytes: a new immune checkpoint mechanism

Immunotherapy based on checkpoint inhibitors is providing substantial clinical benefit, but only to a minority of cancer patients. The current priority is to understand why the majority of patients fail to respond. Besides T-cell dysfunction, T-cell apoptosis was reported in several recent studies as a relevant mechanism of tumoral immune resistance. Several death receptors (Fas, DR3, DR4, DR5, TNFR1) can trigger apoptosis when activated by their respective ligands. In this review, we discuss the immunomodulatory role of the main death receptors and how these are shaping the tumor microenvironment, with a focus on Fas and its ligand. Fas-mediated apoptosis of T cells has long been known as a mechanism allowing the contraction of T-cell responses to prevent immunopathology, a phenomenon known as activation-induced cell death, which is triggered by induction of Fas ligand (FasL) expression on T cells themselves and qualifies as an immune checkpoint mechanism. Recent evidence indicates that other cells in the tumor microenvironment can express FasL and trigger apoptosis of tumor-infiltrating lymphocytes (TIL), including endothelial cells and myeloid-derived suppressor cells. The resulting disappearance of TIL prevents anti-tumor immunity and may in fact contribute to the absence of TIL that is typical of "cold" tumors that fail to respond to immunotherapy. Interfering with the Fas-FasL pathway in the tumor microenvironment has the potential to increase the efficacy of cancer immunotherapy.

Tumour Necrosis Factor Alpha in Intestinal Homeostasis and Gut Related Diseases

The intestinal epithelium constitutes an indispensable single-layered barrier to protect the body from invading pathogens, antigens or toxins. At the same time, beneficial nutrients and water have to be absorbed by the epithelium. To prevent development of intestinal inflammation or tumour formation, intestinal homeostasis has to be tightly controlled and therefore a strict balance between cell death and proliferation has to be maintained. The proinflammatory cytokine tumour necrosis factor alpha (TNFα) was shown to play a striking role for the regulation of this balance in the gut. Depending on the cellular conditions, on the one hand TNFα is able to mediate cell survival by activating NFκB signalling. On the other hand, TNFα might trigger cell death, in particular caspase-dependent apoptosis but also caspase-independent programmed necrosis. By regulating these cell death and survival mechanisms, TNFα exerts a variety of beneficial functions in the intestine. However, TNFα signalling is also supposed to play a critical role for the pathogenesis of inflammatory bowel disease (IBD), infectious diseases, intestinal wound healing and tumour formation. Here we review the literature about the physiological and pathophysiological role of TNFα signalling for the maintenance of intestinal homeostasis and the benefits and difficulties of anti-TNFα treatment during IBD.

Inflammatory responses bridge comorbid cardiac disorder in experimental model of IBD induced by DSS: protective effect of the trigonelline

Pathogenesis of the inflammatory bowel disease (IBD) involves the combination of immunological and inflammatory factors. IBD is associated with several extra-intestinal manifestations. The exact underlying bridge between the probable cardiac diseases in IBD patients is undetermined. Trigonelline is an alkaloid with several therapeutic potential properties. In this study, we aimed to assess the probable underlying mechanisms of this comorbidity as well as protective effect of trigonelline focusing inflammatory response and oxidative state in mouse model of colitis. Dextran sodium sulfate (DSS) was used for induction of colitis in mice. Trigonelline (10, 50 and 100 mg/kg) was administrated via intraperitoneal rout (i.p.) for 14 continuous days. Heart, intestine and serum samples were taken for assessment of total antioxidant capacity, malondialdehyde (MDA), gene expressions of inflammatory markers including tumor necrosis factor alpha (Tnf-α), interleukin 1-beta (Il/1β), toll- like receptor 4 (Tlr4) as well as for evaluation of histopathological alterations. Results demonstrated that trigonelline effectively attenuated the cellular/molecular and histopathological adverse effects of colitis in the intestine and heart tissues. In this regards, we found that trigonelline decreased the MDA level, attenuated the expression of Tnf-α, Il/1β and, Tlr4 as well as modulated the histopathological alterations in the intestine. Furthermore, trigonelline increased the antioxidant capacity in the related experimental groups. We concluded that IBD (colitis) is associated with comorbid cellular/molecular modifications in the heart and for the first time, we found that trigonelline has potential therapeutic effects (at least partially) to attenuate the cardiac manifestations of the colitis.

Effects of 17β-Estradiol on Colonic Permeability and Inflammation in an Azoxymethane/Dextran Sulfate Sodium-Induced Colitis Mouse Model

Background/Aims

Intestinal barrier dysfunction is a hallmark of inflammatory bowel diseases (IBDs) such as ulcerative colitis. This dysfunction is caused by increased permeability and the loss of tight junctions in intestinal epithelial cells. The aim of this study was to investigate whether estradiol treatment reduces colonic permeability, tight junction disruption, and inflammation in an azoxymethane (AOM)/dextran sodium sulfate (DSS) colon cancer mouse model.

Methods

The effects of 17β-estradiol (E2) were evaluated in ICR male mice 4 weeks after AOM/DSS treatment. Histological damage was scored by hematoxylin and eosin staining and the levels of the colonic mucosal cytokine myeloperoxidase (MPO) were assessed by enzyme-linked immunosorbent assay (ELISA). To evaluate the effects of E2 on intestinal permeability, tight junctions, and inflammation, we performed quantitative real-time polymerase chain reaction and Western blot analysis. Furthermore, the expression levels of mucin 2 (MUC2) and mucin 4 (MUC4) were measured as target genes for intestinal permeability, whereas zonula occludens 1 (ZO-1), occludin (OCLN), and claudin 4 (CLDN4) served as target genes for the tight junctions.

Results

The colitis-mediated induced damage score and MPO activity were reduced by E2 treatment (p<0.05). In addition, the mRNA expression levels of intestinal barrier-related molecules (i.e., MUC2, ZO-1, OCLN, and CLDN4) were decreased by AOM/DSS-treatment; furthermore, this inhibition was rescued by E2 supplementation. The mRNA and protein expression of inflammation-related genes (i.e., KLF4, NF-κB, iNOS, and COX-2) was increased by AOM/DSS-treatment and ameliorated by E2.

Conclusions

E2 acts through the estrogen receptor β signaling pathway to elicit anti-inflammatory effects on intestinal barrier by inducing the expression of MUC2 and tight junction molecules and inhibiting pro-inflammatory cytokines.

Cross-Talk Between Antigen Presenting Cells and T Cells Impacts Intestinal Homeostasis, Bacterial Infections, and Tumorigenesis

Innate immunity is maintained in part by antigen presenting cells (APCs) including dendritic cells, macrophages, and B cells. APCs interact with T cells to link innate and adaptive immune responses. By displaying bacterial and tumorigenic antigens on their surface via major histocompatibility complexes, APCs can directly influence the differentiation of T cells. Likewise, T cell activation, differentiation, and effector functions are modulated by APCs utilizing multiple mechanisms. The objective of this review is to describe how APCs interact with and influence the activation of T cells to maintain innate immunity during exposure to microbial infection and malignant cells. How bacteria and cancer cells take advantage of some of these interactions for their own benefit will also be discussed. While this review will cover a broad range of topics, a general focus will be held around pathogens, cancers, and interactions that typically occur within the gastrointestinal tract.

Tributyrin in Inflammation: Does White Adipose Tissue Affect Colorectal Cancer?

Colorectal cancer affects the large intestine, leading to loss of white adipose tissue (WAT) and alterations in adipokine secretion. Lower incidence of colorectal cancer is associated with increased fibre intake. Fructooligosaccharides (FOS) are fibres that increase production of butyrate by the intestinal microbiota. Tributyrin, a prodrug of butyric acid, exerts beneficial anti-inflammatory effects on colorectal cancer. Our aim was to characterise the effects of diets rich in FOS and tributyrin within the context of a colon carcinogenesis model, and characterise possible support of tumorigenesis by WAT. C57/BL6 male mice were divided into four groups: a control group (CT) fed with chow diet and three colon carcinogenesis-induced groups fed either with chow diet (CA), tributyrin-supplemented diet (BUT), or with FOS-supplemented diet. Colon carcinogenesis decreased adipose mass in subcutaneous, epididymal, and retroperitoneal tissues, while also reducing serum glucose and leptin concentrations. However, it did not alter the concentrations of adiponectin, interleukin (IL)-6, IL-10, and tumour necrosis factor alpha (TNF)-α in WAT. Additionally, the supplements did not revert the colon cancer affected parameters. The BUT group exhibited even higher glucose tolerance and levels of IL-6, VEGF, and TNF-α in WAT. To conclude our study, FOS and butyrate supplements were not beneficial. In addition, butyrate worsened adipose tissue inflammation.

Mouse Model of Colitis-Associated Colorectal Cancer (CAC): Isolation and Characterization of Mucosal-Associated Lymphoid Cells

Colorectal cancer (CRC) is the third most common malignancy worldwide presenting high mortality due to low treatment efficacy. Existing evidence indicates that inflammatory bowel disease (IBD) is associated with a higher risk of developing CRC. Many murine models of inflammation-related colon carcinogenesis (CAC) have been developed to study colon carcinogenesis and novel treatments. A commonly used model involves the combination of a single dose of azoxymethane (AOM), together with three cycles of the inflammatory agent dextran sodium sulfate (DSS) (5 days in drinking water followed by a two-week rest). Following this protocol, around 50% of the animals develop CRCs after 45 days and almost 100% of animals after 60 days. During CAC development, immune cells, cytokines, and other immune mediators are involved in both tumorigenesis and the elimination of cancer cells during immunotherapy. Thus, the study of mucosal immune responses (including lamina propria mononuclear cells and intraepithelial lymphocytes) is important to understand the role of the immune system during development and therapy in CRC. Single immune cell suspensions from lamina propria and epithelium can be purified combining selective tissue digestion and Percoll gradient centrifugation. Isolated cells can be characterized using flow cytometry by analyzing surface antigens or intracellular cytokines and cytotoxic mediators or employed for further investigations like comparative studies of mRNA expression, cell-proliferation assay, protein analysis, or even functional cytotoxicity assays. The CAC model is useful to study the involvement of immune cells not only during the carcinogenesis process but, in addition, during the treatment with novel immunotherapy protocols.

Obesity-Induced TNFα and IL-6 Signaling: The Missing Link between Obesity and Inflammation-Driven Liver and Colorectal Cancers

Obesity promotes the development of numerous cancers, such as liver and colorectal cancers, which is at least partly due to obesity-induced, chronic, low-grade inflammation. In particular, the recruitment and activation of immune cell subsets in the white adipose tissue systemically increase proinflammatory cytokines, such as tumor necrosis factor α (TNFα) and interleukin-6 (IL-6). These proinflammatory cytokines not only impair insulin action in metabolic tissues, but also favor cancer development. Here, we review the current state of knowledge on how obesity affects inflammatory TNFα and IL-6 signaling in hepatocellular carcinoma and colorectal cancers.

miR-34a is a microRNA safeguard for Citrobacter-induced inflammatory colon oncogenesis

Inflammation often induces regeneration to repair the tissue damage. However, chronic inflammation can transform temporary hyperplasia into a fertile ground for tumorigenesis. Here, we demonstrate that the microRNA miR-34a acts as a central safeguard to protect the inflammatory stem cell niche and reparative regeneration. Although playing little role in regular homeostasis, miR-34a deficiency leads to colon tumorigenesis after Citrobacter rodentium infection. miR-34a targets both immune and epithelial cells to restrain inflammation-induced stem cell proliferation. miR-34a targets Interleukin six receptor (IL-6R) and Interleukin 23 receptor (IL-23R) to suppress T helper 17 (Th17) cell differentiation and expansion, targets chemokine CCL22 to hinder Th17 cell recruitment to the colon epithelium, and targets an orphan receptor Interleukin 17 receptor D (IL-17RD) to inhibit IL-17-induced stem cell proliferation. Our study highlights the importance of microRNAs in protecting the stem cell niche during inflammation despite their lack of function in regular tissue homeostasis.

Screening and surveillance methods for dysplasia in inflammatory bowel disease patients: Where do we stand?

Patients with long-standing ulcerative colitis (UC) and extensive Crohn’s colitis (CC) are at increased risk for dysplasia and colorectal cancer (CRC). Several studies have shown that UC extending proximal to the rectum, CC involving at least 1/3 of the colon, co-existence of primary sclerosing cholangitis, undetermined or unclassified colitis, family history of CRC and young age at diagnosis appear to be independent risk factors for inflammatory bowel disease (IBD) - related CRC. Therefore, screening and surveillance for CRC in IBD patients is highly recommended by international and national guidelines, whilst colonoscopy remains the unequivocal tool in order to detect potentially resectable dysplastic lesions or CRC at an early stage. Although the importance of screening and surveillance is widely proven, there is a controversy regarding the time of the first colonoscopy and the criteria of who should undergo surveillance. In addition, there are different recommendations among scientific societies concerning which endoscopic method is more efficient to detect dysplasia early, as well as the terminology for reporting visible lesions and the management of those lesions. This article concisely presents the main endoscopic methods and techniques performed for detecting dysplasia and CRC surveillance in patients with IBD focusing on their evidence-based accuracy and efficiency, as well as their cost-effectiveness. Finally, newer methods are mentioned, highlighting their applicability in daily endoscopic practice.

Anticancer Therapy-Induced Atrial Fibrillation: Electrophysiology and Related Mechanisms

Some well-established immunotherapy, radiotherapy, postoperation, anticancer drugs such as anthracyclines, antimetabolites, human epidermal growth factor receptor 2 blockers, tyrosine kinase inhibitors, alkylating agents, checkpoint inhibitors, and angiogenesis inhibitors, are significantly linked to cardiotoxicity. Cardiotoxicity is a common complication of several cancer treatments. Some studies observed complications of cardiac arrhythmia associated with the treatment of cancer, including atrial fibrillation (AF), supraventricular arrhythmias, and cardiac repolarization abnormalities. AF increases the risk of cardiovascular morbidity and mortality; it is associated with an almost doubled risk of mortality and a nearly 5-fold increase in the risk of stroke. The occurrence of AF is also usually researched in patients with advanced cancer and those undergoing active cancer treatments. During cancer treatments, the incidence rate of AF affects the prognosis of tumor treatment and challenges the treatment strategy. The present article is mainly focused on the cardiotoxicity of cancer treatments. In our review, we discuss these anticancer therapies and how they induce AF and consequently provide information on the precaution of AF during cancer treatment.

Dietary Supplementation of Selenoneine-Containing Tuna Dark Muscle Extract Effectively Reduces Pathology of Experimental Colorectal Cancers in Mice

Selenoneine is an ergothioneine analog with greater antioxidant activity and is the major form of organic selenium in the blood, muscles, and other tissues of tuna. The aim of this study was to determine whether a selenoneine-rich diet exerts antioxidant activities that can prevent carcinogenesis in two types of colorectal cancer model in mice. We administrated selenoneine-containing tuna dark muscle extract (STDME) to mice for one week and used azoxymethane (AOM) and dextran sodium sulfate (DSS) for inducing colorectal carcinogenesis. Next, we examined the incidence of macroscopic polyps and performed functional analysis of immune cells from the spleen. In the AOM/DSS-induced colitis-associated cancer (CAC) model, the oral administration of STDME significantly decreased tumor incidence and inhibited the accumulation of myeloid-derived suppressor cells (MDSCs) while also inhibiting the downregulation of interferon-γ (IFN-γ) production during carcinogenesis. These results suggest that dietary STDME may be an effective agent for reducing colorectal tumor progression.

Ornithine Decarboxylase in Macrophages Exacerbates Colitis and Promotes Colitis-Associated Colon Carcinogenesis by Impairing M1 Immune Responses

Ornithine decarboxylase (ODC) is the rate-limiting enzyme for polyamine biosynthesis and restricts M1 macrophage activation in gastrointestinal (GI) infections. However, the role of macrophage ODC in colonic epithelial-driven inflammation is unknown. Here, we investigate cell-specific effects of ODC in colitis and colitis-associated carcinogenesis (CAC). Human colonic macrophages expressed increased ODC levels in active ulcerative colitis and Crohn's disease, colitis-associated dysplasia, and CAC. Mice lacking Odc in myeloid cells (OdcΔmye mice) that were treated with dextran sulfate sodium (DSS) exhibited improved survival, body weight, and colon length and reduced histologic injury versus control mice. In contrast, GI epithelial-specific Odc knockout had no effect on clinical parameters. Despite reduced histologic damage, colitis tissues of OdcΔmye mice had increased levels of multiple proinflammatory cytokines and chemokines and enhanced expression of M1, but not M2 markers. In the azoxymethane-DSS model of CAC, OdcΔmye mice had reduced tumor number, burden, and high-grade dysplasia. Tumors from OdcΔmye mice had increased M1, but not M2 macrophages. Increased levels of histone 3, lysine 9 acetylation, a marker of open chromatin, were manifest in tumor macrophages of OdcΔmye mice, consistent with our findings that macrophage ODC affects histone modifications that upregulate M1 gene transcription during GI infections. These findings support the concept that macrophage ODC augments epithelial injury-associated colitis and CAC by impairing the M1 responses that stimulate epithelial repair, antimicrobial defense, and antitumoral immunity. They also suggest that macrophage ODC is an important target for colon cancer chemoprevention.Significance: Ornithine decarboxylase contributes to the pathogenesis of colitis and associated carcinogenesis by impairing M1 macrophage responses needed for antitumoral immunity; targeting ODC in macrophages may represent a new strategy for chemoprevention. Cancer Res; 78(15); 4303-15. ©2018 AACR.

Cancer Cell-Intrinsic PD-1 and Implications in Combinatorial Immunotherapy

Programmed death 1 (PD-1) and its two natural ligands PD-L1 and PD-L2 are responsible for delivering inhibitory signals that regulate the balance between T cell activation, tolerance, and immunopathology. In previous studies, PD-1 was found only expressed on the surface of immune cells, such as T cells and B cells while PD-1’s ligands PD-L1 and PD-L2 were found expressed in some tumor cells. However, recent studies revealed intrinsic expression of PD-1 in melanoma and some other cancers. In melanoma cells, PD-1 can be activated by its ligand PD-L1 expressed by tumor cells, modulating downstream mammalian target of rapamycin signaling and promoting tumor growth independent of adaptive immunity. In addition to melanoma, PD-1 was also detected in liver cancer cells as well as in non-small lung cancer cells. Unlike its oncogenic functions in melanoma and hepatic carcinoma cells, PD-1 seemed to play a distinct role in lung cancer, as blockade of PD-1 instead promoted tumor cells proliferation. Tumor-intrinsic PD-1 expression seems to be widespread in many tumor types, according to our reanalysis on cancer transcriptomic and proteomic data. The multifaceted roles of PD-1 in tumor cells beyond immune checkpoint signaling may explain the differential therapeutic effects of anti-PD-1 and anti-PD-L1 drugs and provide crucial information when developing combinatorial approaches to enhance antitumor immunity.

ST2/IL-33 signaling promotes malignant development of experimental squamous cell carcinoma by decreasing NK cells cytotoxicity and modulating the intratumoral cell infiltrate

Squamous cell carcinoma (SCC) is the second most common form of skin cancer and the mechanism(s) involved in the progression of this tumor are unknown. Increases in the expression of IL-33/ST2 axis components have been demonstrated to contribute to neoplastic transformation in several tumor models and interleukin-33 is correlated with poor prognosis of patients with squamous cell carcinoma of the tongue. Based on these observations, we sought to determine the role of the IL-33/ST2 pathway during the development of SCC. Our findings show that ST2-deficiency led to a marked decrease in the severity of skin lesions, suggesting that ST2 signaling contributed to tumor development. An analysis of tumor lesions in wild-type and ST2KO mice revealed that a lack of ST2 was associated with specific and significant reductions in the numbers of CD4⁺ T cells, CD8⁺ T cells, dendritic cells, and macrophages. In addition, NK cells that were isolated from ST2KO mice exhibited higher cytotoxic activity than cells isolated from wild-type mice. Notably, ST2 deficiency resulted in lower IFN-γ, TNF-α, IL-10, and IL-17 production in tumor samples. Our findings indicate that the IL-33/ST2 pathway contributes to the development of SCC by affecting leukocyte migration to tumor microenvironment and impairing NK cytotoxic activity.

TRAF3IP2, a novel therapeutic target in glioblastoma multiforme

Glioblastoma multiforme (glioblastoma) remains one of the deadliest cancers. Pro-inflammatory and pro-tumorigenic mediators present in tumor microenvironment (TME) facilitate communication between tumor cells and adjacent non-malignant cells, resulting in glioblastoma growth. Since a majority of these mediators are products of NF-κB- and/or AP-1-responsive genes, and as TRAF3 Interacting Protein 2 (TRAF3IP2) is an upstream regulator of both transcription factors, we hypothesized that targeting TRAF3IP2 blunts tumor growth by inhibiting NF-κB and pro-inflammatory/pro-tumorigenic mediators. Our in vitro data demonstrate that similar to primary glioblastoma tumor tissues, malignant glioblastoma cell lines (U87 and U118) express high levels of TRAF3IP2. Silencing TRAF3IP2 expression inhibits basal and inducible NF-κB activation, induction of pro-inflammatory mediators, clusters of genes involved in cell cycle progression and angiogenesis, and formation of spheroids. Additionally, silencing TRAF3IP2 significantly increases apoptosis. In vivo studies indicate TRAF3IP2-silenced U87 cells formed smaller tumors. Additionally, treating existing tumors formed by wild type U87 cells with lentiviral TRAF3IP2 shRNA markedly regresses their size. Analysis of residual tumors revealed reduced expression of pro-inflammatory/pro-tumorigenic/pro-angiogenic mediators and kinesins. In contrast, the expression of IL-10, an anti-inflammatory cytokine, was increased. Together, these novel data indicate that TRAF3IP2 is a master regulator of malignant signaling in glioblastoma, and its targeting modulates the TME and inhibits tumor growth by suppressing the expression of mediators involved in inflammation, angiogenesis, growth, and malignant transformation. Our data identify TRAF3IP2 as a potential therapeutic target in glioblastoma growth and dissemination.

Anticancer potential, molecular mechanisms and toxicity of Euterpe oleracea extract (açaí): A systematic review

Cancer is an increasingly frequent malignancy worldwide, and despite the advances in drug development, it is still necessary to develop new plant-derived medicines. Euterpe oleracea (açaí) is abundant in South and Central America and has health benefits due to its high levels of phytochemicals, including lignans and polyphenols. The aim of this review was to systematically describe the safety and antitumor effects of açaí in preclinical models using rodents to provide a more comprehensive assessment of açaí for both therapeutic uses and the development of future clinical studies in cancer. Eligible studies were identified using four international databases (PubMed, Medline, Lilacs and SciELO) from their inception date through December 2017. The included studies were analyzed with methodological rigor (QATRS) to enable better quality control for these experimental studies. Sixty publications were identified in the databases, but only 9 articles were eligible: 6 evaluated the pharmacological effects of açaí in animal models of cancer (1 model each of esophageal cancer, urothelial cancer, melanoma and Walker-256 tumor and 2 models of colon cancer), and 3 were toxicological assays using preclinical models with rodents. Overall, 747 animals were analyzed. On a QATRS score scale of 0-20, the quality of the studies ranged from 16 to 20 points. Pulp was the main fraction of açaí administered, and an oral administration route was most common. The açaí dosage administered by gavage ranged from 30 mg/kg to 40,000 mg/kg, and açaí fed in the diet accounted for 2.5% to 5% of the diet. The anticarcinogenic and chemopreventive activities of açaí were observed in all experimental models of cancer and reduced the incidence, tumor cell proliferation, multiplicity and size of the tumors due to the antiinflammatory, antiproliferative and proapoptotic properties of açaí. No genotoxic effects were observed after açaí administration. The results of this review suggest that açaí is safe and can be used as a chemoprotective agent against cancer development. Açaí therapy may be a novel strategy for treating cancer.

Bone marrow-derived CXCR4-overexpressing MSCs display increased homing to intestine and ameliorate colitis-associated tumorigenesis in mice

Background and Objective

Increasing interest has developed in the therapeutic potential of bone marrow-derived mesenchymal stem cells (MSCs) for the treatment of inflammatory bowel disease (IBD) and IBD-induced cancer. However, whether MSCs have the ability to suppress or promote tumor development remains controversial. The stromal cell-derived factor 1 (SDF-1)/C-X-C chemokine receptor type 4 (CXCR4) axis is well known to play a critical role in the homing of MSCs. In this study, we aimed to evaluate the role of CXCR4-overexpressing MSCs on the tumorigenesis of IBD.

Methods

MSCs were transduced with lentiviral vector carrying either CXCR4 or green fluorescent protein (GFP). Chemotaxis and invasion assays were used to detect CXCR4 expression. A mouse model of colitis-associated tumorigenesis was established using azoxymethane and dextran sulfate sodium (DSS). The mice were divided into three groups and then injected with phosphate buffer saline (PBS), MSC-GFP or MSC-CXCR4.

Results

Compared with the mice injected with MSC-GFP, the mice injected with MSC-CXCR4 showed relieved weight loss, longer colons, lower tumor numbers and decreased tumor load; expression of pro-inflammatory cytokines decreased, and signal transducer and activator of transcription 3 (STAT3) phosphorylation level in colon tissue was down-regulated.

Conclusion

CXCR4-overexpressing MSCs exhibited effective anti-tumor function, which may be associated with enhanced homing to inflamed intestinal tissues.

Identification of Synergistic Interaction Between Cannabis-Derived Compounds for Cytotoxic Activity in Colorectal Cancer Cell Lines and Colon Polyps That Induces Apoptosis-Related Cell Death and Distinct Gene Expression

Introduction: Colorectal cancer remains the third most common cancer diagnosis and fourth leading cause of cancer-related mortality worldwide. Purified cannabinoids have been reported to prevent proliferation, metastasis, and induce apoptosis in a variety of cancer cell types. However, the active compounds from Cannabis sativa flowers and their interactions remain elusive.

Research Aim: This study was aimed to specify the cytotoxic effect of C. sativa-derived extracts on colon cancer cells and adenomatous polyps by identification of active compound(s) and characterization of their interaction.

Materials and Methods: Ethanol extracts of C. sativa were analyzed by high-performance liquid chromatography and gas chromatograph/mass spectrometry and their cytotoxic activity was determined using alamarBlue-based assay (Resazurin) and tetrazolium dye-based assay (XTT) on cancer and normal colon cell lines and on dysplastic adenomatous polyp cells. Annexin V Assay and fluorescence-activated cell sorting (FACS) were used to determine apoptosis and cell cycle, and RNA sequencing was used to determine gene expression.

Results: The unheated cannabis extracts (C2F), fraction 7 (F7), and fraction 3 (F3) had cytotoxic activity on colon cancer cells, but reduced activity on normal colon cell lines. Moreover, synergistic interaction was found between F7 and F3 and the latter contains mainly cannabigerolic acid. The F7 and F7+F3 cytotoxic activity involved cell apoptosis and cell cycle arrest in S or G0/G1 phases, respectively. RNA profiling identified 2283 differentially expressed genes in F7+F3 treatment, among them genes related to the Wnt signaling pathway and apoptosis-related genes. Moreover, F7, F3, and F7+F3 treatments induced cell death of polyp cells.

Conclusions:C. sativa compounds interact synergistically for cytotoxic activity against colon cancer cells and induce cell cycle arrest, apoptotic cell death, and distinct gene expression. F3, F7, and F7+F3 are also active on adenomatous polyps, suggesting possible future therapeutic value.

Relationship Between Tumor Necrosis Factor-α rs361525 Polymorphism and Gastric Cancer Risk: A Meta-Analysis

Tumor necrosis factor (TNF)-α, a major part in inflammatory, infectious and tumor processes, and is pivotal at the early stages of gastric cancer. Relationship between its risk and TNF-α rs361525 polymorphism has been demonstrated, but remains conflicting and controversial. Therefore, a meta-analysis was conducted to more precisely estimate this relationship. PubMed, Web of Science, EMBASE and CNKI were comprehensively searched to find out relevant articles through October 5, 2017. The strength of the relationship was assessed using pooled odds ratios and 95% confidence intervals. Totally 20 articles were included involving 4,084 cases and 7,010 controls. No significant relationship between TNF-α rs361525 polymorphism and increased GC risk was found in the whole populations. Subgroup analyses uncovered TNF-α rs361525 polymorphism intensified the risk of GC among Asians under five models, but decreased the risk of GC among Caucasiansin the allelic and dominant models. Subgroup analysis by genotyping methods revealed increased risk for other methods. In conclusion, this meta-analysis suggests TNF-α rs361525 polymorphism is related to the risk of GC, especially for Asians.