Intestinal inflammation and cancer

The attenuating effects of synbiotic containing Cetobacterium somerae and Astragalus polysaccharide against trichlorfon-induced hepatotoxicity in crucian carp (Carassius carassius)

This study aimed to investigate the hepatotoxic effects of trichlorfon on crucian carp (Carassius carassius) and the attenuating effects of a synbiotic combination of Cetobacterium somerae and Astragalus polysaccharide on hepatotoxicity. Results showed that trichlorfon did indeed induce hepatotoxicity in crucian carp and the synbiotic reversed this hepatotoxicity caused by trichlorfon. The synbiotic increased TC, TG, LDL-C, ALT and AST levels and decreased serum HDL-C levels caused by trichlorfon. H&E and Oil Red O staining demonstrated that the synbiotic ameliorated liver damage and abnormal lipid accumulation. The activity of antioxidant enzymes (T-SOD, CAT, GSH-Px) in the liver was also enhanced by the administration of the synbiotic. The supplementation of the synbiotic also increased the level of short-chain fatty acids in the intestine. In addition, the synbiotic balanced the gut microbial composition, leading to a reduction in the abundance of potentially pathogenic bacteria and an increase in the abundance of bacteria producing short-chain fatty acids. In conclusion, these findings indicate that trichlorfon can induce hepatotoxicity in crucian carp, whereas synbiotics can regulate gut microbiota, promote the growth of beneficial bacteria and increase the production of SCFAs, and alleviate trichlorfon-induced liver injury.

Archaea influence composition of endoscopically visible ileocolonic biofilms

The gut microbiota has been implicated as a driver of irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD). Recently we described, mucosal biofilms, signifying alterations in microbiota composition and bile acid (BA) metabolism in IBS and ulcerative colitis (UC). Luminal oxygen concentration is a key factor in the gastrointestinal (GI) ecosystem and might be increased in IBS and UC. Here we analyzed the role of archaea as a marker for hypoxia in mucosal biofilms and GI homeostasis. The effects of archaea on microbiome composition and metabolites were analyzed via amplicon sequencing and untargeted metabolomics in 154 stool samples of IBS-, UC-patients and controls. Mucosal biofilms were collected in a subset of patients and examined for their bacterial, fungal and archaeal composition. Absence of archaea, specifically Methanobrevibacter, correlated with disrupted GI homeostasis including decreased microbial diversity, overgrowth of facultative anaerobes and conjugated secondary BA. IBS-D/-M was associated with absence of archaea. Presence of Methanobrevibacter correlated with Oscillospiraceae and epithelial short chain fatty acid metabolism and decreased levels of Ruminococcus gnavus. Absence of fecal Methanobrevibacter may indicate a less hypoxic GI environment, reduced fatty acid oxidation, overgrowth of facultative anaerobes and disrupted BA deconjugation. Archaea and Ruminococcus gnavus could distinguish distinct subtypes of mucosal biofilms. Further research on the connection between archaea, mucosal biofilms and small intestinal bacterial overgrowth should be performed.

Interval Colorectal Cancer in Inflammatory Bowel Disease: A Review

Inflammatory bowel disease (IBD) increases the risk of dysplasia and colorectal cancer (CRC). Moreover, colitis-associated CRC is responsible for a disproportionate number of CRC-related mortality. For this reason, societies recommend screening and surveillance colonoscopy as the standard of care for patients with ulcerative colitis and Crohn's colitis. Nonetheless, interval cancer defined as CRC detected within the appropriate surveillance interval might still occur despite following guideline recommendations. Even though there is limited data on risk factors associated with interval CRC in IBD, patient and disease-associated factors and technical aspects of the surveillance might play a role. This review aims to provide information on the epidemiology of interval CRC in IBD, the factors that might be associated with its occurrence, and the challenges of CRC screening and dysplasia management in patients with IBD.

Focal Cancer in Colitis

Colorectal cancer (CRC) is a known complication of inflammatory bowel disease (IBD). Widely accepted guidelines recommend that patients with ulcerative colitis diagnosed with CRC undergo total proctocolectomy with or without ileal pouch-anal anastomosis, and that patients with Crohn's disease and CRC undergo either total colectomy or proctocolectomy. These approaches are ideal for preventing synchronous and metachronous cancer, minimizing risk of refractory colitis requiring reoperation, and is the appropriate treatment for the vast majority of patients with IBD who are diagnosed with CRC and require surgical intervention. Segmental colectomy, however, may be considered in select patients with IBD and CRC, specifically in elderly patients with short disease duration, in patients with mild colitis identified preoperatively, in patients with high operative risk and prohibitive comorbidities, and in patients whose CRC appears to be sporadic as opposed to colitis-associated. Patients undergoing segmental resection must be closely surveilled postoperatively for dysplasia, recurrent cancer, and refractory colitis.

Neutrophil-only Histological Assessment of Ulcerative Colitis Correlates with Endoscopic Activity and Predicts Long-term Outcomes in a Multicentre Study

BACKGROUNDS AND AIMS

Absence of neutrophils is the minimum standard to consider histological remission of ulcerative colitis [UC]. The PICaSSO Histological Remission Index [PHRI] is a new simple index for UC, based only on the detection of neutrophils. We evaluate PHRI's correlation with endoscopy and its prognostic value compared with other established indices.

METHODS

Consecutive patients with UC underwent colonoscopy at two referral centres [Birmingham, UK, and Milan, Italy,] and were followed up for 2 years. Correlation between histology (PHRI, Nancy [NHI], and Robarts [RHI] indexes) and endoscopy (Mayo Endoscopic Score [MES], Ulcerative Colitis Endoscopic Index of Severity [UCEIS], and PICaSSO index) was calculated as Spearman coefficients. Diagnostic performance of endoscopy was assessed with receiver operating characteristic [ROC] curves and outcome stratification with Kaplan-Meier curves.

RESULTS

A total of 192 patients with UC was enrolled, representing all grades of endoscopic severity. Correlation between histology and endoscopy did not differ significantly when using PHRI instead of NHI or RHI. In particular, PHRI's correlation with MES, UCEIS, and PICaSSO was 0.745, 0.718, and 0.694, respectively. Endoscopically-assessed remission reflected the absence of neutrophils [PHRI = 0] with areas under the ROC curve of 0.905, 0.906, and 0.877 for MES, UCEIS, and PICaSSO, respectively. The hazard ratio for disease flare between patients in histological activity/remission was statistically similar [p >0.05] across indexes [2.752, 2.706, and 2.871 for RHI, NHI, and PHRI, respectively].

CONCLUSION

PHRI correlates with endoscopy and stratifies risk of relapse similarly to RHI and NHI. Neutrophil-only assessment of UC is a simple yet viable alternative to established histological scores.

Gut dysbiosis: Ecological causes and causative effects on human disease

The gut microbiota plays a role in many human diseases, but high-throughput sequence analysis does not provide a straightforward path for defining healthy microbial communities. Therefore, understanding mechanisms that drive compositional changes during disease (gut dysbiosis) continues to be a central goal in microbiome research. Insights from the microbial pathogenesis field show that an ecological cause for gut dysbiosis is an increased availability of host-derived respiratory electron acceptors, which are dominant drivers of microbial community composition. Similar changes in the host environment also drive gut dysbiosis in several chronic human illnesses, and a better understanding of the underlying mechanisms informs approaches to causatively link compositional changes in the gut microbiota to an exacerbation of symptoms. The emerging picture suggests that homeostasis is maintained by host functions that control the availability of resources governing microbial growth. Defining dysbiosis as a weakening of these host functions directs attention to the underlying cause and identifies potential targets for therapeutic intervention.

Pro-inflammatory Cytokines Promote the Occurrence and Development of Colitis-associated Colorectal Cancer by Inhibiting miR-615-5p

BACKGROUND

Patients with ulcerative colitis (UC) may be prone to colitis-associated colorectal cancer (CAC), but there is still a poor understanding of the underlying mechanism so far. This study intended to clarify the role of pro-inflammatory cytokines and miR-615-5p in this process.

METHODS

This experiment first detected miR-615-5p expressions in paraffin-embedded sections of colonic tissues from patients with UC and CAC. Then, we investigated the mechanism through which pro-inflammatory cytokines affected miR-615-5p. Furthermore, in vivo and in vitro tests were performed to identify how miR-615-5p affected colorectal cancer (CRC). Dual-luciferase reporter assay was then employed to identify the targeting relationship between miR-615-5p and stanniocalcin-1 (STC1).

RESULTS

The miR-615-5p was lowly expressed in both cancerous and noncancerous colonic tissues of patients with CAC. Pro-inflammatory cytokines downregulated miR-615-5p expression. Overexpression of miR-615-5p reduced the proliferation and migration of CRC cells and had a certain therapeutic effect on in human CRC xenograft mice. Stanniocalcin-1 was identified to be a target gene of miR-615-5p and was involved in the effect of miR-615-5p on CRC.

CONCLUSIONS

During the progression from UC to CAC, pro-inflammatory cytokines downregulate miR-615-5p, which may induce the upregulation of STC1, and promote the occurrence and development of tumors. These findings offer new insights into the mechanism of CAC and may indicate novel tumor markers or therapeutic targets.

miR-195-5p as Regulator of γ-Catenin and Desmosome Junctions in Colorectal Cancer

Desmosomes play a key role in the regulation of cell adhesion and signaling. Dysregulation of the desmosome complex is associated with the loss of epithelial cell polarity and disorganized tissue architecture typical of colorectal cancer (CRC). The aim of this study was to investigate and characterize the effect of miR-195-5p on desmosomal junction regulation in CRC. In detail, we proposed to investigate the deregulation of miR-195-5p and JUP, a gene target that encodes a desmosome component in CRC patients. JUP closely interacts with desmosomal cadherins, and downstream, it regulates several intracellular transduction factors. We restored the miR-195-5p levels by transient transfection in colonic epithelial cells to examine the effects of miR-195-5p on JUP mRNA and protein expression. The JUP regulation by miR-195-5p, in turn, determined a modulation of desmosome cadherins (Desmoglein 2 and Desmocollin 2). Furthermore, we focused on whether the miR-195-5p gain of function was also able to modulate the expression of key components of Wnt signaling, such as NLK, LEF1 and Cyclin D1. In conclusion, we have identified a novel mechanism controlled by miR-195-5p in the regulation of adhesive junctions, suggesting its potential clinical relevance for future miRNA-based therapy in CRC.

Retinoid X Receptor agonists as selective modulators of the immune system for the treatment of cancer

Upon heterodimerizing with other nuclear receptors, retinoid X receptors (RXR) act as ligand-dependent transcription factors, regulating transcription of critical signaling pathways that impact numerous hallmarks of cancer. By controlling both inflammation and immune responses, ligands that activate RXR can modulate the tumor microenvironment. Several small molecule agonists of these essential receptors have been synthesized. Historically, RXR agonists were tested for inhibition of growth in cancer cells, but more recent drug discovery programs screen new molecules for inhibition of inflammation or activation of immune cells. Bexarotene is the first successful example of an effective therapeutic that molecularly targets RXR; this drug was approved to treat cutaneous T cell lymphoma and is still used as a standard of care treatment for this disease. No additional RXR agonists have yet achieved FDA approval, but several promising novel compounds are being developed. In this review, we provide an overview of the multiple mechanisms by which RXR signaling regulates inflammation and tumor immunity. We also discuss the potential of RXR-dependent immune cell modulation for the treatment or prevention of cancer and concomitant challenges and opportunities.

Bacteroides acidifaciens and its derived extracellular vesicles improve DSS-induced colitis

Introduction

"Probiotic therapy" to regulate gut microbiota and intervene in intestinal diseases such as inflammatory bowel disease (IBD) has become a research hotspot. Bacteroides acidifaciens, as a new generation of probiotics, has shown beneficial effects on various diseases.

Methods

In this study, we utilized a mouse colitis model induced by dextran sodium sulfate (DSS) to investigate how B. acidifaciens positively affects IBD. We evaluated the effects ofB. acidifaciens, fecal microbiota transplantation, and bacterial extracellular vesicles (EVs) on DSS-induced colitis in mice. We monitored the phenotype of mouse colitis, detected serum inflammatory factors using ELISA, evaluated intestinal mucosal barrier function using Western blotting and tissue staining, evaluated gut microbiota using 16S rRNA sequencing, and analyzed differences in EVs protein composition derived from B. acidifaciens using proteomics to explore how B. acidifaciens has a positive impact on mouse colitis.

Results

We confirmed that B. acidifaciens has a protective effect on colitis, including alleviating the colitis phenotype, reducing inflammatory response, and improving intestinal barrier function, accompanied by an increase in the relative abundance of B. acidifaciens and Ruminococcus callidus but a decrease in the relative abundance of B. fragilis. Further fecal bacterial transplantation or fecal filtrate transplantation confirmed the protective effect of eosinophil-regulated gut microbiota and metabolites on DSS-induced colitis. Finally, we validated that EVs derived from B. acidifaciens contain rich functional proteins that can contribute to the relief of colitis.

Conclusion

Therefore, B. acidifaciens and its derived EVs can alleviate DSS-induced colitis by reducing mucosal damage to colon tissue, reducing inflammatory response, promoting mucosal barrier repair, restoring gut microbiota diversity, and restoring gut microbiota balance in mice. The results of this study provide a theoretical basis for the preclinical application of the new generation of probiotics.

NF-κB downstream miR-1262 disturbs colon cancer cell malignant behaviors by targeting FGFR1

Despite substantial advancements in screening, surgery, and chemotherapy, colorectal cancer remains the second most lethal form of the disease. Nuclear factor kappa B (NF-κB) signaling is a critical driver facilitating the malignant transformation of chronic inflammatory bowel diseases. In this study, deregulated miRNAs that could play a role in colon cancer are analyzed and investigated for specific functions in vitro using cancer cells and in vivo using a subcutaneous xenograft model. miRNA downstream targets are analyzed, and predicted binding and regulation are verified. miR-1262, an antitumor miRNA, is downregulated in colon cancer tissue samples and cell lines. miR-1262 overexpression suppresses colon cancer malignant behaviors in vitro and tumor development and metastasis in a subcutaneous xenograft model and a lung metastasis mouse model in vivo. miR-1262 directly targets fibroblast growth factor receptor 1 (FGFR1) and inhibits FGFR1 expression. FGFR1 overexpression shows oncogenic functions through the regulation of cancer cell proliferation, invasion, and migration; when cotransfected, lv-FGFR1 partially attenuates the antitumor effects of agomir-1262. NF-κB binds to the miR-1262 promoter region and inhibits transcription activity. The NF-κB inhibitor CAPE exerts antitumor effects; miR-1262 inhibition partially reverses CAPE effects on colon cancer cells. Conclusively, miR-1262 serves as an antitumor miRNA in colon cancer by targeting FGFR1. The NF-κB/miR-1262/FGFR1 axis modulates colon cancer cell phenotypes, including proliferation, invasion, and migration.

Appropriate leucine-rich α-2 glycoprotein cut-off value for Japanese patients with ulcerative colitis

BACKGROUND

It has been suggested that serum leucine-rich α-2 glycoprotein (LRG) could be a novel monitoring biomarker for the assessment of disease activity in inflammatory bowel disease. In particular, the relationship between LRG levels and the endoscopically assessed activity of ulcerative colitis (UC) has become a matter of interest.

AIM

To clarify appropriate LRG cut-off values for the prediction of endoscopic and histologic remission in Japanese patients with UC.

METHODS

This was a cross-sectional, single-center, observational study of Japanese patients with UC. Among 213 patients with UC, in whom LRG was measured from September 2020 to February 2022, we recruited 30 patients for whom a total colonoscopy and measurements of LRG and C-reactive protein (CRP) were performed on the same day. We retrospectively analyzed correlations between the LRG and CRP levels and endoscopic indices, including the Mayo endoscopic subscore and UC endoscopic index of severity.

RESULTS

Correlations between the LRG values and the Mayo endoscopic subscore or UC endoscopic index of severity were significant (r = 0.754, P < 0.0001; r = 0.778, P < 0.0001, respectively). There were also significant correlations between CRP levels and Mayo endoscopic subscore or UC endoscopic index of severity (r = 0.599, P = 0.0005; r = 0.563, P = 0.0012, respectively), although the correlation coefficients were higher for LRG. The LRG cut-off value for predicting endoscopic remission was 13.4 μg/mL for a Mayo endoscopic subscore of 0 [area under the curve (AUC): 0.871; 95% confidence interval (CI): 0.744–0.998], and 13.4 μg/mL for an UC endoscopic index of severity of 0 or 1 (AUC: 0.904; 95%CI: 0.792–1.000).

CONCLUSION

LRG may be a surrogate marker for endoscopic activity in UC, with a cut-off value of around 13.4 μg/mL for endoscopically inactive disease.

The Prokineticin System in Inflammatory Bowel Diseases: A Clinical and Preclinical Overview

Inflammatory bowel disease (IBD) includes Crohn's disease (CD) and ulcerative colitis (UC), which are characterized by chronic inflammation of the gastrointestinal (GI) tract. IBDs clinical manifestations are heterogeneous and characterized by a chronic relapsing-remitting course. Typical gastrointestinal signs and symptoms include diarrhea, GI bleeding, weight loss, and abdominal pain. Moreover, the presence of pain often manifests in the remitting disease phase. As a result, patients report a further reduction in life quality. Despite the scientific advances implemented in the last two decades and the therapies aimed at inducing or maintaining IBDs in a remissive condition, to date, their pathophysiology still remains unknown. In this scenario, the importance of identifying a common and effective therapeutic target for both digestive symptoms and pain remains a priority. Recent clinical and preclinical studies have reported the prokineticin system (PKS) as an emerging therapeutic target for IBDs. PKS alterations are likely to play a role in IBDs at multiple levels, such as in intestinal motility, local inflammation, ulceration processes, localized abdominal and visceral pain, as well as central nervous system sensitization, leading to the development of chronic and widespread pain. This narrative review summarized the evidence about the involvement of the PKS in IBD and discussed its potential as a druggable target.

Sphingosine 1-phosphate signaling during infection and immunity

Sphingolipids are essential components of all eukaryotic membranes. The bioactive sphingolipid molecule, Sphingosine 1-Phosphate (S1P), regulates various important biological functions. This review aims to provide a comprehensive overview of the role of S1P signaling pathway in various immune cell functions under different pathophysiological conditions including bacterial and viral infections, autoimmune disorders, inflammation, and cancer. We covered the aspects of S1P pathways in NOD/TLR pathways, bacterial and viral infections, autoimmune disorders, and tumor immunology. This implies that targeting S1P signaling can be used as a strategy to block these pathologies. Our current understanding of targeting various components of S1P signaling for therapeutic purposes and the present status of S1P pathway inhibitors or modulators in disease conditions where the host immune system plays a pivotal role is the primary focus of this review.

Causal association between inflammatory bowel disease and 32 site-specific extracolonic cancers: a Mendelian randomization study

BACKGROUND

The risk of extracolonic cancer is increased in inflammatory bowel disease (IBD) patients, but it is not clear whether there is a causal relationship. We aimed to systematically estimate the causal relationship between IBD and extracolonic cancers.

METHODS

Independent genetic variants strongly associated with IBD were extracted as instrumental variables from genome-wide association study (GWAS) conducted by the International IBD Genetics Consortium including 12,882 IBD patients, 5956 Crohn's disease (CD) patients, and 6968 ulcerative colitis (UC) patients. Three sources of cancer GWAS were selected as outcome data. Two-sample Mendelian randomization (MR) analysis was conducted to assess the causal effects of IBD on 32 extracolonic cancers. The meta-analysis was applied to assess the combined causal effect with multiple MR results.

RESULTS

IBD, CD, and UC have potential causal associations with oral cavity cancer (IBD: OR = 1.180, 95% CI: 1.059 to 1.316, P = 0.003; CD: OR = 1.112, 95% CI: 1.008 to 1.227, P = 0.034; UC: OR = 1.158, 95% CI: 1.041 to 1.288, P = 0.007). Meta-analysis showed a significant positive causal relationship between IBD and breast cancer (OR = 1.059; 95% CI: 1.033 to 1.086; P < 0.0001) as well as a potential causal relationship between CD and breast cancer (OR = 1.029; 95% CI: 1.002 to 1.055; P = 0.032) based on combining multiple MR results.

CONCLUSIONS

This comprehensive MR analysis suggested that genetically predicted IBD, as well as its subtypes, may be a risk factor in the development of oral cavity and breast cancer.

Case Report: Malignant melanoma in a patient with Crohn's disease treated with ustekinumab

The cornerstone of inflammatory bowel disease (IBD) treatment is immunomodulators. IBD patients are at increased risk of intestinal and extraintestinal malignancy. Ustekinumab is a fully humanized monoclonal anti-IL12/23 antibody with a good safety profile. Malignancies of breast, colon, head and neck, kidney, prostate, thyroid, and non-melanoma skin cancer have been reported among patients who received ustekinumab. We report the case of a 42-year-old Crohn's patient on long-term treatment with ustekinumab, who developed achromatic malignant melanoma. Crohn's was diagnosed at the age of 15, with upper and lower gastrointestinal involvement and was initially treated with azathioprine (2mg/kg for 4 years) and infliximab (5mg/kg for 6 weeks). Due to ileal obstruction, the patient underwent stricturoplasty and received adalimumab (40mg every other week) for two years. He then discontinued therapy and a year later underwent right hemicolectomy. Adalimumab was reinstituted (40mg every other week) and the patient remained in clinical remission for two years. His overall exposure to adalimumab was four years. Ustekinumab was initiated due to a relapse and after 3 years, an incident of scalp itching led to the diagnosis metastatic achromatic malignant melanoma bearing BRAF V600E mutation. He received targeted therapy with an initial good response. We aim to point out the risk of dermatologic malignancy in IBD patients on long-term immunosuppression and the lifelong and meticulous evaluation that is required.

Molecular Pathogenesis of Colitis-associated Colorectal Cancer: Immunity, Genetics, and Intestinal Microecology

Patients with inflammatory bowel disease (IBD) have a high risk for colorectal cancer (CRC). This cancer type, which is strongly associated with chronic inflammation, is called colitis-associated CRC (CAC). Understanding the molecular pathogenesis of CAC is crucial to identify biomarkers necessary for early diagnosis and more effective treatment directions. The accumulation of immune cells and inflammatory factors, which constitute a complex chronic inflammatory environment in the intestinal mucosa, may cause oxidative stress or DNA damage to the epithelial cells, leading to CAC development and progression. An important feature of CAC is genetic instability, which includes chromosome instability, microsatellite instability, hypermethylation, and changes in noncoding RNAs. Furthermore, the intestinal microbiota and metabolites have a great impact on IBD and CAC. By clarifying immune, genetic, intestinal microecology, and other related pathogenesis, CAC may be more predictable and treatable.

MicroRNA 452 regulates SHC1 expression in human colorectal cancer and colitis

BACKGROUND

Human microRNA 452 (MIR452) has been linked to both colorectal cancer (CRC) tissues and dextran sulfate sodium (DSS)-induced colitis.

OBJECTIVE

We analyzed the correlation between MIR452 and its putative target gene in human CRC cells and in mouse colitis tissues.

METHODS

Luciferase reporter assay confirmed that Src homologous and collagen adaptor protein 1 (SHC1) is a direct target of MIR452. Furthermore, the expression of proteins or mRNA was assessed by immunohistochemical analysis, Western blot, or quantitative RT-PCR (qRT-PCR).

RESULTS

We found that MIR452 has a potential binding site at 3'-UTR of SHC1. Likewise, MIR452 or siSHC1 transfection dramatically reduced the level of cellular SHC1 in CRC cells. The expression of SHC1 was frequently downregulated in both human CRC tissues and mouse colitis tissues. In CRC cells, we demonstrated that MIR452 regulated the expression of genes involved in the SHC1-mediated KRAS-MAPK signal transduction pathways.

CONCLUSION

These findings suggest a potential defense mechanism in which MIR452 regulation of the adaptor protein SHC1 maintains cellular homeostasis during carcinogenesis or chronic inflammation. Therefore, MIR452 may have therapeutic value for human early-stage CRC and colitis.

Serum Cytokine and miRNA Levels Are Differently Expressed in Right- and Left-Sided Colon Cancer

The tumor location in colorectal cancer (right- or left-sided colon cancer) is a key factor in determining disease progression. Right- and left-sided colon tumors are different in their clinical and molecular characteristics. Dysregulation of serum levels of proinflammatory cytokines, such as Transforming Growth Factor β (TGF-β) and Tumor Necrosis Factor-α (TNF-α), and Peroxisome Proliferator Activated Receptor-γ (PPAR-γ), known to be a growth-limiting and differentiation-promoting factor, as well as changes in miRNAs expression, are the major signaling pathways involved in the pathogenesis of this neoplasia. In the serum from 60 colorectal cancer (CRC) patients, we compared the differences in the expression of the levels of TGF-β, TNF-α, and PPAR-γ and in the expression of the main human miRNAs between right and left CRC. A significant over-expression in the TGF-β and TNF-α levels was observed in the serum from right-sided colon cancer patients. For the PPAR-γ, the patients with CRC located on the right-side showed lower levels than those detected in the serum from left-sided CRC subjects. Furthermore, significant differences also existed in the expression of specific circulating miRNAs between right- and left-sided CRC. In particular, the right upregulated miRNAs were all involved in the cell growth and proliferation related pathways. These findings confirm that the analysis of circulating levels of TGF-β, TNF-α, and PPAR-γ, as well as the study of the specific miRNAs in the serum, are able to identify specific characteristics of CRC patients, useful for choosing a personalized treatment protocol.

Phosphorylation of PPDPF via IL6-JAK2 activates the Wnt/β-catenin pathway in colorectal cancer

Inflammation plays an important role in the initiation and progression of colorectal cancer (CRC) and leads to β-catenin accumulation in colitis-related CRC. However, the mechanism remains largely unknown. Here, pancreatic progenitor cell differentiation and proliferation factor (PPDPF) is found to be upregulated in CRC and significantly correlated with tumor-node-metastasis (TNM) stages and survival time. Knockout of PPDPF in the intestinal epithelium shortens crypts, decreases the number of stem cells, and inhibits the growth of organoids and the occurrence of azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced CRC. Mechanistically, PPDPF is found to interact with Casein kinase 1α (CK1α), thereby disrupting its binding to Axin, disassociating the β-catenin destruction complex, decreasing the phosphorylation of β-catenin, and activating the Wnt/β-catenin pathway. Furthermore, interleukin 6 (IL6)/Janus kinase 2 (JAK2)-mediated inflammatory signals lead to phosphorylation of PPDPF at Tyr16 and Tyr17, stabilizing the protein. In summary, this study demonstrates that PPDPF is a key molecule in CRC carcinogenesis and progression that connects inflammatory signals to the Wnt/β-catenin signaling pathway, providing a potential novel therapeutic target.

HLA Class I Expression Is Associated with DNA Damage and Immune Cell Infiltration into Dysplastic and Neoplastic Lesions in Ulcerative Colitis

Human leukocyte antigen class I (HLA-I) is considered a genetic pathogen for ulcerative colitis (UC). This study aimed to investigate the significance of DNA damage and HLA-I expression in infiltrating immune cells and immune checkpoint protein PD-L1 expression in dysplasia/colitic cancer (CC) and sporadic colorectal cancer (SCRC). We performed immunohistochemical staining for HLA-I, PD-L1, γH2AX (DNA damage marker), and immune cell markers such as CD8, FOXP3, CD68, and CD163 (in surgically resected specimens from 17 SCRC patients with 12 adjacent normal mucosa (NM) and 9 UC patients with 18 dysplasia/CC tumors. The ratio of membrane HLA-I-positive epithelial cells in UC and dysplasia/CC tissues was significantly higher than that in NM and SCRC. High HLA-I expression in dysplasia/CC was associated with high positivity of γH2AX and PD-L1 expression compared to SCRC. The infiltration of CD8-positive T cells and CD68-positive macrophages in HLA-I-high dysplasia/CC was significantly higher than in UC and SCRC. Dysplasia/CC specimens with DNA damage exhibited high levels of HLA-I-positive epithelial cells with high CD8- and CD68-positive immune cell infiltration compared to UC and SCRC specimens. Targeting DNA damage in UC may regulate immune cell infiltration, immune checkpoint proteins, and carcinogenesis by modulating DNA damage-induced HLA-I antigen presentation.

The incidence of malignancy in the residual rectum of IBD patients after colectomy: a systematic review and meta-analysis

BACKGROUND

Patients with inflammatory bowel disease (IBD) who have had a total colectomy remain with their rectum in situ, and are therefore at risk of rectal carcinoma. It is not clear how high the incidence of rectal cancer is in this cohort. The primary objective of this meta-analysis was to estimate the incidence of rectal cancer in patients with ulcerative colitis or Crohn's disease who have undergone colectomy but have a residual rectum, and to identify the risk factors for its development. In doing so, we explore the current recommendations for screening processes for these patients.

METHODS

A systematic review of the literature was performed. Five databases (Medline, Embase, Pubmed, Cochrane Library and Scopus) were searched from inception to 29 October 2021, to identify studies adhering to the population, intervention, control and outcomes (PICO) criteria. The included studies were critically appraised, and the relevant data was extracted. Cancer incidence was estimated from the reported information. Risk stratification was analysed using RevMan. A narrative approach was undertaken for the exploration of the existing screening guidelines.

RESULTS

Data from 23 of the 24 identified studies was suitable for analysis. The pooled incidence of rectal carcinoma was calculated to be 1.3%. Subgroup analysis showed an incidence of 0.7% and 3.2% for patients with a de-functioned rectal stump and ileorectal anastomosis, respectively. Patients with a history of a colorectal carcinoma were more likely to have a subsequent diagnosis of rectal carcinoma (RR 7.2, 95% CI 2.4-21.1). Patients with previous colorectal dysplasia were also at higher risk (RR 5.1, 95% CI 3.1-8.2). No universal standardised guidance regarding screening for this cohort could be identified in the available literature.

CONCLUSIONS

The overall risk of malignancy was estimated to be 1.3%, which is lower than previously reported. There is a need for clear and standardised screening guidance for this group of patients.

Improving intestinal inflammaging to delay aging? A new perspective

Greying population is becoming an increasingly critical issue for social development. In advanced aging context, organismal multiple tissues and organs experience a progressive deterioration, initially presenting with functional decline, followed by structural disruption and eventually organ failure. The aging of the gut is one of the key links. Decreased gut function leads to reduced nutrient absorption and can perturb systemic metabolic rates. The degeneration of the intestinal structure causes the migration of harmful components such as pathogens and toxins, inducing pathophysiological changes in other organs through the "brain-gut axis" and "liver-gut axis". There is no accepted singular underlying mechanism of aged gut. While the inflamm-aging theory was first proposed in 2000, the mutual promotion of chronic inflammation and aging has attracted much attention. Numerous studies have established that gut microbiome composition, gut immune function, and gut barrier integrity are involved in the formation of inflammaging in the aging gut. Remarkably, inflammaging additionally drives the development of aging-like phenotypes, such as microbiota dysbiosis and impaired intestinal barrier, via a broad array of inflammatory mediators. Here we demonstrate the mechanisms of inflammaging in the gut and explore whether aging-like phenotypes in the gut can be negated by improving gut inflammaging.

Prognosis and molecular characteristics of IBD-associated colorectal cancer: Experience from a French tertiary-care center

BACKGROUND

Little is known about the prognosis of colorectal cancer associated with inflammatory bowel disease (CRC-IBD) in a real-world cohort in France.

METHODS

We conducted a retrospective observational study including all patients presenting CRC-IBD in a French tertiary center.

RESULTS

Among 6510 patients, the rate of CRC was 0.8% with a median delay of 19.5 years after IBD diagnosis (median age 46 years, ulcerative colitis 59%, initially localized tumor 69%). There was a previous exposure to immunosuppressants (IS) in 57% and anti-TNF in 29% of the cases. A RAS mutation was observed in only 13% of metastatic patients. OS of the whole cohort was 45 months. OS and PFS of synchronous metastatic patients was 20.4 months and 8.5 months respectively. Among the patients with localized tumor those previously exposed to IS had a better PFS (39 months vs 23 months; p = 0.05) and OS (74 vs 44 months; p = 0.03). The IBD relapse rate was 4%. No unexpected chemotherapy side-effect was observed CONCLUSIONS: OS of CRC-IBD is poor in metastatic patients although IBD is not associated with under-exposure or increased toxicity to chemotherapy. Previous IS exposure may be associated with a better prognosis.

Trinity of inflammation, innate immune cells and cross-talk of signalling pathways in tumour microenvironment

Unresolved inflammation is a pathological consequence of persistent inflammatory stimulus and perturbation in regulatory mechanisms. It increases the risk of tumour development and orchestrates all stages of tumorigenesis in selected organs. In certain cancers, inflammatory processes create the appropriate conditions for neoplastic transformation. While in other types, oncogenic changes pave the way for an inflammatory microenvironment that leads to tumour development. Of interest, hallmarks of tumour-promoting and cancer-associated inflammation are striking similar, sharing a complex network of stromal (fibroblasts and vascular cells) and inflammatory immune cells that collectively form the tumour microenvironment (TME). The cross-talks of signalling pathways initially developed to support homeostasis, change their role, and promote atypical proliferation, survival, angiogenesis, and subversion of adaptive immunity in TME. These transcriptional and regulatory pathways invariably contribute to cancer-promoting inflammation in chronic inflammatory disorders and foster "smouldering" inflammation in the microenvironment of various tumour types. Besides identifying common target sites of numerous cancer types, signalling programs and their cross-talks governing immune cells' plasticity and functional diversity can be used to develop new fate-mapping and lineage-tracing mechanisms. Here, we review the vital molecular mechanisms and pathways that establish the connection between inflammation and tumour development, progression, and metastasis. We also discussed the cross-talks between signalling pathways and devised strategies focusing on these interaction mechanisms to harness synthetic lethal drug combinations for targeted cancer therapy.

Inflammatory Bowel Disease and Colorectal Cancer: Epidemiology, Etiology, Surveillance, and Management

Patients with inflammatory bowel diseases (IBDs), such as ulcerative colitis and Crohn's disease, have an increased risk of developing colorectal cancer (CRC). Although advancements in endoscopic imaging techniques, integrated surveillance programs, and improved medical therapies have contributed to a decreased incidence of CRC in patients with IBD, the rate of CRC remains higher in patients with IBD than in individuals without chronic colitis. Patients with IBD-related CRCs exhibit a poorer prognosis than those with sporadic CRCs, owing to their aggressive histological characteristics and lower curative resection rate. In this review, we present an updated overview of the epidemiology, etiology, risk factors, surveillance strategies, treatment recommendations, and prognosis of IBD-related CRCs.

The alleviating effect of ellagic acid on DSS-induced colitis via regulating gut microbiomes and gene expression of colonic epithelial cells

The anti-inflammatory effect of ellagic acid (EA) and its possible underlying mechanism in dextran sulfate sodium (DSS)-induced mouse chronic colonic inflammation were studied. It was observed that EA administration significantly alleviated the colonic inflammation phenotypes, including decreasing the disease activity index (DAI), enhancing the body weight loss, and improving the shortened length of the colon and pathological damage of colon tissue. Additionally, EA reshaped the constitution of the gut microbiota by elevating the ratio of Bacteroidetes along with Bacteroides and Muribaculaceae, while decreasing the proportion of Firmicutes. The Phylogenetic Investigation of Communities by Reconstruction of Unobserved States 2 (PICRUSt2) revealed that the metabolic function of the gut microbiota was also changed. Furthermore, mouse colon transcriptome analysis showed that the tight junction and peroxisome proliferator-activated receptor (PPAR) signaling pathways were activated and the expressions of related genes were upregulated after EA intervention. These results showed that EA could remodel the gut bacterial composition, change the intestinal epithelial cell gene expressions in mice, and consequently improve the colonic inflammatory symptoms.

Influence of food emulsifiers on cellular function and inflammation, a preliminary study

Emulsifiers are extensively used as food additives and their consumption is increasing in Western countries. However, so far only few studies examined their potential effects on intestinal cellular functions and gut inflammation. The aim of this preliminary analysis was to study the emulsifiers and their concentrations capable of causing cellular damage compared to extra virgin olive oil (EVOO). We tested two commonly used emulsifiers (EMI, EMII) and EVOO on Caco-2 cells, derived from a colon carcinoma and widely used as a model of the intestinal inflammation. The diphenyltetrazolium bromide test MTT and clonogenic assay were used to study the effect of emulsifiers on cell viability. Cell migration was determined by the wound-healing assay. The inflammation was studied by measuring the levels of interleukin 6 (IL-6) and monocyte chemoattractant protein-1/C-C motif chemokine ligand 2 (CCL2), multifunctional cytokines with a major role in the acute-phase response. Furthermore, we analyzed the effect of conditioned media of Caco-2 cells treated with EMs on macrophages activation. In conclusion, our preliminary data provide evidence that EMs increase the proliferation and migration rate of Caco-2 cells. Moreover, Caco-2 cells treated with EMs enhance the IL-6 and CCL2 release and activated macrophages, supporting their role as proinflammatory molecules.

Detection of Fusobacterium nucleatum in Patients with Colitis-Associated Colorectal Cancer

Fusobacterium nucleatum is supposed to play a critical role in the development of colorectal cancer. The species has also been associated with ulcerative colitis (UC) that can progress into colorectal cancer, however, the involvement of bacteria in this process remains unclear. We analysed 177 colon biopsies obtained from patients during screening, including 20 healthy controls, 56 UC cases and 69 cases at different stages of progression to colitis-associated cancer (CAC); 32 samples of sporadic colorectal carcinoma (sCRC) were also included. The presence of F. nucleatum was detected by quantitative real-time PCR (qPCR). Our data show an association between the presence of the bacteria and the progression of carcinogenesis in UC patients. In 39.5% of CAC samples F. nucleatum was detected, compared to only 1.8% in UC cases. The bacteria were detected in 6.3% of samples with initial neoplastic transformation, so-called low-grade dysplasia (LGD), whereas high-grade dysplasia (HGD) resulted in 33.3% of samples positive for F. nucleatum. The fraction of F. nucleatum-positive samples from sCRC cases was 56.3%, which was not significantly different to the CAC group. We conclude that F. nucleatum is associated with the occurrence and progression of colon carcinogenesis, rather than with UC itself.

Risk Factors of Cancer in Pediatric-Onset Inflammatory Bowel Disease in Denmark and Finland

OBJECTIVES

Pediatric-onset inflammatory bowel disease (pIBD) increases the risk of developing several different cancer forms. In this case-control study, we aimed to assess the impact of medical treatment and disease activity on the risk of developing disease-associated cancer (DAC) and treatment-associated cancer (TAC).

METHODS

In a previous study, we identified 27 cases of DAC (colorectal cancer, small bowel cancer, and cholangiocarcinoma) and 28 TAC (lymphoma and skin cancer) in 6689 patients with pIBD in Denmark and Finland during the period 1992-2015. In this study, the patient charts were reviewed manually. Cancer-free patients from another population-based pIBD cohort were included as controls. We recorded data on phenotype, medical treatment, surgery, and relapses. Logistic regression was used to estimate adjusted odds ratios (aOR) with 95% confidence intervals (95% CI) to estimate the relative risk.

RESULTS

We included 16 cases with DAC, 21 with TAC, and 331 controls. For DAC, lower frequencies of IBD-relapses were associated with an increased risk of cancer (OR 0.2 [95% CI: 0.04-0.8]). For TAC, we found an increased risk in patients receiving thiopurines at any point during the follow-up period (aOR: 11.7 [95% CI: 2.1-116.2]) and an association with proportion of follow-up time being exposed to thiopurines (aOR 5.6 [95% CI: 1.1-31.5]).

CONCLUSIONS

In this nation-wide study, covering all pIBD patients from Denmark and Finland, we found that pIBD patients treated with thiopurines had an increased risk of TAC.

In Vivo Staging the Progression of Colitis and Associated Cancer by Concurrent Microimaging of Key Biomarkers

Currently colorectal cancer (CRC) staging (colitis, adenoma, and carcinoma) mainly relies on ex vivo pathologic analysis requiring an invasive surgical process with limited sample collection and increased metastatic risk. Thus, in vivo noninvasive pathological diagnosis is extremely demanded. By verifying the samples of clinical patients and CRC mouse models, it was found that vascular endothelial growth factor receptor 2 (VEGFR2) was barely expressed in the colitis stage and only appeared in adenoma and carcinoma stages with obvious elevation, while prostaglandin E receptor 4 (PTGER4) could be observed from colitis to adenoma and carcinoma stages with a gradient increase of expression. VEGFR2 and PTGER4 were further chosen as key biomarkers for molecular pathological diagnosis in vivo and corresponding molecular probes were constructed. The feasibility of in vivo noninvasive CRC staging by concurrent microimaging of dual biomarkers using confocal laser endoscopy (CLE) was verified in CRC mouse models and further confirmed by ex vivo pathological analysis. In vivo CLE imaging exhibited the correlation of severe colonic crypt structural alteration with a higher biomarker expression in adenoma and carcinoma stages. This strategy shows promise in benefiting patients undergoing CRC progression with in-time, noninvasive, and precise pathological staging, thus providing valuable guidance for selecting therapeutic strategies.

Quantitative Phase Imaging Using Digital Holographic Microscopy to Assess the Degree of Intestinal Inflammation in Patients with Ulcerative Colitis

Ulcerative colitis (UC) is characterized by chronic inflammation of the colorectum. Histological remission has emerged as a potential future treatment goal; however, the histopathological assessment of intestinal inflammation in UC remains challenging with a multitude of available scoring systems and the need for a pathologist with expertise in inflammatory bowel disease (IBD). In previous studies, quantitative phase imaging (QPI) including digital holographic microscopy (DHM) was successfully applied as an objective method for stain-free quantification of the degree of inflammation in tissue sections. Here, we evaluated the application of DHM for the quantitative assessment of histopathological inflammation in patients with UC. In our study, endoscopically obtained colonic and rectal mucosal biopsy samples from 21 patients with UC were analyzed by capturing DHM-based QPI images that were subsequently evaluated using the subepithelial refractive index (RI). The retrieved RI data were correlated with established histological scoring systems including the Nancy index (NI) as well as with endoscopic and clinical findings. As a primary endpoint, we found a significant correlation between the DHM-based retrieved RI and the NI (R² = 0.251, p < 0.001). Furthermore, RI values correlated with the Mayo endoscopic subscore (MES; R² = 0.176, p < 0.001). An area under the receiver operating characteristics (ROC) curve of 0.820 confirms the subepithelial RI as a reliable parameter to distinguish biopsies with histologically active UC from biopsies without evidence of active disease as determined by conventional histopathological examination. An RI higher than 1.3488 was found to be the most sensitive and specific cut-off value to identify histologically active UC (sensitivity of 84% and specificity of 72%). In conclusion, our data demonstrate DHM to be a reliable tool for the quantitative assessment of mucosal inflammation in patients with UC.

Berberine induces SOCS1 pathway to reprogram the M1 polarization of macrophages via miR-155-5p in colitis-associated colorectal cancer

Berberine is approved for the treatment of intestinal infections and diarrhea and has been shown to have anti-inflammatory and anti-tumor effects in pathological intestinal tissues. However, it is unclear whether the anti-inflammatory effect of berberine contributes to its anti-tumor effect on colitis-associated colorectal cancer (CAC). In this study, we found that berberine effectively inhibited tumorigenesis and protected against colon shortening in CAC mouse model. Immunohistochemistry results showed a reduction in the number of macrophage infiltrations in the colon following berberine treatment. Further analysis revealed that most of the infiltrated macrophages were pro-inflammatory M1 type, which berberine effectively limited. However, in another CRC model without chronic colitis, berberine had no significant effect on tumor number or colon length. In vitro studies demonstrated that berberine treatment significantly reduced the percentage of M1 type and levels of Interleukin-1β (IL-1β), Interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). Additionally, miR-155-5p level was down-regulated, and suppressor of cytokine signaling 1 (SOCS1) expression was up-regulated in berberine-treated cells. Notably, the miR-155-5p inhibitor attenuated the regulatory effects of berberine on SOCS1 signaling and macrophage polarization. Altogether, our findings suggest that the inhibitory effect of berberine on CAC development is dependent on its anti-inflammatory activity. Moreover, miR-155-5p may be involved in the pathogenesis of CAC by regulating M1 macrophage polarization, and berberine could be a promising protective agent against miR-155-5p-mediated CAC. This study provides new insights into pharmacologic mechanisms of berberine and supports the possibility that other anti-miR-155-5p drugs may be beneficial in the treatment of CAC.

Inflammatory Bowel Disease Treatment in Cancer Patients-A Comprehensive Review

Inflammatory bowel disease (IBD) is a chronic disease for which medical treatment with immunomodulating drugs is increasingly used earlier to prevent disability. Additionally, cancer occurrence in IBD patients is increased for several reasons, either IBD-related or therapy-associated. Doctors are therefore facing the challenge of managing patients with IBD and a past or current malignancy and the need to balance the risk of cancer recurrence associated with immunosuppressive drugs with the potential worsening of IBD activity if they are withdrawn. This review aims to explore the features of different subtypes of cancer occurring in IBD patients to present current evidence on malignancy recurrence risk associated with IBD medical therapy along with the effects of cancer treatment in IBD and finally to discuss current recommendations on the management of these patients. Due to sparse data, a case-by-case multidisciplinary discussion is advised, including inputs from the gastroenterologist, oncologist, and patient.

Therapeutic Potential of a Small-Molecule STAT3 Inhibitor in a Mouse Model of Colitis

BACKGROUND AND AIMS

Inflammatory bowel disease (IBD) predisposes to colorectal cancer (CRC). In the current studies, we used the dextran sodium sulfate (DSS) murine model of colitis, which is widely used in preclinical studies, to determine the contribution of STAT3 to IBD. STAT3 has two isoforms: (STAT3 α; which has pro-inflammatory and anti-apoptotic functions, and STAT3β; which attenuates the effects of STAT3α). In the current study, we determined the contribution of STAT3 to IBD across all tissues by examining DSS-induced colitis in mice that express only STAT3α and in mice treated with TTI-101, a direct small-molecule inhibitor of both isoforms of STAT3.

METHODS

We examined mortality, weight loss, rectal bleeding, diarrhea, colon shortening, apoptosis of colonic CD4+ T-cells, and colon infiltration with IL-17-producing cells following 7-day administration of DSS (5%) to transgenic STAT3α knock-in (STAT3β-deficient; ΔβΔβ) mice and wild-type (WT) littermate cage control mice. We also examined the effect of TTI-101 on these endpoints in DSS-induced colitis in WT mice.

RESULTS

Each of the clinical manifestations of DSS-induced colitis examined was exacerbated in ΔβΔβ transgenic versus cage-control WT mice. Importantly, TTI-101 treatment of DSS-administered WT mice led to complete attenuation of each of the clinical manifestations and also led to increased apoptosis of colonic CD4+ T cells, reduced colon infiltration with IL-17-producing cells, and down-modulation of colon mRNA levels of STAT3-upregulated genes involved in inflammation, apoptosis resistance, and colorectal cancer metastases.

CONCLUSIONS

Thus, small-molecule targeting of STAT3 may be of benefit in treating IBD and preventing IBD-associated colorectal cancer.

Dextran-Sulfate-Sodium-Induced Colitis-Ameliorating Effect of Aqueous Phyllanthus emblica L. Extract through Regulating Colonic Cell Gene Expression and Gut Microbiomes

The anti-inflammation effect of aqueous Phyllanthus emblica L. extract (APE) and its possible underlying mechanism in dextran sulfate sodium (DSS)-induced mice chronic colonic inflammation were studied. APE treatment significantly improved the colitic symptoms, including ameliorating the shortening of the colon, increasing the DSS-induced body weight loss, reducing the disease activity index, and reversing the condition of colon tissue damage of mucus lost and goblet cell reduction. Overproduction of serum pro-inflammatory cytokines were suppressed by the treatment of APE. Gut microbiome analysis showed that APE remodeled the structure of gut bacteria in phylum and genus levels, upregulating the abundance of phylum Bacteroidetes, family Muribaculaceae, and genus Bacteroides and downregulating the abundance of phylum Firmicutes. The reshaped gut microbiome caused metabolic functions and pathway change with enhanced queuosine biosynthesis and reduced polyamine synthesis pathway. Colon tissue transcriptome analysis further elucidated APE-inhibited mitogen-activated protein kinase (MAPK), cytokine-cytokine receptor interaction, and tumor necrosis factor (TNF) signaling pathways and the expressions of the genes that promote the progress of colorectal cancer. It turned out that APE reshaped the gut microbiome and inhibited MAPK, cytokine-cytokine receptor interaction, and TNF signaling pathways as well as the colorectal-cancer-related genes to exert its colitis protective effect.

Low risk of new dysplastic lesions in an inflammatory bowel disease population study with dye chromoendoscopy

Background and study aims  Rates of new dysplastic lesions or cancer progression after first dye chromoendoscopy in the era of high-definition endoscopy have yet to be determined. Patients and methods  A multicenter, population-based, retrospective cohort study was performed in seven hospitals in Spain. Patients with inflammatory bowel disease and fully resected (R0) dysplastic colon lesions under surveillance with high-definition dye-based chromoendoscopy were sequentially enrolled between February 2011 and June 2017, with a minimum endoscopic follow-up of 36 months. The aim was to assess the incidence of developing more advanced metachronous neoplasia by analyzing possible associated risk factors. Results  The study sample included 99 patients and 148 index lesions (145 low-grade dysplasia lesions and three high-grade dysplasia [HGD] lesions with a mean follow-up of 48.76 months [IQR: 36.34-67.15]). The overall incidence of new dysplastic lesions was 0.23 per 100 patient-years, 1.15 per 100 patients at 5 years and 2.29 per 100 patients at 10 years. A history of dysplasia was associated with a higher risk of developing any grade of dysplasia during follow-up ( P  = 0.025), whereas left colon lesions were associated with a lower risk ( P  = 0.043). The incidence of more advanced lesions at 1 year and 10 years was 1 % and 14 % respectively, with lesion size > 1 cm being a risk factor ( P  = 0.041). One of the eight patients (13 %) with HGD lesions developed colorectal cancer during follow-up. Conclusions  The risk of dysplasia progressing to advanced neoplasia and, specifically, the risk of new neoplastic lesions after endoscopic resection of colitis-associated dysplasia, are both very low.

Protein stabilization of ITF2 by NF-κB prevents colitis-associated cancer development

Chronic colonic inflammation is a feature of cancer and is strongly associated with tumorigenesis, but its underlying molecular mechanisms remain poorly understood. Inflammatory conditions increased ITF2 and p65 expression both ex vivo and in vivo, and ITF2 and p65 showed positive correlations. p65 overexpression stabilized ITF2 protein levels by interfering with the binding of Parkin to ITF2. More specifically, the C-terminus of p65 binds to the N-terminus of ITF2 and inhibits ubiquitination, thereby promoting ITF2 stabilization. Parkin acts as a E3 ubiquitin ligase for ITF2 ubiquitination. Intestinal epithelial-specific deletion of ITF2 facilitated nuclear translocation of p65 and thus increased colitis-associated cancer tumorigenesis, which was mediated by Azoxymethane/Dextran sulfate sodium or dextran sulfate sodium. Upregulated ITF2 expression was lost in carcinoma tissues of colitis-associated cancer patients, whereas p65 expression much more increased in both dysplastic and carcinoma regions. Therefore, these findings indicate a critical role for ITF2 in the repression of colitis-associated cancer progression and ITF2 would be an attractive target against inflammatory diseases including colitis-associated cancer.

Oxidative Stress, Inflammation and Colorectal Cancer: An Overview

Colorectal cancer (CRC) represents the second leading cause of cancer-related deaths worldwide. The pathogenesis of CRC is a complex multistep process. Among other factors, inflammation and oxidative stress (OS) have been reported to be involved in the initiation and development of CRC. Although OS plays a vital part in the life of all organisms, its long-term effects on the human body may be involved in the development of different chronic diseases, including cancer diseases. Chronic OS can lead to the oxidation of biomolecules (nucleic acids, lipids and proteins) or the activation of inflammatory signaling pathways, resulting in the activation of several transcription factors or the dysregulation of gene and protein expression followed by tumor initiation or cancer cell survival. In addition, it is well known that chronic intestinal diseases such as inflammatory bowel disease (IBD) are associated with an increased risk of cancer, and a link between OS and IBD initiation and progression has been reported. This review focuses on the role of oxidative stress as a causative agent of inflammation in colorectal cancer.

F4/80+Ly6Chigh Macrophages Lead to Cell Plasticity and Cancer Initiation in Colitis

BACKGROUND & AIMS

Colorectal cancer is a leading cause of cancer death, and a major risk factor is chronic inflammation. Despite the link between colitis and cancer, the mechanism by which inflammation leads to colorectal cancer is not well understood.

METHODS

To investigate whether different forms of inflammation pose the same risk of cancer, we compared several murine models of colitis (dextran sodium sulfate [DSS], 2,4,6-trinitrobenzene sulfonic acid, 4-ethoxylmethylene-2-phenyloxazol-5-one, Citrobacter rodentium, Fusobacterium nucleatum, and doxorubicin) with respect to their ability to lead to colonic tumorigenesis. We attempted to correlate the severity of colitis and inflammatory profile with the risk of tumorigenesis in both azoxymethane-dependent and Dclk1/APCfl/fl murine models of colitis-associated cancer.

RESULTS

DSS colitis reproducibly led to colonic tumors in both mouse models of colitis-associated cancer. In contrast, all other forms of colitis did not lead to cancer. When compared with the colitis not associated with tumorigenesis, DSS colitis was characterized by significantly increased CD11b+F4/80+Ly6Chigh macrophages and CD11b+Ly6G+ neutrophils. Interestingly, depletion of the CD11b+F4/80+Ly6Chigh macrophages inhibited tumorigenesis, whereas depletion of CD11b+Ly6G+ neutrophils had no effect on tumorigenesis. Furthermore, the macrophage-derived cytokines interleukin-1β, tumor necrosis factor-α, and interleukin-6 were significantly increased in DSS colitis and promoted stemness of Dclk1+ tuft cells that serve as the cellular origin of cancer.

CONCLUSIONS

We have identified CD11b+F4/80+Ly6Chigh macrophages as key mediators of cancer initiation in colitis-associated cancer. Development of new therapies that target these cells may provide an effective preventative strategy for colitis-associated cancer.

NF-κB Activator 1 downregulation in macrophages activates STAT3 to promote adenoma-adenocarcinoma transition and immunosuppression in colorectal cancer

BACKGROUND

Adenoma-adenocarcinoma transition is a key feature of colorectal cancer (CRC) occurrence and is closely regulated by tumor-associated macrophages (TAMs) and CD8⁺ T cells. Here, we investigated the effect of the NF-κB activator 1 (Act1) downregulation of macrophages in the adenoma-adenocarcinoma transition.

METHODS

This study used spontaneous adenoma-developing Apc^Min/+, macrophage-specific Act1-knockdown (anti-Act1), and Apc^Min/+; anti-Act1 (AA) mice. Histological analysis was performed on CRC tissues of patients and mice. CRC patients' data retrieved from the TCGA dataset were analyzed. Primary cell isolation, co-culture system, RNA-seq, and fluorescence-activated cell sorting (FACS) were used.

RESULTS

By TCGA and TISIDB analysis, the downregulation of Act1 expression in tumor tissues of CRC patients negatively correlated with accumulated CD68⁺ macrophages in the tumor. Relative expression of EMT markers in the tumor enriched ACT1^lowCD68⁺ macrophages of CRC patients. AA mice showed adenoma-adenocarcinoma transition, TAMs recruitment, and CD8⁺ T cell infiltration in the tumor. Macrophages depletion in AA mice reversed adenocarcinoma, reduced tumor amounts, and suppressed CD8⁺ T cell infiltration. Besides, macrophage depletion or anti-CD8a effectively inhibited metastatic nodules in the lung metastasis mouse model of anti-Act1 mice. CRC cells induced activation of IL-6/STAT3 and IFN-γ/NF-κB signaling and the expressions of CXCL9/10, IL-6, and PD-L1 in anti-Act1 macrophages. Anti-Act1 macrophages facilitated epithelial-mesenchymal-transition and CRC cells' migration via CXCL9/10-CXCR3-axis. Furthermore, anti-Act1 macrophages promoted exhaustive PD1⁺ Tim3⁺ CD8⁺ T cell formation. Anti-PD-L1 treatment repressed adenoma-adenocarcinoma transition in AA mice. Silencing STAT3 in anti-Act1 macrophages reduced CXCL9/10 and PD-L1 expression and correspondingly inhibited epithelial-mesenchymal-transition and CRC cells' migration.

CONCLUSIONS

Act1 downregulation in macrophages activates STAT3 that promotes adenoma-adenocarcinoma transition via CXCL9/10-CXCR3-axis in CRC cells and PD-1/PD-L1-axis in CD8⁺ T cells.

Prevention of malignant digestive system tumors should focus on the control of chronic inflammation

Chronic inflammation, through a variety of mechanisms, plays a key role in the occurrence and development of digestive system malignant tumors (DSMTs). In this study, we feature and provide a comprehensive understanding of DSMT prevention strategies based on preventing or controlling chronic inflammation. The development and evaluation of cancer prevention strategies is a longstanding process. Cancer prevention, especially in the early stage of life, should be emphasized throughout the whole life course. Issues such as the time interval for colon cancer screening, the development of direct-acting antiviral drugs for liver cancer, and the Helicobacter pylori vaccine all need to be explored in long-term, large-scale experiments in the future.

[Conventional and non-conventional dysplasia in patients with inflammatory bowel disease]

Compared to the general population, patients with inflammatory bowel disease (IBD), both ulcerative colitis (UC) or Crohn's disease (CD), are at increased risk of developing some cancers, particularly colorectal cancers (CRC). CRCs, the vast majority of which are adenocarcinomas, develop from a precancerous lesion called dysplasia (or intraepithelial neoplasia) via an inflammation-dysplasia-adenocarcinoma sequence. The advancements of new endoscopic techniques, including visualisation and resection techniques, has led to a reclassification of dysplasia lesions into visible and invisible lesions and their therapeutic management, with a more conservative approach to the colorectal setting. In addition, besides conventional dysplasia, of intestinal phenotype, classically described in IBD, non-conventional dysplasias (as opposed to conventional dysplasia of intestinal phenotype) are now described, including at least seven subtypes. Recognition of these unconventional subtypes, which are still poorly known from pathologists, is becoming crucial, as some of these subtypes appear to be at high risk of developing advanced neoplasia (i.e. high-grade dysplasia or CRC). This review briefly describes the macroscopic features of dysplastic lesions in IBD, as well as their therapeutic management, followed by the clinicopathological features of these dysplastic lesions, with particular emphasis on the new subtypes of unconventional dysplasia, both from a morphological and molecular point of view.

Oral Administration of Nanoformulated Indoximod Ameliorates Ulcerative Colitis by Promoting Mitochondrial Function and Mucosal Healing

Ulcerative colitis (UC) is a chronic relapsing inflammatory bowel disease with serious mucosal inflammation mainly in the colon and rectum. Currently, there is no effective therapeutics for UC. Indoximod (IND) is a water-insoluble inhibitor for indolamine 2, 3-dioxygenase (IDO) and has been mainly reported in cancer therapy. Here, we prepared orally administrated IND nanoparticles (IND-NPs) for UC treatment and investigated their functions and mechanisms in cellular and animal inflammatory models. Confocal imaging demonstrated that IND-NPs maintained the expression level of ZO-1, Occludin and E-cadherin, thereby stabilizing of intercellular junction in Caco-2 cells. It was found that IND-NPs could lower the ROS level and increase mitochondrial membrane potential as well as ATP level, indicating that IND-NPs could restore DSS-induced mitochondrial dysfunction. In the mice model with DSS-induced colitis, IND-NPs were found to alleviate UC-associated symptoms, inhibit inflammatory response, and improve the integrity of epithelial barrier. The untargeted metabolomics analysis validated that IND-NPs also contributed to regulate the metabolite levels to normal. As an agonist of aryl hydrocarbon receptor (AhR), IND-NPs might repair mucosa via the AhR pathway. These findings demonstrated that IND-NPs prominently ameliorated DSS-induced colonic injury and inflammation and preserved intestinal barrier integrity, showing a promising potential in UC treatment.

Surveillance for Colorectal Neoplasia in Inflammatory Bowel Disease: When to Stop

Patients with chronic ulcerative and Crohn's colitis are at increased risk for colorectal neoplasia(CRN [dysplasia and cancer]) compared to the general population. Risk factors for CRN include extent of colitis, cumulative inflammatory burden, family history of colorectal cancer, and primary sclerosing cholangitis. Best practices to prevent CRN include control of colonic inflammation, high quality surveillance colonoscopy with or without enhanced imaging techniques, resection of visible dysplasia if possible, and colectomy in patients with unresectable dysplasia, invisible multifocal low grade dysplasia, or invisible high grade dysplasia. Cessation of dysplasia surveillance is individualized and should involve shared decision making based on factors including but not limited to chronologic age, frailty, co-morbid conditions, life expectancy, results of prior surveillance exams, and risk factors for CRN.

Serrated polyps in patients with ulcerative colitis: Unique clinicopathological and biological characteristics

BACKGROUND

Serrated polyps have recently been reported in patients with ulcerative colitis (UC); however, their prevalence and detailed characteristics remain unclear.

METHODS

The prevalence and clinicopathological and biological characteristics of serrated polyps in patients with UC were retrospectively examined in a single tertiary inflammatory bowel disease center in Japan from 2000 to 2020.

RESULTS

Among 2035 patients with UC who underwent total colonoscopy, 252 neoplasms, including 36 serrated polyps (26 in colitis-affected segments, 10 in colitis-unaffected segments), were identified in 187 patients with UC. The proportion of serrated polyps was 1.8% (36/2035). Serrated polyps in colitis-affected segments were common with extensive colitis (88%), history of persistent active colitis (58%), and long UC duration (12.1 years). Serrated polyps in colitis-affected segments were more common in men (88%). Of the 26 serrated polyps in colitis-affected segments, 15, 6, and 5 were categorized as sessile serrated lesion-like dysplasia, traditional serrated adenoma-like dysplasia, and serrated dysplasia not otherwise specified, respectively. Sessile serrated lesion-like dysplasia was common in the proximal colon (67%) and with BRAF mutation (62%), whereas traditional serrated adenoma-like dysplasia and serrated dysplasia not otherwise specified were common in the distal colon (100% and 80%, respectively) and with KRAS mutations (100% and 75%, respectively).

CONCLUSIONS

Serrated polyps comprised 14% of the neoplasias in patients with UC. Serrated polyps in colitis-affected segments were common in men with extensive and longstanding colitis, suggesting chronic inflammation in the development of serrated polyps in patients with UC.

The Efficacy and Mechanism of Qinghua Jianpi Recipe in Inhibiting Canceration of Colorectal Adenoma Based on Inflammatory Cancer Transformation

Objective

This study is aimed at exploring the effect of Qinghua Jianpi Recipe on preventing colon polyp recurrence and inhibiting the progress of "inflammatory cancer transformation." And another goal is to explore the changes of intestinal flora structure and intestinal inflammatory (immune) microenvironment of mice with colon polyps treated by Qinghua Jianpi Recipe and to clarify its mechanism.

Methods

Clinical trials were conducted to confirm the therapeutic effect of Qinghua Jianpi Recipe on patients with inflammatory bowel disease. The inhibitory effect of Qinghua Jianpi Recipe on "inflammatory cancer transformation" of colon cancer was confirmed by an adenoma canceration mouse model. Histopathological examination was used to evaluate the effects of Qinghua Jianpi Recipe on intestinal inflammatory state, adenoma number, and pathological changes of adenoma model mice. The changes of inflammatory indexes in intestinal tissue were tested by ELISA. Intestinal flora was detected by 16S rRNA high-throughput sequencing. Short-chain fatty acid metabolism in the intestine was analyzed by targeted metabolomics. Network pharmacology analysis of possible mechanism of Qinghua Jianpi Recipe on colorectal cancer was performed. Western blot was used to detect the protein expression of the related signaling pathways.

Results

Qinghua Jianpi Recipe can significantly improve intestinal inflammation status and function in patients with inflammatory bowel disease. Qinghua Jianpi Recipe could significantly improve the intestinal inflammatory activity and pathological damage of adenoma model mice and reduce the number of adenoma. Qinghua Jianpi Recipe significantly increased the levels of Peptostreptococcales_Tissierellales, NK4A214_group, Romboutsia, and other intestinal flora after intervention. Meanwhile, the treatment group of Qinghua Jianpi Recipe could reverse the changes of short-chain fatty acids. Network pharmacology analysis and experimental studies showed that Qinghua Jianpi Recipe inhibited the "inflammatory cancer transformation" of colon cancer by regulating intestinal barrier function-related proteins, inflammatory and immune-related signaling pathways, and free fatty acid receptor 2 (FFAR2).

Conclusion

Qinghua Jianpi Recipe can improve the intestinal inflammatory activity and pathological damage of patient and adenoma cancer model mice. And its mechanism is related to the regulation of intestinal flora structure and abundance, short-chain fatty acid metabolism, intestinal barrier function, and inflammatory pathways.

Identifying neutrophil-associated subtypes in ulcerative colitis and confirming neutrophils promote colitis-associated colorectal cancer

Background

Ulcerative colitis (UC) is a chronic inflammatory disease of the intestinal mucosa, the incidence of which has increased worldwide. There is still a lack of clear understanding of the pathogenesis of ulcerative colitis that ultimately leads to colitis-associated colorectal cancer.

Method

We download UC transcriptome data from the GEO database and pass the limma package in order to identify differentially expressed genes. Gene Set Enrichment Analysis (GSEA) was used to identify potential biological pathways. We identified immune cells associated with UC by CIBERSORT and Weighted co-expression network analysis (WGCNA). We used validation cohorts and mouse models to verify the expression of the hub genes and the role of neutrophils.

Result

We identified 65 differentially expressed genes in UC samples and healthy controls. GSEA, KEGG, and GO analyses displayed that DEGs were enriched in immune-related pathways. CIBERSORT analysis revealed increased infiltration of neutrophils in UC tissues. The red module, obtained by WGCNA analysis, was considered to be the most relevant module for neutrophils.Based on neutrophil-associated differentially expressed genes, UC patients were classified into two subtypes of neutrophil infiltration. We discovered that the highly neutrophil-infiltrated subtype B of UC patients had a higher risk of developing CAC. Five genes were identified as biomarkers by searching for DEGs between distinct subtypes. Finally, using the mouse model, we determined the expression of these five genes in the control, DSS, and AOM/DSS groups. The degree of neutrophil infiltration in mice and the percentage of MPO and pSTAT3 expression in neutrophils were analyzed by flow cytometry. In the AOM/DSS model, MPO and pSTAT3 expressions were significantly increased.

Conclusions

These findings suggested neutrophils might promote the conversion of UC into CAC. These findings improve our understanding of the pathogenesis of CAC and provide new and more effective insights into the prevention and treatment of CAC.