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

Molecular Mechanisms and Clinical Aspects of Colitis-Associated Cancer in Ulcerative Colitis

Inflammatory bowel diseases have long been recognized as entities with a higher risk of colorectal cancer. An increasing amount of information has been published regarding ulcerative colitis-associated colorectal cancer and its unique mechanisms in recent decades, as ulcerative colitis constitutes a chronic process characterized by cycles of activity and remission of unpredictable durations and intensities; cumulative genomic alterations occur during active disease and mucosal healing, resulting in a special sequence of events different to the events associated with sporadic colorectal cancer. The recognition of the core differences between sporadic colorectal cancer and colitis-associated cancer is of great importance to understand and guide the directions in which new research could be performed, and how it could be applied to current clinical scenarios. A DSS/AOM murine model has allowed for a better understanding of the pathogenic mechanisms in colitis-associated cancer, as it is currently the closest model to this unique scenario. In this review, we provide a summary of the main molecular mechanisms and the clinical aspects of colitis-associated cancer in ulcerative colitis.

Neutrophils: From Inflammatory Bowel Disease to Colitis-Associated Colorectal Cancer

Inflammatory bowel disease (IBD) is a non-specific inflammatory disease of digestive tract, primarily manifesting as ulcerative colitis (UC) and Crohn's disease (CD). The precise etiology of IBD remains elusive. The interplay of genetic factors, environmental influences, and intestinal microbiota contributes to the establishment of an uncontrolled immune environment within the intestine, which can progressively lead to atypical hyperplasia and ultimately to malignancy over a long period. This colorectal malignant tumor that arises from chronic IBD is referred to as colitis-associated colorectal cancer (CAC). Dysregulation in the quantity and functionality of neutrophils plays a significant role in the onset, progression, and recurrence of IBD, as well as in the transition from IBD to CAC. Neutrophils affect the pathophysiology of IBD through various mechanisms, including the production of reactive oxygen species (ROS), degranulation, the release of inflammatory mediators and chemokines, and the formation of neutrophil extracellular traps (NETs). These processes can induce DNA mutations, thereby facilitating the development of colon cancer. Given the incomplete understanding of the disease mechanisms underlying IBD and CAC, effective treatment and prevention strategies remain challenging. Consequently, a comprehensive review of the functional roles of neutrophils in IBD and CAC is essential for advancing our understanding of IBD pathogenesis and identifying potential therapeutic targets.

Natural compounds modulate the mechanism of action of tumour-associated macrophages against colorectal cancer: a review

Colorectal cancer (CRC) exhibits a substantial morbidity and mortality rate, with its aetiology and pathogenesis remain elusive. It holds significant importance within the tumour microenvironment (TME) and exerts a crucial regulatory influence on tumorigenesis, progression, and metastasis. TAMs possess the capability to foster CRC pathogenesis, proliferation, invasion, and metastasis, as well as angiogenesis, immune evasion, and tumour resistance. Furthermore, TAMs can mediate the prognosis of CRC. In this paper, we review the mechanisms by which natural compounds target TAMs to exert anti-CRC effects from the perspective of the promotional effects of TAMs on CRC, mainly regulating the polarization of TAMs, reducing the infiltration and recruitment of TAMs, enhancing the phagocytosis of macrophages, and regulating the signalling pathways and cytokines, and discuss the potential value and therapeutic strategies of natural compounds-targeting the TAMs pathway in CRC clinical treatment.

Dual-layer probiotic encapsulation using metal phenolic network with gellan gum-tamarind gum coating for colitis treatment

Probiotic oral therapy has been recognised as an effective treatment for inflammatory bowel disease (IBD). However, the efficacy of probiotics is often diminished due to their limited resistance to harsh gastrointestinal conditions. Therefore, the importance of designing innovative strategies for oral probiotic delivery for the effective treatment of IBD is increasingly recognised. In this study, we present a novel encapsulation strategy of Lactobacillus plantarum (L.P) using the dual-layer system consisting of a tannic acid‑calcium network and polysaccharide coating (gellan gum-tamarind gum) named L.P-C/T-G/T. This double-layer encapsulation system not only does not affect the normal proliferation of probiotics and provide protection, but also endows probiotics with more functions. More specifically, the acid resistance ability of the encapsulated probiotics is increased by 10 times, the free radical scavenging rate is enhanced by 5 times, and the intestinal retention time can be prolonged by 6-12 h. In the DSS-induced murine colitis model, it significantly alleviated colon shortening, inhibited ROS overexpression, and promoted the repair and regeneration of the mucus layer. This dual-layer encapsulation approach for a single probiotic demonstrates a significant advancement in probiotic delivery technology, offering hope for a comprehensive approach to the treatment of colitis and potentially other gastrointestinal disorders.

Potential carcinogenic role of Reg IV in ulcerative colitis-associated colorectal neoplasia

Background

Early detection of ulcerative colitis-associated neoplasia (UC-N) remains a clinical challenge. Identification of molecular biomarkers for colorectal dysplasia and cancer may be extremely beneficial in early detection and managing cancer risk in long-standing ulcerative colitis (UC) patients.

Objective

The aim of this work is to investigate the role of Reg IV in comparison to P53 and KRAS in UC-associated dysplasia and colorectal cancer (CRC) in order to evaluate the potential use of Reg IV for dysplasia and cancer screening in UC patients.

Methods

The study was conducted on 5 groups each 20 colonic endoscopic samples: 1) Normal colonic mucosa, 2) Active UC without dysplasia/carcinoma, 3) UC-associated dysplasia, 4) UC-associated CRC (UC-CRC), 5) Sporadic CRC. All included cases were subjected to Reg IV mRNA expression analysis by quantitative reverse transcription polymerase chain reaction, and immunostaining for Reg IV, P53 and KRAS.

Results

Reg IV mRNA expression levels were found to be significantly higher in groups 3 and 4 (mean: 3.37 and 5.70, respectively). Reg IV immunostaining was highly expressed in groups 3 and 4 (mean: 45.80 and 62.35, respectively). While P53 and KRAS immunostaining was highly expressed in group 5 (mean: 64.57 and 62.90). Furthermore, Reg IV immunoexpression had shown a negative correlation with P53 and KRAS immunoexpression in groups 4 and 5.

Conclusion

Higher expression of Reg IV in patients with UC-dysplasia and UC-CRC versus KRAS and P53 expression in sporadic CRC, suggests a potential role of Reg IV in UC carcinogenesis pathway. This could advocate the use of Reg IV as a screening biomarker for UC-N among patients with long-standing UC as well as a promising targeted therapeutic strategy.

Hereditary Colorectal Cancer Syndromes and Inflammatory Bowel Diseases: Risk Management and Surveillance Strategies

Background and aims: Hereditary colorectal cancer syndromes (HCCS), including familial adenomatous polyposis (FAP) and Lynch syndrome (LS), are the two most important high-risk conditions for colorectal cancer (CRC). Inflammatory bowel disease (IBD) increases the risk by two to six times compared with that in the general population. The intersection of these two conditions has rarely been documented in literature. We aimed to summarize the prevalence, pathogenesis, and current evidence-based management of IBD and HCCS and the underlying molecular mechanisms of accelerated carcinogenesis due to combined inflammation and genetic predisposition. Methods: PubMed and Scopus were searched until June 2024 to identify relevant studies investigating the epidemiology, pathogenesis, and management of IBD and coexisting hereditary CRC syndromes. Results: Co-occurrence of IBD and hereditary CRC syndromes is exceptionally uncommon. Individuals with LS and IBD tend to develop CRC at a younger age than those without IBD, with patients with ulcerative colitis facing particularly elevated risks. The interaction between mismatch deficiency and chronic inflammation requires further investigation.

Inflammatory response in gastrointestinal cancers: Overview of six transmembrane epithelial antigens of the prostate in pathophysiology and clinical implications

Chronic inflammation is known to increase the risk of gastrointestinal cancers (GICs), the common solid tumors worldwide. Precancerous lesions, such as chronic atrophic inflammation and ulcers, are related to inflammatory responses in vivo and likely to occur in hyperplasia and tumorigenesis. Unfortunately, due to the lack of effective therapeutic targets, the prognosis of patients with GICs is still unsatisfactory. Interestingly, it is found that six transmembrane epithelial antigens of the prostate (STEAPs), a group of metal reductases, are significantly associated with the progression of malignancies, playing a crucial role in systemic metabolic homeostasis and inflammatory responses. The structure and functions of STEAPs suggest that they are closely related to intracellular oxidative stress, responding to inflammatory reactions. Under the imbalance status of abnormal oxidative stress, STEAP members are involved in cell transformation and the development of GICs by inhibiting or activating inflammatory process. This review focuses on STEAPs in GICs along with exploring their potential molecular regulatory mechanisms, with an aim to provide a theoretical basis for diagnosis and treatment strategies for patients suffering from these types of cancers.

Exploring the theranostic potentials of miRNA and epigenetic networks in autoimmune diseases: A comprehensive review

BACKGROUND

Autoimmune diseases (AD) are severe pathophysiological ailments that are stimulated by an exaggerated immunogenic response towards self-antigens, which can cause systemic or site-specific organ damage. An array of complex genetic and epigenetic facets majorly contributes to the progression of AD, thus providing significant insight into the regulatory mechanism of microRNA (miRNA). miRNAs are short, non-coding RNAs that have been identified as essential contributors to the post-transcriptional regulation of host genome expression and as crucial regulators of a myriad of biological processes such as immune homeostasis, T helper cell differentiation, central and peripheral tolerance, and immune cell development.

AIMS

This article tends to deliberate and conceptualize the brief pathogenesis and pertinent epigenetic regulatory mechanism as well as miRNA networks majorly affecting five different ADs namely rheumatoid arthritis (RA), type 1 diabetes, multiple sclerosis (MS), systemic lupus erythematosus (SLE) and inflammatory bowel disorder (IBD) thereby providing novel miRNA-based theranostic interventions.

RESULTS & DISCUSSION

Pertaining to the differential expression of miRNA attributed in target tissues and cellular bodies of innate and adaptive immunity, a paradigm of scientific expeditions suggests an optimistic correlation between immunogenic dysfunction and miRNA alterations.

CONCLUSION

Therefore, it is not astonishing that dysregulations in miRNA expression patterns are now recognized in a wide spectrum of disorders, establishing themselves as potential biomarkers and therapeutic targets. Owing to its theranostic potencies, miRNA targets have been widely utilized in the development of biosensors and other therapeutic molecules originating from the same.

Inflammatory Bowel Diseases: An Updated Overview on the Heat Shock Protein Involvement

Inflammatory bowel diseases (IBDs) represent chronic idiopathic disorders, including Crohn's disease (CD) and ulcerative colitis (UC), in which one of the trigger factors is represented by aberrant immune interactions between the intestinal epithelium and the intestinal microbiota. The involvement of heat shock proteins (HSPs) as etiological and pathogenetic factors is becoming of increasing interest. HSPs were found to be differentially expressed in the intestinal tissues and sera of patients with CD and UC. It has been shown that HSPs can play a dual role in the disease, depending on the stage of progression. They can support the inflammatory and fibrosis process, but they can also act as protective factors during disease progression or before the onset of one of the worst complications of IBD, colorectal cancer. Furthermore, HSPs are able to mediate the interaction between the intestinal microbiota and intestinal epithelial cells. In this work, we discuss the involvement of HSPs in IBD considering their genetic, epigenetic, immune and molecular roles, referring to the most recent works present in the literature. With our review, we want to shed light on the importance of further exploring the role of HSPs, or even better, the role of the molecular chaperone system (CS), in IBD: various molecules of the CS including HSPs may have diagnostic, prognostic and therapeutic potential, promoting the creation of new drugs that could overcome the side-effects of the therapies currently used.