Alicaforsen in the treatment of pouchitis

Identification of Differentially Expressed Genes and miRNAs for Ulcerative Colitis Using Bioinformatics Analysis

Introduction: Ulcerative colitis (UC) is a chronic inflammatory disease of the intestine whose cause and underlying mechanisms are not fully understood. The aim of this study was to use bioinformatics analysis to identify differentially expressed genes (DEGs) with diagnostic and therapeutic potential in UC.

Materials and methods: Three UC datasets (GSE179285, GSE75214, GSE48958) were downloaded from the Gene Expression Omnibus (GEO) database. DEGs between normal and UC tissues were identified using the GEO2R online tool. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of the DEGs were performed using Metascape. Protein-protein interaction network (PPI) analysis and visualization using STRING and Cytoscape. Finally, the miRNA gene regulatory network was constructed by Cytoscape to predict potential microRNAs (miRNAs) associated with DEGs.

Results: A total of 446 DEGs were identified, consisting of 309 upregulated genes and 137 downregulated genes. The enriched functions and pathways of the DEGs include extracellular matrix, regulation of cell adhesion, inflammatory response, response to cytokine, monocarboxylic acid metabolic process, response to toxic substance. The analysis of KEGG pathway indicates that the DEGs were significantly enriched in Complement and coagulation cascades, Amoebiasis, TNF signaling pathway, bile secretion, and Mineral absorption. Combining the results of the PPI network and CytoHubba, 9 hub genes including CXCL8, ICAM1, CXCR4, CD44, IL1B, MMP9, SPP1, TIMP1, and HIF1A were selected. Based on the DEG-miRNAs network construction, 7 miRNAs including miR-335-5p, mir-204-5p, miR-93-5p, miR106a-5p, miR-21-5p, miR-146a-5p, and miR-155-5p were identified as potential critical miRNAs.

Conclusion: In summary, we identified DEGs that may be involved in the progression or occurrence of UC. A total of 446 DEGs,9 hub genes and 7 miRNAs were identified, which may be considered as biomarkers of UC. Further studies, however, are needed to elucidate the biological functions of these genes in UC.

Medical treatment of pouchitis: a guide for the clinician

Pouchitis is the most common complication in patients who have undergone restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA). Up to 81% of IPAA patients experience pouchitis, with 40% of patients presenting within the first year of surgery. Common risk factors include genetic mutations, extensive colitis, rheumatologic disorders, and primary sclerosing cholangitis. Currently, there are no medications with approved indications for pouchitis. As such, the conventional treatment of pouchitis is entirely off-label. This paper is intended to be a practical and up-to-date review of available therapies used for the management of pouchitis. The mainstay of treatment for acute pouchitis remains antibiotics, but newer therapeutics have also shown promise in the treatment of chronic pouchitis. Common lifestyle considerations that may play a role in pouchitis are also reviewed.

PLAIN LANGUAGE SUMMARY

Medical treatment of pouchitis: a guide for the clinician The ileal pouch-anal anastomosis ("pouch") is the most common way patients who require surgery to remove their colon are able to avoid a permanent ileostomy ("ostomy"). This pouch, created from the small intestines, serves as a reservoir to hold stool. The most common complication after pouch surgery is pouchitis. Pouchitis symptoms include more frequent bowel movements, urgency to defecate, blood in the stool, incontinence, and abdominal pain. This paper is intended to be a practical review of available therapies including medications and lifestyle changes that can be considered for the management of acute pouchitis, chronic pouchitis, and cuffitis.

Chronic Antibiotic-Refractory Pouchitis: Management Challenges

Background

Pouchitis is the most common long-term complication in patients with ulcerative colitis who underwent restorative proctocolectomy with ileal pouch-anal anastomosis. The incidence of acute pouchitis is 20% after 1 year and up to 40% after 5 years. Chronic antibiotic-refractory pouchitis develops in approximately 10% of patients.

Aim

To present a narrative review of published literature regarding the management of chronic antibiotic-refractory pouchitis.

Methods

Current relevant literature was summarized and critically evaluated.

Results

Clear definitions should be used to classify pouchitis into acute versus chronic, and responsive versus dependent versus refractory to antibiotics. Before treatment is started for chronic antibiotic-refractory pouchitis, secondary causes should be ruled out. There is a need for validated scoring systems to measure the severity of the disease. Because chronic antibiotic-refractory pouchitis is a rare condition, only small studies with often a poor study design have been performed. Treatments with antibiotics, aminosalicylates, steroids, immunomodulators and biologics have shown to be effective and safe for chronic antibiotic-refractory pouchitis. Also, treatments with AST-120, hyperbaric oxygen therapy, tacrolimus enemas, and granulocyte and monocyte apheresis suggested some efficacy.

Conclusion

The available data are weak but suggest that therapeutic options for chronic antibiotic-refractory pouchitis are similar to the treatment strategies for inflammatory bowel diseases. However, randomized controlled trials are warranted to further identify the best treatment options in this patient population.

Antisense technology: an overview and prospectus

Antisense technology is now beginning to deliver on its promise to treat diseases by targeting RNA. Nine single-stranded antisense oligonucleotide (ASO) drugs representing four chemical classes, two mechanisms of action and four routes of administration have been approved for commercial use, including the first RNA-targeted drug to be a major commercial success, nusinersen. Although all the approved drugs are for use in patients with rare diseases, many of the ASOs in late- and middle-stage clinical development are intended to treat patients with very common diseases. ASOs in development are showing substantial improvements in potency and performance based on advances in medicinal chemistry, understanding of molecular mechanisms and targeted delivery. Moreover, the ASOs in development include additional mechanisms of action and routes of administration such as aerosol and oral formulations. Here, we describe the key technological advances that have enabled this progress and discuss recent clinical trials that illustrate the impact of these advances on the performance of ASOs in a wide range of therapeutic applications. We also consider strategic issues such as target selection and provide perspectives on the future of the field.

Antisense technology: A review

Antisense technology is beginning to deliver on the broad promise of the technology. Ten RNA-targeted drugs including eight single-strand antisense drugs (ASOs) and two double-strand ASOs (siRNAs) have now been approved for commercial use, and the ASOs in phase 2/3 trials are innovative, delivered by multiple routes of administration and focused on both rare and common diseases. In fact, two ASOs are used in cardiovascular outcome studies and several others in very large trials. Interest in the technology continues to grow, and the field has been subject to a significant number of reviews. In this review, we focus on the molecular events that result in the effects observed and use recent clinical results involving several different ASOs to exemplify specific molecular mechanisms and specific issues. We conclude with the prospective on the technology.

Antisense drug discovery and development technology considered in a pharmacological context

When coined, the term "antisense" included oligonucleotides of any structure, with any chemical modification and designed to work through any post-RNA hybridization mechanism. However, in practice the term "antisense" has been used to describe single stranded oligonucleotides (ss ASOs) designed to hybridize to RNAswhile the term "siRNA" has come to mean double stranded oligonucleotides designed to activate Ago2. However, the two approaches share many common features. The medicinal chemistry developed for ASOs greatly facilitated the development of siRNA technology and remains the chemical basis for both approaches. Many of challenges faced and solutions achieved share many common features. In fact, because ss ASOs can be designed to activate Ago2, the two approaches intersect at this remarkably important protein. There are also meaningful differences. The pharmacokinetic properties are quite different and thus potential routes of delivery differ. ASOs may be designedto use a variety of post-RNA binding mechanismswhile siRNAs depend solely on the robust activity of Ago2. However, siRNAs and ASOs are both used for therapeutic purposes and both must be and can be understood in a pharmacological context. Thus, the goals of this review are to put ASOs in pharmacological context and compare their behavior as pharmacological agents to the those of siRNAs.

Controlling leukocyte trafficking in IBD

Inflammatory bowel disease (IBD) is characterized by the accumulation of immune cells, myeloid cells and lymphocytes in the inflamed intestine. The presence and persistence of these cells, together with the production of pro-inflammatory mediators, perpetuate intestinal inflammation in both ulcerative colitis and Crohn's disease. Thus, blockade of leukocyte migration to the intestine is a main strategy used to control the disease and alleviate symptoms. Vedolizumab is the only anti-integrin drug approved for the treatment of IBD but several other drugs also targeting integrins, chemokines or receptors involved in leukocyte intestinal trafficking are under development and investigated for their efficacy and safety in IBD. The challenge now is to better understand the specific mechanism of action underlying each drug and to identify biomarkers that would guide drug selection in the individual patient.

Microbiome characterization and re-design by biologic agents for inflammatory bowel disease insights

The therapeutic effect of inflammatory bowel disease has improved in the past decades, but most of patients cannot tolerate, do not respond to drugs, or relapse after treating with conventional therapy. Therefore, new and more effective treatment methods are still needed in treatment of IBD. In this review, we will discuss the relevant mechanisms and the latest research progress of biologics (anti-TNF treatments, interleukin inhibitors, integrin inhibitors, antisense oligonucleotide, and JAK inhibitors) for IBD, focus on the efficacy and safety of drugs for moderate-to-severe IBD, and summarize the clinical status and future development direction of biologics in IBD.