Immune Checkpoint Inhibitor-Associated Colitis: From Mechanism to Management

Peptic ulcer induced by immune checkpoint inhibitors successfully treated with glucocorticoids: A report of three cases and a literature review

In recent decades, immune checkpoint inhibitors (ICIs) have emerged as safer and less disruptive alternatives to conventional chemotherapy and radiotherapy for certain patients with tumours. ICIs serve a synergistic role alongside conventional therapies by manipulating the immune system to recognise and target tumour cells. However, excessive activation of the immune system can lead to immune-related adverse events including pneumonia, myocarditis and colitis, which pose serious and even fatal risks. In the present case series, three patients with a thoracic tumour with an ICI-induced peptic ulcer triggered by programmed cell death protein 1 antibodies (diagnosed by gastrointestinal endoscopy) are presented. These cases were successfully treated with corticosteroids. The diagnostic and treatment processes undertaken for these patients underscore the requirement to comprehensively understand the mechanism of ICI-induced peptic ulcer. Moreover, the relevant literature was also reviewed in the present study.

Abscopal effect: from a rare phenomenon to a new frontier in cancer therapy

Radiotherapy (RT) controls local lesions, meantime it has the capability to induce systemic response to inhibit distant, metastatic, non-radiated tumors, which is referred to as the "abscopal effect". It is widely recognized that radiotherapy can stimulate systemic immune response. This provides a compelling theoretical basis for the combination of immune therapy combined with radiotherapy(iRT). Indeed, this phenomenon has also been observed in clinical treatment, bringing significant clinical benefits to patients, and a series of basic studies are underway to amplify this effect. However, the molecular mechanisms of immune response induced by RT, determination of the optimal treatment regimen for iRT, and how to amplify the abscopal effect. In order to amplify and utilize this effect in clinical management, these key issues require to be well addressed; In this review, we comprehensively summarize the growing consensus and emphasize the emerging limitations of enhancing the abscopal effect with radiotherapy or immunotherapy. Finally, we discuss the prospects and barriers to the current clinical translational applications.

Immune checkpoint inhibitor colitis, a rising issue in targeted cancer therapy era: A literature review

Research advances in the oncology treatment field have led to the widespread use of immunotherapy. The usage of immune checkpoint inhibitor (ICI) has improved the survival of cancer patients with metastases. This has also led to the rapidly expanding indications for ICI use. However, ICI usage may lead to toxicity, which may be immune-related, in different organ-specific targets. The immune-related adverse events (irAEs) of ICI may lead to increased morbidity, decreased quality of life, and early termination of ICI. The clinical manifestations of irAEs in the gastrointestinal system are variable, ranging from self-limited to life-threatening or fatal events. In this review article, we would like to focus on discussing ICI-induced colitis, which is one of the most common ICI irAEs in the gastrointestinal tract.

Targeting novel regulated cell death: Ferroptosis, pyroptosis and necroptosis in anti-PD-1/PD-L1 cancer immunotherapy

Chemotherapy, radiotherapy, and immunotherapy represent key tumour treatment strategies. Notably, immune checkpoint inhibitors (ICIs), particularly anti-programmed cell death 1 (PD1) and anti-programmed cell death ligand 1 (PD-L1), have shown clinical efficacy in clinical tumour immunotherapy. However, the limited effectiveness of ICIs is evident due to many cancers exhibiting poor responses to this treatment. An emerging avenue involves triggering non-apoptotic regulated cell death (RCD), a significant mechanism driving cancer cell death in diverse cancer treatments. Recent research demonstrates that combining RCD inducers with ICIs significantly enhances their antitumor efficacy across various cancer types. The use of anti-PD-1/PD-L1 immunotherapy activates CD8+ T cells, prompting the initiation of novel RCD forms, such as ferroptosis, pyroptosis, and necroptosis. However, the functions and mechanisms of non-apoptotic RCD in anti-PD1/PD-L1 therapy remain insufficiently explored. This review summarises the emerging roles of ferroptosis, pyroptosis, and necroptosis in anti-PD1/PD-L1 immunotherapy. It emphasises the synergy between nanomaterials and PD-1/PD-L1 inhibitors to induce non-apoptotic RCD in different cancer types. Furthermore, targeting cell death signalling pathways in combination with anti-PD1/PD-L1 therapies holds promise as a prospective immunotherapy strategy for tumour treatment.

Obinutuzumab-Induced Inflammatory Bowel Disease-Like Pancolitis: A First Case Report

Introduction

Obinutuzumab is a type II anti-CD20 monoclonal antibody associated with a higher rate of toxicity when compared to rituximab. Gastrointestinal side-effects have been reported but data is still sparse.

Case Presentation

A 47-year-old female with medical history of stage IV follicular non-Hodgkin lymphoma under chemotherapy presented with chronic bloody diarrhea and iron deficiency anemia. Endoscopic and histologic features resembled inflammatory bowel disease (IBD), imposing a thorough differential diagnosis. The diagnosis of obinutuzumab-induced pancolitis was made and the drug was suspended with subsequent clinical improvement.

Conclusion

This is the first case report of obinutuzumab-induced pancolitis. The challenging differential diagnosis of IBD required a multidisciplinary approach with subsequent outcome and management implications.

Multidisciplinary management of ulcerative colitis complicated by immune checkpoint inhibitor-associated colitis with life-threatening gastrointestinal hemorrhage: A case report

BACKGROUND

Programmed cell death 1 (PD-1) inhibitors are immune checkpoint inhibitors (ICI) that have demonstrated significant efficacy in treating various advanced malignant tumors. While most patients tolerate treatment well, several adverse drug reactions, such as fatigue, myelosuppression, and ICI-associated colitis, have been reported.

CASE SUMMARY

This case involved a 57-year-old male patient with ulcerative colitis complicated by hepatocarcinoma who underwent treatment with tirelizumab (a PD-1 inhibitor) for six months. The treatment led to repeated life-threatening lower gastrointestinal hemorrhage. The patient received infliximab, vedolizumab, and other salvage procedures but ultimately required subtotal colectomy due to uncontrollable massive lower gastrointestinal bleeding. Currently, postoperative gastrointestinal bleeding has stopped, the patient's stool has turned yellow, and his full blood cell count has returned to normal.

CONCLUSION

This case highlights the necessity of early identification, timely and adequate treatment of ICI-related colitis, and rapid escalation to achieve the goal of improving prognosis.

Immune-related colitis presenting with constipation

Anticancer immunotherapies modulate the body's immune system to recognise and eradicate cancerous cells. However, stimulation of the body's immune system can also lead to a number of adverse effects when those immune cells target non-cancerous cells in the form of autoimmunity. One relatively common example of this off-target action is colitis.We present three patients who presented atypically with colitis, consequently, leading to a delayed diagnosis. These cases highlight the diverse ways a relatively common immune-related adverse event can present.

Clinical characteristics and prognosis of pancreatitis associated with immune checkpoint inhibitors

BACKGROUND AND OBJECTIVE

Immune checkpoint inhibitors (ICIs) have shown remarkable efficacy against various cancers in clinical practice. However, ICIs can cause immune checkpoint inhibitor-associated pancreatic injury, often leading to drug withdrawal, and then patients must go to specialized treatment. The patients, their primary tumors are sensitive to ICIs therapy, may experience treatment delays due to such adverse reactions. Therefore, there is a need for systematic clinical researches on immune-related pancreatic toxicity to provide a clinical basis for its prevention and treatment.

METHODS

This study involved the collection of data from patients treated with ICIs and addressed pancreatic injury with preemptive treatment before continuing ICIs therapy. Then, we also statistically analyzed the incidence of pancreatic injury in patients with different courses and combined treatment, and the success rate of rechallenge treatment.

RESULTS

The study included 62 patients, with 33.9% (21/62) experiencing varying degrees of pancreatic injury. Patients with pancreatic injury, 10 cases evolved into pancreatitis, representing 47.6% (10/21) in the pancreatic injury subgroup and 16.1% (10/62) of the total patient cohort. Preemptive treatment was administered to 47.6% (10/21) of patients with pancreatitis, the effective rate was 100%. Among these patients, 70% (7/10) underwent successful rechallenge with ICIs. The occurrence of pancreatic injury was positively correlated with the treatment duration (P < 0.05) but showed no significant correlation with combination therapies (P > 0.05).

CONCLUSION

The likelihood of pancreatic injury increased with longer treatment durations with ICIs; no significant association was found between the incidence of ICIs-related pancreatic damage and combination therapies. Preemptive treatment for immune-related pancreatitis is feasible, allowing some patients to successfully undergo rechallenge with ICIs therapy.

Outcome of an Accelerated Treatment Algorithm for Patients Developing Diarrhea as a Complication of Ipilimumab-Based Cancer Immunotherapy in a Community Practice

Immune-mediated diarrhea represents a serious complication of checkpoint inhibitor therapy, especially following ipilimumab-based treatment. Efficient diagnosis and control of diarrhea remains an ongoing challenge. We developed an accelerated management paradigm for patients with ipilimumab-induced diarrhea. Patients who developed significant diarrhea (>five loose stools/day) were presumed to be developing immune colitis. Therapy was interrupted and patients were treated with a methylprednisolone dose pack. If diarrhea was not completely resolved, high-dose steroids and infliximab were promptly added. Only non-responding patients underwent further evaluation for infection or other causes of diarrhea. A total of 242 patients were treated with ipilimumab-based regimens. Forty-six developed significant diarrhea (19%) and thirty-four (74.4%) had a rapid resolution of diarrhea following glucocorticosteroid and infliximab treatment. The median time to resolution of diarrhea was only 8.5 ± 16.4 days. Accelerated treatment for presumed immune-mediated diarrhea resulted in the rapid control of symptoms in the majority of patients. There were no intestinal complications or deaths. Immunosuppressive therapy for diarrhea did not appear to decrease the remission rate or survival. After the control of diarrhea, most patients were able to continue their planned immunotherapy. Further testing in 11/46 patients with unresponsive diarrhea revealed additional diagnoses, allowing their treatment to be adjusted.

Focus on Immune Checkpoint Inhibitors-related Intestinal Inflammation: From Pathogenesis to Therapeutical Approach

Recently, antitumor immunotherapies have witnessed a breakthrough with the emergence of immune checkpoint inhibitors (ICIs) including programmed cell death-1 (PD-1), programmed cell death-ligand 1 (PD-L1), and cytotoxic T lymphocyte antigen 4 (CTLA-4) inhibitors. Unfortunately, the use of ICIs has also led to the advent of a novel class of adverse events that differ from those of classic chemotherapeutics and are more reminiscent of autoimmune diseases, the immune-related adverse events (IRAEs). Herein, we performed an insight of the main IRAEs associated with ICIs, focusing on gastroenterological IRAEs and specifically on checkpoint inhibitor colitis, which represents the most widely reported IRAE to date. We comprehensively dissected the current evidence regarding pathogenesis, diagnosis, and management of ICIs-induced colitis, touching upon also on innovative therapies.

Prognostic Value of Inflammatory Bowel Disease-associated Biomarkers in Patients With Immune Checkpoint Inhibitor Enterocolitis: A Retrospective Cohort Study

In the emerging field of immune checkpoint inhibitor enterocolitis, biomarkers to predict disease course are lacking. Select genetic polymorphisms (ATG16L1T300A) and serum amyloid A warrant further study as potential biomarkers associated with severe ICI enterocolitis.

Group 3 innate lymphoid cells in intestinal health and disease

The gastrointestinal tract is an immunologically rich organ, containing complex cell networks and dense lymphoid structures that safeguard this large absorptive barrier from pathogens, contribute to tissue physiology and support mucosal healing. Simultaneously, the immune system must remain tolerant to innocuous dietary antigens and trillions of normally beneficial microorganisms colonizing the intestine. Indeed, a dysfunctional immune response in the intestine underlies the pathogenesis of numerous local and systemic diseases, including inflammatory bowel disease, food allergy, chronic enteric infections or cancers. Here, we discuss group 3 innate lymphoid cells (ILC3s), which have emerged as orchestrators of tissue physiology, immunity, inflammation, tolerance and malignancy in the gastrointestinal tract. ILC3s are abundant in the developing and healthy intestine but their numbers or function are altered during chronic disease and cancer. The latest studies provide new insights into the mechanisms by which ILC3s fundamentally shape intestinal homeostasis or disease pathophysiology, and often this functional dichotomy depends on context and complex interactions with other cell types or microorganisms. Finally, we consider how this knowledge could be harnessed to improve current treatments or provoke new opportunities for therapeutic intervention to promote gut health.

Follow-up biopsies in gastrointestinal immune checkpoint inhibitor toxicity may show markedly different inflammatory patterns than initial injury

Colitis is a common manifestation of immune checkpoint inhibitor (ICI) toxicity and can present with varied histologic patterns of inflammation, some of which have been shown to be associated with specific ICI drug types. Although the histologic features of ICI colitis seen at the time of diagnosis have been described, there have been few reports following these patients over time. We evaluated initial and follow-up biopsies in 30 patients with ICI colitis and found that 37% of patients developed a different pattern of injury on follow-up biopsy compared to the initial biopsy. Patients with a different inflammatory pattern were more likely to have restarted ICI therapy before their follow-up biopsy (64%) compared to those without a change in inflammatory pattern (11%; P < 0.01). The majority of these patients had changed ICI drug types (86%). Additionally, many cases changed to an inflammatory bowel disease (IBD)-like pattern (36%), raising a question of de novo IBD. However, all of our patients with an IBD-like pattern experienced sustained resolution of symptoms without steroids or other immunosuppressive medications following discontinuation of ICI therapy, consistent with a diagnosis of ICI toxicity. Our findings suggest that follow-up biopsies in patients with ICI colitis may show a different histology and that this does not necessarily warrant a change in the histologic diagnosis to another disease.

DNMT3A promotes glioma growth and malignancy via TNF-α/NF-κB signaling pathway

Background

DNMT3A is the main molecule responsible for DNA methylation in cells. DNMT3A affects the progression of inflammation, degenerative diseases, and malignant tumors, and exhibits significant aberrantly expression in tumor tissues.

Methods

Transcriptome data and relevant clinical information were downloaded from The Cancer Genome Atlas (TCGA), Chinese Glioma Genome Atlas (CGGA), and Gene Expression Omnibus (GEO) datasets. Differential expression analysis and prognostic analysis were conducted based on above statistics. We constructed a clinical prognostic model and identified DNMT3A as an independent prognostic factor to accurately predict patient prognosis. Differential gene enrichment analysis revealed that DNMT3A affects the progression of glioma through multiple pathways, among which the tumor necrosis factor-α (TNF-α)/nuclear factor-kappa B (NF-κB) pathway shows a strong correlation. Immunological analysis also revealed a certain correlation between DNMT3A and tumor immunity. We demonstrated through gene editing that DNMT3A can affect the release of TNF-α in cells, thereby affecting the progression of glioma. Functional experiments have also demonstrated that DNMT3A plays a crucial role in tumors.

Results

RNA-sequencing and survival analyses of lower-grade glioma (LGG) patients in TCGA, CGGA, and GEO cohorts showed that high DNMT3A expression correlated with poor prognosis of LGG patients. Univariate and multivariate Cox regression analyses showed that DNMT3A expression was an independent prognostic indicator in LGG. The prognosis prediction nomogram with age, World Health Organization (WHO) grading, and DNMT3A expression showed reliable performance in predicting the 1-, 3-, and 5-year overall survival (OS) of LGG patients. Functional enrichment analysis, gene set enrichment analysis (GSEA), and ESTIMATE algorithm analyses showed that DNMT3A expression was associated with the tumor infiltration of immune cells and predicted response to immunotherapy in two immunotherapy cohorts of pan-cancer patients. Furthermore, short hairpin RNA (shRNA)-mediated knockdown of DNMT3A in the LGG cell lines suppressed proliferation, migration, and invasion of LGG cells by downregulating the TNF-α/NF-κB signaling pathway.

Conclusions

Our data showed that DNMT3A was a potential prognostic biomarker in glioma. DNMT3A promoted proliferation and malignancy of LGG cells through the TNF-α/NF-κB signaling pathway. DNMT3A is a promising therapeutic target for treating patients with LGG.

Cordyceps sinensis relieves non-small cell lung cancer by inhibiting the MAPK pathway

OBJECTIVE

To determine the pharmacodynamic mechanism underlying Cordyceps sinensis relief in a murine model of non-small cell lung cancer (NSCLC).

METHODS

We created a murine model of NSCLC and studied the potential molecular mechanism by which C. sinensis relieved NSCLC using a combination of transcriptomics, proteomics, and experimental validation.

RESULTS

C. sinensis markedly suppressed the fluorescence values in mice with NSCLC, improved the pathologic morphology of lung tissue, ameliorated inflammatory cytokines (tumor necrosis factor-alpha, interleukin-6, interleukin-10, and the oxidative stress indicators superoxide dismutase, malondialdehyde, and glutathione peroxidase). Transcriptomics results showed that the therapeutic effect of C. sinensis was primarily involved in the differentiation and activation of T cells. Based on the proteomic results, C. sinensis likely exerted a protective effect by recruiting immune cells and suppressing tumor cell proliferation via the MAPK pathway. Finally, the experimental validation results indicated that C. sinensis significantly decreased the VEGF and Ki67 expression, downregulated RhoA, Raf-1, and c-fos expression, which are related to cell migration and invasion, increased the serum concentration of hematopoietic factors (EPO and GM-CSF), and improved the percentage of immune cells (natural killer cells, dendritic cells, and CD4+ and CD8+ lymphocytes), which enhanced immune function.

CONCLUSIONS

Based on our preclinical study, C. sinensis was shown to exert a protective effect on NSCLC, primarily by inhibiting the MAPK pathway.

New strategies in the diagnosis and treatment of immune-checkpoint inhibitor-mediated colitis

Immune-checkpoint inhibitor-mediated colitis (IMC) is an increasingly recognized adverse event in cancer immunotherapy, particularly associated with immune checkpoint inhibitors (ICIs) such as anti-cytotoxic T-lymphocyte antigen-4 and anti-programmed cell death protein-1 antibodies. As this revolutionary immunotherapy gains prominence in cancer treatment, understanding, diagnosing, and effectively managing IMC becomes paramount. IMC represents a unique challenge due to its immune-mediated nature and potential for severe complications. However, a precise picture of IMC pathophysiology is currently unavailable. Therefore, we aimed to summarize the existing data while acknowledging the need for further research. This comprehensive review explores the mechanisms underlying ICIs, gastrointestinal adverse effects, and, in particular, IMC's incidence, prevalence, and features. Our review also emphasizes the importance of recognizing IMC's distinct clinical and histopathological features to differentiate it from other forms of colitis. Furthermore, this paper highlights the urgent need for evolving diagnostic methods, therapeutic strategies, and a multidisciplinary approach to effectively manage IMC.

Post-transplant Inflammatory Bowel Disease Associated with Donor-Derived TIM-3 Deficiency

Inflammatory bowel disease (IBD) occurring following allogeneic stem cell transplantation (aSCT) is a very rare condition. The underlying pathogenesis needs to be better defined. There is currently no systematic effort to exclude loss- or gain-of-function mutations in immune-related genes in stem cell donors. This is despite the fact that more than 100 inborn errors of immunity may cause or contribute to IBD. We have molecularly characterized a patient who developed fulminant inflammatory bowel disease following aSCT with stable 100% donor-derived hematopoiesis. A pathogenic c.A291G; p.I97M HAVCR2 mutation encoding the immune checkpoint protein TIM-3 was identified in the patient's blood-derived DNA, while being absent in DNA derived from the skin. TIM-3 expression was much decreased in the patient's serum, and in vitro-activated patient-derived T cells expressed reduced TIM-3 levels. In contrast, T cell-intrinsic CD25 expression and production of inflammatory cytokines were preserved. TIM-3 expression was barely detectable in the immune cells of the patient's intestinal mucosa, while being detected unambiguously in the inflamed and non-inflamed colon from unrelated individuals. In conclusion, we report the first case of acquired, "transplanted" insufficiency of the regulatory TIM-3 checkpoint linked to post-aSCT IBD.

Clinical characteristics, diagnosis, treatment, and prognosis of nivolumab induced gastritis

Gastritis has recently been reported to be associated with nivolumab, and the clinical characteristics of nivolumab induced gastritis remain unclear. To explore the clinical characteristics of nivolumab induced gastritis, and to provide reference for the classification and treatment guidelines of immune checkpoint inhibitors -related gastritis. Case reports, case series, and clinical studies of nivolumab induced gastritis were retrospectively analyzed by searching the database from the establishment of the database until September 30, 2023. Forty-seven were included, with a median age of 57 years (range 16, 93). The median time of symptom onset was 6 months (range 0.5,36) and 6.5 cycles (range 2, 62). Nausea (29 cases, 61.7%), vomiting (29 cases, 61.7%), and epigastric pain (28 cases, 59.6%) were the most common complaints. Esophagogastroduodenoscopy mainly showed erythema (28 cases, 59.6%). Gastric mucosa biopsy showed epithelial inflammatory cell infiltration (22 cases, 46.8%) and apoptosis (15 cases, 31.9%). Most patients' symptoms and gastric mucosa improved or recovered after receiving systemic steroid and proton pump inhibitor therapy regardless of whether nivolumab was discontinued. Two patients died from gastritis related events. Gastritis should be considered as the cause of unexplained epigastric symptoms in the administration of nivolumab. Understanding the clinical features of nivolumab induced gastritis is very important for accurate diagnosis and timely management of these patients.

Sargramostim for Prophylactic Management of Gastrointestinal Immune-Related Adverse Events of Immune Checkpoint Inhibitor Therapy for Cancer

Immune checkpoint inhibitor (ICI) therapy improves outcomes in several cancers. Unfortunately, many patients experience grade 3-4 treatment-related adverse events, including gastrointestinal (GI) toxicities which are common. These GI immune-related adverse events (irAEs) induced by ICIs present significant clinical challenges, require prompt intervention, and result in treatment delays or discontinuations. The treatment for these potentially severe and even fatal GI irAEs which include enterocolitis, severe diarrhea, and hepatitis may interfere with the anti-cancer approach. Sargramostim (glycosylated, yeast-derived, recombinant human GM-CSF) is an agent that has been used in clinical practice for more than 30 years with a well-recognized safety profile and has been studied in many therapeutic areas. The mechanism of action of sargramostim may treat moderate-to-severe GI irAEs without impairing the anti-cancer therapy. Some early data also suggest a potential survival benefit. Through the differentiation/maturation of monocytes, macrophages, and neutrophils and induction of anti-inflammatory T cell responses, GM-CSF aids in GI homeostasis, mucosal healing, and mucosal immunity. GM-CSF knockout mice are susceptible to severe colitis which was prevented with murine GM-CSF administration. For some patients with GI mucosa and immune cell function impairment, e.g., Crohn's disease, sargramostim reduces disease severity. In a prospective, randomized study (ECOG 1608), advanced melanoma patients had a reduction in grade 3-5 GI irAEs and less frequent colonic perforation in the sargramostim plus ipilimumab arm compared to ipilimumab alone. Sargramostim continues to be studied with ICIs for the prophylactic management of irAEs while also potentially providing a survival benefit.

Association between the Prognostic Nutritional Index and the Occurrence of Immune-Related Adverse Events

Immune-related adverse events (irAEs) affect all organs and are associated with various symptoms. The identification of biomarkers that can predict irAEs may be particularly clinically useful. This study aimed to investigate whether the prognostic nutritional index (PNI) before the initiation of immune checkpoint inhibitor (ICI) treatment can predict the occurrence of irAEs. We conducted a survey of 111 patients with cancer who were receiving ICI fixed-dose monotherapy at Saga University Hospital from the time each ICI became available until January 2020. We compared the PNI between the patients with and without irAE expression, established a cutoff value for PNI associated with the development of irAEs, and investigated the incidence of irAEs and progression-free survival (PFS) in groups divided by the cutoff value. Patients with irAEs had significantly higher PNI than did those without, and there was a significant association between PNI and irAEs after adjusting for potential factors (odds ratio, 1.12; 95% confidence interval, 1.03-1.21). In addition, PNI ≥44.2 was associated with a significantly higher incidence of irAEs (75.0% vs. 35.2%, p = 0.0001) and significantly longer PFS than PNI <44.2 (p = 0.025). In conclusion, pretreatment PNI may be associated with the risk of developing irAEs in patients with advanced recurrent solid tumors. When the PNI is ≥44.2, patient management is important for avoiding serious AEs because while the treatment may be effective, the occurrence of irAEs is a concern.

Fecal Microbiota Transplantation Alleviates Severe PD-1 Inhibitor-Associated Colitis Caused by Neoadjuvant Therapy for Esophageal Cancer: A Case Report

Surgical resection is the preferred treatment for early-stage esophageal cancer. But most patients with esophageal cancer are diagnosed at advanced stages, making them ineligible for surgery. Therefore, preoperative neoadjuvant therapy has been introduced to help them meet surgical requirements. However, this therapy has been associated with serious complications, such as diarrhea, preventing patients from surgery. During neoadjuvant therapy combined with chemoradiotherapy, a 58-year-old male patient with esophageal cancer was diagnosed with severe immune-related colitis, which seriously affected both cancer treatment and the patient's quality of life. Despite conventional antidiarrheal therapy, the patient remained refractory to treatment. However, after undergoing fecal microbiota transplantation, the frequency of diarrhea was significantly reduced. During e-colonoscopy, no significant ulcers were found in the sigmoid colon. Additionally, successful radical resection of esophageal cancer was performed, resulting in a favorable outcome for the patient. Regular follow-up appointments were scheduled to monitor the patient's progress. Fecal microbiota transplantation effectively relieved severe immune-related diarrhea in a patient undergoing neoadjuvant immunotherapy and chemoradiotherapy for esophageal cancer. This successful treatment ultimately enabled the patient to meet the surgical requirements for radical esophagectomy.

Immune checkpoint targeting antibodies hold promise for combinatorial cancer therapeutics

Through improving the immune system's ability to recognize and combat tumor cells as well as its receptivity to changes in the tumor microenvironment, immunotherapy has emerged as a highly successful addition to the treatment of cancer. However, tumor heterogeneity poses a significant challenge in cancer therapy as it can undermine the anti-tumor immune response through the manipulation of the extracellular matrix. To address these challenges and improve targeted therapies and combination treatments, the food and drug administration has approved several immunomodulatory antibodies to suppress immunological checkpoints. Combinatorial therapies necessitate the identification of multiple targets that regulate the intricate communication between immune cells, cytokines, chemokines, and cellular responses within the tumor microenvironment. The purpose of this study is to provide a comprehensive overview of the ongoing clinical trials involving immunomodulatory antibodies in various cancer types. It explores the potential of these antibodies to modulate the immune system and enhance anti-tumor responses. Additionally, it discusses the perspectives and prospects of immunomodulatory therapeutics in cancer treatment. Although immunotherapy shows great promise in cancer treatment, it is not exempt from side effects that can arise due to hyperactivity of the immune system. Therefore, understanding the intricate balance between immune activation and regulation is crucial for minimizing these adverse effects and optimizing treatment outcomes. This study aims to contribute to the growing body of knowledge surrounding immunomodulatory antibodies and their potential as effective therapeutic options in cancer treatment, ultimately paving the way for improved patient outcomes and deepening our perception of the intricate interactivity between the immune system and tumors.

Histopathologic Manifestations of Immune Checkpoint Inhibitor Therapy-Associated Gastrointestinal Tract Injury: A Practical Review

Immune checkpoint inhibitors have revolutionized the management of many advanced cancers by producing robust remissions. They mostly target two immune regulatory pathways: cytotoxic T lymphocyte antigen-4 and programmed death-1 or its ligand. However, a flip side is the immune-related adverse events (irAEs) commonly affecting the gastrointestinal (GI) tract that can cause treatment interruptions or discontinuation. This practical review discusses the clinical and histopathologic findings of irAEs encountered in the luminal GI tract, along with histopathologic differentials that can mimic varied inflammatory, infectious, or other medication-associated etiologies and the importance of clinico-pathologic correlation for an accurate diagnosis.

Treatment and outcomes of immune checkpoint inhibitors-associated colitis/diarrhea: A systematic review and meta-analysis

BACKGROUND

Immune checkpoint inhibitors (ICIs) have improved the outcomes of cancer patients. However, ICIs often lead to colitis/diarrhea. This study aimed to assess the treatment of ICIs-associated colitis/diarrhea and outcomes.

METHODS

PubMed, EMBASE, and Cochrane Library databases were searched for eligible studies which investigated the treatment and outcomes of colitis/diarrhea developing in patients who received ICIs. The pooled incidences of any-grade colitis/diarrhea, low-grade colitis, high-grade colitis, low-grade diarrhea, and high-grade diarrhea as well as the pooled rates of response to treatment, mortality, and ICIs permanent discontinuation and restarts in patients with ICIs-associated colitis/diarrhea were estimated using a random-effects model.

RESULTS

Among the 11,492 papers initially identified, 27 studies were included. The pooled incidences of any-grade colitis/diarrhea, low-grade colitis, high-grade colitis, low-grade diarrhea, and high-grade diarrhea were 17%, 3%, 17%, 13%, and 15%, respectively. The pooled rates of overall response, response to corticosteroid therapy, and response to biological agents were 88%, 50%, and 96%, respectively. The pooled short-term mortality in patients with ICIs-associated colitis/diarrhea was 2%. The pooled incidences of ICIs permanent discontinuation and restarts were 43% and 33%, respectively.

CONCLUSION

ICIs-associated colitis/diarrhea is common, but rarely lethal. Half of them are responsive to corticosteroid therapy. There is a fairly high rate of response to biological agents in steroid-refractory colitis/diarrhea patients.

Detection of IL12/23p40 via PET Visualizes Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), which includes both Crohn disease and ulcerative colitis, is a relapsing inflammatory disease of the gastrointestinal tract. Long-term chronic inflammatory conditions elevate the patient's risk of colorectal cancer (CRC). Currently, diagnosis requires endoscopy with biopsy. This procedure is invasive and requires a bowel-preparatory regimen, adding to patient burden. Interleukin 12 (IL12) and interleukin 23 (IL23) play key roles in inflammation, especially in the pathogenesis of IBD, and are established therapeutic targets. We propose that imaging of IL12/23 and its p40 subunit in IBD via immuno-PET potentially provides a new noninvasive diagnostic approach. Methods: Our aim was to investigate the potential of immuno-PET to image inflammation in a chemically induced mouse model of colitis using dextran sodium sulfate by targeting IL12/23p40 with a 89Zr-radiolabeled anti-IL12/23p40 antibody. Results: High uptake of the IL12/23p40 immuno-PET agent was exhibited by dextran sodium sulfate-administered mice, and this uptake correlated with increased IL12/23p40 present in the sera. Competitive binding studies confirmed the specificity of the radiotracer for IL12/23p40 in the gastrointestinal tract. Conclusion: These promising results demonstrate the utility of this radiotracer as an imaging biomarker of IBD. Moreover, IL12/23p40 immuno-PET can potentially guide treatment decisions for IBD management.

Immune-Related Adverse Events in Patients with Lung Cancer

PURPOSE OF REVIEW

Immune checkpoint inhibitors (ICI) have been widely adopted for the treatment of lung cancer since receiving first U.S Food and Drug Administration (FDA) approval in 2015. However, along with their use, the occurrence of immune-related adverse events (irAEs) has presented a challenge for both patients and oncology providers. In this manuscript, we reviewed the clinical trials that led to the approval of ICI by the FDA for the treatment of lung cancer between 2015 and 2023 to establish the frequency of irAEs in this patient population. Among the adverse events associated with ICI, we focused on the most common and relevant ones, including hypothyroidism, pneumonitis, diarrhea/colitis, skin rash, and hepatitis.

RECENT FINDINGS

We thoroughly examined the available literature, including society guidelines concerning these complications, to discuss various aspects such as their pathophysiology, epidemiology, diagnostic process, grading system, and clinical management. Additionally, we explored the association between irAEs and disease response. The management of irAEs is a crucial aspect of oncologic care, particularly due to their potential to cause severe and life-threatening clinical manifestations. We present each pertinent aspect in a concise and organized manner to provide guidance and assistance to oncology providers managing these patients in both outpatient and inpatient settings.

Targeting and cytotoxicity of chimeric antigen receptor T cells grafted with PD1 extramembrane domain

BACKGROUND

Immunosuppression induced by programmed cell death protein 1 (PD1) presents a significant constraint on the effectiveness of chimeric antigen receptor (CAR)-T therapy. The potential of combining PD1/PDL1 (Programmed cell death 1 ligand 1) axis blockade with CAR-T cell therapy is promising. However, developing a highly efficient and minimally toxic approach requires further exploration. Our attempt to devise a novel CAR structure capable of recognizing both tumor antigens and PDL1 encountered challenges since direct targeting of PDL1 resulted in systemic adverse effects.

METHODS

In this research, we innovatively engineered novel CARs by grafting the PD1 domain into a conventional second-generation (2G) CAR specifically targeting CD19. These CARs exist in two distinct forms: one with PD1 extramembrane domain (EMD) directly linked to a transmembrane domain (TMD), referred to as PE CAR, and the other with PD1 EMD connected to a TMD via a CD8 hinge domain (HD), known as PE8HT CAR. To evaluate their efficacy, we conducted comprehensive assessments of their cytotoxicity, cytokine release, and potential off-target effects both in vitro and in vivo using tumor models that overexpress CD19/PDL1.

RESULTS

The findings of our study indicate that PE CAR demonstrates enhanced cytotoxicity and reduced cytokine release specifically towards CD19 + PDL1 + tumor cells, without off-target effects to CD19-PDL1 + tumor cells, in contrast to 2G CAR-T cells. Additionally, PE CAR showed ameliorative differentiation, exhaustion, and apoptosis phenotypes as assessed by flow cytometry, RNA-sequencing, and metabolic parameter analysis, after encountering CD19 + PDL1 + tumor cells.

CONCLUSION

Our results revealed that CAR grafted with PD1 exhibits enhanced antitumor activity with lower cytokine release and no PD1-related off-target toxicity in tumor models that overexpress CD19 and PDL1. These findings suggest that our CAR design holds the potential for effectively addressing the PD1 signal.

Role of gut microbiome in cancer immunotherapy: from predictive biomarker to therapeutic target

Immunotherapy has emerged as an effective treatment for various types of cancers. Recent studies have highlighted a significant correlation between the gut microbiome and patients' response to immunotherapy. Several characteristics of the gut microbiome, such as community structures, taxonomic compositions, and molecular functions, have been identified as crucial biomarkers for predicting immunotherapy response and immune-related adverse events (irAEs). Unlike other -omics, the gut microbiome can serve as not only biomarkers but also potential targets for enhancing the efficacy of immunotherapy. Approaches for modulating the gut microbiome include probiotics/prebiotics supplementation, dietary interventions, fecal microbiota transplantation (FMT), and antibiotic administration. This review primarily focuses on elucidating the potential role of the gut microbiome in predicting the response to cancer immunotherapy and improving its efficacy. Notably, we explore reasons behind inconsistent findings observed in different studies, and highlight the underlying benefits of antibiotics in liver cancer immunotherapy.

Immune Checkpoint Inhibitor-Induced Hemorrhagic Gastritis

Immune checkpoint inhibitors (ICIs) have been increasingly used in the treatment of several malignancies and may target cytotoxic T-lymphocyte-associated antigen-4, programmed cell death-1, and programmed cell death ligand 1, which work on maintaining peripheral immune tolerance. ICIs inhibit these ligands causing an immune-enhancing effect, leading to a wide spectrum of complications from mild mucositis to life-threatening pneumonitis or hepatitis. These complications are collectively called immune-related adverse events. Their prevalence has increased with a rise in ICI use, with rare manifestations being reported in popular literature. We present a case of hemorrhagic gastritis due to the anti-programmed cell death-1 antibody, pembrolizumab.

Evaluation of appendectomy as a potential risk factor for immune checkpoint inhibitor-associated enterocolitis

Aims: The relationship between appendectomy and immune checkpoint inhibitor (ICI) enterocolitis was explored. Methods: Patients who began ICIs between July 2010 and September 2020 (n = 10,907) were included. The exposure group included patients with evidence of appendectomy prior to ICIs in operative notes (n = 380). The control group included patients with evidence of normal appendix in radiologic reports (n = 3602). ICI enterocolitis was defined as histopathologic evidence of colitis or enteritis attributed to ICIs. The association between appendectomy and ICI enterocolitis was characterized by multivariate logistic regression. Results: 248 patients (6.2%) developed ICI enterocolitis. The odds of ICI enterocolitis were similar among those with prior appendectomy and those without appendectomy (adjusted odds ratio: 0.82; 95% CI: 0.49-1.36; p = 0.449). Conclusion: No association was found between prior appendectomy and ICI enterocolitis.

Severe Immune-Mediated Colitis Induced by Checkpoint Inhibitors in an Adolescent With Lynch Syndrome

Lynch syndrome is a hereditary colorectal cancer caused by mutations in DNA mismatch repair genes. Immune checkpoint therapies have shown promise in treating Lynch syndrome-associated cancers but can lead to immune-related adverse events, such as colitis. In this report, we present a severe case of immune-mediated colitis (IMC) induced by checkpoint inhibitors in a young patient with Lynch syndrome. This 20-year-old male with Lynch syndrome and a history of glioblastoma underwent dual checkpoint therapy, after initial treatment with systemic steroids. Despite this, his condition worsened, resulting in complications, such as toxic megacolon and small bowel obstruction. He was subjected to various treatments, including infliximab and vedolizumab, but ultimately required total abdominal colectomy with J-pouch creation. This case highlights the challenges of managing severe IMC in patients with Lynch syndrome. The patient's suboptimal response to standard treatments and the development of complications emphasizes the need for a better understanding and alternative therapeutic options for IMC. This case also calls into question whether a subset of patients with IMC should be "treated to target," even though the current standard of care for IMC is guided by symptom response, and if so, further research is necessary to identify potential therapeutic targets. Further research is also required to understand the mechanisms of IMC and develop effective treatment strategies tailored to patients with Lynch syndrome and immune-related adverse events.

Checkpoint Inhibitor-Induced Colitis: From Pathogenesis to Management

The advent of immunotherapy, specifically of immune checkpoint inhibitors (ICIs), for the treatment of solid tumors has deeply transformed therapeutic algorithms in medical oncology. Approximately one-third of patients treated with ICIs may de velop immune-related adverse events, and the gastrointestinal tract is often affected by different grades of mucosal inflammation. Checkpoint inhibitors colitis (CIC) presents with watery or bloody diarrhea and, in the case of severe symptoms, requires ICIs discontinuation. The pathogenesis of CIC is multifactorial and still partially unknown: anti-tumor activity that collaterally effects the colonic tissue and the upregulation of specific systemic inflammatory pathways (i.e., CD8+ cytotoxic and CD4+ T lymphocytes) are mainly involved. Many questions remain regarding treatment timing and options, and biological treatment, especially with anti-TNF alpha, can be offered to these patients with the aim of rapidly resuming oncological therapies. CIC shares similar pathogenesis and aspects with inflammatory bowel disease (IBD) and the use of ICI in IBD patients is under evaluation. This review aims to summarize the pathogenetic mechanism underlying CIC and to discuss the current evidenced-based management options, including the role of biological therapy, emphasizing the relevant clinical impact on CIC and the need for prompt recognition and treatment.

Gastrointestinal treatment-related adverse events of combined immune checkpoint inhibitors: a meta-analysis

Introduction: Combined immune checkpoint inhibitors can cause gastrointestinal adverse events. Methods: We performed a meta-analysis of pooled colonic, hepatic and pancreatic treatment-related adverse events of combined ICI. Results: 53 trials reporting treatment-related adverse events in 6581 patients. All grade diarrhea was the most common adverse event seen in 25.4% patients, followed by all grade hepatitis in nearly 13% patients and pancreatitis in nearly 7.5% patients. Conclusion: Our study provides pooled data of treatment-related adverse events from different combination immune checkpoint inhibitors use in solid tumors and demonstrates a high incidence of all grades and ≥3 grade gastrointestinal adverse events. Further studies are required to characterize these adverse events and assess their overall impact on treatment course and outcomes.

Gut microbiome homeostasis and the future of probiotics in cancer immunotherapy

The gut microbiome has an impact on cancer immune surveillance and immunotherapy, with recent studies showing categorical differences between immunotherapy-sensitive and immunotherapy-resistant cancer patient cohorts. Although probiotics are traditionally being supplemented to promote treatments or sustain therapeutic benefits; the FDA has not approved any for use with immunotherapy. The first step in developing probiotics for immunotherapy is identifying helpful or harmful bacteria down to the strain level. The gut microbiome's heterogeneity before and during treatment is also being investigated to determine microbial strains that are important for immunotherapy. Moreover, Dietary fiber intake, prebiotic supplementation and fecal microbiota transplantation (FMT) were found to enhance intratumoral CD8+ T cell to T-reg ratio in the clinics. The possibility of probiotic immunotherapy as a "living adjuvant" to CAR treatment and checkpoint blockade resistance is actively being investigated.

Toward the next generation EGFR inhibitors: an overview of osimertinib resistance mediated by EGFR mutations in non-small cell lung cancer

Epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) is currently the standard first-line therapy for EGFR-mutated advanced non-small cell lung cancer (NSCLC). The life quality and survival of this subgroup of patients were constantly improving owing to the continuous iteration and optimization of EGFR-TKI. Osimertinib, an oral, third-generation, irreversible EGFR-TKI, was initially approved for the treatment of NSCLC patients carrying EGFR T790M mutations, and has currently become the dominant first-line targeted therapy for most EGFR mutant lung cancer. Unfortunately, resistance to osimertinib inevitably develops during the treatment and therefore limits its long-term effectiveness. For both fundamental and clinical researchers, it stands for a major challenge to reveal the mechanism, and a dire need to develop novel therapeutics to overcome the resistance. In this article, we focus on the acquired resistance to osimertinib caused by EGFR mutations which account for approximately 1/3 of all reported resistance mechanisms. We also review the proposed therapeutic strategies for each type of mutation conferring resistance to osimertinib and give an outlook to the development of the next generation EGFR inhibitors. Video Abstract.

Implication of the Gut Microbiome and Microbial-Derived Metabolites in Immune-Related Adverse Events: Emergence of Novel Biomarkers for Cancer Immunotherapy

Immune checkpoint inhibitors (ICIs) have changed how we think about tumor management. Combinations of anti-programmed death ligand-1 (PD-L1) immunotherapy have become the standard of care in many advanced-stage cancers, including as a first-line therapy. Aside from improved anti-tumor immunity, the mechanism of action of immune checkpoint inhibitors (ICIs) exposes a new toxicity profile known as immune-related adverse effects (irAEs). This novel toxicity can damage any organ, but the skin, digestive and endocrine systems are the most frequently afflicted. Most ICI-attributed toxicity symptoms are mild, but some are severe and necessitate multidisciplinary side effect management. Obtaining knowledge on the various forms of immune-related toxicities and swiftly changing treatment techniques to lower the probability of experiencing severe irAEs has become a priority in oncological care. In recent years, there has been a growing understanding of an intriguing link between the gut microbiome and ICI outcomes. Multiple studies have demonstrated a connection between microbial metagenomic and metatranscriptomic patterns and ICI efficacy in malignant melanoma, lung and colorectal cancer. The immunomodulatory effect of the gut microbiome can have a real effect on the biological background of irAEs as well. Furthermore, specific microbial signatures and metabolites might be associated with the onset and severity of toxicity symptoms. By identifying these biological factors, novel biomarkers can be used in clinical practice to predict and manage potential irAEs. This comprehensive review aims to summarize the clinical aspects and biological background of ICI-related irAEs and their potential association with the gut microbiome and metabolome. We aim to explore the current state of knowledge on the most important and reliable irAE-related biomarkers of microbial origin and discuss the intriguing connection between ICI efficacy and toxicity.

Blood cell counts can predict adverse events of immune checkpoint inhibitors: A systematic review and meta-analysis

Background

Cancer is concerning owing to its high mortality rate. Consequently, methods of prolonging the life of patients with cancer have become the primary focus of attention research. In recent years, immune checkpoint inhibitors (ICIs) have achieved good clinical efficacy as antitumor drugs; however, their severe adverse effects have made their use challenging. In order to clarify the predictors of adverse effects, scientists have conducted a series of studies. Blood counts can potentially monitor risk factors associated with the occurrence of immune-related adverse events (irAEs). Herein, a meta-analysis was performed to clarify further the guiding significance of blood counts in the clinical setting.

Methods

Studies that satisfied the inclusion criteria were obtained by searching the database. Included studies were those in which irAEs had been observed, and evidence of an association between blood counts and irAEs was reported. The included ones were evaluated for quality. In addition to sensitivity analysis and subgroup analysis, a meta-analysis was performed using the odds ratio (OR) and 95% confidence interval (CI) for each study.

Results

A total of 18 articles were included in our study. The analyses were performed separately according to different blood cell count indicators. The blood cell count metrics associated with irAEs were: absolute eosinophil count, neutrophil: lymphocyte ratio, and platelet: lymphocyte ratio.

Conclusion

Our review and meta-analysis of studies suggest that absolute eosinophil count, neutrophil: lymphocyte ratio, and platelet: lymphocyte ratio may serve as predictors of the emergence of irAEs. Given the small number of studies focusing on the relationship between patient blood cell counts and the risk of irAEs, future studies need to further explore the mechanisms of occurrence and potential associations.

Immune-Related Colitis Induced by Camrelizumab: A Case Report

In recent years, immunotherapy has become a major research focus in the field of cancer treatment. Because of its good efficacy and lasting immune response, immune checkpoint inhibitors have benefited the long-term survival of many types of cancer patients. However, overactivation of the immune system may attack normal organs and cause a series of immune related adverse reactions. Among them, due to the high incidence of immune-related colitis, it deserves special attention. Camrelizumab is a programmed cell death 1 (PD-1) inhibitor that was developed by Jiangsu Hengrui Medicine Company. We reported the clinical data of a case of hepatocellular carcinoma with immune-related colitis after treatment with camrelizumab. A 63-year-old man with hepatocellular carcinoma developed diarrhea and hematochezia after receiving 4 cycles of camrelizumab. Endoscopy showed multiple flake congestion and edema in the terminal ileum and total colon mucosa with bright red surface. Pathological evaluation showed chronic inflammation of colonic mucosa. After giving 0.25g bid of enteric-coated sulfasalazine tablets orally for 6 weeks, his colitis improved. Camrelizumab can induce immune-related colitis. Sulfasalazine could be used to reduce adverse reactions of glucocorticoids.

Check this out: treatment paradigms in immune-checkpoint inhibitor colitis

PURPOSE OF REVIEW

Immune checkpoint inhibitors (ICI) have become a pillar of cancer therapy for many people around the world. However, up to two-thirds of all patients undergoing ICI therapy will have immune-related adverse events (irAEs), including immune-checkpoint inhibitor colitis (ICIC). This review summarizes the most valuable and currently available information about the mechanism, diagnosis, and management of ICIC.

RECENT FINDINGS

Recent findings include several developments on the leading theories for the mechanisms of ICIC such as the role of the gut microbiome. New emerging therapy strategies include tocilizumab, ustekinumab, mycophenolate mofetil, and calcineurin inhibitors.

SUMMARY

The occurrence of irAEs remains a limiting factor for the use of immunotherapy in cancer treatment. Prompt diagnosis of ICIC with endoscopy and histologic confirmation can lead to early utilization of known effective treatments such as corticosteroids, infliximab, vedolizumab, and other emerging therapy strategies. We summarize the key points of this review article in our abstract video, Supplemental Digital Content 1, http://links.lww.com/COG/A44.

Refractory Checkpoint Inhibitor Colitis Responsive to Ustekinumab

Immune checkpoint inhibitors have transformed the treatment of cancer. Nonetheless, multiple immune-related adverse events have been reported, including checkpoint inhibitor colitis. Severe colitis can be complicated by ileus, megacolon, intestinal perforation, and death. Current appropriate treatment includes steroids, followed by antitumor necrosis factor biologic therapy, infliximab. Alternatively, vedolizumab and fecal microbiota transplantation have reported efficacy for refractory cases. In this study, we present the first case report of a patient with steroid-refractory checkpoint inhibitor-induced colitis due to pembrolizumab for Stage IV anaplastic thyroid carcinoma successfully treated with ustekinumab after failure of infliximab, vedolizumab, and fecal microbiota transplantation. This may lead to a better understanding of treatment options for refractory checkpoint inhibitor colitis.

Dietary Considerations for Inflammatory Bowel Disease Are Useful for Treatment of Checkpoint Inhibitor-Induced Colitis

Checkpoint molecules are cell surface receptors on immune cells that mitigate excessive immune responses, but they have increased expression levels in cancer to facilitate immune escape. Checkpoint blockade therapies (e.g., anti-PD-1, anti-CTLA-4, and anti-LAG-3 therapy, among others) have been developed for multiple cancers. Colitis associated with checkpoint blockade therapy has pathophysiological similarities to inflammatory bowel disease (IBD), such as Crohn's disease and ulcerative colitis. Current therapeutic guidelines for checkpoint blockade-induced colitis include corticosteroids and, if the patient is refractory to steroids, immunomodulating antibodies, such as anti-TNF and anti-integrin agents. Interestingly, immunomodulatory molecules, such as TNFα, are upregulated in both IBD and checkpoint-mediated colitis. The inflammatory colitis toxicity symptoms from checkpoint blockade are similar to clinical symptoms experienced by patients with IBD. The pathophysiologic, dietary, and genetic factors associated with IBD will be reviewed. We will then explain how the principles developed for the treatment of IBD can be applied to patients experiencing inflammatory bowel toxicity secondary to checkpoint blockade.

A case of perforated immune-related colitis complicated by cytomegalovirus infection during treatment of immune-related adverse effect in lung cancer immunotherapy

Although immune checkpoint inhibitors (ICIs) can be used for lung cancer treatment, the activated immune response may cause immune-related adverse effects (irAEs). We present here a case of cytomegalovirus (CMV) enterocolitis during steroid therapy for an irAE. A 70-year-old man diagnosed with small-cell lung carcinoma (limited disease) received radiotherapy plus two chemotherapy cycles of cisplatin and etoposide. The tumor exhibited complete response but recurred after 3 years. After treatment with two cycles of carboplatin, etoposide, and atezolizumab, an inhibitors of programmed cell death receptor-1, he was switched to atezolizumab every 3 weeks for maintenance therapy. Diarrhea occurred after nine atezolizumab doses. With a strong suspicion of ICI-induced colitis, we administered methylprednisolone 500 mg for 3 days, followed by oral prednisolone 40 mg/day. Total colonoscopy during the treatment revealed mucosal inflammation of the total colon, suggesting immune-related colitis. Biopsies from the ulceration revealed crypt abscess with highly infiltrative plasma cells and lymphocytes. Furthermore, immunohistochemical staining showed positivity for CMV. With no improvement in watery diarrhea, the prednisolone dose was increased to 80 mg/day on the 11th day, and ganciclovir was additionally administered twice daily on the 26th day. On the 28th day, the patient had abdominal pain, and abdominal computed tomography revealed free air, resulting in the diagnosis of colon perforation. He underwent subtotal colectomy followed by ileostomy as emergency surgery. A colon specimen revealed colitis with CMV infection. We describe colon perforation in a patient with CMV enterocolitis complicated by refractory immune-related colitis.

Multiple White Plaques in the Esophagus: A Possible Case of Esophageal Mucosal Alteration Associated With Immune-Related Adverse Events of Immune Checkpoint Inhibitors

We report two cases of multiple white plaques in the esophagus that emerged after the administration of immune checkpoint inhibitors. Both patients developed enterocolitis as immune-related adverse events associated with immune checkpoint inhibitors. Esophagogastroduodenoscopy revealed duodenal involvement and multiple white plaques in the esophagus. A biopsy of the esophagus showed predominant CD3⁺ lymphocyte infiltration, suggesting that esophageal mucosal alterations were associated with immune-related adverse events. In addition, histopathology showed keratinized stratified squamous epithelium in the first case while increased inflammatory cell infiltration in the intraepithelial and subepithelial layers was observed in the second case. These data suggest a different pathogenesis of the multiple esophageal white plaques between the two cases. Although further investigation is needed to elucidate the significance of these observations, recognition of the esophageal plaques may be important for prompt diagnosis of immune-related adverse events when associated with immune checkpoint inhibitors.

Identification of potential immunomodulators from Pulsatilla decoction that act on therapeutic targets for ulcerative colitis based on pharmacological activity, absorbed ingredients, and in-silico molecular docking

BACKGROUND

Pulsatilla decoction (Bai-Tou-Weng-Tang, BTWT) is a classic formula prescription of a traditional Chinese medicine that is used to treat ulcerative colitis (UC). However, its active components and underlying mechanism of action remain unclear. In the present study, we aimed to identify potential immunomodulators from BTWT that act at therapeutic targets for UC.

METHODS

The protective effects of BTWT granules were examined in mice with colitis induced by dextran sulfate sodium. The absorbed components of BTWT were identified using LC-MS, and selected protein targets of these components in UC were investigated using molecular docking.

RESULTS

Oral administration of BTWT granules significantly alleviated disease severity and colon shortening, and inhibited the inflammatory response in mice with chronic colitis. In these mice, 11 compounds from the BTWT granules were detected in the serum and/or colon. The molecular docking study demonstrated that compounds from Radix pulsatillae, such as anemoside A3, interacted with STAT3 and S1PR1; compounds from Rhizoma coptidis and/or Cortex phellodendri, such as palmatine, interacted with JAK3, PD-1, and PD-L1; and components of Cortex fraxini such as aesculin interacted with S1PR1, JAK3, STAT3 and PD-L1. Further in-vitro experiments showing that the compounds inhibited TNF-α and IL-6 production and STAT3 activation in RAW 264.7 cells suggested that these compounds have immunomodulatory activities.

CONCLUSION

We revealed for the first time that 11 absorbed ingredients from BTWT were immunomodulators against therapeutic targets for UC. These findings suggest that the identified compounds are the active components of BTWT, and the identified protein targets underlie the mechanism of action of BTWT against UC.

Interaction between gut microbiota and immune checkpoint inhibitor-related colitis

Immune checkpoint inhibitors (ICIs) have become a promising therapeutic strategy for malignant tumors, improving patient prognosis, along with a spectrum of immune-related adverse events (irAEs), including gastrointestinal toxicity, ICI-related colitis (IRC), and diarrhea. The gut microbiota has been suggested as an important regulator in the pathogenesis of IRC, and microbiota modulations like probiotics and fecal microbiota transplantation have been explored to treat the disease. This review discusses the interaction between the gut microbiota and IRC, focusing on the potential pathogenic mechanisms and promising interventions.

Case Report: Treatment for steroid-refractory immune-related myocarditis with tofacitinib

Introduction

Immune therapy has ushered in a new era of tumor treatment, at the expense of immune-related adverse events, including rare but fatal adverse cardiovascular events, such as myocarditis. Steroids remain the cornerstone of therapy for immune-related myocarditis, with no clear consensus on additional immunosuppressive treatment for steroid-refractory cases yet.

Case report

Here, we report a patient with stage IV nasopharyngeal carcinoma who developed immune-related myocarditis in the fourth course of therapy with immune checkpoint inhibitors. The patient presented with precordial discomfort with elevation of cardiac enzymes and interleukin-6, atypical electrocardiographic abnormalities, and reduced left ventricular ejection fraction. Coronary computed tomography angiography excluded the possibility of acute coronary syndrome. The therapy with tofacitinib targeting the Janus kinase-signal transducer and activator of transcription signal pathway was successfully conducted, since there was no significant improvement in troponin under high-dose steroid and intravenous immunoglobulin treatment. The patient recovered without major adverse cardiac events during hospitalization.

Discussion

The safety and efficacy of tofacitinib in a patient with steroid-refractory immune-related myocarditis were investigated, hoping to provide a basis for prospective therapeutic strategies. Tofacitinib led to remarkable remissions in primary autoimmune disease by blocking the inflammatory cascade, indicating its potential therapeutic use in immune-related adverse events.

The multifaceted roles of common gut microbiota in immune checkpoint inhibitor-mediated colitis: From mechanism to clinical application

With the arrival of the era of tumor immunotherapy, Immune Checkpoint Inhibitors have benefited countless tumor patients. However, the emergence of Immune-Related Adverse Events, especially Immune Checkpoint Inhibitor-Mediated Colitis (IMC), has become an important obstacle to immunotherapy. Therefore, it is very important to clarify the mechanism and influencing factors of IMC. The effect of gut microbiota on IMC is gradually becoming a research hotspot. Gut microbiota from different phyla can affect IMC by regulating innate and acquired immunity of tumor patients in various ways. In this review, we make a systematic and comprehensive introduction of the effect of gut microbiota on IMC. Through understanding the specific effects of gut microbiota on IMC, and then exploring the possibility of reducing IMC by regulating gut microbiota.