Immune checkpoint Inhibitor–Induced diarrhea and Colitis: Incidence and Management. A systematic review and Meta-analysis

Engineering Escherichia coli Nissle 1917 Carrying PD1 Agonists Resolves Intestinal Inflammation via Local Immune Modulation

Immunological imbalance is a key factor in the progression of intestinal inflammation, yet effective treatments remain elusive. Using a radiation-induced intestinal injury model, we investigated the causes of inflammation at the single-cell level and identified abnormal T-cell activation as a major contributor. To address this, we targeted the PD1 signaling pathway to suppress T-cell activation and evaluated the anti-inflammatory and intestinal repair effects of the PD1 agonist displaying probiotic Escherichia coli Nissle 1917 (EcNMP1-M) in two mouse models. Encapsulated in Eudragit L100-55 for pH-dependent release, EcNMP1-M and its bacterial outer membrane vesicles (OMVs) expressed PD1 agonists, which inhibited excessive immune activation and reduced inflammatory cytokines. EcNMP1-M promoted the expression of proteins that maintain intestinal epithelial barrier integrity, improving gut function and immune responses in colitis mice. Furthermore, 16S rDNA microbiome sequencing revealed that EcNMP1-M enhanced intestinal microbiota diversity, increased beneficial bacteria, and reduced harmful bacteria. This study proposes a localized EcN-based immunosuppressive therapy for radiation-induced enteritis and inflammatory bowel disease with promising potential for clinical applications.

Management of refractory checkpoint inhibitor-induced colitis

INTRODUCTION

This review discusses the epidemiology, pathophysiology, and factors associated with refractory immune-mediated diarrhea and colitis (r-IMDC), emphasizing tailored treatment strategies.

AREAS COVERED

The current literature on r-IMDC was reviewed using PubMed (2015-2025), focusing on clinical trials, meta-analyses, and case reports relevant to its management.

EXPERT OPINION

Effectively managing r-IMDC is crucial for balancing toxicities and antitumor response. Available second and third-line management options for r-IMDC cases must be carefully evaluated. Future perspectives include development of standardized protocols beyond second-line therapies and predictive biomarkers to enable personalized treatment.

Preclinical insights into the potential of itaconate and its derivatives for liver disease therapy

Annually, approximately 3.5 % of the world's population dies of cirrhosis or liver cancer, and the burden of liver disease is steadily expanding owing to multiple factors such as alcohol consumption, irrational diets, viral transmission, and exposure to drugs and toxins. However, the lack of effective therapies and the adverse effects of some medications remain a threat to the management of liver disease. Recently, immunometabolism, as an emerging discipline, appears to be the focus of unprecedented research. As a natural metabolite that regulates cellular functions, itaconate is a crucial bridge connecting metabolism and immune response. Remodeling immune function through metabolic modulation may be a promising alternative for disease intervention strategies. In this review, we first briefly describe the historical origin of itaconate and the development of its derivatives. This was followed by a review of the molecular mechanisms by which itaconate regulated immune-metabolic responses. Furthermore, we analyzed the effects of itaconate regulation on immune cells of the hepatic system. Finally, we summarized the experimental evidence for itaconate and its derivatives in the therapeutic application of liver diseases. Itaconate is potentially an invaluable component of emerging therapeutic strategies for liver disease.

An updated review on immune checkpoint inhibitor-induced colitis: epidemiology, pathogenesis, treatment strategies, and the role of traditional Chinese medicine

Immune checkpoint inhibitor-induced colitis (irColitis) is a common and severe adverse reaction to immune checkpoint inhibitors (ICIs), significantly impacting the treatment outcomes and quality of life of cancer patients. Epidemiological studies indicate that the incidence of irColitis is associated with factors such as the type of ICIs, the patient's gender, age, and medical history. Although the exact pathophysiology remains unclear, irColitis is thought to be related to immune system activation and dysregulation, gut microbiota imbalance, and impaired epithelial barrier function. This review summarized the epidemiology, clinical presentation, diagnostic criteria, and pathogenesis of irColitis. Additionally, the standard and novel therapeutic strategies of irColitis, including corticosteroids, biologics, and gut microbiota interventions, more importantly the potential and application of Traditional Chinese Medicine (TCM). Future researches call for deeper mechanistic investigations, the development of biomarkers, and reveal the integration of TCM therapies within individual immunotherapy frameworks.

Gastrointestinal toxicities associated with immune checkpoint inhibitors therapy: risks and management

Immune checkpoint inhibitors (ICIs) have greatly improved cancer treatment by boosting the immune system's ability to target tumors. However, they can also cause serious side effects, particularly in the digestive system. These include immune-related diarrhea, inflammation of the intestines and, less commonly, inflammation of the stomach or esophagus. This review underscores the importance of early detection, accurate diagnosis, and timely treatment to improve patient outcomes. It also highlights the need for further research to develop strategies to reduce gastrointestinal toxicities and enhance the overall effectiveness of ICIs in cancer therapy.

Incidence of and Risk Factors for Anti-PD-1/PD-L1- Associated Diarrhea and Colitis: A Retrospective Cohort Study of the Chinese Population

Background and Objectives: The prevalence of and risk factors for immune checkpoint inhibitor-associated diarrhea and colitis (IMDC) in the Chinese population are unclear. This study aimed to estimate IMDC incidence and identify potential risk factors. Materials and Methods: We reviewed the electronic medical records from Beijing Friendship Hospital (2015-2022) to identify the patients treated with immune checkpoint inhibitors. The primary outcome was IMDC occurrence. The demographics, cancer type, baseline labs, and concurrent medications were analyzed. The univariable and multivariable analyses validated the associated factors. Results: Among 1186 patients (median follow-up: 217 days), the IMDC incidence was 4.6%, with colitis at 0.67%. Digestive system tumors increased the IMDC risk (OR 2.79, 95% CI 1.42-5.75, p = 0.004), while platinum agents decreased it (OR 0.41, 95% CI 0.21-0.78, p = 0.008). PPIs, antibiotics, NSAIDs, and glucocorticoids showed no significant association. Colitis was the third most common irAE, leading to ICI discontinuation (15.6%). Conclusions: IMDC prevalence is 4.6% in the Chinese population, the third most frequent irAE causing ICI discontinuation. Digestive tumors and platinum agents are risk and protective factors, respectively, while other medications show no significant impact.

Comparisons of adverse events associated with immune checkpoint inhibitors in the treatment of non-small cell lung cancer: a real-world disproportionality analysis based on the FDA adverse event reporting system

BACKGROUND

Immune checkpoint inhibitor (ICI) therapy is increasingly used to treat non-small cell lung cancer (NSCLC). However, little attention has been given to the comparative analysis of adverse events (AEs) associated with different ICIs.

METHODS

Disproportionality analysis and Bayesian confidence propagation neural network (BCPNN) were utilized to identify pharmacovigilance signals from the FDA Adverse Event Reporting System (FAERS). We compared the sex distribution of patients, risk of suffering more severe adverse reactions, and risk of hospitalization associated with different ICIs, using pairwise matrices that displayed odds ratio (OR) and their 95% confidence interval (CI). And we also compared the outcomes of reactions by using ordinal logistic regression.

RESULTS

We analyzed 13,580 reports of AEs associated with five ICIs, namely, durvalumab, pembrolizumab, ipilimumab, atezolizumab, and nivolumab from January 2013 to October 2022. Significant differences were observed in sex distribution of patients, risk of suffering more severe adverse reactions, risk of hospitalization, and the outcomes of reactions. In terms of respiratory AEs, pembrolizumab exhibited a higher risk compared to durvalumab (OR = 2.48, 95% CI: 1.72-3.59), atezolizumab (OR = 1.84, 95% CI: 1.07-3.16), and nivolumab (OR = 4.21, 95% CI: 1.72-10.28), while ipilimumab exhibited a higher risk compared to durvalumab (OR = 2.76, 95% CI: 1.14-6.65) and nivolumab (OR = 4.67, 95% CI: 1.14-15.51). In terms of endocrine and metabolic AEs, durvalumab (OR = 7.80, 95% CI: 1.33-45.90) and nivolumab (OR = 5.20, 95% CI: 1.17-23.03) exhibited a higher risk compared to ipilimumab.

CONCLUSION

Each ICI has distinctive features of pharmacovigilance signals. It is essential to acknowledge the AEs associated with the relevant system when clinicians administer ICIs.

Update on the Epidemiology and Management of Microscopic Colitis

Microscopic colitis is an inflammatory bowel disease that commonly presents with debilitating chronic watery diarrhea. Recent epidemiologic studies and randomized trials of therapeutics have improved the understanding of the disease. Medications, such as nonsteroidal anti-inflammatories, proton pump inhibitors, and antidepressants, have traditionally been considered as the main risk factors for microscopic colitis. However, recent studies have challenged this observation. Additionally, several epidemiologic studies have identified other risk factors for the disease including older age, female sex, smoking, alcohol use, immune-mediated diseases, and select gastrointestinal infections. The diagnosis of microscopic colitis requires histologic assessment of colon biopsies with findings including increased in intraepithelial lymphocytes with or without expansion of the subepithelial collagen band. The pathophysiology is poorly understood but is thought to be related to an aberrant immune response to the luminal microenvironment in genetically susceptible individuals. Antidiarrheal medications, such as loperamide or bismuth subsalicylate, may be sufficient in patients with mild symptoms. In patients with more severe symptoms, treatment with budesonide is recommended. Maintenance therapy is often necessary and several potential treatment strategies are available. Biologic and small molecule treatments seem to be effective in patients who have failed budesonide. There is an unmet need to further define the pathophysiology of microscopic colitis. Additionally, trials with novel therapies, particularly in patients with budesonide-refractory disease, are needed.

Development and validation of a nomogram for predicting immune-mediated colitis in lung cancer patients treated with immune checkpoint inhibitors: a retrospective cohort study in China

Background

The increasing utilization of immune checkpoint inhibitors (ICIs) has led to a concomitant rise in the incidence of immune-related adverse events (irAEs), notably immune-mediated colitis (IMC). This study aimed to identify the clinical risk factors associated with IMC development in patients with lung cancer and to develop a risk prediction model to facilitate personalized treatment and care strategies.

Methods

The data collected included 21 variables, including sociodemographic characteristics, cancer-related factors, and routine blood markers. The dataset was randomly partitioned into a training set (70%) and a validation set (30%). Univariate and multivariate logistic regression analyses were conducted to identify independent predictors of IMC development. On the basis of the results of the multivariate analysis, a nomogram prediction model was developed. Model performance was assessed via the area under the receiver operating characteristic curve (AUC), calibration curve analysis, decision curve analysis (DCA), and clinical impact curve (CIC).

Results

Among the 2103 patients, 66 (3.14%) developed IMCs. Multivariate logistic regression analysis revealed female sex, small cell lung cancer (SCLC), elevated β2 microglobulin (β2-MG) and globulin (GLB) levels, and an increased neutrophil-lymphocyte ratio (NLR) as independent predictors of IMC development (all P < 0.05). Conversely, a higher white blood cell (WBC) count, CD4/CD8 ratio, and platelet-lymphocyte ratio (PLR) were identified as factors associated with a reduced risk of IMC development (all P < 0.05). The nomogram prediction model demonstrated good discrimination, achieving an AUC of 0.830 (95% CI: 0.774-0.887) in the training set and 0.827 (95% CI: 0.709-0.944) in the validation set. Analysis of the calibration curve, DCA, and CIC indicated good predictive accuracy and clinical utility of the developed model.

Conclusion

This study identified eight independent predictors of IMC development in patients with lung cancer and subsequently developed a nomogram-based prediction model to assess IMC risk. Utilization of this model has the potential to assist clinicians in implementing appropriate preventive and therapeutic strategies, ultimately contributing to a reduction in the incidence of IMC among this patient population.

Potential drugs for reducing the occurrence of immune checkpoint inhibitor-induced interstitial lung disease: an exploratory study using the JADER and FAERS databases

BACKGROUND

Immune checkpoint inhibitors (ICIs) play a central role in cancer immunotherapy. However, the occurrence of immune-related adverse events, especially ICI-induced interstitial lung disease (ICI-ILD), is life-threatening and affects the effectiveness of ICI treatment. This study aimed to explore potential drugs to mitigate ICI-ILD occurrence using data from the Japanese Adverse Drug Event Report (JADER) and the US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS [JAPIC AERS]).

RESEARCH DESIGN AND METHODS

We investigated concomitant drugs that reduce ILD associated with four ICIs - nivolumab, pembrolizumab, atezolizumab, and durvalumab - across the JADER and FAERS databases. Subsequently, the identified common concomitant drugs that reduce the occurrence of ICI-ILD were detected and analyzed.

RESULTS

We found omega-3 fatty acids, loperamide, and amlodipine as common concomitant drugs that reduced ICI-ILD occurrence in both the JADER and FAERS databases. Omega-3 fatty acids reportedly have many effects in animal models of drug-induced ILD, including their association with ILD in humans and anti-inflammatory effects against ICI-ILD. However, loperamide and amlodipine reportedly have minimal effects against ILD, thereby necessitating further evaluation.

CONCLUSION

Omega-3 fatty acids have emerged as potential agents for reducing ICI-ILD occurrence, as evidenced by findings from two different pharmacovigilance databases.

Systematic review of immune checkpoint inhibitor-related gastrointestinal, hepatobiliary, and pancreatic adverse events

Gastrointestinal immune-related adverse events (GI irAEs) are common manifestations of immune checkpoint inhibitor (ICI) toxicity. We present a comprehensive systematic review of the incidence, management, and clinical course of irAEs across the entire GI system, including the luminal GI tract, liver, and pancreas. MEDLINE, Embase, Web of Science Core Collection, and Cochrane Library were used to conduct this review. All studies pertaining to GI irAEs were included. Both abstracts and full manuscripts were eligible if they included human subjects and were written in the English language. Articles not available in English, animal studies, or research not specific to GI toxicity of immunotherapy were excluded. We excluded certain article types depending on whether stronger evidence was available in the literature for a specific toxicity, for example, if prospective studies were available on a topic, retrospective studies and case reports were excluded. We extracted a final 166 articles for our review and followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for data reporting. Risk of bias tools were not used to evaluate the extracted studies given the narrative nature of this manuscript, but each study was critically appraised by the manuscript writer. We detail the incidence, presentation, evaluation, management, and outcomes of the various GI toxicities that may arise with ICI therapy. Specifically, we discuss the characteristics of upper GI toxicity (esophagitis and gastroenteritis), lower GI toxicity (colitis), hepatobiliary inflammation, pancreatitis, and rarer forms of GI toxicity. We hope this review serves as a useful and accessible clinical tool that helps physicians familiarize themselves with the nuances of gastrointestinal/hepatic/pancreatic ICI toxicity diagnosis and management.

Gastrointestinal adverse events associated with immune checkpoint inhibitors: a pharmacovigilance analysis of the EudraVigilance and VigiAccess databases

BACKGROUND

This study aimed to provide an overview of gastrointestinal (GI) adverse events associated with immune checkpoint inhibitors (ICIs) using two pharmacovigilance databases, EudraVigilance and VigiAccess.

RESEARCH DESIGN AND METHODS

Data was collected from the date of ICI's marketing authorization until 30 November 2023. Reporting odds ratio (ROR) was used as a measure of ADR reporting disproportionality for signal detection.

RESULTS

Overall, across both databases, EudraVigilance and VigiAccess, a total of 76,606 ADR reports were analyzed. In EudraVigilance, colitis (12,581) and diarrhea (12,108) were the most reported GI adverse events, with similar findings in VigiAccess. Furthermore, in both databases, the most ADR reports were associated with nivolumab and pembrolizumab. Durvalumab (ROR:3.96,95%CI:3.65-4.28), ipilimumab (ROR:1.95,95%CI:1.89-2.01), nivolumab (ROR:1.05,95%CI:1.02-1.07), and atezolizumab (ROR:1.04,95%CI:1.01-1.07) demonstrated higher risks of GI events compared to other ICIs. EudraVigilance analysis identified dysphagia, ascites, hematochezia, and gastroesophageal reflux disease as potential signals associated with ICI therapy. Majority of ADR reports (87.2%) comprised serious GI adverse events, a portion of which was associated with fatal outcomes (14.5%). Atezolizumab (14.9%) and pembrolizumab (11.9%) were linked to a higher incidence of fatal outcomes compared to other ICIs.

CONCLUSION

The differential risk profiles of ICIs-associated-GI adverse events underscore the importance of personalized therapy in oncology.

Immune Checkpoint Inhibitor-Induced Cardiotoxicity: A Systematic Review and Meta-Analysis

Importance

Immune checkpoint inhibitors (ICIs) improve outcomes in a wide range of cancers; however, serious adverse effects, including cardiovascular adverse effects (CVAEs), can occur.

Objective

To determine the incidence of CVAEs and analyze data on the management of myocarditis in patients exposed to ICIs.

Data Sources

PubMed, Embase, and Cochrane Central Register of Controlled Trials from inception were searched on April 4, 2023.

Study Selection

Two separate studies were performed. Key inclusion criteria for study 1 were phases 1 to 4 trials involving adults with malignant neoplasms treated with an ICI and toxicity data; for study 2, publications (case reports and retrospective analyses) on clinical manifestations and treatment of patients with ICI-induced CVAEs. Studies with dose escalation or fewer than 11 patients in each group and all case reports, retrospective analyses, letters, reviews, and editorials were excluded from study 1. Studies not published in English were excluded from study 2.

Data Extraction and Synthesis

The PRISMA guidelines and Cochrane Handbook for Systematic Reviews were followed. Data were extracted independently by 2 researchers. A meta-analysis of the incidence of CVAEs in clinical trials and a systematic review of the evidence for the management of myocarditis were performed. Data were pooled using a random-effects model.

Main Outcomes and Measures

In study 1, the primary outcome was incidence CVAEs in clinical trials with ICIs and ICI combination therapies. Study 2 examined evidence supporting specific management strategies that may decrease the mortality rate of myocarditis. The primary outcomes were planned before data collection began.

Results

In study 1, a total of 83 315 unique participants in 589 unique trials were included in the meta-analysis. Incidence of CVAEs induced by anti-programmed cell death 1 and/or programmed cell death ligand 1 was 0.80% (95% CI, 0%-1.66%) in clinical trials, with no differences between the compounds, except for cemiplimab, which was associated with a higher risk of CVAEs. Incidence of CVAEs following ipilimumab treatment was 1.07% (95% CI, 0%-2.58%). The incidence of myocarditis was significantly higher following treatment with dual ICIs. However, CVAE incidence was not higher with dual ICIs, ICI combination with chemotherapy, or tyrosine kinase inhibitors. Evidence from randomized clinical trials on recommended monitoring and treatment strategies for ICI-induced myocarditis was lacking. Study 2 showed that myocarditis-associated mortality occurred in 83 of 220 patients (37.7%). Prospective data from 40 patients with myocarditis indicated that systematic screening for respiratory muscle involvement, coupled with active ventilation, prompt use of abatacept, and the addition of ruxolitinib, may decrease the mortality rate.

Conclusions and Relevance

Immune checkpoint inhibitor-induced CVAEs and/or myocarditis were recorded in 1.07% of patients in clinical trials. The CVAE mortality risk remains high, justifying the need for monitoring and management strategies for which evidence from randomized clinical trials is absent. Early recognition, ICI therapy cessation, prompt initiation of corticosteroid therapy, and escalation of therapy are all crucial elements for achieving optimal outcomes. Prospective clinical trials or at least prospective registration of treatments and outcomes are highly warranted.

Bidirectional two-sample Mendelian randomization analysis investigates causal associations between cathepsins and inflammatory bowel disease

Background

Cathepsins, key regulators of the pathology of gastrointestinal disorders such as inflammatory bowel disease (IBD), are a target protease that has attracted much attention in recent years. IBD is a chronic and relapsing inflammatory disorder of the gut. Traditional studies have shown a correlation between cathepsin and the risk of IBD, while the causal relationship remains unclear.

Methods

This study utilized Mendelian randomization techniques to evaluate the causal relationships between eleven cathepsins and the subtypes of IBD, such as ulcerative colitis (UC) and Crohn's disease (CD). We also performed a series of sensitivity analyses to validate the primary Mendelian randomization (MR) results, including Cochran's Q test, the MR-PRESSO global test, and the MR pleiotropy test.

Results

The forward MR analyses showed no significant association between cathepsins and IBD. Reverse Mendelian randomization analyses suggested that UC might lead to elevated cathepsin G levels [inverse-variance weighted (IVW): p = 0.038, b = 9.966], and CD might cause a decrease in cathepsin B levels [IVW: p = 0.002, b = -10.525] and cathepsin L1 levels [IVW: p = 0.045, b = -4.742].

Conclusions

Our findings offer novel and comprehensive evidence on the impact of UC or CD on cathepsins, potentially providing valuable insights into the treatment and prognosis of IBD.

The correlation between immune-related adverse events and efficacy of immune checkpoint inhibitors

Immune checkpoint inhibitors have revolutionized cancer treatment by targeting the cytotoxic T lymphocyte antigen-4 and programmed death-1/ligand-1. Although immune checkpoint inhibitors show promising therapeutic efficacy, they often cause immune-related adverse events. Immune-related adverse events differ from the side effects of conventional chemotherapy and require vigilant monitoring. These events predominantly affect organs, such as the colon, liver, lungs, pituitary gland, thyroid and skin, with rare cases affecting the heart, nervous system and other tissues. As immune-related adverse events result from immune activation, indicating the reinvigoration of exhausted immune cells that attack both tumors and normal tissues, it is theoretically possible that immune-related adverse events may signal a better response to immune checkpoint inhibitor therapy. Recent retrospective studies have explored the link between immune-related adverse event development and clinical efficacy; however, the predictive value of immune-related adverse events in the immune checkpoint inhibitor response remains unclear. Additionally, studies have focused on immune-related adverse events, timing of onset and immunosuppressive treatments. This review focuses on pivotal studies of the association between immune-related adverse events and outcomes in patients treated with immune checkpoint inhibitors.

Atezolizumab-Induced Ulcerative Colitis in Patient with Hepatocellular Carcinoma: Case Report and Literature Review

Background and Objectives: Immune check inhibitor (ICI) colitis is one of most common and adverse side effects of ICI. However, there was no case report of ulcerative colitis (UC)-mimicking colitis after atezolizumab use in hepatocellular carcinoma (HCC) to our knowledge. Materials and Methods: We would like to introduce the case of a patient with Stage IV HCC who complained of abdominal pain, diarrhea and rectal bleeding after two cycles of atezolizumab/bevacizumab chemotherapy and was then diagnosed with UC-mimicking colitis. Results: Endoscopy revealed typical findings of UC, suggesting diagnosis of UC-mimicking colitis. The patient was treated with systemic steroids and oral mesalamine, which significantly improved his symptoms, which were also supported by endoscopic findings. The patient resumed chemotherapy with atezolizumab and bevacizumab without any interruption to the chemotherapy schedule. Conclusions: Early endoscopic evaluation is pivotal to diagnosing UC-mimicking colitis. If diagnosed, UC-based treatments such as steroids and mesalamine should be strongly considered. Given previous reports of inflammatory bowel disease (IBD) flare-ups after immunotherapy, routine lower endoscopy, performed together with upper endoscopy before atezolizumab/bevacizumab therapy, is promising to patients.

Immune-related adverse event-associated sclerosing cholangitis due to immune checkpoint inhibitors: imaging findings and treatments

OBJECTIVES

Immune-related adverse event-sclerosing cholangitis caused by treatment with immune checkpoint inhibitors is rare, and the diagnostic criteria and treatment strategy remain unclear. In this study, we confirmed the clinicopathological features of immune-related adverse event-sclerosing cholangitis and clarified its diagnosis and appropriate management.

METHODS

We retrospectively evaluated 10 patients diagnosed with immune-related adverse event-sclerosing cholangitis and identified by electronic database searches.

RESULTS

Blood tests revealed liver dysfunction with a predominance of biliary tract enzymes in all patients; however, jaundice was present in only one patient. Contrast-enhanced computed tomography revealed diffuse hypertrophy of the extrahepatic bile duct wall as the most frequent finding; however, endoscopic retrograde cholangiopancreatography showed various imaging features, such as the pruned-tree appearance of intrahepatic bile ducts, in all patients. Transpapillary bile duct biopsy showed inflammatory cell infiltration using immunostaining, with a predominance of cluster of differentiation 8-positive T cells in 63% of the cases. Initial steroid therapy was effective in two cases. Mycophenolate mofetil and tacrolimus were used in steroid-refractory cases. Although six patients showed improvements, all of the remaining patients died owing to immune-related adverse event-sclerosing cholangitis.

CONCLUSIONS

Various bile duct imaging findings of immune-related adverse event-sclerosing cholangitis were revealed; transpapillary bile duct biopsy may be useful in the diagnosis of immune-related adverse event-sclerosing cholangitis. Despite the combination of multiple immunosuppressive agents, prognosis of immune-related adverse event-sclerosing cholangitis remains poor. Longer follow-up and larger clinical studies are necessary to establish its treatment strategy.

Oral administration of CXCL12-expressing Limosilactobacillus reuteri improves colitis by local immunomodulatory actions in preclinical models

Treatments of colitis, inflammation of the intestine, rely on induction of immune suppression associated with systemic adverse events, including recurrent infections. This treatment strategy is specifically problematic in the increasing population of patients with cancer with immune checkpoint inhibitor (ICI)-induced colitis, as immune suppression also interferes with the ICI-treatment response. Thus, there is a need for local-acting treatments that reduce inflammation and enhance intestinal healing. Here, we investigated the effect and safety of bacterial delivery of short-lived immunomodulating chemokines to the inflamed intestine in mice with colitis. Colitis was induced by dextran sulfate sodium (DSS) alone or in combination with ICI (anti-PD1 and anti-CTLA-4), and Limosilactobacillus reuteri R2LC (L. reuteri R2LC) genetically modified to express the chemokine CXCL12-1α (R2LC_CXCL12, emilimogene sigulactibac) was given perorally. In addition, the pharmacology and safety of the formulated drug candidate, ILP100-Oral, were evaluated in rabbits. Peroral CXCL12-producing L. reuteri R2LC significantly improved colitis symptoms already after 2 days in mice with overt DSS and ICI-induced colitis, which in benchmarking experiments was demonstrated to be superior to treatments with anti-TNF-α, anti-α4β7, and corticosteroids. The mechanism of action involved chemokine delivery to Peyer's patches (PPs), confirmed by local CXCR4 signaling, and increased numbers of colonic, regulatory immune cells expressing IL-10 and TGF-β1. No systemic exposure or engraftment could be detected in mice, and product feasibility, pharmacology, and safety were confirmed in rabbits. In conclusion, peroral CXCL12-producing L. reuteri R2LC efficiently ameliorates colitis, enhances mucosal healing, and has a favorable safety profile.NEW & NOTEWORTHY Colitis symptoms are efficiently reduced by peroral administration of probiotic bacteria genetically modified to deliver CXCL12 locally to the inflamed intestine in several mouse models.

Novel endoscopic scoring system for immune mediated colitis: a multicenter retrospective study of 674 patients

BACKGROUND AND AIMS

No endoscopic scoring system has been established for immune-mediated colitis (IMC). This study aimed to establish such a system for IMC and explore its utility in guiding future selective immunosuppressive therapy (SIT) use compared to clinical symptoms.

METHODS

This retrospective, international, 14-center study included 674 patients who developed IMC after immunotherapy and underwent endoscopic evaluation. Ten endoscopic features were selected by group consensus and assigned 1 point each to calculate an IMC endoscopic score (IMCES). IMCES cutoffs were chosen to maximize specificity for SIT use. This specificity was compared between IMCESs, and clinical symptoms were graded according to a standardized instrument.

RESULTS

A total of 309 (45.8%) patients received SIT. IMCES specificity for SIT use was 82.8% with a cutoff of 4. The inclusion of ulceration as a mandatory criterion resulted in higher specificity (85.0% for a cutoff of 4). In comparison, the specificity of a Mayo endoscopic subscore of 3 was 74.6%, and the specificity of clinical symptom grading was much lower at 27.4% and 12.3%, respectively. Early endoscopy was associated with timely SIT use (P < .001; r = 0.4084).

CONCLUSIONS

This is the largest multicenter study to devise an endoscopic scoring system to guide IMC management. An IMCES cutoff of 4 has a higher specificity for SIT use than clinical symptoms, supporting early endoscopic evaluation for IMC.

Sequential severe immune-related adverse events induced by PD-1 inhibitor: a case report and literature review

In a variety of cancers, immune checkpoint inhibitors (ICIs) have demonstrated substantial survival advantages. Nevertheless, the widespread use of ICIs in the clinic has resulted in a growing interest in immune-related adverse events (irAEs) and their treatment methods. This paper reports a case in which a patient with three sequential severe irAEs was successfully treated. After undergoing two regimens of sintilimab in conjunction with chemotherapy for advanced lung cancer, the patient developed myocarditis combined with hepatitis. Subsequently, the patient developed pneumonia following remission from treatment. We also discuss the mechanism of irAEs, principles of treatment, and progress in the study of biomarkers for early prediction of irAEs by reviewing the literature.

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.

Case report: Complete response after transcatheter arterial chemoembolization combined with donafenib plus tislelizumab therapy for hepatocellular carcinoma with main trunk portal vein tumor thrombus in a patient coinfected with HIV and HBV

Background

Coinfection with the human immunodeficiency virus (HIV) and the hepatitis B virus (HBV) occurs in 5-67% of patients with HIV. HIV weakens the human immune system and leads to various tumors. Patients with unresectable hepatocellular carcinoma (HCC) and HIV experience poor treatment efficacy and have a short survival period. Approximately 70% of cases of HCC are diagnosed at advanced stages due to the subtle onset of the disease. As a result, most cases are not suits for curative therapy. Transcatheter arterial chemoembolization (TACE) is the first-line treatment for intermediate-stage HCC and is commonly used to treat unresectable HCC in China. Recent advancements in systemic treatments have significantly enhanced the effectiveness of unresectable HCC treatment. Several previous study showed that combination treatment combination therapy can enhance the efficacy. Notably, studies proposed that TACE combined targeted drugs with immune checkpoint inhibitors results in a high objective response rate and overall survival. However, the novelty of this study lies in its report of a complete response using a triple combination in patients with HIV and HCC with main trunk portal vein tumor thrombus.

Case presentation

A 57-year-old woman was diagnosed with HCC with a main trunk portal vein tumor thrombus combined with HIV infection, cirrhosis, and chronic viral hepatitis. She underwent TACE and was administered donafenib and tislelizumab. This triple therapy treatment regimen resulted in a clinical complete response according to the modified Response Evaluation Criteria in Solid Tumors (mRECIST) based on contrast-enhanced computed tomography.

Conclusion

We first used TACE combined with donafenib and tislelizumab for HCC patients with main trunk portal vein tumor thrombus and HIV-HBV coinfection and achieved complete response.

Review article: Contemporary management of gastrointestinal, pancreatic and hepatic toxicities of immune checkpoint inhibitors

BACKGROUND

Immune checkpoint inhibitors (ICIs) are effective oncologic agents which frequently cause immune-related adverse events (irAEs) which can impact multiple organ systems. Onco-Gastroenterology is a novel and emerging subspecialty within gastroenterology focused on cancer treatment-related complications. Gastroenterologists must be prepared to identify and manage diverse immune-mediated toxicities including enterocolitis, hepatitis, pancreatitis and other ICI-induced toxicities.

AIM

To provide a narrative review of the epidemiology, diagnostic evaluation and management of checkpoint inhibitor-induced gastrointestinal and hepatic toxicities.

METHODS

We searched Cochrane and PubMed databases for articles published through August 2023.

RESULTS

Gastrointestinal and hepatic irAEs include most commonly enterocolitis and hepatitis, but also pancreatitis, oesophagitis, gastritis, motility disorders (gastroparesis) and other rarer toxicities. Guidelines from the National Comprehensive Cancer Network, American Society of Clinical Oncology and European Society for Medical Oncology, in combination with emerging cohort and clinical trial data, offer strategies for management of ICI toxicities. Evaluation of irAEs severity by formal classification and clinical stability, and a thorough workup for alternative etiologies which may clinically mimic irAEs underlie initial management. Treatments include corticosteroids, biologics and other immunosuppressive agents plus supportive care; decisions on dosing, timing and choice of steroid adjuncts and potential for subsequent checkpoint inhibitor dosing are nuanced and toxicity-specific.

CONCLUSIONS

Expanding clinical trial and cohort data have clarified the epidemiology and clinical characteristics of gastrointestinal, pancreatic and hepatic toxicities of ICIs. Guidelines, though valuable, remain based principally on retrospective cohort data. Quality prospective, controlled studies may refine algorithms for treatment and potential immunotherapy rechallenge.

Activation of CD14+ Monocytes via the IFN-γ Signaling Pathway Is Associated with Immune-Related Adverse Events in Hepatocellular Carcinoma Patients Receiving PD-1 Inhibition Combination Therapy

(1) Background: Immune-related adverse events (irAEs) are a series of unique organ-specific inflammatory toxicities observed in patients with hepatocellular carcinoma (HCC) undergoing PD-1 inhibition combination therapy. The specific underlying mechanisms remain unclear. (2) Methods: We recruited 71 patients with HCC undergoing PD-1 inhibition combination therapy. These patients were then divided into two groups based on irAE occurrence: 34 had irAEs and 37 did not. Using Olink proteomics, we analyzed the aberrant inflammation-related proteins (IRPs) in these patient groups. For single-cell RNA sequencing (scRNA-seq) analysis, we collected peripheral blood mononuclear cells (PBMCs) from two representative patients at the pretreatment, irAE occurrence, and resolution stages. (3) Results: Our study revealed distinct plasma protein signatures in HCC patients experiencing irAEs after PD-1 inhibition combination therapy. We clarified the relationship between monocyte activation and irAEs, identified a strongly associated CD14-MC-CCL3 monocyte subset, and explored the role of the IFN-γ signaling pathway in monocyte activation during irAEs. (4) Conclusions: The activation of monocytes induced by the IFN-γ signaling pathway is an important mechanism underlying the occurrence of irAEs in HCC patients receiving PD-1 inhibition combination therapy.

Pharmacotherapy considerations in patients who develop acute kidney injury during anti-cancer therapy

INTRODUCTION

Acute kidney injury (AKI) frequently develops in patients receiving cancer therapy and requires a wide differential diagnosis due to possible role of unique cancer and drug-related factors, in addition to common pre- and post-renal causes. Rapid development of new molecular targeted anti-cancer drugs and immunotherapies has opened unprecedented possibilities of treatment at the price of an increased spectrum of renal side effects.

AREAS COVERED

The present review aims at providing a state-of-the-art picture of AKI in cancer patient (PubMed and Embase libraries were searched from inception to January 2024), with a focus on differential diagnosis and management of diverse clinical settings. Reports of parenchymal AKI due to glomerular, microvascular, tubular and interstitial damage have been constantly increasing. Complex electrolyte and acid-base disorders can coexist. The role of renal biopsy and possible therapeutic approaches are also discussed.

EXPERT OPINION

Onconephrology has become an important subspecialty of clinical nephrology, requiring constantly updated skills and a high degree of interdisciplinary integration to tackle diagnostic challenges and even therapeutic and ethical dilemmas. Integrated onconephrological guidelines and availability of biomarkers may provide new tools for management of this unique type of patients in the near future.

Allulose mitigates chronic enteritis by reducing mitochondria dysfunction via regulating cathepsin B production

Metabolic changes have been linked to the development of inflammatory bowel disease (IBD), which includes colitis. Allulose, an endogenous bioactive monosaccharide, is vital to the synthesis of numerous compounds and metabolic processes within living organisms. Nevertheless, the precise biochemical mechanism by which allulose inhibits colitis remains unknown. Allulose is an essential and intrinsic protector of the intestinal mucosal barrier, as it maintains the integrity of tight junctions in the intestines, according to the current research. It is also important to know that there is a link between the severity of inflammatory bowel disease (IBD) and colorectal cancer (CRC), chemically-induced colitis in rodents, and lower levels of allulose in the blood. Mice with colitis, either caused by dextran sodium sulphate (DSS) or naturally occurring colitis in IL-10-/- mice, had less damage to their intestinal mucosa after being given allulose. Giving allulose to a colitis model starts a chain of reactions because it stops cathepsin B from ejecting and helps lysosomes stick together. This system effectively stops the activity of myosin light chain kinase (MLCK) when intestinal epithelial damage happens. This stops the breakdown of tight junction integrity and the start of mitochondrial dysfunction. To summarise, the study's findings have presented data that supports the advantageous impact of allulose in reducing the advancement of colitis. Its ability to stop the disruption of the intestinal barrier enables this. Therefore, allulose has potential as a medicinal supplement for treating colitis.

Clinical Management of Gastrointestinal and Liver Toxicities of Immune Checkpoint Inhibitors

Immune checkpoint inhibitors have transformed the treatment paradigm for various types of cancer. Nonetheless, with the utilization of these groundbreaking treatments, immune-related adverse events (irAEs) are increasingly encountered. Colonic and hepatic involvement are among the most frequently encountered irAEs. Drug-induced side effects, infectious causes, and tumor-related symptoms are the key differentials for irAE complications. Potential risk factors for the development of irAEs include combination use of immune checkpoint inhibitors, past development of irAEs with other immunotherapy treatments, certain concomitant drugs, and a pre-existing personal or family history of autoimmune illness such as inflammatory bowel disease. The importance of early recognition, timely and proper management cannot be understated, as there are profound clinical implications on the overall cancer treatment plan and prognosis once these adverse events occur. Herein, we cover the clinical management of the well-established gastrointestinal irAEs of enterocolitis and hepatitis, and also provide an overview of several other emerging entities.

Targeted delivery of Fc-fused PD-L1 for effective management of acute and chronic colitis

The PD-1/PD-L1 pathway in mucosal immunity is currently actively explored and considered as a target for inflammatory bowel disease (IBD) treatment. However, systemic PD-L1 administration may cause unpredictable adverse effects due to immunosuppression. Here we show that reactive oxygen species (ROS)-responsive nanoparticles enhance the efficacy and safety of PD-L1 in a mouse colitis model. The nanoparticles control the accumulation and release of PD-L1 fused to Fc (PD-L1-Fc) at inflammatory sites in the colon. The nanotherapeutics shows superiority in alleviating inflammatory symptoms over systemic PD-L1-Fc administration and mitigates the adverse effects of PD-L1-Fc administration. The nanoparticles-formulated PD-L1-Fc affects production of proinflammatory and anti-inflammatory cytokines, attenuates the infiltration of macrophages, neutrophils, and dendritic cells, increases the frequencies of Treg, Th1 and Tfh cells, reshapes the gut microbiota composition; and increases short-chain fatty acid production. In summary, PD-L1-Fc-decorated nanoparticles may provide an effective and safe strategy for the targeted treatment of IBD.

Targeted therapy or immunotherapy in BRAF-mutated metastatic melanoma: a Spanish center's decade of experience

Background

Targeted therapies and immunotherapy are currently considered the mainstay first-line treatment for advanced BRAF-mutated melanoma. However, the impact of treatment (targeted therapy and immunotherapy) and the prognostic factors are still not clear.

Material and methods

Medical records of 140 patients diagnosed with advanced melanoma between 2011 and 2021 were retrospectively reviewed to extract demographic, BRAF status, treatment, performance status, and survival data. ORR, PFS, and OS were compared between patients diagnosed with advanced melanoma and treated with first-line IT or BRAF/MEKi. The prognostic factors were assessed using Cox regression models.

Results

In all patients and those treated with immunotherapy, we did not find any effect of BRAF status on ORR, PFS, or OS. In patients with BRAF-mutated melanoma, ORR was 43.8% vs. 70% (P=0.04), PFS was 19.2 vs. 11.5 months (p=0.22), and OS was 33.4 vs. 16.4 months for the immunotherapy and targeted therapy groups, respectively (P=0.04). ECOG, presence of brain metastases, and high LDH level from initiation of first-line treatment were all associated with differences in PFS and OS.

Conclusion

Patients with advanced BRAF-mutated melanoma treated with first-line immunotherapy had a significantly longer PFS and OS than those treated with first-line BRAF/MEKi; however, first-line BRAF/MEKi treatment had a significantly higher ORR than first-line immunotherapy.

Combined Immunotherapy Improves Outcome for Replication-Repair-Deficient (RRD) High-Grade Glioma Failing Anti-PD-1 Monotherapy: A Report from the International RRD Consortium

Immune checkpoint inhibition (ICI) is effective for replication-repair-deficient, high-grade gliomas (RRD-HGG). The clinical/biological impact of immune-directed approaches after failing ICI monotherapy is unknown. We performed an international study on 75 patients treated with anti-PD-1; 20 are progression free (median follow-up, 3.7 years). After second progression/recurrence (n = 55), continuing ICI-based salvage prolonged survival to 11.6 months (n = 38; P < 0.001), particularly for those with extreme mutation burden (P = 0.03). Delayed, sustained responses were observed, associated with changes in mutational spectra and the immune microenvironment. Response to reirradiation was explained by an absence of deleterious postradiation indel signatures (ID8). CTLA4 expression increased over time, and subsequent CTLA4 inhibition resulted in response/stable disease in 75%. RAS-MAPK-pathway inhibition led to the reinvigoration of peripheral immune and radiologic responses. Local (flare) and systemic immune adverse events were frequent (biallelic mismatch-repair deficiency > Lynch syndrome). We provide a mechanistic rationale for the sustained benefit in RRD-HGG from immune-directed/synergistic salvage therapies. Future approaches need to be tailored to patient and tumor biology.

SIGNIFICANCE

Hypermutant RRD-HGG are susceptible to checkpoint inhibitors beyond initial progression, leading to improved survival when reirradiation and synergistic immune/targeted agents are added. This is driven by their unique biological and immune properties, which evolve over time. Future research should focus on combinatorial regimens that increase patient survival while limiting immune toxicity. This article is featured in Selected Articles from This Issue, p. 201.

Diagnosis and Pharmacological Management of Microscopic Colitis in Geriatric Care

Microscopic colitis, a diagnosis under the umbrella term of inflammatory bowel disease, is a prevalent cause of watery diarrhea, often with symptoms of urgency and bloating, typically observed in older adults aged ≥ 60 years. Its incidence has been reported to exceed those of ulcerative colitis and Crohn's disease in some geographical areas. Although nonpathognomonic endoscopic abnormalities, including changes of the vascular mucosal pattern; mucosal erythema; edema; nodularity; or mucosal defects, e.g., "cat scratches" have been reported, a colonoscopy is typically macroscopically normal. As reliable biomarkers are unavailable, colonoscopy using random biopsies from various parts of the colon is compulsory. Based on the histological examination under a microscope, the disease is divided into collagenous (with a thickened subepithelial collagenous band) and lymphocytic (with intraepithelial lymphocytosis) colitis, although incomplete forms exist. In routine clinical settings, the disease has a high risk of being misdiagnosed as irritable bowel syndrome or even overlooked. Therefore, healthcare providers should be familiar with clinical features and rational management strategies. A 6-8-week oral budesonide treatment course (9 mg/day) is considered the first-line therapy, but patients often experience relapse when discontinued, or might become intolerant, dependent, or even fail to respond. Consequently, other therapeutic options (e.g., bismuth subsalicylate, biologics, loperamide, bile acid sequestrants, and thiopurines) recommended by available guidelines may be prescribed. Herein, clinically meaningful data is provided based on the latest evidence that may aid in reaching a diagnosis and establishing rational therapy in geriatric care to control symptoms and enhance the quality of life for those affected.

The JAK-STAT Pathway as a Therapeutic Strategy in Cancer Patients with Immune Checkpoint Inhibitor-Induced Colitis: A Narrative Review

Immunotherapy has emerged as a pivotal component in the treatment of various malignancies, encompassing lung, skin, gastrointestinal, and head and neck cancers. The foundation of this therapeutic approach lies in immune checkpoint inhibitors (ICI). While ICIs have demonstrated remarkable efficacy in impeding the neoplastic progression of these tumours, their use may give rise to substantial toxicity, notably in the gastrointestinal domain, where ICI colitis constitutes a significant aspect. The optimal positioning of Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway inhibitors in the therapeutic management of ICI colitis remains unclear. Numerous reports have highlighted notable improvements in ICI colitis through the application of pan-JAK-STAT inhibitors, with tofacitinib, in particular, reporting evident clinical remission of colitis. The precise mechanism by which JAK-STAT inhibitors may impact the pathogenetic process of ICI colitis remains inadequately understood. However, there is speculation regarding their potential role in modulating memory resident CD8+ T lymphocytes. The elucidation of this mechanism requires further extensive and robust evidence, and ongoing JAK-STAT-based trials are anticipated to contribute valuable insights.

Severe Dysphagia With Eosinophilic Esophagitis Pattern of Injury Related to Pembrolizumab Therapy

While immune checkpoint inhibitor (ICI) therapies are effective treatments for many cancers, ICI therapies are associated with immune-related adverse events. We present a 67-year-old man with non-small cell lung carcinoma, who developed severe dysphagia with biopsies from an esophagogastroduodenoscopy showing histopathology consistent with eosinophilic esophagitis while on ICI maintenance therapy with pembrolizumab. The patient's symptoms worsened despite standard therapy. However, he had complete resolution of dysphagia symptoms once pembrolizumab was discontinued. While immune-related adverse events affecting the gastrointestinal system are increasingly recognized, ICI-associated eosinophilic esophagitis is a rare entity.

A Systematic Review of Treatment-Related Adverse Events for Combination Therapy of Multiple Tyrosine Kinase Inhibitor and Immune Checkpoint Inhibitor

BACKGROUND

Combination therapy with multiple tyrosine kinase inhibitors (multi-TKIs) and immune checkpoint inhibitors (ICIs) has been increasingly tested in clinical studies. This study aimed to investigate the effect of the addition of ICI to multi-TKIs on the profile of treatment-related adverse events.

METHODS

An electronic database search was performed using PubMed and Web of Science to identify published clinical studies on multi-TKI monotherapy and multi-TKI plus ICI combination therapy from July 20, 2005 to July 1, 2023. The incidence rate of common adverse events caused by multi-TKI monotherapy and multi-TKI plus ICI combination therapy was obtained and compared from the viewpoints of (1) relative risk for the combination therapy vs sunitinib, (2) adverse event incidence rate by clinical trial, and (3) pooled incidence rate. The quality of the evidence was assessed with the Cochrane risk of bias tool. Meta-analysis used random effects models.

RESULTS

This systematic review identified 83 clinical studies involving 7951 patients. The combination therapy of multi-TKI and ICI was associated with an increased risk of diarrhea (relative risk [RR]: 1.24, 95% confidence interval [CI]: 1.15-1.33, P < .001), hypothyroidism (RR: 1.44, 95% CI: 1.11-1.87, P = .0064) and rash (RR: 1.71, 95% CI: 1.18-2.47, P = .0045) compared with multi-TKI monotherapy. The addition of ICI was suggested to decrease the risk of adverse events related to performance status.

CONCLUSION

Our study identified an increased risk of treatment-related adverse events associated with multi-TKI plus ICI combination therapy. This would help optimize the management of toxicities caused by multi-TKI plus ICI combination therapy.

The colitis may be microscopic, but the diarrhea is not: update on the treatment of microscopic colitis and immune checkpoint inhibitor colitis

PURPOSE OF REVIEW

Microscopic colitis is an inflammatory disease of the colon that presents as watery diarrhea with minimal to normal endoscopic changes on colonoscopy. It encompasses two common subtypes, lymphocytic colitis and collagenous colitis, which are both treated similarly.Immune checkpoint inhibitor colitis is among the most common immune-related adverse events. Endoscopic and histological findings range from normal colonic mucosa to inflammatory bowel like changes. This review article provides update in treatment and management of microscopic colitis and immune checkpoint inhibitor colitis (ICPi colitis).

RECENT FINDINGS

Recent studies on microscopic colitis have focused on the successful use of immunomodulators such as biologics for treatment of budesonide refractory microscopic colitis cases. Microscopic colitis does not confer an added risk for colorectal cancer.With the increasing usage of immunotherapy agents, immune checkpoint inhibitor colitis is becoming more common. ICPi colitis can be successfully managed with steroids, with treatment stepped up to biologics for moderate to severe cases or for mild cases that do not respond to steroids. Immunotherapy agents can be carefully re-introduced in mild cases, after treatment of ICPi colitis.

SUMMARY

Biologics can be used to treat budesonide refractory microscopic colitis. ICPi colitis can be managed with steroids and biologics in moderate to severe cases.

DECTIN-1: A modifier protein in CTLA-4 haploinsufficiency

Autosomal dominant loss-of-function (LoF) variants in cytotoxic T-lymphocyte associated protein 4 (CTLA4) cause immune dysregulation with autoimmunity, immunodeficiency and lymphoproliferation (IDAIL). Incomplete penetrance and variable expressivity are characteristic of IDAIL caused by CTLA-4 haploinsufficiency (CTLA-4h), pointing to a role for genetic modifiers. Here, we describe an IDAIL proband carrying a maternally inherited pathogenic CTLA4 variant and a paternally inherited rare LoF missense variant in CLEC7A, which encodes for the β-glucan pattern recognition receptor DECTIN-1. The CLEC7A variant led to a loss of DECTIN-1 dimerization and surface expression. Notably, DECTIN-1 stimulation promoted human and mouse regulatory T cell (Treg) differentiation from naïve αβ and γδ T cells, even in the absence of transforming growth factor-β. Consistent with DECTIN-1's Treg-boosting ability, partial DECTIN-1 deficiency exacerbated the Treg defect conferred by CTL4-4h. DECTIN-1/CLEC7A emerges as a modifier gene in CTLA-4h, increasing expressivity of CTLA4 variants and acting in functional epistasis with CTLA-4 to maintain immune homeostasis and tolerance.

Serious immune-related upper gastrointestinal toxicity of immune checkpoint inhibitors: a multicenter case series

BACKGROUND

Immune checkpoint inhibitors (ICI) improve the prognosis of many cancers but cause immune-related adverse events (IrAEs). Limited data are available on upper gastrointestinal (UGI) IrAEs. We describe the clinical characteristics, prognosis, and efficacy of medical therapy in patients with UGI IrAEs.

METHODS

This is a retrospective, multicenter cohort study of patients with UGI symptoms and moderate to severe endoscopic UGI lesions, occurring after ICI. Efficacy of induction medical therapy and at the most recent follow-up was assessed.

RESULTS

Forty patients were included; of these, 34 (85%) received anti-PD(L)1, either alone (n = 24) or combined with anti CTLA-4 (n = 10). Eighteen patients (45%) had concomitant enterocolitis. All patients had severe endoscopic lesions (erosions, ulcerations, hemorrhage, or necrotic lesions). Three patients who received an inefficient initial medical treatment had a complicated course: One patient died of enterocolitis, one had a pneumomediastinum, and one developed an ulcerated stricture of the pylorus. Thirty-five patients (88%) were treated with corticosteroids; 28 patients (80%) responded, and 20 (57%) reached clinical remission. Eight patients were treated with infliximab, and six responded (75%). After a median follow-up of 11 months, 36 patients (90%) were in corticosteroid-free clinical remission for their UGI symptoms. Endoscopic lesions persisted in 68% of patients.

CONCLUSIONS

ICI cause severe UGI IrAEs, which are associated with enterocolitis in approximately half of the patients. Most patients with UGI IrAEs respond to corticosteroids or infliximab. These data support the recommendation to treat these patients without delay and in the same way as those with enterocolitis.

IL12/23 Blockade with Ustekinumab as a Treatment for Immune-Related Cutaneous Adverse Events

Background: Immune-related cutaneous adverse events (ircAEs) are frequent and may reduce quality of life and consistent dosing. IL12/23 has been implicated in psoriasis, which is reminiscent of the psoriasiform/lichenoid ircAE phenotype. We report the use of ustekinumab as a therapeutic option. Methods: Patients at Memorial Sloan Kettering Cancer Center, New York, who received immune checkpoint inhibitors and were treated with ustekinumab or had the keywords "ustekinumab" or "Stelara" in their clinical notes between 1 March 2017 and 1 December 2022 were retrospectively identified via a database query. Documentation from initial and follow-up visits was manually reviewed, and response to ustekinumab was categorized into complete cutaneous response (CcR, decrease to CTCAE grade 0), partial cutaneous response (PcR, any decrease in CTCAE grade exclusive of decrease to grade 0), and no cutaneous response (NcR, no change in CTCAE grade or worsening). Labs including complete blood count (CBC), cytokine panels, and IgE were obtained in a subset of patients as standard of care. Skin biopsies were reviewed by a dermatopathologist. Results: Fourteen patients with psoriasiform (85.7%), maculopapular (7.1%), and pyoderma gangrenosum (7.1%) ircAEs were identified. Ten (71.4%) receiving ustekinumab had a positive response to treatment. Among these 10 responders, 4 (40%) demonstrated partial cutaneous response and 6 (60%) demonstrated complete cutaneous resolution. Six patients (42.9%) experienced interruptions to their checkpoint inhibitor treatment as a result of intolerable ircAEs, and following ircAE management with ustekinumab, two (33.3%) were successfully rechallenged with their checkpoint inhibitors. On histopathology, patients primarily had findings of interface or psoriasiform dermatitis. No patients reported an adverse event related to ustekinumab. Conclusions: Ustekinumab showed a benefit in a subset of patients with psoriasiform/lichenoid ircAEs. No safety signals were identified. However, further prospective randomized controlled trials are needed to confirm our findings.

T Cell Invigoration is Associated with the Clinical Response to Anti-PD-1-Based Immunotherapy in Non-Small Cell Lung Cancer

Purpose

Immune checkpoint inhibitors (ICIs) have been developed for clinical application and proven effective for non-small cell lung cancer (NSCLC). Blockade of the programmed cell death 1 (PD-1) protein can partially reinvigorate circulating exhausted-phenotype CD8+ T cells (Tex cells) in preclinical models, however the clinical implication in anti-PD-1-based immunotherapy in NSCLC is unknown.

Methods

Serum specimens were obtained before and during treatment from 145 patients with NSCLC patients who received anti-PD-1 treatment and their prognoses were followed-up. Indicators such as cell subpopulations, T cell invigoration were detected by clinical laboratory testing. Survival curves were estimated by the Kaplan-Meier method, Cox regression analysis was used to identify factors associated with prognoses of NSCLC patients.

Results

The expressions of Ki-67 in PD-1+/CD8+ T cells in most NSCLC patients (97 of 145 cases) increased after treatment. The responding Ki-67+/CD8+ T cell population was mainly CD45RAlo CD27hi, containing cells with high expression of CTLA-4, PD-1, and 2B4 and low expression of NKG2-D (P < 0.0001). The maximum fold change of Ki-67+/PD-1+/CD8+T cells in treatment cycles and the tumor burden determined by imaging may be associated with survival. Patients with higher Ki-67 expression on PD-1+CD8+ T-cells (pretreatment) had statistically significant increased progression-free survival (PFS). A Ki-67 expression to tumor burden ratio greater than 0.6 at the 1st cycle of anti-PD-1 immunotherapy was associated with improvement of PFS and overall survival (P < 0.05).

Conclusion

Activation of circulating Tex cells before or during therapy related to tumor burden may be associated with clinical efficacy of anti-PD-1 immune therapy in NSCLC.

Gut microbiome on immune checkpoint inhibitor therapy and consequent immune-related colitis: a review

Immune checkpoint inhibitors have dramatically revolutionized the therapeutic landscape for patients with advanced malignancies. Recently, convincing evidence has shown meaningful influence of gut microbiome on human immune system. With the complex link between gut microbiome, host immunity and cancer, the variations in the gut microbiota may influence the efficacy of immune checkpoint inhibitors. Indeed, some bacterial species have been reported to be predictive for cancer outcome in patients treated with immune checkpoint inhibitors. Although immune checkpoint inhibitors are currently proven to be an effective anti-tumor treatment, they can induce a distinct form of toxicity, termed immune-related adverse events. Immune-related colitis is one of the common toxicities from immune checkpoint inhibitors, and it might preclude the cancer therapy in severe or refractory cases. The manipulation of gut microbiome by fecal microbiota transplantation or probiotics administration has been suggested as one of the methods to enhance anti-tumor effects and decrease the risk of immune-related colitis. Here we review the role of gut microbiome on immune checkpoint inhibitor therapy and consequent immune-related colitis to provide a new insight for better anti-cancer therapy.

Vedolizumab as Rescue Therapy in Carboplatin-Gemcitabine-Induced Triggered Acute Severe Ulcerative Colitis Flare-Up

Approximately 20% of patients with ulcerative colitis (UC) develop acute severe UC (ASUC), for which intravenous systemic steroid therapy and possibly infliximab-based rescue therapy are generally imposed. However, there are no significant guideline recommendations on ASUC regarding vedolizumab as an alternative in this setting. A case report was presented where a patient with steroid-dependent UC developed ASUC induced by second-line chemotherapy. Treatment with intravenous methylprednisolone was imposed, but there was no reduction in bowel movements in the days following admission. Rescue therapy with infliximab was contraindicated because of the oncologic history. Surgical consultation, contraindicated colectomy, and administration of vedolizumab 300 mg were initiated. After infusion with vedolizumab, there was a significant reduction in bowel movements starting the day after infusion until normalisation of bowel movements within three days and the concomitant normalisation of inflammatory indices. The patient is currently in clinical remission, on therapy with vedolizumab 108 mg subcutaneously every two weeks, and is in oncologic follow-up for pulmonary neoplasm. This case highlights the novel potential of vedolizumab as a possible rescue therapy in ASUC, especially in special populations, where it may offer a better safety profile. Although cyclosporine and infliximab still represent the mainstays of salvage therapy for steroid-refractory ASUC, new therapeutic agents may also be effective, such as vedolizumab, ustekinumab, and anti-Janus kinase agents.

Abnormal generation of IL-17A represses tumor infiltration of stem-like exhausted CD8+ T cells to demote the antitumor immunity

BACKGROUND

Variated anti-cancer therapies are combined with immune checkpoint blockades (ICBs) for improving ICB therapeutic efficacy. Occurrence of tissue damage is common that triggers multiple inflammatory cytokine generation. Gastrointestinal organs are the commonly affected. We investigated the impact of acute colitis on tumor infiltration of antigen-specific CD8+ cytotoxic T lymphocytes (CTLs) for controlling tumor growth and responding to antibody against PD-1 (anti-PD-1).

METHODS

Several tumor cell lines were inoculated into syngeneic mice subcutaneously or intra-hepatically. When tumor mass formed, activated CTLs were intravenously transferred into the tumor-bearing mice, that were given the drinking water containing 2% dextran sulfate sodium (DSS) for acute colitis induction. Tumor growth, infiltration of two exhausted CTL subsets, and the CTL interaction with tumor vascular endothelium were examined.

RESULTS

Acute colitis dampened CTL-mediated antitumor effects, correlating with IL-17A elevation in the inflamed intestine. In the tumor bed, stem-like exhausted CTLs, which were defined as PD-1+Slamf6+Tim3-, expressed higher IL-17A receptor heterodimers and lower leukocyte function-associated antigen-1 (LFA-1) than terminally exhausted CTLs did, that were defined as PD-1+Slamf6-Tim3+. IL-17A stimulation reduced LFA-1 surface expression on stem-like exhausted CTLs and the counterpart ICAM-1 (intracellular adhesion molecule-1) on tumor vascular endothelium. IL-17A stimulation suppressed the extravasation across tumor vascular endothelium and self-renewal of stem-like, not the terminally exhausted CTLs. Administration of anti-IL-17A neutralizing antibody to the colitis mice restored the CTL tumor infiltration and enhanced anti-PD-1 treatment efficacy against tumors. In 33 hepatocellular carcinoma patients being treated with anti-PD-1 plus antibody against vascular endothelial growth factor, disease progression of 15 patients, that exhibited serum IL-17A increase 24 h post-therapy as compared to pre-therapy level, was poorer than that of 18 patients that exhibited serum IL-17A no-increase.

CONCLUSIONS

Abnormal generation of IL-17A mainly repressed tumor infiltration of stem-like exhausted CTLs. ICB-based immunotherapeutic efficacy could be upgraded with administration of anti-IL-17A, when treatment-related IL-17A elevation occurred due to tissue damage, such as acute colitis.

Characteristics and outcomes of cancer patients with pre-existing microscopic colitis after exposure to PD-1 and PD-L1 inhibitors

PURPOSE

Immune checkpoint inhibitors (ICIs) are frequently associated with adverse events, often affecting the gastrointestinal tract. We conducted this study to determine the characteristics and outcomes of cancer patients with pre-existing microscopic colitis (MC) who underwent ICI treatment.

METHODS

In this retrospective study, we identified 10 patients with pre-existing MC who received ICIs at our center 01/2010-06/2020. Clinical characteristics and disease outcomes were recorded.

RESULTS

Of 124 screened patients with MC before ICI exposure, 10 had sufficient data to be included in the study. Melanoma (40%) and lung cancer (30%) were the most prevalent cancer types, with 70% of stage IV cancer. Patients received either anti-programmed death 1 regimen (8, 80%) or anti-programmed death ligand 1 agent (2, 20%). Six patients (60%) had collagenous colitis, and 4 (40%) had lymphocytic colitis. The median time from MC diagnosis to ICI initiation was 4 years, with 1 patient on budesonide within 2 months of ICI initiation. Eight patients (80%) developed colitis exacerbations after ICI  and required selective immunosuppression. One patient received a compassionate-use fecal transplantation. The median time from ICI to colitis exacerbation was 14 days, with 40% and 50% of patients experiencing grade 3 diarrhea and grade 2 colitis, respectively, leading to hospitalization in 3 patients. Six patients received steroids and vedolizumab with no colitis recurrence. Of 8 patients who had colitis exacerbation, 6 resumed ICI therapy afterward; with 5 receiving concomitant vedolizumab for secondary prophylaxis.

CONCLUSION

Our findings suggest that ICI exposure increases the risk of exacerbation of underlying colitis necessitating and responding to potent immunosuppression therapy.

Microscopic Colitis: Pathogenesis and Diagnosis

Microscopic colitis is a type of inflammatory bowel disease and is classified as either collagenous colitis or lymphocytic colitis. The typical presentation is chronic watery diarrhea. The disease occurs more frequently in women aged 60-65 years and is increasing in incidence. The pathophysiology of microscopic colitis remains poorly understood and has not been well-described with possible several pathogeneses. To date, the diagnosis of microscopic colitis depends on histological tissue obtained during colonoscopy. Other non-invasive biomarkers, such as inflammatory markers and fecal biomarkers, have been studied in microscopic colitis, but the results remains inconclusive. The approach to chronic diarrhea is important and being able to differentiate chronic diarrhea in patients with microscopic colitis from other diseases, such as inflammatory bowel disease, functional diarrhea, and malignancy, by using non-invasive biomarkers would facilitate patient management. The management of microscopic colitis should be based on each individual's underlying pathogenesis and involves budesonide, bile acid sequestrants, or immunosuppressive drugs in refractory cases. Cigarette smoking and certain medications, especially proton pump inhibitors, should be eliminated, when possible, after the diagnosis is made.

Oncolytic Virus-Driven Biotherapies from Bench to Bedside

With advances in cancer biology and an ever-deepening understanding of molecular virology, oncolytic virus (OV)-driven therapies have developed rapidly and become a promising alternative to traditional cancer therapies. In recent years, satisfactory results for oncolytic virus therapy (OVT) are achieved at both the cellular and organismal levels, and efforts are being increasingly directed toward clinical trials. Unfortunately, OVT remains ineffective in these trials, especially when performed using only a single OV reagent. In contrast, integrated approaches, such as using immunotherapy, chemotherapy, or radiotherapy, alongside OVT have demonstrated considerable efficacy. The challenges of OVT in clinical efficacy include the restricted scope of intratumoral injections and poor targeting of intravenous administration. Further optimization of OVT delivery is needed before OVs become a viable therapy for tumor treatment. In this review, the development process and antitumor mechanisms of OVs are introduced. The advances in OVT delivery routes to provide perspectives and directions for the improvement of OVT delivery are highlighted. This review also discusses the advantages and limitations of OVT monotherapy and combination therapy through the lens of recent clinical trials and aims to chart a course toward safer and more effective OVT strategies.

Checkpoint Inhibitor-Induced Colitis: An Update

Immunotherapy with immune checkpoint inhibitors (ICIs) nowadays has indications for several solid tumors. The current targets for ICIs are CTLA-4, PD-1, and PD-L1 receptors. Despite the clinical advantages derived from ICIs, a variety of side effects are linked to overstimulation of the immune system. Among these, ICI-related colitis is one of the most common, with a disabling impact on the patient. Diarrhea, abdominal pain, abdominal distension, cramping, and hematochezia are the most common ICI enterocolitis presenting symptoms. The most frequently used grading system for assessment of the severity of ICI enterocolitis is called the Common Terminology Criteria for Adverse Events (CTCAE) grading. With regard to the histological picture, there is no specific feature; however, microscopic damage can be classified into five types: (1) acute active colitis, (2) chronic active colitis, (3) microscopic colitis-like, (4) graft-versus-host disease-like, and (5) other types. Supportive therapy (oral hydration, a bland diet without lactose or caffeine, and anti-diarrheal agents) is indicated in mild colitis. Symptomatic treatment alone or with loperamide, a low-fiber diet, and spasmolytics are recommended for low-grade diarrhea. In more severe cases, corticosteroid treatment is mandatory. In refractory cases, off-label use of biological therapies (infliximab or vedolizumab) was proposed.

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.

Immunotherapies for advanced hepatocellular carcinoma

Primary liver cancer is the second leading cause of tumor-related deaths in China, with hepatocellular carcinoma (HCC) accounting for 80%-90% of these. Since there is a lack of symptoms in the early stages of HCC, a large proportion of patients were identified with unresectable HCC when diagnosed. Due to the severe resistance to chemotherapy, patients with advanced HCC were traditionally treated with systematic therapy in the past decades, and the tyrosine kinase inhibitor (TKI) sorafenib has remained the only treatment option for advanced HCC since 2008. Immunotherapies, particularly immune checkpoint inhibitors (ICIs), have shown a strong anti-tumor effect and have been supported by several guidelines recently. ICIs, for example programmed cell death-1 (PD-1) inhibitors such as nivolumab and pembrolizumab, programmed cell death ligand 1 (PD-L1) inhibitors such as atezolizumab, and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) inhibitors such as ipilimumab, the ICI-based combination with TKIs, and VEGF-neutralizing antibody or systematic or local anti-tumor therapies, are being further studied in clinical trials. However, immune-related adverse events (irAEs) including cutaneous toxicity, gastrointestinal toxicity, and hepatotoxicity may lead to the termination of ICI treatment or even threaten patients' lives. This review aims to summarize currently available immunotherapies and introduce the irAEs and their managements in order to provide references for clinical application and further research.