Immune Checkpoint Blockade and Skin Toxicity Pathogenesis

Dermatologic toxicities related to cancer immunotherapy

Immunotherapy has revolutionized cancer treatment, offering significant survival superiority for advanced malignancies. However, immunotherapy is associated with various immune-related adverse events, one of the most common of them being dermatologic toxicities. Previous studies have reported dermatologic adverse events in almost half of the cancer patients undergoing immunotherapy. The spectrum of dermatologic toxicities ranges from mild, self-limiting reactions to severe, life-threatening conditions, and includes maculopapular rash, pruritus, vitiligo-like depigmentation, psoriasiform eruption, lichenoid eruption, bullae, photosensitivity, hair loss, nail changes, Stevens-Johnson syndrome, and toxic epidermal necrolysis. The management strategies are based on personalized treatment plans, multidisciplinary approaches, and timely therapeutic interventions aimed at addressing dermatologic toxicities while preserving immunotherapy efficacy. Based on the latest findings, this paper offers a novel perspective and provides an evidence-based review of the pathogenesis, manifestations, incidence, grading, clinical management, and prognostic significance of these toxicities, underlining the importance of balancing the efficacy of immunotherapy with timely and proactive management of their dermatological toxicities to enhance patient outcomes and quality of life.

Autoimmune-related adverse events induced by immune checkpoint inhibitors

Targeted immunotherapies, particularly immune checkpoint inhibitors (ICIs), have transformed cancer treatment by significantly improving patient response and survival rates. However, ICIs could disrupt self-tolerance, inducing the development of immune-related adverse events (irAEs). Most irAEs are classified as autoimmune conditions mediated by ICI-activated CD8+ cytotoxic T cells or activated B cells producing pathogenic autoantibodies. These irAEs phenotypically resemble spontaneous autoimmune disease and lead to considerable morbidity, health care costs, and compromised treatment efficacy. With the widespread use and new emergence of ICIs, the spectrum of ICI-induced irAEs has become increasingly extensive and complex. Concurrently, research in this field is advancing rapidly, a review summarizing the latest progress on irAEs is timely and essential. In this review, we highlight numerous recent research advances, covering the epidemiology, immune mechanisms, and diverse manifestations of irAEs, with a particular focus on organ-specific autoimmunity. We also discuss current strategies, challenges, and future directions for the prevention and therapeutic management of these adverse events.

Multiple mechanisms and applications of tertiary lymphoid structures and immune checkpoint blockade

BACKGROUND

Immune checkpoint blockade (ICB) inhibits tumor immune escape and has significantly advanced tumor therapy. However, ICB benefits only a minority of patients treated and may lead to many immune-related adverse events. Therefore, identifying factors that can predict treatment outcomes, enhance synergy with ICB, and mitigate immune-related adverse events is urgently needed.

MAIN TEXT

Tertiary lymphoid structures (TLS) are ectopic lymphoid tissues that arise from the tumor periphery. They have been found to be associated with better prognosis and improved clinical outcomes after ICB therapy. TLS may help address the problems associated with ICB. The multiple mechanisms of action between TLS and ICB remain unknown. This paper described potential mechanisms of interaction between the two and explored their potential applications.

Severe cutaneous drug toxicity following disitamab vedotin treatment for metastatic gastric cancer: a case report

Background

This study reports a case of severe cutaneous toxicity in a patient with metastatic gastric cancer induced by disitamab vedotin, emphasizing the need for careful monitoring and management in such treatments.

Case presentation

A 71-year-old female was admitted to hospital complaining of serious rashes following the first cycle of disitamab vedotin regimen for metastatic gastric cancer. The doctor diagnosedtoxic epidermal necrolysis (TEN) induced by the drug. The patient received high-dose methylprednisolone due to the side effects. This resulted in a gradual improvement of symptoms.

Conclusion

During the use of disitamab vedotin, patients need to be monitored for severe skin toxicity.

Cutaneous adverse events due to checkpoint inhibitors - a retrospective analysis at a tertiary referral hospital in Switzerland 2019-2022

Introduction

Checkpoint inhibitors are increasingly important in anti-cancer treatment. Therefore, knowledge of immune-related cutaneous adverse events (ir-cAE) is crucial for therapy management and continuation.

Objective

The study aimed to analyze the incidence of cutaneous adverse events caused by checkpoint inhibitor therapy, including their clinical presentation, management, and impact on further treatment.

Methods

This is a descriptive, monocentric retrospective study that uses data from the electronic health record system at a tertiary referral hospital in Central Switzerland from September 2019 to September 2022. The electronic health records of patients who received a therapy with checkpoint inhibitors were examined for age, sex, type of immunotherapy, time to occurrence of ir-cAEs, characteristics of the ir-cAEs, the treatment approach, and the continuation or cessation of the therapy due to ir-cAEs.

Results

Out of 431 patients, for 131 patients (30.4%) at least one ir-cAE event was documented. In particular, 109 (25.3%) experienced pruritus and 61 (14.2%) showed a maculopapular exanthema. The severity of the ir-cAE was mild in 88 patients (67.2% out of those with ir-cAEs). Ir-cAE were observed in 10 out of 20 patients (50%) treated with ipilimumab/nivolumab and in 15 out of 24 (62.5%) treated with durvalumab. In 15 patients (3.5%), checkpoint inhibitor therapy had to be discontinued due to cutaneous side effects.

Conclusions

This study showed that approximately one third of the patients experienced ir-cAEs. The most frequently observed ir-cAEs were pruritus, maculopapular exanthema and xerosis cutis. In general, the dermatological manifestations are mild and responsive to topical treatment or self-limiting with no requirement for treatment interruption.

Immune checkpoint inhibitor-induced bullous pemphigoid is characterized by interleukin (IL)-4 and IL-13 expression and responds to dupilumab treatment

Immune checkpoint inhibitor-induced bullous pemphigoid (ICI-BP) is a clinically debilitating immune-related adverse event in need of novel therapeutic approaches, as conventional treatment can counteract intended tumour immunity. Here we demonstrate that interleukin (IL)-4 and IL-13 expression is elevated in ICI-BP similar to conventional autoimmune BP, and further demonstrate partial and complete disease clearance with dupilumab in four patients with ICI-BP. These data indicate that IL-4Rα inhibition may be a promising new therapy for ICI-BP.

Current status of skin cancers with a focus on immunology and immunotherapy

Skin cancer is one of the most widespread cancers, with a significant global health effect. UV-induced DNA damage in skin cells triggers them to grow and proliferate out of control, resulting in cancer development. Two common types of skin cancer include melanoma skin cancer (MSC) and non-melanoma skin cancer (NMSC). Melanoma is the most lethal form of skin cancer, and NMSC includes basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and other forms. The incidence of skin cancer is increasing in part owing to a demographic shift toward an aging population, which is more prone to NMSC, imposing a considerable financial strain on public health services. The introduction of immunostimulatory approaches for cancer cell eradication has led to significant improvements in skin cancer treatment. Over the last three decades, monoclonal antibodies have been used as powerful human therapeutics besides scientific tools, and along with the development of monoclonal antibody production and design procedures from chimeric to humanized and then fully human monoclonal antibodies more than 6 monoclonal antibodies have been approved by the food and drug administration (FDA) and have been successful in skin cancer treatment. In this review, we will discuss the epidemiology, immunology, and therapeutic approaches of different types of skin cancer.

Opportunistic Infections and Immune-Related Adverse Events Associated with Administering Immune Checkpoint Inhibitors: A Narrative Review

Manipulating the immune system by blocking the immune checkpoint receptors is the basis of immunotherapy, a relevant tool in current clinical oncology. The strategy of blocking the immune checkpoints (Immune Checkpoint Inhibitors, ICI) consists of using monoclonal antibodies to inhibit the interaction between ligand and inhibitory receptors from triggering a complete activation of helper and cytotoxic T cells to fight against tumour cells. Immunotherapy has benefited patients with diverse cancers such as stomach, lung, melanoma, and head and neck squamous cell carcinoma, among others. Unfortunately, a growing number of reports have indicated that the ICI treatment also can show a dark side under specific conditions; some of the adverse effects induced by ICI are immunosuppression, opportunistic infections, and organ-specific alterations. This review discusses some immunologic aspects related to these unwanted effects.

Cutaneous immune-related adverse events to immune checkpoint inhibitors: from underlying immunological mechanisms to multi-omics prediction

The development of immune checkpoint inhibitors (ICIs) has dramatically altered the landscape of therapy for multiple malignancies, including urothelial carcinoma, non-small cell lung cancer, melanoma and gastric cancer. As part of their anti-tumor properties, ICIs can enhance susceptibility to inflammatory side effects known as immune-related adverse events (irAEs), in which the skin is one of the most commonly and rapidly affected organs. Although numerous questions still remain unanswered, multi-omics technologies have shed light into immunological mechanisms, as well as the correlation between ICI-induced activation of immune systems and the incidence of cirAE (cutaneous irAEs). Therefore, we reviewed integrated biological layers of omics studies combined with clinical data for the prediction biomarkers of cirAEs based on skin pathogenesis. Here, we provide an overview of a spectrum of dermatological irAEs, discuss the pathogenesis of this "off-tumor toxicity" during ICI treatment, and summarize recently investigated biomarkers that may have predictive value for cirAEs via multi-omics approach. Finally, we demonstrate the prognostic significance of cirAEs for immune checkpoint blockades.

Immune-related adverse events of immune checkpoint inhibitors: a review

Since the first Immune Checkpoint Inhibitor was developed, tumor immunotherapy has entered a new era, and the response rate and survival rate of many cancers have also been improved. Despite the success of immune checkpoint inhibitors, resistance limits the number of patients who can achieve a lasting response, and immune-related adverse events complicate treatment. The mechanism of immune-related adverse events (irAEs) is unclear. We summarize and discuss the mechanisms of action of immune checkpoint inhibitors, the different types of immune-related adverse events and their possible mechanisms, and describe possible strategies and targets for prevention and therapeutic interventions to mitigate them.

Immune-related adverse events in checkpoint blockade: Observations from human tissue and therapeutic considerations

Checkpoint inhibitors (CPIs) are monoclonal antibodies which, by disrupting interactions of immune checkpoint molecules with their ligands, block regulatory immune signals otherwise exploited by cancers. Despite revolutionary clinical benefits, CPI use is associated with an array of immune-related adverse events (irAEs) that mirror spontaneous autoreactivity. Severe irAEs necessitate pausing or stopping of CPI therapy and use of corticosteroids and/or other immunomodulatory interventions. Despite increasingly widespread CPI use, irAE pathobiology remains poorly understood; its elucidation may point to targeted mitigation strategies and uncover predictive biomarkers for irAE onset in patients, whilst casting new light on mechanisms of spontaneous immune-mediated disease. This review focuses on common CPI-induced irAEs of the gut, skin and synovial joints, and how these compare to immune-mediated diseases such as ulcerative colitis, vitiligo and inflammatory arthritis. We review current understanding of the immunological changes reported following CPI therapy at the level of peripheral blood and tissue. Many studies highlight dysregulation of cytokines in irAE-affected tissue, particularly IFNγ and TNF. IrAE-affected tissues are also predominantly infiltrated by T-cells, with low B-cell infiltration. Whilst there is variability between studies, patients treated with anti-programmed cell death-1 (PD-1)/PDL-1 therapies seem to exhibit CD8+ T-cell dominance, with CD4+ T-cells dominating in those treated with anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) monotherapy. Interestingly, CD8+CXCR3+ T-cells have been reported to be elevated in gastrointestinal, dermatological and musculoskeletal -irAE affected tissues. These findings may highlight potential opportunities for therapeutic development or re-deployment of existing therapies to prevent and/or improve the outcome of irAEs.

Immunotherapy for Melanoma: The Significance of Immune Checkpoint Inhibitors for the Treatment of Advanced Melanoma

Therapeutic options for treating advanced melanoma have progressed rapidly in recent decades. Until 6 years ago, the regimen for treating advanced melanoma consisted mainly of cytotoxic agents such as dacarbazine and type I interferons. Since 2014, anti-programmed cell death 1 (PD1) antibodies have been recognized as anchor drugs for treating advanced melanoma, with or without additional combination drugs such as ipilimumab, but the efficacies of these immunotherapies are not fully satisfactory. In this review, we describe the development of the currently available anti-PD1 Abs-based immunotherapies for advanced melanoma, focusing on their efficacy and immune-related adverse events (AEs), as well as clinical trials still ongoing for the future treatment of advanced melanoma.

Molecular Docking and Intracellular Translocation of Extracellular Vesicles for Efficient Drug Delivery

Extracellular vesicles (EVs), including exosomes, mediate intercellular communication by delivering their contents, such as nucleic acids, proteins, and lipids, to distant target cells. EVs play a role in the progression of several diseases. In particular, programmed death-ligand 1 (PD-L1) levels in exosomes are associated with cancer progression. Furthermore, exosomes are being used for new drug-delivery systems by modifying their membrane peptides to promote their intracellular transduction via micropinocytosis. In this review, we aim to show that an efficient drug-delivery system and a useful therapeutic strategy can be established by controlling the molecular docking and intracellular translocation of exosomes. We summarise the mechanisms of molecular docking of exosomes, the biological effects of exosomes transmitted into target cells, and the current state of exosomes as drug delivery systems.

Loss of epidermal Langerhans cells in psoriasiform lesions of de novo induced or worsened pre-existing psoriasis following uses of immune checkpoint inhibitors

Immune checkpoint inhibitors (ICI), including monoclonal antibodies to programmed death 1, programmed death ligand 1, and cytotoxic T lymphocyte-associated antigen 4, have provided great therapeutic benefits for cancer patients at advanced stages. However, the introduction of ICI frequently results in the development of immune-related adverse events (irAE) through activation of autoreactive T cells. Here, we present three cases of cancer patients with cutaneous irAE, including development of de novo psoriasis and exacerbation of pre-existing psoriasis. Interestingly, these patients shared an altered histological feature characterized by loss of epidermal CD1a⁺ cells, namely Langerhans cells (LC), in the psoriasiform lesions in contrast to "conventional psoriasis" exhibiting unchanged or activated LC. A possible underlying mechanism was that ICI-mediated hyperactivation of effector T cells contributed to aggravation or establishment of psoriasis phenotype, which might be associated with direct cytotoxicity or expulsion of LC from the epidermis.