Regulatory B cell repertoire defects predispose lung cancer patients to immune-related toxicity following checkpoint blockade

Proteomic and metabolomic profiling of plasma predicts immune-related adverse events in older patients with advanced non-small cell lung cancer

The clinical success of immune checkpoint inhibitors is compromised by the fact of immune-related adverse events (irAEs), especially for older patients. To identify predictive biomarkers for older patients with irAEs, we used multiplex immunoassay and flow cytometry and liquid chromatography-tandem mass spectrometry to test immune factors and plasma protein and metabolites levels in non-small cell lung cancer (NSCLC) patients. The results showed that older patients with irAEs displayed lower CD28, CD4+ T cell, and B cell and higher interleukin (IL)-10 and CCL2 levels at baseline. Besides, lower aldolase, fructose-bisphosphate B (ALDOB), higher ST6GAL1, and lower lactate/pyruvate ratio at baseline were found in older patients with irAEs. Based on metabolomic markers, predictive models were developed to distinguish patients with grade 2-4 irAEs from grade 0-1 (Area under curve, AUC = 0.831) and to distinguish patients with grade 3-4 irAEs from grade 2 (AUC = 1). Our results confirmed the predictive value of plasma metabolites for irAEs in older patients with NSCLC.

Immune-related adverse events associated with first-line immune checkpoint inhibitors for metastatic renal cell carcinoma: A systematic review and network meta-analysis

BACKGROUND

In the realm of metastatic renal cell carcinoma (mRCC), the introduction of immune checkpoint inhibitors (ICIs) has revolutionized treatment paradigms. Despite their effectiveness, the comprehensive safety profile of these therapies remains inadequately explored. This network meta-analysis aims to comparing the safety profiles of ICI-based treatments in mRCC, offering vital insights that could lead to the optimization of treatment strategies and improvement of patient care.

METHODS

We conducted a comprehensive search of PubMed, Cochrane Library, Embase, Web of Science, ClinicalTrials.gov, Google Schola, OpenGrey and Scopus through November 1, 2023. The risk of bias assessment was performed using the Risk of Bias version 2 tool.

RESULTS

Seven randomized controlled trials (RCTs) with a total of 5976 patients were included for data analysis. The risk of bias results showed that all RCTs were considered "some concerns". The probability of hypothyroidism (surface under the cumulative ranking curve (SUCRA) = 0.981), hyperthyroidism (SUCRA = 0.983) and dermatologic immune-related adverse events (irAEs) (SUCRA = 0.955) in the Nivolumab + Cabozantinib ranked the first. The Avelumab + Axitinib had the highest incidence of adrenal insufficiency (AI) (SUCRA = 0.976), hepatitis (SUCRA = 0.937) and colitis (SUCRA = 0.864). The Nivolumab + Ipilimumab exhibited the highest incidence of pneumonitis (SUCRA = 0.755). Pembrolizumab + Lenvatinib had the highest incidence of nephritic irAEs (SUCRA = 0.788). The ICI-based group showed a higher incidence of hypothyroidism, hyperthyroidism, dermatologic irAEs, hepatitis and nephritic irAEs than sunitinib. However, the confidence in the evidence regarding the impact of ICI-based treatments on AI, pneumonia, and colitis remains limited.

CONCLUSION

The analysis focused on the probability of irAEs occurrence in each system when mRCC patients were treated with different ICI-based therapies, potentially offering significant value for guiding clinical prevention, early diagnosis, and management of irAEs. The limitations of the study included the potential heterogeneity and low certainty of part of the evidence.

B cells and the coordination of immune checkpoint inhibitor response in patients with solid tumors

Immunotherapy profoundly changed the landscape of cancer therapy by providing long-lasting responses in subsets of patients and is now the standard of care in several solid tumor types. However, immunotherapy activity beyond conventional immune checkpoint inhibition is plateauing, and biomarkers are overall lacking to guide treatment selection. Most studies have focused on T cell engagement and response, but there is a growing evidence that B cells may be key players in the establishment of an organized immune response, notably through tertiary lymphoid structures. Mechanisms of B cell response include antibody-dependent cellular cytotoxicity and phagocytosis, promotion of CD4+ and CD8+ T cell activation, maintenance of antitumor immune memory. In several solid tumor types, higher levels of B cells, specific B cell subpopulations, or the presence of tertiary lymphoid structures have been associated with improved outcomes on immune checkpoint inhibitors. The fate of B cell subpopulations may be widely influenced by the cytokine milieu, with versatile roles for B-specific cytokines B cell activating factor and B cell attracting chemokine-1/CXCL13, and a master regulatory role for IL-10. Roles of B cell-specific immune checkpoints such as TIM-1 are emerging and could represent potential therapeutic targets. Overall, the expanding field of B cells in solid tumors of holds promise for the improvement of current immunotherapy strategies and patient selection.

Investigating the impact of regulatory B cells and regulatory B cell-related genes on bladder cancer progression and immunotherapeutic sensitivity

BACKGROUND

Regulatory B cells (Bregs), a specialized subset of B cells that modulate immune responses and maintain immune tolerance in malignant tumors, have not been extensively investigated in the context of bladder cancer (BLCA). This study aims to elucidate the roles of Bregs and Breg-related genes in BLCA.

METHODS

We assessed Breg infiltration levels in 34 pairs of BLCA and corresponding paracancerous tissues using immunohistochemical staining. We conducted transwell and wound healing assays to evaluate the impact of Bregs on the malignant phenotype of SW780 and T24 cells. Breg-related genes were identified through gene sets and transcriptional analysis. The TCGA-BLCA cohort served as the training set, while the IMvigor210 and 5 GEO cohorts were used as external validation sets. We employed LASSO regression and random forest for feature selection and developed a risk signature using Cox regression. Primary validation of the risk signature was performed through immunohistochemical staining and RT-qPCR experiments using the 34 local BLCA samples. Additionally, we employed transfection assays and flow cytometry to investigate Breg expansion ability and immunosuppressive functions.

RESULTS

Breg levels in BLCA tissues were significantly elevated compared to paracancerous tissues (P < 0.05) and positively correlated with tumor malignancy (P < 0.05). Co-incubation of SW780 and T24 cells with Bregs resulted in enhanced invasion and migration abilities (all P < 0.05). We identified 27 Breg-related genes, including CD96, OAS1, and CSH1, which were integrated into the risk signature. This signature demonstrated robust prognostic classification across the 6 cohorts (pooled HR = 2.25, 95% CI = 1.52-3.33). Moreover, the signature exhibited positive associations with advanced tumor stage (P < 0.001) and Breg infiltration ratios (P < 0.05) in the local samples. Furthermore, the signature successfully predicted immunotherapeutic sensitivity in three cohorts (all P < 0.05). Knockdown of CSH1 in B cells increased Breg phenotype and enhanced suppressive ability against CD8 + T cells (all P < 0.05).

CONCLUSIONS

Bregs play a pro-tumor role in the development of BLCA. The Breg-related gene signature established in this study holds great potential as a valuable tool for evaluating prognosis and predicting immunotherapeutic response in BLCA patients.

Clinical and translational attributes of immune-related adverse events

With immune checkpoint inhibitors (ICIs) becoming the mainstay of treatment for many cancers, managing their immune-related adverse events (irAEs) has become an important part of oncological care. This Review covers the clinical presentation of irAEs and crucial aspects of reversibility, fatality and long-term sequelae, with special attention to irAEs in specific patient populations, such as those with autoimmune diseases. In addition, the genetic basis of irAEs, along with cellular and humoral responses to ICI therapy, are discussed. Detrimental effects of empirically used high-dose steroids and second-line immunosuppression, including impaired ICI effectiveness, call for more tailored irAE-treatment strategies. We discuss open therapeutic challenges and propose potential avenues to accelerate personalized management strategies and optimize outcomes.

Unraveling the complex interplay between anti-tumor immune response and autoimmunity mediated by B cells and autoantibodies in the era of anti-checkpoint monoclonal antibody therapies

The intricate relationship between anti-tumor immunity and autoimmunity is a complex yet crucial aspect of cancer biology. Tumor microenvironment often exhibits autoimmune features, a phenomenon that involves natural autoimmunity and the induction of humoral responses against self-antigens during tumorigenesis. This induction is facilitated by the orchestration of anti-tumor immunity, particularly within organized structures like tertiary lymphoid structures (TLS). Paradoxically, a significant number of cancer patients do not manifest autoimmune features during the course of their illness, with rare instances of paraneoplastic syndromes. This discrepancy can be attributed to various immune-mediated locks, including regulatory or suppressive immune cells, anergic autoreactive lymphocytes, or induction of effector cells exhaustion due to chronic stimulation. Overcoming these locks holds the risk to induce autoimmune mechanisms during cancer progression, a phenomenon notably observed with anti-immune checkpoint therapies, in contrast to more conventional treatments like chemotherapy or radiotherapy. Therefore, the challenge arises in managing immune-related adverse events (irAEs) induced by immune checkpoint inhibitors treatment, as decoupling them from the anti-tumor activity poses a significant clinical dilemma. This review summarizes recent advances in understanding the link between B-cell driven anti-tumor responses and autoimmune reactions in cancer patients, and discusses the clinical implications of this relationship.

Current progress, strategy, and prospects of PD-1/PDL-1 immune checkpoint biosensing platforms for cancer diagnostics, therapy monitoring, and drug screening

Recent technological advancements in testing and monitoring instrumentation have greatly contributed to the progress in cancer treatment by surgical, chemotherapeutic and radiotherapeutic interventions. However, the mortality rate still remains high, calling for the development of new treatment strategies with higher efficacy. Extensive efforts driven in this direction have included broadening of early cancer screening and applying innovative theranostic nanotechnologies. They have been supported by platforms introduced to enable the detection and monitoring of cancer biomarkers, inhibitors, and other agents, able to slow down cancer progression and prevent metastasis. Despite of the well-recognized principles of the immune checkpoint blockade, the efficacy of immunotherapy achieved so far does not meet the well-founded expectations. For a successful cancer treatment, highly sensitive, robust, and inexpensive multiplex biosensors have to be designed to aid in the biomarkers monitoring and in the development of new inhibitors. In this review, we provide an overview of the efforts undertaken to aid in the development and monitoring of anticancer immunotherapy, based on the programmed cell-death immune checkpoint (PD-1/PDL-1) blockade, by designing biosensors for the detection of relevant cancer biomarkers and their inhibitors screening. This review also emphasizes alternative targets made by exosomes carrying PD-L1 overexpressed in cancer cells and passed into the excreted exosomes. Evaluated are also novel targeted drug delivery nanocarriers, providing simultaneous biosensing, thereby contributing to the emerging immune checkpoint cancer therapy. On the basis of the current trends and the emerging technologies, future perspectives of cancer diagnostics and treatment monitoring using biosensing platforms are projected.

Considerations and Approaches for Cancer Immunotherapy in the Aging Host

Advances in cancer immunotherapy are improving treatment successes in many distinct cancer types. Nonetheless, most tumors fail to respond. Age is the biggest risk for most cancers, and the median population age is rising worldwide. Advancing age is associated with manifold alterations in immune cell types, abundance, and functions, rather than simple declines in these metrics, the consequences of which remain incompletely defined. Our understanding of the effects of host age on immunotherapy mechanisms, efficacy, and adverse events remains incomplete. A deeper understanding of age effects in all these areas is required. Most cancer immunotherapy preclinical studies examine young subjects and fail to assess age contributions, a remarkable deficit given the known importance of age effects on immune cells and factors mediating cancer immune surveillance and immunotherapy efficacy. Notably, some cancer immunotherapies are more effective in aged versus young hosts, while others fail despite efficacy in the young. Here, we review our current understanding of age effects on immunity and associated nonimmune cells, the tumor microenvironment, cancer immunotherapy, and related adverse effects. We highlight important knowledge gaps and suggest areas for deeper enquiries, including in cancer immune surveillance, treatment response, adverse event outcomes, and their mitigation.

Autoimmune PaneLs as PrEdictors of Toxicity in Patients TReated with Immune Checkpoint InhibiTors (ALERT)

BACKGROUND

Immune-checkpoint inhibitors (ICI) can lead to immune-related adverse events (irAEs) in a significant proportion of patients. The mechanisms underlying irAEs development are mostly unknown and might involve multiple immune effectors, such as T cells, B cells and autoantibodies (AutoAb).

METHODS

We used custom autoantigen (AutoAg) microarrays to profile AutoAb related to irAEs in patients receiving ICI. Plasma was collected before and after ICI from cancer patients participating in two clinical trials (NCT03686202, NCT02644369). A one-time collection was obtained from healthy controls for comparison. Custom arrays with 162 autoAg were used to detect IgG and IgM reactivities. Differences of median fluorescent intensity (MFI) were analyzed with Wilcoxon sign rank test and Kruskal-Wallis test. MFI 500 was used as threshold to define autoAb reactivity.

RESULTS

A total of 114 patients and 14 healthy controls were included in this study. irAEs of grade (G) ≥ 2 occurred in 37/114 patients (32%). We observed a greater number of IgG and IgM reactivities in pre-ICI collections from patients versus healthy controls (62 vs 32 p < 0.001). Patients experiencing irAEs G ≥ 2 demonstrated pre-ICI IgG reactivity to a greater number of AutoAg than patients who did not develop irAEs (39 vs 33 p = 0.040). We observed post-treatment increase of IgM reactivities in subjects experiencing irAEs G ≥ 2 (29 vs 35, p = 0.021) and a decrease of IgG levels after steroids (38 vs 28, p = 0.009).

CONCLUSIONS

Overall, these results support the potential role of autoAb in irAEs etiology and evolution. A prospective study is ongoing to validate our findings (NCT04107311).

Role of B cells in immune-related adverse events following checkpoint blockade

Blockade of immune checkpoints has transformed the therapy of several cancers. However, immune-related adverse events (irAEs) have emerged as a major challenge limiting the clinical application of this approach. B cells are recognized as major players in the pathogenesis of human autoimmunity and have been successfully targeted to treat these disorders. While T cells have been extensively studied as therapeutic targets of immune checkpoint blockade (ICB), these checkpoints also impact B cell tolerance. Blockade of immune checkpoints in the clinic is associated with distinct changes in the B cell compartment that correlate with the development of irAEs. In this review, we focus on the possible role of humoral immunity, specifically human B cell subsets and autoantibodies in the pathogenesis of ICB-induced irAEs. There remains an unmet need to better understand the T:B cell cross talk underlying the activation of pathogenic B cells and the development of ICB-induced irAEs. Such studies may identify new targets or approaches to prevent or treat irAEs and improve the application of ICB therapy in cancer.

Computational Methods for Single-Cell Proteomics

Advances in single-cell proteomics technologies have resulted in high-dimensional datasets comprising millions of cells that are capable of answering key questions about biology and disease. The advent of these technologies has prompted the development of computational tools to process and visualize the complex data. In this review, we outline the steps of single-cell and spatial proteomics analysis pipelines. In addition to describing available methods, we highlight benchmarking studies that have identified advantages and pitfalls of the currently available computational toolkits. As these technologies continue to advance, robust analysis tools should be developed in tandem to take full advantage of the potential biological insights provided by these data.

Immune-related adverse effects of checkpoint immunotherapy and implications for the treatment of patients with cancer and autoimmune diseases

During the past decade, there has been a revolution in cancer therapeutics by the emergence of antibody-based immunotherapies that modulate immune responses against tumors. These therapies have offered treatment options to patients who are no longer responding to classic anti-cancer therapies. By blocking inhibitory signals mediated by surface receptors that are naturally upregulated during activation of antigen-presenting cells (APC) and T cells, predominantly PD-1 and its ligand PD-L1, as well as CTLA-4, such blocking agents have revolutionized cancer treatment. However, breaking these inhibitory signals cannot be selectively targeted to the tumor microenvironment (TME). Since the physiologic role of these inhibitory receptors, known as immune checkpoints (IC) is to maintain peripheral tolerance by preventing the activation of autoreactive immune cells, IC inhibitors (ICI) induce multiple types of immune-related adverse effects (irAEs). These irAEs, together with the natural properties of ICs as gatekeepers of self-tolerance, have precluded the use of ICI in patients with pre-existing autoimmune diseases (ADs). However, currently accumulating data indicates that ICI might be safely administered to such patients. In this review, we discuss mechanisms of well established and newly recognized irAEs and evolving knowledge from the application of ICI therapies in patients with cancer and pre-existing ADs.

Predictors of immune checkpoint inhibitor-related adverse events in older patients with lung cancer: a prospective real-world analysis

PURPOSE

Older patients with cancer are underrepresented in pivotal trials of immune checkpoint inhibitors (ICIs). This study aimed to investigate immune-related adverse events (irAEs) that occur in older patients with lung cancer treated with ICIs, and explore predictors of the occurrence of irAEs.

METHODS

A prospective analysis was performed on older patients with lung cancer aged ≥ 65 years who were treated with anti-programmed cell death-1/-ligand 1 (PD-1/PD-L1) inhibitors in Beijing Hospital from January 2018 to December 2022. The incidence and risk factors of irAEs were estimated by the Chi-square test or Wilcoxon rank-sum tests. The predictive power of Geriatric-8 (G-8) for irAEs was tested by receiver operating characteristic (ROC) curve analysis. Lymphocyte counts were measured by flow cytometry. Cytokine levels were tested by Enzyme-linked immunosorbent assay, respectively. Kaplan-Meier method was used to calculated progression-free survival (PFS) curves, and the log-rank test was used to evaluate differences.

RESULTS

A total of 201 older patients aged ≥ 65 years with lung cancer were enrolled in this study. The most common irAEs were interstitial pneumonia, dermatological toxicity and hypothyroidism, with rates of 17.2%, 16.1% and 5.6%, respectively. ROC showed that G-8 could predict the occurrence of irAEs in patients aged 65-71 years (≥ G2 irAEs: AUC = 0.757, p < 0.001; ≥ G3 irAEs: AUC = 0.862, p < 0.001), but not for patients aged ≥ 71 years. NLR, LMR, PNI, hypertension and diabetes were associated with irAEs. Lower CD4 + T cells and B cells, and lower levels of IL-10 were associated with the development of irAEs.

CONCLUSION

Our study confirmed the accuracy of G-8 for predicting irAEs in older patients. We also identified several predictors of irAEs in older patients with lung cancer.

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.

Checkpoint inhibitor immune-related adverse events: A focused review on autoantibodies and B cells as biomarkers, advancements and future possibilities

The use of immune checkpoint inhibitors (ICIs) has evolved rapidly with unprecedented treatment benefits being obtained for cancer patients, including improved patient survival. However, over half of the patients experience immune related adverse events (irAEs) or toxicities, which can be fatal, affect the quality of life of patients and potentially cause treatment interruption or cessation. Complications from these toxicities can also cause long term irreversible organ damage and other chronic health conditions. Toxicities can occur in various organ systems, with common observations in the skin, rheumatologic, gastrointestinal, hepatic, endocrine system and the lungs. These are not only challenging to manage but also difficult to detect during the early stages of treatment. Currently, no biomarker exists to predict which patients are likely to develop toxicities from ICI therapy and efforts to identify robust biomarkers are ongoing. B cells and antibodies against autologous antigens (autoantibodies) have shown promise and are emerging as markers to predict the development of irAEs in cancer patients. In this review, we discuss the interplay between ICIs and toxicities in cancer patients, insights into the underlying mechanisms of irAEs, and the involvement of the humoral immune response, particularly by B cells and autoantibodies in irAE development. We also provide an appraisal of the progress, key empirical results and advances in B cell and autoantibody research as biomarkers for predicting irAEs. We conclude the review by outlining the challenges and steps required for their potential clinical application in the future.

Immune biology of NSCLC revealed by single-cell technologies: implications for the development of biomarkers in patients treated with immunotherapy

First-line immunotherapy in non-small-cell lung cancer largely improved patients' survival. PD-L1 testing is required before immune checkpoint inhibitor initiation. However, this biomarker fails to accurately predict patients' response. On the other hand, immunotherapy exposes patients to immune-related toxicity, the mechanisms of which are still unclear. Hence, there is an unmet need to develop clinically approved predictive biomarkers to better select patients who will benefit the most from immune checkpoint inhibitors and improve risk management. Single-cell technologies provide unprecedented insight into the tumor and its microenvironment, leading to the discovery of immune cells involved in immune checkpoint inhibitor response or toxicity. In this review, we will underscore the potential of the single-cell approach to identify candidate biomarkers improving non-small-cell lung cancer patients' care.

Germline genetic variation and predicting immune checkpoint inhibitor induced toxicity

Immune checkpoint inhibitor (ICI) therapy has revolutionised the treatment of various cancer types. ICIs reinstate T-cell function to elicit an anti-cancer immune response. The resulting immune response can however have off-target effects which manifest as autoimmune type serious immune-related adverse events (irAE) in ~10-55% of patients treated. It is currently challenging to predict both who will experience irAEs and to what severity. Identification of patients at high risk of serious irAE would revolutionise patient care. While the pathogenesis driving irAE development is still unclear, host genetic factors are proposed to be key determinants of these events. This review presents current evidence supporting the role of the host genome in determining risk of irAE. We summarise the spectrum and timing of irAEs following treatment with ICIs and describe currently reported germline genetic variation associated with expression of immuno-modulatory factors within the cancer immunity cycle, development of autoimmune disease and irAE occurrence. We propose that germline genetic determinants of host immune function and autoimmune diseases could also explain risk of irAE development. We also endorse genome-wide association studies of patients being treated with ICIs to identify genetic variants that can be used in polygenic risk scores to predict risk of irAE.

INFLECT: an R-package for cytometry cluster evaluation using marker modality

Background

Current methods of high-dimensional unsupervised clustering of mass cytometry data lack means to monitor and evaluate clustering results. Whether unsupervised clustering is correct is typically evaluated by agreement with dimensionality reduction techniques or based on benchmarking with manually classified cells. The ambiguity and lack of reproducibility of sequential gating has been replaced with ambiguity in interpretation of clustering results. On the other hand, spurious overclustering of data leads to loss of statistical power. We have developed INFLECT, an R-package designed to give insight in clustering results and provide an optimal number of clusters. In our approach, a mass cytometry dataset is overclustered intentionally to ensure the smallest phenotypically different subsets are captured using FlowSOM. A range of metacluster number endpoints are generated and evaluated using marker interquartile range and distribution unimodality checks. The fraction of marker distributions that pass these checks is taken as a measure of clustering success. The fraction of unimodal distributions within metaclusters is plotted against the number of generated metaclusters and reaches a plateau of diminishing returns. The inflection point at which this occurs gives an optimal point of capturing cellular heterogeneity versus statistical power.

Results

We applied INFLECT to four publically available mass cytometry datasets of different size and number of markers. The unimodality score consistently reached a plateau, with an inflection point dependent on dataset size and number of dimensions. We tested both ConsenusClusterPlus metaclustering and hierarchical clustering. While hierarchical clustering is less computationally expensive and thus faster, it achieved similar results to ConsensusClusterPlus. The four datasets consisted of labeled data and we compared INFLECT metaclustering to published results. INFLECT identified a higher optimal number of metaclusters for all datasets. We illustrated the underlying heterogeneity within labels, showing that these labels encompass distinct types of cells.

Conclusion

INFLECT addresses a knowledge gap in high-dimensional cytometry analysis, namely assessing clustering results. This is done through monitoring marker distributions for interquartile range and unimodality across a range of metacluster numbers. The inflection point is the optimal trade-off between cellular heterogeneity and statistical power, applied in this work for FlowSOM clustering on mass cytometry datasets.

Immune-checkpoint inhibitor use in patients with cancer and pre-existing autoimmune diseases

Immune-checkpoint inhibitors (ICIs) have dramatically changed the management of advanced cancers. Designed to enhance the antitumour immune response, they can also cause off-target immune-related adverse events (irAEs), which are sometimes severe. Although the efficacy of ICIs suggests that they could have wide-ranging benefits, clinical trials of the drugs have so far excluded patients with pre-existing autoimmune disease. However, evidence is accumulating with regard to the use of ICIs in this 'at-risk' population, with retrospective data suggesting that they have an acceptable safety profile, but that there is a risk of disease flare or other irAE occurrence. The management of immunosuppressive drugs at ICI initiation in patients with autoimmune disease (or later in instances of disease flare or irAE) remains a question of particular interest in clinical practice, in which there is always a search for the balance between protecting against autoimmunity and ensuring a good tumour response. Although temporary use of immunosuppressants seems safe, prolonged use or use at ICI initiation might hamper the antitumour immune response, prompting clinicians to use the minimal efficient immunosuppressive regimen. However, a new paradigm is emerging, in which inhibitors of TNF or IL-6 could have synergistic effects with ICIs on tumour response, while also preventing severe irAEs. If confirmed, this 'decoupling' effect on toxicity and efficacy could change therapeutic practice in this field. Knowledge of the current use of ICIs in patients with pre-existing autoimmune disease, particularly with regard to the use of immunosuppressive drugs and/or biologic DMARDs, can help to guide clinical practice.