Dexamethasone enhances programmed cell death 1 (PD-1) expression during T cell activation: an insight into the optimum application of glucocorticoids in anti-cancer therapy

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

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

CAR T cells and T cells phenotype and function are impacted by glucocorticoid exposure with different magnitude

BACKGROUND

Chimeric antigen receptor (CAR) T cell therapy is associated with high risk of adverse events. Glucocorticoids (GCs) are cornerstone in the management of high-grade cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). Given the potentially deleterious effects of GCs on CAR T cells anti-tumor activity, increasing our understanding of GCs impact on CAR T cells is crucial.

METHODS

Using several CAR T cells i.e., CD19, mesothelin (MSLN)-CD28 and MSLN-41BB CAR T cells (M28z and MBBz), we compared phenotypical, functional, changes and anti-tumor activity between i) transduced CD19 CAR T cells with untransduced T cells, ii) M28z with MBBz CAR T cells induced by Dexamethasone (Dx) or Methylprednisolone (MP) exposures.

RESULTS

Higher levels of GC receptor were found in less differentiated CAR T cells. Overall, Dx and MP showed a similar impact on CAR T cells. Compared to untreated condition, GCs exposure increased the expression of PD-1 and TIM-3 and reduced the expression of LAG3 and function of T cells and CAR T cells. GC exposures induced more exhausted (LAG3 + PD1 + TIM3 +) and dysfunctional (CD107a-INFγ-TNF-IL2-) untransduced T cells in comparison to CD19 CAR T cells. GC exposure impaired more CD4 + than CD8 + CD19 CAR T cells. GC exposures increased more PD-1 expression associated with reduced proliferative capacity and function of M28z as compared to MBBz CAR T cells. CAR T cells anti-tumor activity was greatly affected by repeated GC exposure but partly recovered within 48h after GCs withdrawal.

CONCLUSIONS

In summary, GCs impacted phenotype and function of untransduced and CAR T cell with different magnitude. The nature of the CAR costimulatory domain influenced the magnitude of CAR T cell response to GCs.

Identification of C-PLAN index as a novel prognostic predictor for advanced lung cancer patients receiving immune checkpoint inhibitors

Objective

Increasing studies have highlighted the potential utility of non-invasive prognostic biomarkers in advanced lung cancer patients receiving immune checkpoint inhibitor (ICI) based anti-cancer therapies. Here, a novel prognostic predictor named as C-PLAN integrating C-reactive protein (CRP), Performance status (PS), Lactate dehydrogenase (LDH), Albumin (ALB), and derived Neutrophil-to-lymphocyte ratio (dNLR) was identified and validated in a single-center retrospective cohort.

Methods

The clinical data of 192 ICI-treated lung cancer patients was retrospectively analyzed. The pretreatment levels of CRP, PS, LDH, ALB and dNLR were scored respectively and then their scores were added up to form C-PLAN index. The correlation of C-PLAN index with the progression-free survival (PFS) or overall survival (OS) was analyzed by a Kaplan-Meier model. The multivariate analysis was used to identify whether C-PLAN index was an independent prognostic predictor.

Results

A total of 88 and 104 patients were included in the low and high C-PLAN index group respectively. High C-PLAN index was significantly correlated with worse PFS and OS in ICI-treated lung cancer patients (both p<0.001). The multivariate analysis revealed high C-PLAN index was an independent unfavorable factor affecting PFS (hazard ratio (HR)=1.821; 95%confidence interval (CI)=1.291-2.568) and OS (HR=2.058, 95%CI=1.431-2.959). The high C-PLAN index group had a significantly lower disease control rate than the low C-PLAN index group (p=0.024), while no significant difference was found for objective response rate (p=0.172). The subgroup analysis based on clinical features (pathological type, therapy strategy, TNM stage and age) confirmed the prognostic value of C-PLAN index, except for patients receiving ICI monotherapy or with age ranging from 18 to 65 years old. Finally, a nomogram was constructed based on C-PLAN index, age, gender, TNM stage and smoking status, which could predict well the 1-, 2- and 3-year survival of ICI-treated lung cancer patients.

Conclusion

The C-PLAN index has great potential to be utilized as a non-invasive, inexpensive and reliable prognostic predictor for advanced lung cancer patients receiving ICI-based anti-cancer therapies.

Mononuclear cell composition and activation in blood and mucosal tissue of eosinophilic esophagitis

Introduction

Eosinophilic esophagitis (EoE) is a chronic, inflammatory, antigen-driven disease of the esophagus. Tissue EoE pathology has previously been extensively characterized by novel transcriptomics and proteomic platforms, however the majority of surface marker determination and screening has been performed in blood due to mucosal tissue size limitations. While eosinophils, CD4+ T cells, mast cells and natural killer (NK) T cells were previously investigated in the context of EoE, an accurate picture of the composition of peripheral blood mononuclear cells (PBMC) and their activation is missing.

Methods

In this study, we aimed to comprehensively analyze the composition of peripheral blood mononuclear cells and their activation using surface marker measurements with multicolor flow cytometry simultaneously in both blood and mucosal tissue of patients with active EoE, inactive EoE, patients with gastroesophageal reflux disease (GERD) and controls. Moreover, we set out to validate our data in co-cultures of PBMC with human primary esophageal epithelial cells and in a novel inducible mouse model of eosinophilic esophagitis, characterized by extensive IL-33 secretion in the esophagus.

Results

Our results indicate that specific PBMC populations are enriched, and that they alter their surface expression of activation markers in mucosal tissue of active EoE. In particular, we observed upregulation of the immunomodulatory molecule CD38 on CD4+ T cells and on myeloid cells in biopsies of active EoE. Moreover, we observed significant upregulation of PD-1 on CD4+ and myeloid cells, which was even more prominent after corticosteroid treatment. With co-culture experiments we could demonstrate that direct cell contact is needed for PD-1 upregulation on CD4+ T cells. Finally, we validated our findings of PD-1 and CD38 upregulation in an inducible mouse model of EoE.

Discussion

Herein we show significant alterations in the PBMC activation profile of patients with active EoE in comparison to inactive EoE, GERD and controls, which could have potential implications for treatment. To our knowledge, this study is the first of its kind expanding the multi-color flow cytometry approach in different patient groups using in vitro and in vivo translational models.

NF-κB and STAT3 activation in CD4 T cells in pediatric MOG antibody-associated disease

In this study, we examined CD4 T cell activation using various stimuli in pediatric MOGAD patients (n = 4, untreated remission samples) and healthy controls (n = 5), to understand how both antigen-specific and bystander mechanisms contribute to CD4 T cell activation in MOGAD. TNFα, IL6, and MOG peptide pool were found to activate NF-κB or STAT3 pathways by measuring the expression of regulators (A20, IκBα) and phosphorylated subunits (phospho-p65 and phospho-STAT3) using immunolabeling. Prednisolone reversed activation of both NF-κB and STAT3 and increased the expression of A20 and IκBα. TNFR blocking partially reversed NF-κB activation in certain CD4 T cell subsets, but did not effect STAT3 activation. We observed that activation of NF-κB and STAT3 in response to various stimuli behaves mostly same in MOGAD (remission) and HC. IL6 stimulation resulted in higher STAT3 phosphorylation in MOGAD patients at 75 min, specifically in central and effector memory CD4 T cells (with unadjusted p-values). These findings suggest the potential therapeutic targeting of NF-κB and STAT3 pathways in MOGAD. Further investigation is needed to validate the significance of extended STAT3 phosphorylation and its correlation with IL6 receptor blocker treatment response.

Multiple suppressing small interfering RNA for cancer treatment-Application to triple-negative breast cancer

Certain cancers, such as triple-negative breast cancer (TNBC), pose a challenging prognosis due to the absence of identifiable hormone-related receptors and effective targeted therapies. Consequently, novel therapeutics are required for these cancers, offering minimal side effects and reduced drug resistance. Unexpectedly, siRNA-7, initially employed as a control, exhibited significant efficacy in inhibiting cell viability in MDA-MB-231 cells. Through a genome-wide search of seed sequences, the targets of siRNA-7 were identified as cancer-related genes, namely PRKCE, RBPJ, ZNF737, and CDC7 in MDA-MB-231 cells. The mRNA repression analysis confirmed the simultaneous suppression by siRNA-7. Combinatorial administration of single-targeting siRNAs demonstrated a comparable reduction in viability to that achieved by siRNA-7. Importantly, siRNA-7 selectively inhibited cell viability in MDA-MB-231 cells, while normal HDF-n cells remained unaffected. Furthermore, in a xenograft mouse model, siRNA-7 exhibited a remarkable 76% reduction in tumor volume without any loss in body weight. These findings position siRNA-7 as a promising candidate for a novel, safe, specific, and potent TNBC cancer therapeutic. Moreover, the strategy of multiple suppressing small interfering RNA holds potential for the treatment of various diseases associated with gene overexpression.

Toxicity evaluation of synthetic glucocorticoids against breast cancer cell lines MDA-MB-231, MCF-7 and human embryonic kidney HEK293

In this study, we conducted a comprehensive assessment of the cytotoxicity of three glucocorticoids, namely Hydrocortisone, Dexamethasone, and Methylprednisolone, using three different human cell lines: MDA-MB-231, MCF-7 (both adenocarcinoma cell lines), and HEK293 (kidney epithelial cell line). At lower concentrations exceeding 50 µM, we did not observe any significant toxic effects of these glucocorticoids. However, when exposed to higher concentrations, Hydrocortisone exhibited dose-dependent cytotoxic effects on all three cell lines, with calculated IC50 values of 12 ± 0.6 mM for HEK293, 2.11 ± 0.05 mM for MDA-MB-231, and 2.73 ± 0.128 mM for MCF-7 cells after 48 h of exposure. Notably, Hydrocortisone, at its respective IC50 concentrations, demonstrated an inhibitory effect on the proliferation of the cancer cell lines, as evidenced by a substantial reduction in BrdU absorbance in a dose-dependent manner, coupled with a markedly reduced rate of colony formation in treated cells. Furthermore, Hydrocortisone exhibited remarkable anti-migratory properties in MDA-MB-231 and MCF-7 cells, and it induced cell cycle arrest in the SubG1 phase in MDA-MB-231 cells. In addition to these effects, Hydrocortisone triggered apoptosis in both cancer cell types, leading to observable morphological changes. This apoptotic response was characterized by a significant increase in the activity of caspase-3, which was time-dependent. Additionally, Hydrocortisone downregulated the expression of anti-apoptotic Bcl-2 proteins. In summary, our findings underscore the safety of clinical doses in terms of cell toxicity meanwhile increased concentration were showing an anti-proliferative potential of Hydrocortisone, particularly against adenocarcinoma breast cancer cell lines.

Tumors produce glucocorticoids by metabolite recycling, not synthesis, and activate Tregs to promote growth

Glucocorticoids are steroid hormones with potent immunosuppressive properties. Their primary source is the adrenals, where they are generated via de novo synthesis from cholesterol. In addition, many tissues have a recycling pathway in which glucocorticoids are regenerated from inactive metabolites by the enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1, encoded by Hsd11b1). Here, we find that multiple tumor types express Hsd11b1 and produce active glucocorticoids. Genetic ablation of Hsd11b1 in such cells had no effect on in vitro growth, but reduced in vivo tumor progression, which corresponded with increased frequencies of CD8+ tumor-infiltrating lymphocytes (TILs) expressing activation markers and producing effector cytokines. Tumor-derived glucocorticoids were found to promote signatures of Treg activation and suppress signatures of conventional T cell activation in tumor-infiltrating Tregs. Indeed, CD8+ T cell activation was restored and tumor growth reduced in mice with Treg-specific glucocorticoid receptor deficiency. Importantly, pharmacologic inhibition of 11β-HSD1 reduced tumor growth to the same degree as gene knockout and rendered immunotherapy-resistant tumors susceptible to PD-1 blockade. Given that HSD11B1 expression is upregulated in many human tumors and that inhibition of 11β-HSD1 is well tolerated in clinical studies, these data suggest that targeting 11β-HSD1 may be a beneficial adjunct in cancer therapy.

Corticosteroids and Cancer Immunotherapy

Despite revolutionizing cancer management, immunotherapies dysregulate the immune system, leading to immune-mediated adverse events. These common and potentially dangerous toxicities are often treated with corticosteroids, which are among the most prescribed drugs in oncology for a wide range of cancer and noncancer indications. While steroids exert several mechanisms to reduce immune activity, immunotherapies, such as immune checkpoint inhibitors (ICI), are designed to enhance the immune system's inherent antitumor activity. Because ICI requires an intact and robust immune response, the immunosuppressive properties of steroids have led to a widespread concern that they may interfere with antitumor responses. However, the existing data of the effect of systemic steroids on immunotherapy efficacy remain somewhat conflicted and unclear. To inform clinical decision-making and improve outcomes, we review the impact of steroids on antitumor immunity, recent advances in the knowledge of their impact on ICI efficacy in unique populations and settings, associated precautions, and steroid-sparing treatment approaches.

Genetic control of the dynamic transcriptional response to immune stimuli and glucocorticoids at single-cell resolution

Synthetic glucocorticoids, such as dexamethasone, have been used as a treatment for many immune conditions, such as asthma and, more recently, severe COVID-19. Single-cell data can capture more fine-grained details on transcriptional variability and dynamics to gain a better understanding of the molecular underpinnings of inter-individual variation in drug response. Here, we used single-cell RNA-seq to study the dynamics of the transcriptional response to glucocorticoids in activated peripheral blood mononuclear cells from 96 African American children. We used novel statistical approaches to calculate a mean-independent measure of gene expression variability and a measure of transcriptional response pseudotime. Using these approaches, we showed that glucocorticoids reverse the effects of immune stimulation on both gene expression mean and variability. Our novel measure of gene expression response dynamics, based on the diagonal linear discriminant analysis, separated individual cells by response status on the basis of their transcriptional profiles and allowed us to identify different dynamic patterns of gene expression along the response pseudotime. We identified genetic variants regulating gene expression mean and variability, including treatment-specific effects, and showed widespread genetic regulation of the transcriptional dynamics of the gene expression response.

Immunosuppression for immune-related adverse events during checkpoint inhibition: an intricate balance

Immune checkpoint inhibitors (ICIs) have changed perspectives for patients with cancer, but come with severe immune-related adverse events (irAEs). To prevent fatality or chronicity, these irAEs are often promptly treated with high-dose immunosuppressants. Until recently, evidence on the effects of irAE management on ICI efficacy has been sparse. As a result, algorithms for irAE management are mostly expert-opinion based and barely consider possible detrimental effects of immunosuppressants on ICI efficacy. However, recent growing evidence suggests that vigorous immunosuppressive management of irAEs comes with unfavourable effects on ICI efficacy and survival. With expansion of the indications of ICIs, evidence-based treatment of irAEs without hampering tumour control becomes more and more important. In this review, we discuss novel evidence from pre-clinical and clinical studies on the effects of different irAE management regimens including corticosteroids, TNF inhibition and tocilizumab on cancer control and survival. We provide recommendations for pre-clinical research, cohort studies and clinical trials that can help clinicians in tailored irAE management, minimising patients' burden while maintaining ICI efficacy.

KGANSynergy: knowledge graph attention network for drug synergy prediction

Combination therapy is widely used to treat complex diseases, particularly in patients who respond poorly to monotherapy. For example, compared with the use of a single drug, drug combinations can reduce drug resistance and improve the efficacy of cancer treatment. Thus, it is vital for researchers and society to help develop effective combination therapies through clinical trials. However, high-throughput synergistic drug combination screening remains challenging and expensive in the large combinational space, where an array of compounds are used. To solve this problem, various computational approaches have been proposed to effectively identify drug combinations by utilizing drug-related biomedical information. In this study, considering the implications of various types of neighbor information of drug entities, we propose a novel end-to-end Knowledge Graph Attention Network to predict drug synergy (KGANSynergy), which utilizes neighbor information of known drugs/cell lines effectively. KGANSynergy uses knowledge graph (KG) hierarchical propagation to find multi-source neighbor nodes for drugs and cell lines. The knowledge graph attention network is designed to distinguish the importance of neighbors in a KG through a multi-attention mechanism and then aggregate the entity's neighbor node information to enrich the entity. Finally, the learned drug and cell line embeddings can be utilized to predict the synergy of drug combinations. Experiments demonstrated that our method outperformed several other competing methods, indicating that our method is effective in identifying drug combinations.

Glucocorticoid Receptor and Ovarian Cancer: From Biology to Therapeutic Intervention

Ovarian cancer (OC) is the leading cause of death from gynecological malignancies worldwide. Fortunately, recent advances in OC biology and the discovery of novel therapeutic targets have led to the development of novel therapeutic agents that may improve the outcome of OC patients. The glucocorticoid receptor (GR) is a ligand-dependent transcriptional factor known for its role in body stress reactions, energy homeostasis and immune regulation. Notably, evidence suggests that GR may play a relevant role in tumor progression and may affect treatment response. In cell culture models, administration of low levels of glucocorticoids (GCs) suppresses OC growth and metastasis. Conversely, high GR expression has been associated with poor prognostic features and long-term outcomes in patients with OC. Moreover, both preclinical and clinical data have shown that GR activation impairs the effectiveness of chemotherapy by inducing the apoptotic pathways and cell differentiation. In this narrative review, we summarize data related to the function and role of GR in OC. To this aim, we reorganized the controversial and fragmented data regarding GR activity in OC and herein describe its potential use as a prognostic and predictive biomarker. Moreover, we explored the interplay between GR and BRCA expression and reviewed the latest therapeutic strategies such as non-selective GR antagonists and selective GR modulators to enhance chemotherapy sensitivity, and to finally provide new treatment options in OC patients.

Reactivation of Anticancer Immunity by Resetting Interorgan Crosstalk in Immune-Suppressive Cells with a Nanoparticulated Anti-Inflammatory Drug

The reactivation of anticancer immunity is a fundamental principle in cancer immunotherapy as evidenced by the use of immune checkpoint inhibitors (ICIs). While treatment with the ICIs is shown to have remarkable and durable therapeutic effects in the responders, the low objective response rate (<40%) continues to be a major problem. Since myeloid-derived suppressor cells (MDSCs), heterogenous cells with strong immunosuppressive activity that originate in the hematopoietic system, suppress the anticancer immunity via parallel immune checkpoint-dependent and independent pathways, these cells are potential targets for improving the efficacy of cancer immunotherapy. In this study, it is demonstrated that MDSCs can be depleted by delivering synthetic glucocorticoid dexamethasone to phagocytic cells in the spleen using a lipid nanoparticle. Since the interaction of nanoparticles with T cells is intrinsically poor, this strategy also enables the "detargeting" from T cells, thus avoiding the nonspecific suppression of cytotoxic immune responses against cancer cells. In addition to the direct anticancer effect of the nanoparticulated dexamethasone, their synergistic anticancer effect with ICIs is also reported.

Impact of endogenous glucocorticoid on response to immune checkpoint blockade in patients with advanced cancer

Background

Previous studies indicate that exogenous use of glucocorticoid (GC) affects immune checkpoint inhibitor (ICI) efficacy. However, there is a paucity of clinical data evaluating the direct impact of endogenous GC on the efficacy for cancer patients with immune checkpoint blockade.

Methods

We first compared the endogenous circulating GC levels in healthy individuals and patients with cancer. We next retrospectively reviewed patients with advanced cancer with PD-1/PD-L1 inhibitor alone or combination therapy in a single center. The effects of baseline circulating GC levels on objective response rate (ORR), durable clinical benefit (DCB), progression-free survival (PFS), and overall survival (OS) were analyzed. The association of the endogenous GC levels with circulating lymphocytes, cytokines levels, and neutrophil to lymphocyte ratio, and tumor infiltrating immune cells, were systematically analyzed.

Results

The endogenous GC levels in advanced cancer patients were higher than those in early-stage cancer patients as well as healthy people. In the advanced cancer cohort with immune checkpoint blockade (n=130), patients with high baseline endogenous GC levels (n=80) had a significantly reduced ORR (10.0% vs 40.0%; p<0.0001) and DCB (35.0% vs 73.5%, p=0.001) compared to those with low endogenous GC levels (n=50). The increased GC levels was significantly associated with reduced PFS (HR 2.023; p=0.0008) and OS (HR 2.809; p=0.0005). Moreover, statistically significant differences regarding PFS, and OS were also detected after propensity score matching. In a multivariable model, the endogenous GC was identified as an independent indicator for predicting PFS (HR 1.779; p=0.012) and OS (HR 2.468; p=0.013). High endogenous GC levels were significantly associated with reduced lymphocytes (p=0.019), increased neutrophil to lymphocyte ratio (p=0.0009), and increased interleukin-6 levels (p=0.025). Patients with high levels of endogenous GC had low numbers of tumor infiltrating CD3⁺ (p=0.001), CD8⁺ T (p=0.059), and CD4⁺ T (p=0.002) cells, and the numbers of circulating PD-1⁺ NK cells (p=0.012), and the ratio of CD8⁺PD-1⁺ to CD4⁺PD-1⁺ (p=0.031) were higher in patients with high levels of endogenous GC compared to low levels of endogenous GC.

Conclusion

Baseline endogenous GC increase executes a comprehensive negative effect on immunosurveillance and response to immunotherapy in real-world cancer patients accompanied with cancer progression.

Ginsenoside Rg1 modulates intestinal microbiota and supports re-generation of immune cells in dexamethasone-treated mice

Ginsenoside Rg1 is one of the major ginsenosides found in roots of Panax ginseng and Panax notoginseng. Ginsenoside Rg1 is known to possess various biological activities including immunity enhancement activity. However, it is not clear whether the regulation of immune function by Rg1 is related to the intestinal microbiota. In the present study, the immuno-modulatory and gut microbiota-reshaping effects of ginsenoside Rg1 were evaluated. Ginsenoside Rg1 acts as an immune-enhancing agent to increase spleen index and the number of T, B and dendritic cells in dexamethasone (Dex)-treated mice. Ginsenoside Rg1 also increased the production of sIgA and regulated the expression of interleukin 2 (IL-2), IL-4, IL-10 and IFN-γ. Meanwhile, Rg1 administration regulated the structure of intestinal microbiota. The relative abundance of mouse intestinal microbial groups, such as Alistipes, Ruminococcaceae, Lachnospiraceae, and Roseburia were increased by Rg1 administration, whereas a decrease in the potential pathogens like Helicobacteraceae, Dubosiella, Mycoplasma, Alloprevotella, Allobaculum was observed. Moreover, Rg1 metabolites of Lachnospiraceae bacterium enhanced the proliferation of CD4+ T cells and T regulatory (Treg) cells. Ginsenoside Rg1 improved the inflammatory condition of the colonic tissue and repaired the destructed mucosal barrier. This study suggested that Rg1 strengthens immunity with regulating the homeostasis of intestinal microbiota in mice.

Acute effects of FLT3L treatment on T cells in intact mice

Peripheral T cells express a diverse repertoire of antigen-specific receptors, which together protect against the full range of pathogens. In this context, the total repertoire of memory T cells which are maintained by trophic signals, long after pathogen clearance, is critical. Since these trophic factors include cytokines and self-peptide-MHC, both of which are available from endogenous antigen-presenting cells (APC), we hypothesized that enhancing APC numbers in vivo can be a viable strategy to amplify the population of memory T cells. We evaluated this by acutely treating intact mice with FMS-like tyrosine kinase 3 ligand (Flt3l), which promotes expansion of APCs. Here we report that this treatment allowed for, an expansion of effector-memory CD4+ and CD8+ T cells as well as an increase in their expression of KLRG1 and CD25. In the lymph nodes and spleen, the expansion was limited to a specific CD8 (CD44-low but CD62L-) subset. Functionally, this subset is distinct from naïve T cells and could produce significant amounts of effector cytokines upon restimulation. Taken together, these data suggest that the administration of Flt3L can impact both APC turnover as well as a corresponding flux of specific subsets of CD8+ T cells in an intact peripheral immune compartment.

Effects of glucocorticoids on leukocytes: Genomic and non-genomic mechanisms

Glucocorticoids (GCs) have been widely used as immunosuppressants and anti-inflammatory agents to treat a variety of autoimmune and inflammatory diseases, and they fully exert their anti-inflammatory and immune-regulating effects in the body. The effect of GCs on white blood cells is an important part of their action. GCs can cause changes in peripheral blood white blood cell counts by regulating the proliferation, differentiation, and apoptosis of white blood cells. Although the total number of white blood cells, neutrophil counts, lymphocytes, and eosinophils increases, the counts of basic granulocytes and macrophages decreases. In addition, GCs can regulate the activation and secretion of white blood cells, inhibit the secretion of a variety of pro-inflammatory cytokines, the expression of chemokines, and promote the production of anti-inflammatory cytokines. For patients on GC therapy, the effects of GCs on leukocytes were similar to the changes in peripheral blood caused by bacterial infections. Thus, we suggest that clinicians should be more cautious in assessing the presence of infection in children with long-term use of GCs and avoid overuse of antibiotics in the presence of elevated leukocytes. GCs work through genomic and non-genomic mechanisms in the human body, which are mediated by GC receptors. In recent years, studies have not fully clarified the mechanism of GCs, and further research on these mechanisms will help to develop new therapeutic strategies.

Pharmacological Treatments Available for Immune-Checkpoint-Inhibitor-Induced Colitis

Immune checkpoint inhibitor treatment has shown revolutionary therapeutic effects in various carcinomas. However, immune-related adverse events (irAE) following this treatment can sometimes lead to treatment discontinuation. One such frequently encountered adverse event is immune-related colitis (irAE colitis). Corticosteroids (CS) are the first-line treatment for irAE colitis, but we often encounter CS-refractory or -resistant cases. The application of multiple biologics has been proposed as a therapy to be administered after CS treatment; however, the efficacy and safety of biologics for patients with irAE colitis who do not respond to CS have not been established. This review summarizes the treatment regimens available for irAE colitis, focusing on the mechanism of action of corticosteroids, infliximab, vedolizumab, and other drugs.

Is Timing of Steroid Exposure Prior to Immune Checkpoint Inhibitor Initiation Associated with Treatment Outcomes in Melanoma? A Population-Based Study

Immune checkpoint inhibitors (ICIs) harness the immune system and are the therapy of choice for multiple cancers. Although immunosuppressive agents such as steroids are also used in many cancers, it is unknown how their timing affects treatment outcomes. Thus, we investigated the relationship between the timing of steroid exposure preceding ICI administration and subsequent treatment outcomes in melanoma. This population-based study utilized the SEER-Medicare-linked database to identify patients diagnosed with melanoma between 1991 and 2015 and receiving ICIs between 2010 and 2016, examining last steroid exposure in the 12 months preceding ICI. The main outcome was all-cause mortality (ACM) after ICIs. Modifications of the Cox proportional hazards model were used to calculate time-dependent hazards. Of 1671 patients with melanoma receiving ICIs, 907 received steroids. Compared with no steroids, last steroid exposures ≤1 month and 1-3 months prior to ICIs were associated with a 126% and 51% higher ACM within 3 months post ICI initiation, respectively (hazard ratio (HR): 2.26, 95% CI: 1.65-3.08; and HR: 1.51, 95% CI: 1.01-2.27). Steroid exposure within 3 months of initiating ICIs was associated with increased mortality up to 6 months after ICI. Further investigation is warranted to elucidate mechanisms affecting outcomes due to steroids.

Impact of Glucocorticoid Use in Oncology in the Immunotherapy Era

Thanks to their anti-inflammatory, anti-oedema, and anti-allergy properties, glucocorticoids are among the most widely prescribed drugs in patients with cancer. The indications for glucocorticoid use are very wide and varied in the context of cancer and include the symptomatic management of cancer-related symptoms (compression, pain, oedema, altered general state) but also prevention or treatment of common side effects of anti-cancer therapies (nausea, allergies, etc.) or immune-related adverse events (irAE). In this review, we first give an overview of the different clinical situations where glucocorticoids are used in oncology. Next, we describe the current state of knowledge regarding the effects of these molecules on immune response, in particular anti-tumour response, and we summarize available data evaluating how these effects may interfere with the efficacy of immunotherapy using immune checkpoint inhibitors.

Advantages and drawbacks of dexamethasone in glioblastoma multiforme

The most widespread, malignant, and deadliest type of glial tumor is glioblastoma multiforme (GBM). Despite radiation, chemotherapy, and radical surgery, the median survival of afflicted individuals is about 12 months. Unfortunately, existing therapeutic interventions are abysmal. Dexamethasone (Dex), a synthetic glucocorticoid, has been used for many years to treat brain edema and inflammation caused by GBM. Several investigations have recently shown that Dex also exerts antitumoral effects against GBM. On the other hand, more recent disputed findings have questioned the long-held dogma of Dex treatment for GBM. Unfortunately, steroids are associated with various undesirable side effects, including severe immunosuppression and metabolic changes like hyperglycemia, which may impair the survival of GBM patients. Current ideas and concerns about Dex's effects on GBM cerebral edema, cell proliferation, migration, and its clinical outcomes were investigated in this study.

Immunotherapy after liver transplantation: Where are we now?

BACKGROUND

There is limited evidence on the safety of immunotherapy use after liver transplantation and its efficacy in treating post-liver transplant hepatocellular carcinoma (HCC) recurrence.

AIM

To assess the safety of immunotherapy after liver transplant and its efficacy in treating post-liver transplant HCC recurrence.

METHODS

A literature review was performed to identify patients with prior liver transplantation and subsequent immunotherapy. We reviewed the rejection rate and risk factors of rejection. In patients treated for HCC, the oncological outcomes were evaluated including objective response rate, progression-free survival (PFS), and overall survival (OS).

RESULTS

We identified 25 patients from 16 publications and 3 patients from our institutional database (total n = 28). The rejection rate was 32% (n = 9). Early mortality occurred in 21% (n = 6) and was mostly related to acute rejection (18%, n = 5). Patients who developed acute rejection were given immunotherapy earlier after transplantation (median 2.9 years vs 5.3 years, P = 0.02) and their graft biopsies might be more frequently programmed death ligand-1-positive (100% vs 33%, P = 0.053). Their PFS (1.0 ± 0.1 mo vs 3.5 ± 1.1 mo, P = 0.02) and OS (1.0 ± 0.1 mo vs 19.2 ± 5.5 mo, P = 0.001) compared inferiorly to patients without rejection. Among the 19 patients treated for HCC, the rejection rate was 32% (n = 6) and the overall objective response rate was 11%. The median PFS and OS were 2.5 ± 1.0 mo and 7.3 ± 2.7 mo after immunotherapy.

CONCLUSION

Rejection risk is the major obstacle to immunotherapy use in liver transplant recipients. Further studies on the potential risk factors of rejection are warranted.

Integrative computational immunogenomic profiling of cortisol-secreting adrenocortical carcinoma

Adrenocortical carcinoma (ACC) is a rare but highly aggressive malignancy. Nearly half of ACC tumours overproduce and secrete adrenal steroids. Excess cortisol secretion, in particular, has been associated with poor prognosis among ACC patients. Furthermore, recent immunotherapy clinical trials have demonstrated significant immunoresistance among cortisol‐secreting ACC (CS‐ACC) patients when compared to their non‐cortisol‐secreting (nonCS‐ACC) counterparts. The immunosuppressive role of excess glucocorticoid therapies and hypersecretion is known; however, the impact of the cortisol hypersecretion on ACC tumour microenvironment (TME), immune expression profiles and immune cell responses remain largely undefined. In this study, we characterized the TME of ACC patients and compared the immunogenomic profiles of nonCS‐ACC and CS‐ACC tumours to assess the impact of differentially expressed genes (DEGs) by utilizing The Cancer Genome Atlas (TCGA) database. Immunogenomic comparison (CS‐ vs. nonCS‐ACC tumour TMEs) demonstrated an immunosuppressive expression profile with a direct impact on patient survival. We identified several primary prognostic indicators and potential targets within ACC tumour immune landscape. Differentially expressed immune genes with prognostic significance provide additional insight into the understanding of potential contributory mechanisms underlying failure of initial immunotherapeutic trials and poor prognosis of patients with CS‐ACC.

Therapeutic potential and deleterious effect of glucocorticoids on azoxymethane/dextran sulfate sodium-induced colorectal cancer in mice

Glucocorticoids (GCs) are widely used in the treatment of various autoimmune and inflammatory diseases, including inflammatory bowel disease (IBD). However, the effect of GCs on the progression of colitis-associated colorectal cancer (CAC) has not been well explored. In this study, we first established a colorectal cancer model induced by azoxymethane and dextran sulfate sodium (AOM/DSS) and a colitis model induced by DSS in mice. Dexamethasone (DEX) was then administered at different periods of time to determine its effect on tumorigenesis and tumor progression. Meanwhile, body weight, stool property and fecal blood of mice were recorded. At the end of this study, the number and load of tumors were evaluated, and the expression of proteins associated with cell proliferation was analyzed. To evaluate the inflammation in colon, we detected the level of pro-inflammatory cytokine TNFα, and the mucosal infiltration of inflammatory cells. Our results revealed that AOM injection followed by three cycles of drinking water containing 1.5% DSS successfully induced multiple tumor formation in mouse colon and rectum. Both early and late DEX intervention suppressed tumor growth in mouse colorectum, and downregulated the expression of PCNA and cyclin D1. Moreover, DEX treatment significantly inhibited TNFα production, mucosal infiltration of inflammatory cells, and the activity of MAPK/JNK pathway, particularly early DEX intervention. However, we also found that DEX treatment deteriorated the general state of mouse manifested by greater loss of body weight and rectal bleeding. In summary, both early and late DEX interventions significantly ameliorate colonic inflammation and inhibit the progression of AOM/DSS-induced colorectal cancer, at least partly due to the inhibition of MAPK/JNK pathway. It is noteworthy that the deleterious effect on the general condition of mouse may limit the duration of GCs treatment.

Genetic control of the dynamic transcriptional response to immune stimuli and glucocorticoids at single cell resolution.. [PMID: 35313584 PMCID: PMC8936121 DOI: 10.1101/2021.09.30.462672] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Synthetic glucocorticoids, such as dexamethasone, have been used as treatment for many immune conditions, such as asthma and more recently severe COVID-19. Single cell data can capture more fine-grained details on transcriptional variability and dynamics to gain a better understanding of the molecular underpinnings of inter-individual variation in drug response. Here, we used single cell RNA-seq to study the dynamics of the transcriptional response to glucocorticoids in activated Peripheral Blood Mononuclear Cells from 96 African American children. We employed novel statistical approaches to calculate a mean-independent measure of gene expression variability and a measure of transcriptional response pseudotime. Using these approaches, we demonstrated that glucocorticoids reverse the effects of immune stimulation on both gene expression mean and variability. Our novel measure of gene expression response dynamics, based on the diagonal linear discriminant analysis, separated individual cells by response status on the basis of their transcriptional profiles and allowed us to identify different dynamic patterns of gene expression along the response pseudotime. We identified genetic variants regulating gene expression mean and variability, including treatment-specific effects, and demonstrated widespread genetic regulation of the transcriptional dynamics of the gene expression response.

Association of Systemic Steroid Treatment and Outcome in Patients Treated with Immune Checkpoint Inhibitors: A Real-World Analysis

Background: Immune-related adverse events (irAEs) are inflammatory side effects, which can occur during immune-checkpoint(s) inhibitors (ICIs) therapy. Steroids are the first-line agents to manage irAEs because of their immunosuppressive properties. However, it is still debated whether or when steroids can be administered without abrogating the therapeutic efforts of immunotherapy. Methods: We retrospectively evaluated 146 patients with metastatic non-small cell lung cancer (NSCLC), melanoma and renal cell carcinoma (RCC) treated with ICIs. We assessed the progression-free survival (PFS) of patients treated with steroids due to an irAE compared to a no-steroid group. Results: The early treatment with steroid (within the first 30 days from the beginning of immunotherapy) was not related to a shorter PFS (p = 0.077). Interestingly, patients who were treated with steroids after 30 days from the start of immunotherapy had significantly longer PFS (p = 0.017). In a multivariate analysis, treatment with steroids after 30 days was an independent prognostic factor for PFS (HR: 0.59 [95% CI 0.36–0.97], p = 0.037). Conclusions: This retrospective study points out that early systemic steroids administration to manage irAEs might not have a detrimental effect on patient clinical outcome in NSCLC, melanoma and RCC patients.

Glucocorticoid and PD-1 Cross-Talk: Does the Immune System Become Confused?

Programmed cell death protein 1 (PD-1) and its ligands, PD-L1/2, control T cell activation and tolerance. While PD-1 expression is induced upon T cell receptor (TCR) activation or cytokine signaling, PD-L1 is expressed on B cells, antigen presenting cells, and on non-immune tissues, including cancer cells. Importantly, PD-L1 binding inhibits T cell activation. Therefore, the modulation of PD-1/PD-L1 expression on immune cells, both circulating or in a tumor microenvironment and/or on the tumor cell surface, is one mechanism of cancer immune evasion. Therapies that target PD-1/PD-L1, blocking the T cell-cancer cell interaction, have been successful in patients with various types of cancer. Glucocorticoids (GCs) are often administered to manage the side effects of chemo- or immuno-therapy, exerting a wide range of immunosuppressive and anti-inflammatory effects. However, GCs may also have tumor-promoting effects, interfering with therapy. In this review, we examine GC signaling and how it intersects with PD-1/PD-L1 pathways, including a discussion on the potential for GC- and PD-1/PD-L1-targeted therapies to "confuse" the immune system, leading to a cancer cell advantage that counteracts anti-cancer immunotherapy. Therefore, combination therapies should be utilized with an awareness of the potential for opposing effects on the immune system.

Uncovering the interplay between pH receptors and immune cells: Potential drug targets (Review)

Extracellular acidosis is associated with various immunopathological states. The microenvironment of numerous solid tumours and inflammatory responses during acute or chronic infection are all related to a pH range of 5.5‑7.0. The relationship between inflammation and immune escape, cancer metabolism, and immunologic suppression drives researchers to focus on the effects of low pH on diverse components of disease immune monitoring. The potential effect of low extracellular pH on the immune function reveals the importance of pH in inflammatory and immunoreactive processes. In this review, the mechanism of how pH receptors, including monocarboxylate transporters (MCTs), Na⁺/H⁺ exchanger 1, carbonic anhydrases (CAs), vacuolar‑ATPase, and proton‑sensing G‑protein coupled receptors (GPCRs), modulate the immune system in disease, especially in cancer, were studied. Their role in immunocyte growth and signal transduction as part of the immune response, as well as cytokine production, have been documented in great detail. Currently, immunotherapy strategies have positive therapeutic effects for patients. However, the acidic microenvironment may block the effect of immunotherapy through compensatory feedback mechanisms, leading to drug resistance. Therefore, we highlight promising therapeutic developments regarding pH manipulation and provide a framework for future research.

Corticosteroid administration for cancer-related indications is an unfavorable prognostic factor in solid cancer patients receiving immune checkpoint inhibitor treatment

OBJECTIVE

Immunotherapies targeting immune checkpoints have achieved encouraging survival benefits in patients with various solid cancers. Corticosteroids are frequently administrated for cancer/non-cancer related indications and immune-related adverse events (irAEs). This study aimed to clarify the prognostic significance of corticosteroid administration in solid cancer patients receiving immune checkpoint inhibitor (ICI) treatment.

METHOD

First, a meta-analysis was performed using the literatures searched from PubMed, Cochrane Library, Web of Science, Embase, and Clinicaltrials.gov before January 2021. The Hazard ratios (HRs) coupled with 95% confidence intervals (CIs) were used to evaluate the correlation of corticosteroid administration with overall survival (OS) and progression-free survival (PFS). Then, a retrospective analysis enrolling 118 ICI-treated cancer patients was performed for validation, among which 26 patients received corticosteroids for cancer-related indications.

RESULT

In the meta-analysis, corticosteroid administration for cancer-related indications was significantly correlated with worse PFS (HR = 1.735(1.381-2.180)) and OS (HR = 1.936(1.587-2.361)) of the ICI-treated patients. However, corticosteroid administration for non-cancer-related indications and irAEs was unrelated with PFS (non-cancer-related indications: HR = 0.830(0.645-1.067); irAEs: HR = 1.302(0.628-2.696)) and OS (non-cancer-related indications: HR = 0.786(0.512-1.206); irAEs: HR = 1.107(0.832-1.474)) of the ICI-treated patients. The following retrospective analysis identified corticosteroid administration for cancer-related indications was an independent unfavorable predictor for PFS (P = 0.006) and OS (P = 0.044) of the ICI-treated patients. The subgroup analysis based on non-small cell lung cancer (NSCLC) demonstrated the similar results (P = 0.002 for PFS and P = 0.047 for OS).

CONCLUSION

Our study demonstrated corticosteroid administration for cancer-related indications is an unfavorable prognostic factor in solid cancer patients receiving ICI treatment. Therefore, careful selection of corticosteroid-treated patients for ICI therapy is quite necessary in individualized clinical management.

Activated, Pro-Inflammatory Th1, Th17, and Memory CD4+ T Cells and B Cells Are Involved in Delayed-Type Hypersensitivity Arthritis (DTHA) Inflammation and Paw Swelling in Mice

Delayed-type hypersensitivity arthritis (DTHA) is a recently established experimental model of rheumatoid arthritis (RA) in mice with pharmacological values. Despite an indispensable role of CD4+ T cells in inducing DTHA, a potential role for CD4+ T cell subsets is lacking. Here we have quantified CD4+ subsets during DTHA development and found that levels of activated, pro-inflammatory Th1, Th17, and memory CD4+ T cells in draining lymph nodes were increased with differential dynamic patterns after DTHA induction. Moreover, according to B-cell depletion experiments, it has been suggested that this cell type is not involved in DTHA. We show that DTHA is associated with increased levels of B cells in draining lymph nodes accompanied by increased levels of circulating IgG. Finally, using the anti-rheumatoid agents, methotrexate (MTX) and the anti-inflammatory drug dexamethasone (DEX), we show that MTX and DEX differentially suppressed DTHA-induced paw swelling and inflammation. The effects of MTX and DEX coincided with differential regulation of levels of Th1, Th17, and memory T cells as well as B cells. Our results implicate Th1, Th17, and memory T cells, together with activated B cells, to be involved and required for DTHA-induced paw swelling and inflammation.

PD-1/PD-L1 Axis as a Potential Therapeutic Target for Multiple Sclerosis: A T Cell Perspective

The programmed cell death protein-1/programmed death ligand-1 (PD-1/PD-L1) axis is a widely studied immune checkpoint that modulates signaling pathways related to T cell activation. The use of PD-1/PD-L1 inhibitors is a promising immune therapy strategy for cancer patients. However, individuals treated with PD-1/PD-L1 inhibitors may develop immune-related adverse events due to excessive immune reactions. Multiple sclerosis (MS) is a chronic demyelinating and neurodegenerative disease of the central nervous system. T cells and the PD-1/PD-L1 axis play vital roles in the pathogenesis of MS. A better understanding of the complex relationship between the PD-1/PD-L1 axis and T cells may extend our knowledge of the molecular mechanisms and therapeutic approaches for MS. In this review, we summarize the most recent findings regarding the role of the PD-1/PD-L1 axis in MS and discuss the potential therapeutic strategies to modulate the expression of PD-1/PD-L1 in MS.

Timing of steroid initiation and response rates to immune checkpoint inhibitors in metastatic cancer

Background

Corticosteroids (CS) are the mainstay of immune-related adverse effect (irAE) management, as well as for other indications in cancer treatment. Previous studies evaluating whether CS affect immune checkpoint inhibitor (CPI) efficacy compared patients receiving CS versus no CS. However, there is a paucity of clinical data evaluating the timing of concomitant CS and CPI efficacy.

Methods

We retrospectively collected data from patients who received CS during CPI treatment at a single institution. Patients were in two cohorts based on timing of initiation of CS (≥2 months vs <2 months after initiating CPI). Patient characteristics, irAEs, cancer type, treatment type, treatment response/progression per RECIST V.1.1, and survival data were collected. Kaplan-Meier and Cox proportional hazard regression methods estimated HRs for the primary endpoint of progression-free survival (PFS) along with overall survival (OS).

Results

We identified 247 patients with metastatic cancer who received CS concurrently with CPIs. The median time on CS was 1.8 months. After adjusting for treatment type, tumor type, brain metastases, and irAEs, those treated with CS ≥2 months after starting CPI had a statistically significant longer PFS (HR=0.30, p<0.001), and OS (HR 0.34, p<0.0001) than those who received CS <2 months after starting CPI. Objective response rate (ORR) for patients on CS ≥2 months was 39.8%, versus ORR for patients <2 months was 14.7% (p value =<0.001)

Conclusion

Our results suggest that early use of CS during CPI treatment significantly hinders CPI efficacy. This data needs to be validated prospectively. Future studies should focus on the immune mechanisms by which CSs affect T-cell function early in the CPI treatment course.

Impact of corticosteroid use on outcomes of non-small-cell lung cancer patients treated with immune checkpoint inhibitors: A systematic review and meta-analysis

WHAT IS KNOWN AND OBJECTIVE

Administration of corticosteroids to immune checkpoint inhibitors (ICI)-treated patients has raised concerns due to doubts about ICIs' efficacy under those conditions. Hence, we reviewed studies comparing overall and progression-free survival (OS and PFS) outcomes in patients with non-small-cell lung carcinoma (NSCLC) treated with ICI and either with or without corticosteroids for any reason.

METHODS

We searched the PubMed Central, Cochrane library, EMBASE and MEDLINE databases from inception until February 2021 for relevant publications. We used the Newcastle-Ottawa scale to assess the quality of the identified studies. We used the published data to carry out a meta-analysis with a random-effects model and report pooled odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

We included data from 14 studies with 5461 participants in the meta-analysis. Most studies were retrospective in nature and of low quality, and most of them were conducted in the USA and in European countries. Nivolumab is the most common ICI used in the included studies followed by pembrolizumab. We found that patients using corticosteroids had reduced OSs (pooled HR, 1.82; 95% CI, 1.51-2.18) and PFSs (pooled HR, 1.69; 95% CI, 1.41-2.04) than the patients not using corticosteroids. We identified significant heterogeneity and publication bias for both the outcomes. However, the sensitivity analysis revealed that the estimates were robust to the individual study effects.

WHAT IS NEW AND CONCLUSION

Our findings suggest that corticosteroids significantly reduce the OS and PFS of patients with NSCLC under ICI therapy. Hence, clinicians and oncologists should consider this information when prescribing corticosteroids for this target population.

PD-1/PD-L1 in Cancer: Pathophysiological, Diagnostic and Therapeutic Aspects

Immune evasion is a key strategy adopted by tumor cells to escape the immune system while promoting their survival and metastatic spreading. Indeed, several mechanisms have been developed by tumors to inhibit immune responses. PD-1 is a cell surface inhibitory receptor, which plays a major physiological role in the maintenance of peripheral tolerance. In pathological conditions, activation of the PD-1/PD-Ls signaling pathway may block immune cell activation, a mechanism exploited by tumor cells to evade the antitumor immune control. Targeting the PD-1/PD-L1 axis has represented a major breakthrough in cancer treatment. Indeed, the success of PD-1 blockade immunotherapies represents an unprecedented success in the treatment of different cancer types. To improve the therapeutic efficacy, a deeper understanding of the mechanisms regulating PD-1 expression and signaling in the tumor context is required. We provide an overview of the current knowledge of PD-1 expression on both tumor-infiltrating T and NK cells, summarizing the recent evidence on the stimuli regulating its expression. We also highlight perspectives and limitations of the role of PD-L1 expression as a predictive marker, discuss well-established and novel potential approaches to improve patient selection and clinical outcome and summarize current indications for anti-PD1/PD-L1 immunotherapy.

Endogenous Glucocorticoid Signaling Regulates CD8+ T Cell Differentiation and Development of Dysfunction in the Tumor Microenvironment

Identifying signals in the tumor microenvironment (TME) that shape CD8⁺ T cell phenotype can inform novel therapeutic approaches for cancer. Here, we identified a gradient of increasing glucocorticoid receptor (GR) expression and signaling from naïve to dysfunctional CD8⁺ tumor-infiltrating lymphocytes (TILs). Conditional deletion of the GR in CD8⁺ TILs improved effector differentiation, reduced expression of the transcription factor TCF-1, and inhibited the dysfunctional phenotype, culminating in tumor growth inhibition. GR signaling transactivated the expression of multiple checkpoint receptors and promoted the induction of dysfunction-associated genes upon T cell activation. In the TME, monocyte-macrophage lineage cells produced glucocorticoids and genetic ablation of steroidogenesis in these cells as well as localized pharmacologic inhibition of glucocorticoid biosynthesis improved tumor growth control. Active glucocorticoid signaling associated with failure to respond to checkpoint blockade in both preclinical models and melanoma patients. Thus, endogenous steroid hormone signaling in CD8⁺ TILs promotes dysfunction, with important implications for cancer immunotherapy.

Not Sweet: Glucocorticoids from Intratumoral Myeloid Cells Disable T Cells

In this issue, Acharya et al. demonstrate that glucocorticoids produced by macrophages and monocytes in the tumor microenvironment induce a dysfunctional CD8⁺ T cell phenotype. Blocking myeloid glucocorticogenesis enhances tumor immune surveillance and responsiveness to immune checkpoint therapy.

Impact of the combined timing of PD-1/PD-L1 inhibitors and chemotherapy on the outcomes in patients with refractory lung cancer

Background

PD-1/PD-L1 inhibitors in combination with chemotherapy are widely used in clinical practice. However, the ideal combined timing of them has not been fully explored.

Methods

In this study, simulation experiments to explore the impacts of the combination of anti-PD-1 antibody (anti-PD-1 Ab) on the cytotoxic effects of chemotherapeutic drugs in peripheral blood mononuclear cells were performed. In addition, the effects of the combined timing of PD-1/PD-L1 inhibitors and chemotherapy on efficacy and safety were retrospectively analysed in patients with refractory lung cancer.

Results

Experiments in vitro showed that administering the anti-PD-1 Ab 3 days after chemotherapy (represented by dicycloplatin) resulted in significantly weaker cytotoxic effects on lymphocytes, compared with administering the anti-PD-1 Ab before or concurrent with chemotherapy. Moreover, data from 64 lung cancer patients treated with PD-1/PD-L1 inhibitors plus chemotherapy as a second- or higher-line therapy were retrospectively analysed. The results showed that administering PD-1/PD-L1 inhibitors 1-10 days (especially 3-5 days) after chemotherapy was associated with longer overall survival [17.3 months versus 12.7 months; hazard ratio (HR) = 0.58, 95% confidence interval (CI) 0.28-1.19, P = 0.137 in univariate analysis; HR = 0.36, 95% CI 0.16-0.80, P = 0.012 in multivariate analysis] and a trend of improved progression-free survival (5.1 months versus 4.2 months; HR = 0.81, 95% CI 0.42-1.54, P = 0.512) compared with administering PD-1/PD-L1 inhibitors before or concurrent with chemotherapy.

Conclusion

Our findings suggest that administering PD-1/PD-L1 inhibitors 1-10 days (especially 3-5 days) after chemotherapy is superior to administering PD-1/PD-L1 inhibitors before or concurrent with chemotherapy in patients with refractory lung cancer, but this result needs to be further explored by prospective studies.

•

The cytotoxic effects of chemotherapeutic drugs were positively correlated with the activation states of PBMCs.

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Administering the anti-PD-1 Ab 3 days after chemotherapy resulted in weaker cytotoxic effects on lymphocytes in vitro.

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Administering PD-1/PD-L1 inhibitors a few days after chemotherapy resulted in better survival in lung cancer patients.

Interplay between glucocorticoids and tumor-infiltrating lymphocytes on the prognosis of adrenocortical carcinoma

Background

Adrenocortical carcinoma (ACC) is a rare endocrine malignancy. Tumor-related glucocorticoid excess is present in ~60% of patients and associated with particularly poor prognosis. Results of first clinical trials using immune checkpoint inhibitors were heterogeneous. Here we characterize tumor-infiltrating T lymphocytes (TILs) in ACC in association with glucocorticoids as potential explanation for resistance to immunotherapy.

Methods

We performed immunofluorescence analysis to visualize tumor-infiltrating T cells (CD3⁺), T helper cells (CD3⁺CD4⁺), cytotoxic T cells (CD3⁺CD8⁺) and regulatory T cells (Tregs; CD3⁺CD4⁺FoxP3⁺) in 146 ACC tissue specimens (107 primary tumors, 16 local recurrences, 23 metastases). Quantitative data of immune cell infiltration were correlated with clinical data (including glucocorticoid excess).

Results

86.3% of ACC specimens showed tumor infiltrating T cells (7.7 cells/high power field (HPF)), including T helper (74.0%, 6.7 cells/HPF), cytotoxic T cells (84.3%, 5.7 cells/HPF) and Tregs (49.3%, 0.8 cells/HPF). The number of TILs was associated with better overall survival (HR for death: 0.47, 95% CI 0.25 to 0.87), which was true for CD4⁺− and CD8⁺ subpopulations as well. In localized, non-metastatic ACC, the favorable impact of TILs on overall and recurrence-free survival was manifested even independently of ENSAT (European Network for the Study of Adrenal Tumors) stage, resection status and Ki67 index. T helper cells were negatively correlated with glucocorticoid excess (Phi=−0.290, p=0.009). Patients with glucocorticoid excess and low TILs had a particularly poor overall survival (27 vs. 121 months in patients with TILs without glucocorticoid excess).

Conclusion

Glucocorticoid excess is associated with T cell depletion and unfavorable prognosis. To reactivate the immune system in ACC by checkpoint inhibitors, an inhibition of adrenal steroidogenesis might be pivotal and should be tested in prospective studies.

Expression Profiling of Primary and Recurrent Glioblastomas Reveals a Reduced Level of Pentraxin 3 in Recurrent Glioblastomas

Glioblastomas (GBM) are highly infiltrative tumors and despite intensive treatment tumor recurrence is inevitable. The immune microenvironment in recurrent GBM is poorly characterized, but it is potentially influenced by therapeutic interventions with surgery, radiotherapy, and chemotherapy. The aim of this study was to obtain a deeper insight in the immune microenvironment in primary and recurrent GBM. Primary and recurrent glioblastoma samples from 18 patients were identified and expression profiling of 770 myeloid innate immune-related markers was performed. Leukemia inhibitory factor and pentraxin 3 were expressed at lower levels in recurrent tumors. Using in silico data and immunohistochemical staining, this was validated for pentraxin 3. Both high leukemia inhibitory factor and pentraxin 3 expression appeared to be associated with shorter survival in primary and recurrent GBM using in silico data. In primary GBM, gene set analysis also showed higher expression of genes involved in metabolism, extracellular matrix remodeling and complement activation, whereas genes involved in T cell activation and checkpoint signaling were expressed at higher levels in recurrent GBM. The reduced level of pentraxin 3 in recurrent glioblastomas and the gene set analysis results suggest an altered microenvironment in recurrent GBM that might be more active.

The Immune Checkpoint PD-1 in Natural Killer Cells: Expression, Function and Targeting in Tumour Immunotherapy

In the last years, immunotherapy with antibodies against programmed cell death protein 1 (PD-1) and programmed death-ligand 1 (PD-L1) has shown remarkable efficacy in the treatment of different types of tumours, representing a true revolution in oncology. While its efficacy has initially been attributed only to unleashing T cell responses, responsivity to PD-1/PD-L1 blockade was observed in some tumours with low Human Leukocyte Antigen (HLA) I expression and increasing evidence has revealed PD-1 surface expression and inhibitory function also in natural killer (NK) cells. Thus, the contribution of anti-PD-1/PD-L1 therapy to the recovery of NK cell anti-tumour response has recently been appreciated. Here, we summarize the studies investigating PD-1 expression and function in NK cells, together with the limitations and perspectives of immunotherapies. A better understanding of checkpoint biology is needed to design next-generation therapeutic strategies and to improve the clinical protocols of current therapies.

Pharmacodynamic mechanisms of anti-inflammatory drugs on the chemosensitization of multidrug-resistant cancers and the pharmacogenetics effectiveness

Drug resistance as a remarkable issue in cancer treatment is associated with inflammation which occurs through complex chemical reactions in the tumor microenvironment. Recent studies have implicated that glucocorticoids and NSAIDs are mainly useful combinations for inflammatory response modulation in chemotherapeutic protocols for cancer treatment. Immunosuppressive actions of glucocorticoids and NSAIDs are mainly mediated by the transrepression or activation regulation of inflammatory genes with different DNA-bound transcription factors including AP-1, NFAT, NF-κB, STAT and also, varying functions of COX enzymes in cancer cells. Interestingly, many investigations have proved the benefits of these anti-inflammatory agents in the quenching of multidrug resistance pathways. Numerous analyses on the ABC transporter promoters showed conserved nucleotide sequences with several DNA response elements that participate in transcriptional regulation. Furthermore, genetic variations in nucleotide sequences of membrane transporters were strongly associated with changes in these transporters' expression or function and a substantial impact on systemic drug exposure and toxicity. It appeared that several polymorphisms in MDR transporter genes especially MDR1 have influenced the regulatory mechanisms and explained differences in glucocorticoid responses.

New insights into the cell- and tissue-specificity of glucocorticoid actions

Glucocorticoids (GCs) are endogenous hormones that are crucial for the homeostasis of the organism and adaptation to the external environment. Because of their anti-inflammatory effects, synthetic GCs are also extensively used in clinical practice. However, almost all cells in the body are sensitive to GC regulation. As a result, these mediators have pleiotropic effects, which may be undesirable or detrimental to human health. Here, we summarize the recent findings that contribute to deciphering the molecular mechanisms downstream of glucocorticoid receptor activation. We also discuss the complex role of GCs in infectious diseases such as sepsis and COVID-19, in which the balance between pathogen elimination and protection against excessive inflammation and immunopathology needs to be tightly regulated. An understanding of the cell type- and context-specific actions of GCs from the molecular to the organismal level would help to optimize their therapeutic use.

Advances on immune-related adverse events associated with immune checkpoint inhibitors

Immunotherapy has recently led to a paradigm shift in cancer therapy, in which immune checkpoint inhibitors (ICIs) are the most successful agents approved for multiple advanced malignancies. However, given the nature of the non-specific activation of effector T cells, ICIs are remarkably associated with a substantial risk of immune-related adverse events (irAEs) in almost all organs or systems. Up to 90% of patients who received ICIs combination therapy experienced irAEs, of which majority were low-grade toxicity. Cytotoxic lymphocyte antigen-4 and programmed cell death protein-1/programmed cell death ligand 1 inhibitors usually display distinct features of irAEs. In this review, the mechanisms of action of ICIs and how they may cause irAEs are described. Some unsolved challenges, however really engrossing issues, such as the association between irAEs and cancer treatment response, tumor response to irAEs therapy, and ICIs in challenging populations, are comprehensively summarized.

Glucocorticoids rapidly inhibit cell migration through a novel, non-transcriptional HDAC6 pathway

Glucocorticoids (GCs) act through the glucocorticoid receptor (GR, also known as NR3C1) to regulate immunity, energy metabolism and tissue repair. Upon ligand binding, activated GR mediates cellular effects by regulating gene expression, but some GR effects can occur rapidly without new transcription. Here, we show that GCs rapidly inhibit cell migration, in response to both GR agonist and antagonist ligand binding. The inhibitory effect on migration is prevented by GR knockdown with siRNA, confirming GR specificity, but not by actinomycin D treatment, suggesting a non-transcriptional mechanism. We identified a rapid onset increase in microtubule polymerisation following GC treatment, identifying cytoskeletal stabilisation as the likely mechanism of action. HDAC6 overexpression, but not knockdown of αTAT1, rescued the GC effect, implicating HDAC6 as the GR effector. Consistent with this hypothesis, ligand-dependent cytoplasmic interaction between GR and HDAC6 was demonstrated by quantitative imaging. Taken together, we propose that activated GR inhibits HDAC6 function, and thereby increases the stability of the microtubule network to reduce cell motility. We therefore report a novel, non-transcriptional mechanism whereby GCs impair cell motility through inhibition of HDAC6 and rapid reorganization of the cell architecture.This article has an associated First Person interview with the first author of the paper.

Glucocorticoids and the cytokines IL-12, IL-15, and IL-18 present in the tumor microenvironment induce PD-1 expression on human natural killer cells

BACKGROUND

Programmed cell death protein 1 (PD-1)-immune checkpoint blockade has provided significant clinical efficacy across various types of cancer by unleashing both T and natural killer (NK) cell-mediated antitumor responses. However, resistance to immunotherapy occurs for many patients, rendering the identification of the mechanisms that control PD-1 expression extremely important to increase the response to the therapy.

OBJECTIVE

We sought to identify the stimuli and the molecular mechanisms that induce the de novo PD-1 expression on human NK cells in the tumor setting.

METHODS

NK cells freshly isolated from peripheral blood of healthy donors were stimulated with different combinations of molecules, and PD-1 expression was studied at the mRNA and protein levels. Moreover, ex vivo analysis of tumor microenvironment and NK cell phenotype was performed.

RESULTS

Glucocorticoids are indispensable for PD-1 induction on human NK cells, in cooperation with a combination of cytokines that are abundant at the tumor site. Mechanistically, glucocorticoids together with IL-12, IL-15, and IL-18 not only upregulate PDCD1 transcription, but also activate a previously unrecognized transcriptional program leading to enhanced mRNA translation and resulting in an increased PD-1 amount in NK cells.

CONCLUSIONS

These results provide evidence of a novel immune suppressive mechanism of glucocorticoids involving the transcriptional and translational control of an important immune checkpoint.