Immune checkpoint inhibitor-related thyroid dysfunction

Immune checkpoint inhibitors and endocrinopathies in pediatric brain tumor patients

OBJECTIVES

Immune checkpoint inhibitors (ICIs) are emerging treatment options for children with brain tumors, who are already at risk for developing endocrinopathies due to tumor location and treatment. Endocrine ICI-related adverse effects (irAEs) are common in adults but poorly characterized in the pediatric population. The aims of this study were to determine in pediatric brain tumor patients in a single institution (1) if endocrine surveillance took place before and after ICIs were initiated, and (2) the occurrence of endocrine irAEs.

METHODS

This is a retrospective chart review of 22 pediatric brain tumor patients treated with ICIs at Children's Hospital Los Angeles between 2010 and 2022. We analyzed endocrine laboratory results, patient demographics, and treatment course.

RESULTS

Most patients (82 %) received surveillance in at least one endocrine system before ICI treatment - all had thyroid function tested (100 %) whereas non-thyroid endocrine functions were seldomly assessed (6-22 %). Only those patients with surveillance prior to treatment had ongoing surveillance after ICI initiation - 100 % for thyroid function and 17-39 % for other endocrine systems. Hypothyroidism was the only endocrine problem diagnosed after ICI initiation, in two patients (9 %). Of note, most patients (68 %) expired during or shortly after ICI treatment.

CONCLUSIONS

This is one of the first institutional surveys of pediatric ICIs in a high-volume pediatric brain tumor center. Thyroid surveillance commonly occurred in pediatric patients, revealing diagnoses of hypothyroidism, which is consistent with adult data. However, little information is available for non-thyroid endocrine conditions, reflecting the need for comprehensive and systematic endocrine surveillance.

Management, biomarkers and prognosis in people developing endocrinopathies associated with immune checkpoint inhibitors

Immune-related adverse events (irAEs), including endocrine irAEs, can occur in response to cancer immunotherapy using immune checkpoint inhibitors (ICIs). Of the endocrine irAEs, pituitary and thyroid irAEs are most frequently observed, followed by primary adrenal insufficiency, type 1 diabetes mellitus and hypoparathyroidism. Notably, pituitary irAEs and type 1 diabetes mellitus can be lethal if overlooked, potentially leading to adrenal crisis and diabetic ketoacidosis, respectively. On the other hand, pituitary and thyroid irAEs are reported to be associated with more favourable prognoses in some cancers if treated appropriately with hormone-replacement therapies. It would be useful to identify those people who are likely to develop endocrine irAEs before initiating therapy with ICIs. Anti-pituitary antibodies and thyroid autoantibodies have been identified as potential biomarkers for the development of pituitary and thyroid irAEs, respectively. This Review elaborates on the clinical characteristics and management strategies of several endocrine irAEs, using the latest research findings and guidelines published by several academic societies.

Clinical outcomes of endocrine and other disorders induced by immune checkpoint inhibitors in Japanese patients

The purpose of this study was to analyze the efficacy of treatment and survival after administration of immune checkpoint inhibitor (ICI) in Japanese patients and had endocrine-related and/or other immune-related adverse events (irAEs), as well as irAEs in multiple organs. This is a single-center, retrospective, observational study of 571 Japanese patients treated with ICI at our hospital. We evaluated the occurrence of Grade 3 or higher irAEs and the life expectancy and treatment efficacy after ICI administration. Endocrine-related irAE (E-irAE), other irAE (O-irAE), endocrine-related and other irAE (EO-irAE), and multiple endocrine-related irAE (ME-irAE) were evaluated in groups. 80.8% of patients had an irAE, with the highest incidence of irAE with ipilimumab plus PD-1 inhibitor, followed by atezolizumab 59.0%, pembrolizumab 53.7%, avelumab 50.0%, and nivolumab 47.3%, Durvamumab 26.7% followed; Kaplan-Meier survival curves showed higher survival rates in patients with irAE compared to non-irAE, and higher survival rates in EO-irAE and ME-irAE compared to E-irAE and O-irAE (p < 0.001). The COX proportional hazard ratios for overall survival were E-irAE 0.611 (0.480-0.772), O-irAE 0.758 (0.597-0.957), EO-irAE 0.622 (0.466-0.819) and ME-irAE 0.463 when non-irAE was set at 1.000 (0.257-0.775). When grade 3 or higher irAEs appeared, regardless of their type, there was a trend toward higher survival and post-treatment remission rates after ICI administration. In addition to this, patients with irAEs in multiple endocrine tissues and patients with irAEs in both endocrine and other organs had a better response to treatment after ICI administration.

Frequency and consequences of immune checkpoint inhibitor-associated inflammatory changes in different organs: an autopsy study over 13-years

While immune checkpoint inhibitors (ICIs) have revolutionized modern oncology, they are also associated with immune-related adverse events (irAEs). Previous histopathological descriptions of organ-related inflammatory changes do not consider systemic effects of ICIs, because of an absence of comprehensive autopsy studies. We performed a retrospective study on 42 whole-body autopsies of patients treated with ICIs from January 2011 to March 2024 to determine frequency, organ distribution and morphology of ICIs-associated inflammatory changes as well as their clinical relevance. Twenty-three of 42 patients (54.8%) presented irAEs with inflammatory changes in at least one organ. Most frequent irAEs were ICIs-related hypophysitis (N=12, 28.6%), myocarditis (N=8, 19.0%), pneumonitis (N=5, 11.9%), hepatitis (N=6, 14.3%), and adrenalitis (N=5, 11.9%). ICIs-related inflammation was mainly characterized by lympho-histiocytic and macrophage-rich tissue infiltrates, whereas a granulomatous "sarcoid-like" reaction was observed in one patient. Cause of death was attributable to ICIs-therapy in 7 patients (16.7%), with ICIs-associated myocarditis as the most common cause of death (N=5, 71.4%). Clinically, irAEs were unsuspected in 5 of 7 ICIs-related deaths (71.4%). Among irAEs, myocarditis has been clinically undiagnosed in 5 out of 8 cases (62.5%). Encephalitis was identified only at autopsy in all cases (N=2). Hypophysitis was clinically unsuspected in 8 of 12 cases (66.7%). Patients who died from irAEs developed more frequently a complete tumor regression than patients who died from other causes (P=0.018). Of note, ICIs-related myocarditis and pneumonitis were both associated with a systemic occurrence irAEs. Our study demonstrates that some irAEs, especially myocarditis, hypophysitis, and encephalitis are clinically underdiagnosed. Autopsy remains a valuable tool to monitor diagnostic accuracy and therapeutic side effects in patients who died under ICIs-therapy.

Icariin promoted ferroptosis by activating mitochondrial dysfunction to inhibit colorectal cancer and synergistically enhanced the efficacy of PD-1 inhibitors

BACKGROUND

A controlled type of cell death called ferroptosis is linked to increased reactive oxygen species (ROS), lipid peroxidation, and iron buildup. Furthermore, evidence indicates that ferroptosis may act as an immunogenic form of cell death with potential physiological functions in tumors and immunosuppression. Inducing ferroptosis in tumor cells may have the potential to complement cancer immunotherapy strategies. The development of colorectal cancer (CRC) and the poor efficacy of immunotherapy are associated with the crosstalk of cellular ferroptosis. Currently, Icariin (ICA), the main bioactive component extracted from Epimedium, has been shown to inhibit a variety of cancers. However, the specific role and potential mechanism of ICA in regulating ferroptosis in CRC remains unclear.

PURPOSE

The aim of this investigation was to clarify the mechanism underlying the anti-CRC cancer properties of ICA and how it induces ferroptosis to enhance immunotherapy.

METHODS

To evaluate cell viability, the Cell Counting Kit-8 (CCK-8) test was utilized. The transwell test and the wound healing assay were used to assess cell migration. A subcutaneous graft tumor model was constructed with C57BL/6 mice using MC38 colorectal cancer cell lines. The inhibitory effect of ICA on CRC, ferroptosis level and immunomodulatory effects were detected by serum biochemical assay, cytokine assay, hematoxylin-eosin (H&E) staining, immunofluorescence staining, CyTOF mass spectrometry flow screening and Western blotting. Western blotting, proteomics, molecular docking and microscale thermophoresis (MST) were used to forecast and confirm ICA's binding and interaction with HMGA2, STAT3, and HIF-1α. Moreover, the levels of lipid peroxidation and ferroptosis were assessed through the use of the C11-BODIPY fluorescent probe, the FerroOrange fluorescent probe, the iron level, the malondialdehyde (MDA) and reduced glutathione (GSH) assay kit, and Western blotting analysis. To assess alterations in mitochondrial structure and membrane potential, transmission electron microscopy (TEM) and JC-1 immunofluorescence were employed.

RESULTS

It was demonstrated in the current study that ICA treatment inhibits CRC and enhances anti-PD-1 therapy efficacy by inciting ferroptosis. As shown in vitro, ICA inhibits CRC cell proliferation, migration, and apoptosis. As demonstrated in vivo, ICA has a dose-dependent tumor suppressor effect when combined with anti-PD-1, it can significantly inhibit tumor growth, increase the expression of serum TNF-α, IFN-γ, and granzyme B, and promote CD69+CD8+ T, CD69+CD8+Tem, CD69+CD8+Teff, TCRβ+CD8+ T, TCRβ+CD8+ T, TCRβ+CD8+Tem, TCRβ+CD8+Teff. The inhibitory effect of ICA on CRC was associated with the binding of HMGA2, STAT3, and HIF-1α proteins, which inhibited CRC by increasing the levels of reactive oxygen species (ROS) and malondialdehyde (MDA), promoting the accumulation of iron (Fe2+), depletion of reduced glutathione (GSH), inhibiting SLC7A11 and GPX4 expressions, thereby inducing ferroptosis in CRC. As a consequence of ICA-induced ferroptosis, mitochondria are dysfunctional, with increased ROS production, membrane potential depolarization (MMP), and ATP production reduced. This process can be efficiently reversed by the mitochondria-targeted antioxidant Mito-Q. It is noteworthy that the ferroptosis inhibitor liproxstatin-1 (lip-1), anti-CD8, and anti-IFN-γ exhibited a significant inhibitory effect on the level of ferroptosis and antitumor capacity of ICA combined with anti-PD-1. This finding suggests that the antitumor immunopotentiating effect of ICA on anti-PD-1 is dependent on the secretion of IFN-γ-induced ferroptosis of CRC cells by the CD8+ T cell.

CONCLUSION

Our study represents the inaugural demonstration of the mechanism whereby ICA exerts anti-CRC effects and synergistically enhances the efficacy of anti-PD-1, inducing mitochondrial damage and leading to ferroptosis. ICA promotes ferroptosis of CRC cells by inducing mitochondrial dysfunction, and ICA combined with anti-PD-1 significantly promotes CD69, TCRβ signalling, activates effector CD8+ T cells to secrete IFN-γ, and achieves immunopotentiation by promoting ferroptosis of CRC cells, thus inhibiting CRC development. This study is built upon existing research into the pharmacodynamic mechanisms of ICA in the context of CRC, and offers a novel therapeutic approach in addressing the issue of CRC immunotherapy potentiation.

Development of pituitary dysfunction and destructive thyroiditis is associated with better survival in non-small cell lung cancer patients treated with programmed cell death-1 inhibitors: a prospective study with immortal time bias correction

Background

Immune-related adverse events (irAEs) are reported to be associated with better overall survival (OS) in non-small cell lung cancer (NSCLC) patients treated with immune checkpoint inhibitors. However, there may be a bias in that patients who develop irAEs must survive long enough to experience the irAEs, and no prospective studies adjusting for immortal time bias (ITB) have examined the relationship between OS and pituitary dysfunction or the two different types of thyroid dysfunction: destructive thyroiditis and hypothyroidism without prior thyrotoxicosis (isolated hypothyroidism).

Methods

Patients with NSCLC who received nivolumab or pembrolizumab at Nagoya University Hospital between November 2, 2015 and February 1, 2023 were enrolled. Endocrine irAEs were prospectively assessed during scheduled evaluations of hormone levels. The association between irAE development and survival when considering ITB was examined by time-dependent Cox regression analysis.

Results

Of the 194 patients included, 11 (5.7%), 10 (5.2%), and 5 (2.6%) developed pituitary dysfunction, destructive thyroiditis, and isolated hypothyroidism, respectively. The development of pituitary dysfunction (HR 0.36, 95% CI 0.13-0.98, p = 0.045) and destructive thyroiditis (HR 0.31, 95% CI 0.10-0.97, p = 0.044), but not isolated hypothyroidism (HR 1.15, 95% CI 0.42-3.20, p = 0.786), was significantly associated with longer OS.

Conclusion

NSCLC patients developing pituitary dysfunction and destructive thyroiditis showed better OS even after adjusting for ITB, suggesting that these irAEs indicate a better prognosis.

Immune checkpoint inhibitors-related thyroid dysfunction: influencing factor analysis, prediction model development, and management strategy proposal

BACKGROUND

With the extensive utilization of immune checkpoint inhibitors (ICIs) across various cancers, ICIs-related thyroid dysfunction (ICI-TD) has become a growing concern in clinical practice. This study aimed to devise an individualized management strategy for ICI-TD to enhance the early identification and proactive management in cancer patients.

METHODS

We designed and conducted a three-phase study. Initially, we analyzed the influencing factors through a systematic review and meta-analysis, which adhered to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Moreover, the study protocol was registered with PROSPERO (CRD42019131133). Subsequently, prediction models for ICI-TD were developed utilizing 11 algorithms based on the real-world cohort data from July 20, 2018 (the approval date of the first ICIs, Pembrolizumab in China), to October 31, 2022. Considering discrimination, calibration, and clinical utility, we selected the model with the best performance for web calculator development. Finally, individualized management strategies for ICI-TD were proposed by combining evidence-based analysis with practical considerations.

RESULTS

The systematic review encompassed 21 observational studies involving 4,145 patients, revealing associations between ICI-TD and factors such as female gender, age, receipt of Pembrolizumab (versus other ICIs), and baseline levels of thyroid-stimulating hormone, free thyroxine, and antithyroid antibodies. In the prediction model development phase, 621 participants were enrolled, with 36 patients developing ICI-TD. The model based on the LightGBM algorithm demonstrated superior performance, leading to the development of a web calculator. Based on these findings and existing guidelines, individualized monitoring and treatment pathways for pharmacists were devised.

CONCLUSION

This study offers comprehensive insights into managing ICI-TD, potentially enhancing tailored cancer immunotherapy management.

A Case of Uveitis and Hypothyroidism Following Pembrolizumab Therapy in a Patient With Plantar Malignant Melanoma

Pembrolizumab is a PD-1 inhibitor that has improved survival in melanoma patients but can cause immune-related adverse events (irAEs) such as hypothyroidism and uveitis. Although these conditions rarely occur together, we present a case of a 54-year-old female with plantar malignant melanoma who developed hypothyroidism after the second cycle of pembrolizumab and then uveitis after the fifth cycle. Hypothyroidism was treated with levothyroxine, and uveitis was managed with corticosteroids. This case highlights the importance of careful monitoring and multidisciplinary management of these adverse events during immunotherapy.

Enhancing cancer immunotherapy: Nanotechnology-mediated immunotherapy overcoming immunosuppression

Immunotherapy is an important cancer treatment method that offers hope for curing cancer patients. While immunotherapy has achieved initial success, a major obstacle to its widespread adoption is the inability to benefit the majority of patients. The success or failure of immunotherapy is closely linked to the tumor's immune microenvironment. Recently, there has been significant attention on strategies to regulate the tumor immune microenvironment in order to stimulate anti-tumor immune responses in cancer immunotherapy. The distinctive physical properties and design flexibility of nanomedicines have been extensively utilized to target immune cells (including tumor-associated macrophages (TAMs), T cells, myeloid-derived suppressor cells (MDSCs), and tumor-associated fibroblasts (TAFs)), offering promising advancements in cancer immunotherapy. In this article, we have reviewed treatment strategies aimed at targeting various immune cells to regulate the tumor immune microenvironment. The focus is on cancer immunotherapy models that are based on nanomedicines, with the goal of inducing or enhancing anti-tumor immune responses to improve immunotherapy. It is worth noting that combining cancer immunotherapy with other treatments, such as chemotherapy, radiotherapy, and photodynamic therapy, can maximize the therapeutic effects. Finally, we have identified the challenges that nanotechnology-mediated immunotherapy needs to overcome in order to design more effective nanosystems.

Combined use of tyrosine kinase inhibitors with PD-(L)1 blockade increased the risk of thyroid dysfunction in PD-(L)1 blockade: a prospective study

BACKGROUND

Anti-programmed cell death-1 (ligand-1) antibody [PD-(L)1-Ab] can cause destructive thyroiditis and/or hypothyroidism. In addition, tyrosine kinase inhibitors (TKIs) frequently induce hypothyroidism. The aim of this prospective study is to examine the incidence and clinical characteristics of thyroid dysfunction induced by combination therapy of a PD-(L)1-Ab and TKI [PD-(L)1-Ab/TKI].

METHODS

A total of 757 patients treated with PD-(L)1-Ab or PD-(L)1-Ab/TKI were evaluated for anti-thyroid antibodies (ATAs) at baseline and for thyroid function for 48 weeks after treatment initiation and then observed until the last visit.

RESULTS

The cumulative incidences of destructive thyroiditis [4/23 (17.4%) vs. 45/734 (6.1%) patients, p < 0.001], isolated hypothyroidism [10/23 (43.5%) vs. 29/734 (4.0%) patients, p < 0.001], and all thyroid dysfunction [14/23 (60.9%) vs. 74/734 (10.1%) patients, p < 0.001] were significantly higher in the PD-(L)1-Ab/TKI group than PD-(L)1-Ab group, respectively. All patients positive for ATAs at baseline developed thyroid dysfunction after PD-(L)1-Ab/TKI treatment, a significantly higher incidence than that in those negative for ATAs at baseline [4/4 (100%) vs. 10/19 (52.6%) patients, p = 0.026].

CONCLUSIONS

The addition of TKIs increased the risk of thyroid dysfunction induced by PD-(L)1-Ab, with the risk being higher in patients positive for baseline ATAs.

Is 18F-FDG-PET/CT an Optimal Imaging Modality for Detecting Immune-Related Adverse Events after Immune-Checkpoint Inhibitor Therapy? Pros and Cons

Immunotherapy with immune checkpoint inhibitors (ICIs) has revolutionized contemporary oncology, presenting efficacy in various solid tumors and lymphomas. However, ICIs may potentially overstimulate the immune system, leading to immune-related adverse events (irAEs). IrAEs may affect multiple organs, such as the colon, stomach, small intestine, kidneys, skin, lungs, joints, liver, lymph nodes, bone marrow, brain, heart, and endocrine glands (e.g., pancreas, thyroid, or adrenal glands), exhibiting autoimmune inflammation. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) is commonly used in oncology for staging and assessment of therapy responses, but it may also serve as a tool for detecting irAEs. This review aims to present various patterns of metabolic activation associated with irAEs due to ICI treatment, identifiable through 18F-FDG PET/CT. It describes the advantages of early detection of irAEs, but also presents the challenges in differentiating them from tumor progression. It also delves into aspects of molecular response assessment within the context of pseudoprogression and hyperprogression, along with typical imaging findings related to these phenomena. Lastly, it summarizes the role of functional PET imaging in oncological immunotherapy, speculating on its future significance and limitations.

Changes in TgAb and TPOAb titers are greater in thyrotoxicosis than isolated hypothyroidism induced by PD-1 blockade

Anti-thyroglobulin antibodies (TgAb) and/or anti-thyroid peroxidase antibodies (TPOAb) positivity at baseline is a risk marker for thyroid immune-related adverse events (thyroid-irAEs) in anti-programmed cell death-1 antibody (PD-1-Ab) treatment; however, it is unknown if TgAb and TPOAb titers are associated with clinical characteristics of thyroid-irAEs. Among 586 patients treated with PD-1-Ab at Nagoya University Hospital between 2 November 2015 and 30 September 2021, 57 patients developed thyroid-irAEs (thyrotoxicosis [n = 38]; hypothyroidism without prior thyrotoxicosis {isolated hypothyroidism} [n = 19]) in whom thyroid function, and TgAb and TPOAb titers were determined at baseline and at the onset. The changes in TgAb (median, 54.8 vs. 0.2 IU/mL; p = 0.002) and TPOAb titers (31.6 vs. 0 IU/mL; p = 0.032) from baseline to onset of developing thyroid-irAEs were greater in patients with thyrotoxicosis than patients with isolated hypothyroidism. Higher TgAb and TPOAb titers, and the TgAb titer at baseline were associated with an earlier onset of thyrotoxicosis and higher peak free thyroxine levels, respectively. Twenty-eight patients who developed hypothyroidism after thyrotoxicosis had higher TgAb (54.5 vs. 10.7 IU/mL; p = 0.011) and TPOAb titers at baseline (46.1 vs. 9.0 IU/mL; p < 0.001) and greater changes in TgAb (61.7 vs. 7.8 IU/mL; p = 0.025) and TPOAb titers (52.8 vs. -0.8 IU/mL; p < 0.001) than patients who did not develop hypothyroidism. The TgAb titer at baseline and changes in the TgAb and TPOAb titers were greater in patients with thyrotoxicosis than patients with isolated hypothyroidism, suggesting that the magnitude of the thyroid autoimmune response reflects the clinical types of thyroid-irAEs.

[Interdisciplinary Management of Orbital Diseases]

Diagnosis and therapy of orbital diseases is an interdisciplinary challenge, in which i.e. otorhinolaryngologists, ophthalmologists, radiologists, radiation therapists, maxillo-facial surgeons, endocrinologists, and pediatricians are involved. This review article describes frequent diseases which both, otolaryngologists and ophthalmologists are concerned with in interdisciplinary settings. In particular the inflammatory diseases of the orbit including orbital complications, autoimmunological diseases of the orbit including Grave´s orbitopathy, and primary and secondary tumors of the orbit are discussed. Beside describing the clinical characteristics and diagnostic steps the article focusses on the interdisciplinary therapy. The review is completed by the presentation of most important surgical approaches to the orbit, their indications and possible complications. The authors tried to highlight the relevant facts despite the shortness of the text.

Rapidly progressive interstitial lung disease with positive anti-MDA5 antibody as an immune-related complication of nivolumab: A case report

Clinically amyopathic dermatomyositis (CADM) with a positive anti-MDA5 antibody titer is often associated with lethal rapidly progressive interstitial lung disease (RP-ILD). Despite the widespread use of immune checkpoint inhibitors (ICIs) in practice, there is no report of CADM with positive anti-MDA5 antibodies as their immune-related complication. We present a case of malignant mesothelioma who developed RP-ILD accompanied by distinct skin manifestations following the administration of nivolumab. Postmortem assessment of stored samples revealed a pre-existing positive titer of anti-MDA5 antibody, further augmented following ICI use, suggesting the possible value of serum screening for better risk stratification of this lethal complication.

Immune-related adverse events in non-small cell lung cancer: Occurrence, mechanisms and therapeutic strategies

The emergence of immune checkpoint inhibitors (ICIs) has heralded a transformative era in the therapeutic landscape of non-small cell lung cancer (NSCLC). While ICIs have demonstrated clinical efficacy in a portion of patients with NSCLC, these treatments concurrently precipitate a spectrum of immune-related adverse events (irAEs), encompassing mild to severe manifestations, collectively posing a risk of significant organ damage. Consequently, there exists an imperative to augment our comprehension of the pathophysiological underpinnings of irAEs and to formulate more efficacious preventive and ameliorative strategies. In this comprehensive review, we delineate the clinical presentation of organ-specific irAEs in patients with NSCLC and provide an in-depth analysis of recent advancements in understanding the mechanisms driving ICI-induced toxicity. Furthermore, we discuss potential strategies and targets for ameliorating these irAEs. Ultimately, this review aims to furnish valuable insights to guide further research endeavours in the context of irAEs in NSCLC patients.

Inflammatory Profile Assessment in a Highly Selected Athyreotic Population Undergoing Controlled and Standardized Hypothyroidism

Background: Hypothyroidism (hT) presents heterogeneous symptoms and findings. Evidence on this topic comes mainly from heterogeneous populations in terms of disease duration, residual thyroid function, and comorbidities. Therefore, it would be useful to assess systemic inflammation in a homogeneous hT population. The aim of this study was to investigate inflammation in a population that underwent standardized controlled hT. Methods: We recruited thyroidectomized patients diagnosed with thyroid cancer who were otherwise fit and healthy, showing hypothyroidism before I131 treatment using a standard protocol of LT4 withdrawal. The blood inflammatory indexes (BIIXs) (i.e., NLR, PLR, MLR, SII, SIRI, and AISI) were calculated using the blood tests collected just before I131 administration. Patients were divided according to sex, BMI, and thyroglobulin. The relationships between the BIIXs, age, and thyroid hormones were also investigated. Results: We included 143 patients. The median age of the sample was 43 years. The BIIX median values showed significant differences based on sex, BMI, and thyroglobulin levels (p < 0.05). No significant correlations were found between the BIIXs and age, TSH, FT4, and FT3. Conclusions: This study shows the BIIX median values of a population which underwent standardized hT. It suggests a role for some BIIXs in the evaluation of hypothyroidism in obese people and as hypothetical prognostic markers for thyroid cancer.

Current Therapeutic Approaches for Graves' Orbitopathy - are Targeted Therapies the Future?

Graves' orbitopathy is an autoimmune disease of the orbit that most frequently occurs with Graves' hyperthyroidism. The occurrence of autoantibodies directed against the TSH receptor (TRAb) is of central importance for the diagnosis and pathogenesis. These autoantibodies are mostly stimulating, and induce uncontrolled hyperthyroidism and tissue remodelling in the orbit and more or less pronounced inflammation. Consequently, patients suffer to a variable extent from periocular swelling, exophthalmos, and fibrosis of the eye muscles and thus restrictive motility impairment with double vision. In recent decades, therapeutic approaches have mainly comprised immunosuppressive treatments and antithyroid drug therapy for hyperthyroidism to inhibit thyroid hormone production. With the recognition that TRAb also activates an important growth factor receptor, IGF1R (insulin-like growth factor 1 receptor), biological agents have been developed. Teprotumumab (an inhibitory IGF1R antibody) has already been approved in the USA and the therapeutic effects are enormous, especially with regard to the reduction of exophthalmos. Side effects are to be considered, especially hyperglycaemia and hearing loss. It is not yet clear whether the autoimmune reaction (development of the TRAb/attraction of immunocompetent cells) is also influenced by anti-IGF1R inhibiting agents. Recurrences after therapy show that the inhibition of antibody development must be included in the therapeutic concept, especially in severe cases.

Endocrine Adverse Events Related To Immune Checkpoint Inhibitor Treatment: Relationship Between Antibodies and Severity of Thyroid Dysfunction

OBJECTIVE

The purpose of this study was to identify predictive and risk factors for the development of immune-related endocrinopathies and to analyze the incidence and characteristics of immune-related endocrinopathies in our population.

DESIGN

A retrospective, single-centre cohort carried out at Gregorio Marañón Hospital between January 2018 -December 2019.

METHODS

A total of 163 patients were enrolled. In January 2018 and December 2019, we treated patients who underwent ICI treatment in the Medical Oncology Department of General University Hospital Gregorio Marañón, a tertiary care public hospital in Madrid, as part of an observational, retrospective, single-center cohort study.

RESULTS

Endocrinopathies were diagnosed in 19.5% of the patients (n = 32). The tumours with the highest incidence of endocrinopathies were non-small cell lung cancer (25,9%), kidney cell cancer (25%) and hepatocarcinoma (20%). Among the 32 patients who developed endocrinopathy, 18,8%, 19,13%, and 21,28% received anti-CTLA-4, anti-PD-1 and anti-PDL-1, respectively. Thyroid dysfunction was the most frequent endocrinopathy (12,8%). A higher percentage of patients with negative antiTPO and antiTG antibodies developed G1 hypothyroidism compared to patients with positive antibodies who developed a higher proportion of G2 hypothyroidism. The presence of an initial phase of thyrotoxicity was not related to greater severity. We observed longer progression-free survival in patients who developed thyroid dysfunction.

CONCLUSION

Pre-existing antibodies were independently associated with endocrinopathies. Moreover, our study let us conclude that the presence of thyroid autoantibodies may be related to its severity. It is important to determine anti-thyroid antibodies prior to the start of immunotherapy as a risk factor for thyroid dysfunction, which in turn is a prognostic marker.

Toxicity spectrum and risk factors for chemo-immunotherapy in locally advanced or metastatic lung cancer

Chemo-immunotherapy has become the best first-line treatment for advanced lung cancer patients without oncogenic drivers. However, it may also lead to an increased incidence and severity of treatment-related adverse events. In this retrospective study, lung cancer patients administrated with either anti-PD-1 or anti-PD-L1 treatment plus chemotherapy were included. Data on demographic characteristics, disease characteristics, treatment strategies, laboratory results, and clinical outcomes were collected from the Electronic Medical Records System and evaluation scales. Chi-square, univariate, and multivariate logistic regression analyses were used to identify the risk factors for immune-related adverse events (irAEs). A total of 116 patients were included in the study, and the majority experienced treatment-related adverse events. Adverse events of any grade were reported in 114 (98.3%) patients, with 73 (62.9%) experiencing Grade 3 or higher events. The most frequent adverse events were anemia (67.2%), decreased appetite (62.9%), and alopecia (53.4%). Fifty-four (46.6%) patients were diagnosed with irAEs, with hypothyroidism (28.4%) being the most commonly reported. Multivariable analysis demonstrated a significant correlation between the number of treatment cycles, elevated baseline levels of thyroid stimulating hormone (TSH) and interleukin-6 (IL-6) with irAEs (OR = 1.222, P = 0.009, OR = 1.945, P = 0.016, OR = 1.176, P = 0.004), and IL-6 was identified as a strong predictor of severe irAEs (OR = 1.084, P = 0.014). Our study demonstrated the safety of chemo-immunotherapy in lung cancer patients without additional toxicity. The number of treatment cycles, higher baseline levels of TSH and IL-6 were identified as potential clinical biomarkers for irAEs.

Immune-related thyroid dysfunctions during anti PD-1/PD-L1 inhibitors: new evidence from a single centre experience

The role of anti-thyroid peroxidase antibodies (anti-TPO Abs) in the development of abnormal thyroid function tests (DYSTHYR) during treatment with immune checkpoint inhibitors (ICIs) is not fully understood; moreover, controversial data exist about the relationship between ICI-related thyroid dysfunction (TD) and survival. We retrospectively analyzed the onset or the worsening of DYSTHYR in patients treated with programmed cell death protein-1 (PD-1) or its ligand (PD-L1) inhibitors between 2017 and 2020. In patients without previous TD, we focused on the association between baseline anti-TPO Abs level and DYSTHYR. Furthermore, the relationship between DYSTHYR and progression-free survival (PFS) or overall survival (OS) was explored. We included 324 patients treated with anti PD-1 (95.4%) or anti PD-L1 inhibitors. After a median of 3.3 months, DYSTHYR was registered in 24.7%, mostly hypothyroidism alone (17%). Patients with pre-existing TD (14.5% of the sample) were at higher risk of DYSTHYR compared to patients without previous TD (adjusted OR 2.44; 95% IC 1.26-4.74). In patients without known previous TD, high anti-TPO Abs level, even below the positivity cut-off, was a risk factor for developing DYSTHYR (adjusted OR 5.52; 95% IC 1.47-20.74). DYSTHYR was associated with a longer 12-month OS (87.3% vs 73.5%, p = 0.03); no statistically significant difference in terms of PFS was observed between the DYSTHYR+ and DYSTHYR- group. DYSTHYR is common during anti PD-1/anti PD-L1 treatment, especially in patients with pre-existing TD. In subjects without known previous TD, high anti-TPO Abs level at baseline can be a predictive biomarker of DYSTHYR. An improved OS is observed in patients with anti PD-1/anti PD-L1-induced DYSTHYR.

Mechanisms and biomarkers of immune-related adverse events in gastric cancer

Immune-checkpoint inhibitors (ICIs), different from traditional cancer treatment models, have shown unprecedented anti-tumor effects in the past decade, greatly improving the prognosis of many malignant tumors in clinical practice. At present, the most widely used ICIs in clinical immunotherapy for a variety of solid tumors are monoclonal antibodies against cytotoxic T lymphocyte antigen-4 (CTLA-4), programmed cell death protein 1 (PD-1) and their ligand PD-L1. However, tumor patients may induce immune-related adverse events (irAEs) while performing immunotherapy, and irAE is an obstacle to the prospect of ICI treatment. IrAE is a non-specific disease caused by immune system imbalance, which can occur in many tissues and organs. For example, skin, gastrointestinal tract, endocrine system and lung. Although the exact mechanism is not completely clear, related studies have shown that irAE may develop through many ways. Such as excessive activation of autoreactive T cells, excessive release of inflammatory cytokines, elevated levels of autoantibodies, and common antigens between tumors and normal tissues. Considering that the occurrence of severe IrAE not only causes irreversible damage to the patient's body, but also terminates immunotherapy due to immune intolerance. Therefore, accurate identification and screening of sensitive markers of irAE are the main beneficiaries of ICI treatment. Additionally, irAEs usually require specific management, the most common of which are steroids and immunomodulatory therapies. This review aims to summarize the current biomarkers for predicting irAE in gastric cancer and their possible mechanisms.

Hyperthyroidism: A Review

Importance

Overt hyperthyroidism, defined as suppressed thyrotropin (previously thyroid-stimulating hormone) and high concentration of triiodothyronine (T3) and/or free thyroxine (FT4), affects approximately 0.2% to 1.4% of people worldwide. Subclinical hyperthyroidism, defined as low concentrations of thyrotropin and normal concentrations of T3 and FT4, affects approximately 0.7% to 1.4% of people worldwide. Untreated hyperthyroidism can cause cardiac arrhythmias, heart failure, osteoporosis, and adverse pregnancy outcomes. It may lead to unintentional weight loss and is associated with increased mortality.

Observations

The most common cause of hyperthyroidism is Graves disease, with a global prevalence of 2% in women and 0.5% in men. Other causes of hyperthyroidism and thyrotoxicosis include toxic nodules and the thyrotoxic phase of thyroiditis. Common symptoms of thyrotoxicosis include anxiety, insomnia, palpitations, unintentional weight loss, diarrhea, and heat intolerance. Patients with Graves disease may have a diffusely enlarged thyroid gland, stare, or exophthalmos on examination. Patients with toxic nodules (ie, in which thyroid nodules develop autonomous function) may have symptoms from local compression of structures in the neck by the thyroid gland, such as dysphagia, orthopnea, or voice changes. Etiology can typically be established based on clinical presentation, thyroid function tests, and thyrotropin-receptor antibody status. Thyroid scintigraphy is recommended if thyroid nodules are present or the etiology is unclear. Thyrotoxicosis from thyroiditis may be observed if symptomatic or treated with supportive care. Treatment options for overt hyperthyroidism from autonomous thyroid nodules or Graves disease include antithyroid drugs, radioactive iodine ablation, and surgery. Treatment for subclinical hyperthyroidism is recommended for patients at highest risk of osteoporosis and cardiovascular disease, such as those older than 65 years or with persistent serum thyrotropin level less than 0.1 mIU/L.

Conclusions and Relevance

Hyperthyroidism affects 2.5% of adults worldwide and is associated with osteoporosis, heart disease, and increased mortality. First-line treatments are antithyroid drugs, thyroid surgery, and radioactive iodine treatment. Treatment choices should be individualized and patient centered.

Risk of Thyroid Dysfunction in PD-1 Blockade Is Stratified by the Pattern of TgAb and TPOAb Positivity at Baseline

CONTEXT

Positive antithyroglobulin (TgAb) and/or antithyroid peroxidase antibodies (TPOAb) at baseline indicate a high risk of thyroid immune-related adverse events (irAEs) induced by antiprogrammed cell death-1 antibodies (anti-PD-1-Ab). However, whether the positivity patterns of both antibodies are associated with the risk of thyroid irAEs is unknown.

OBJECTIVE

The aim of the present study was to clarify the association of the pattern of TgAb and TPOAb positivity at baseline with the risk of thyroid irAEs induced by anti-PD-1-Ab.

METHODS

Patients (n = 516) were evaluated for TgAb and TPOAb at baseline and prospectively for thyroid function every 6 weeks for 24 weeks after initiating anti-PD-1-Ab.

RESULTS

Fifty-one (9.9%) patients developed thyroid irAEs (thyrotoxicosis in 34, hypothyroidism without prior thyrotoxicosis in 17). Twenty-five patients subsequently developed hypothyroidism following thyrotoxicosis. The cumulative incidence of thyroid irAEs differed among 4 groups classified by the presence of TgAb/TPOAb at baseline (group 1: TgAb-(-)/TPOAb-(-), 4.6% [19/415]; group 2: TgAb-(-)/TPOAb-(+), 15.8% [9/57]; group 3: TgAb-(+)/TPOAb-(-), 42.1% [8/19]; group 4: TgAb-(+)/TPOAb-(+), 60.0% [15/25]) as follows: groups 1 vs 2-4 (P ≤ .001) and groups 2 vs 3 (P = .008) and 4 (P < .001). There were different incidences of thyrotoxicosis (groups 1-4, 3.1%, 5.3%, 31.6%, 48.0%, respectively; P < .001) in groups 1 vs 3 and 4, and groups 2 vs 3 and 4, and of hypothyroidism (groups 1-4: 2.9%, 15.8%, 31.6%, 60.0%, respectively; P < .001) in groups 1 vs 2 to 4, and groups 2 vs 4.

CONCLUSION

The risk of thyroid irAEs was affected by the pattern of TgAb and TPOAb positivity at baseline; there were high risks of thyrotoxicosis in patients with TgAb-(+) and of hypothyroidism in patients with TgAb-(+) and those with TPOAb-(+).

Mitogen-Activated Protein Kinase and Nuclear Hormone Receptor Crosstalk in Cancer Immunotherapy

The three major MAP-kinase (MAPK) pathways, ERK1/2, p38 and JNK/SAPK, are upstream regulators of the nuclear "hormone" receptor superfamily (NHRSF), with a prime example given by the estrogen receptor in breast cancer. These ligand-activated transcription factors exert non-genomic and genomic functions, where they are either post-translationally modified by phosphorylation or directly interact with components of the MAPK pathways, events that govern their transcriptional activity towards target genes involved in cell differentiation, proliferation, metabolism and host immunity. This molecular crosstalk takes place not only in normal epithelial or tumor cells, but also in a plethora of immune cells from the adaptive and innate immune system in the tumor-stroma tissue microenvironment. Thus, the drugability of both the MAPK and the NHRSF pathways suggests potential for intervention therapies, especially for cancer immunotherapy. This review summarizes the existing literature covering the expression and function of NHRSF subclasses in human tumors, both solid and leukemias, and their effects in combination with current clinically approved therapeutics against immune checkpoint molecules (e.g., PD1).

Reduced Tumor Size of Untreated Papillary Thyroid Carcinoma After Immune Checkpoint Inhibitor-Induced Thyroiditis

Background/Objective

Immune checkpoint inhibitors (CPIs) activate antitumoral immune responses and are used to treat multiple types of primary and metastatic malignancies. Thyroid dysfunction is a known immune-related adverse event of CPI therapy. There are few data on the effect of CPI and CPI-induced thyroiditis on primary papillary thyroid carcinoma (PTC). We present a patient who developed CPI-induced thyroiditis during treatment for a nonthyroid malignancy and subsequent regression of a coexisting untreated primary PTC.

Case Report

A 49-year-old man with metastatic colon adenocarcinoma was found to have a large right thyroid nodule with biopsy confirmation of PTC. He did not have compressive symptoms or evidence of metastatic PTC. Resection was not performed because of colon cancer therapy. Treatment with CPI (ezabenlimab, an anti-programmed cell death protein 1 antibody) was initiated for the treatment of colon cancer. Four months after the initiation of CPI therapy, testing showed thyroid-stimulating hormone and free thyroxine levels of 174.9 (0.3-4.0 mIU/L) and 0.67 (0.93-1.70 ng/dL), respectively, consistent with CPI-induced hypothyroidism. Levothyroxine therapy was initiated. Repeat imaging 3 months later demonstrated a decrease in the tumor size to 4.1 × 4.9 × 4.2 cm (calculated volume change, -8.3% from baseline). At the last imaging, 1 year after the onset of CPI-induced thyroiditis, the PTC continued to decrease in size and measured 2.9 × 3.9 × 3.2 cm (volume change, -60.7% from baseline).

Discussion

CPI-induced thyroiditis suggests the development of an immune response against thyroid tissue and may reflect a similar increased immune response against PTC cells leading to tumor regression in this case.

Conclusion

Further research to assess the immunologic mechanism underlying this association is warranted to potentially develop improved immunotherapy for PTC.

Isolated autoimmune adrenocorticotropic hormone deficiency: A positive predictor of survival among cancer patients treated with checkpoint inhibitors

OBJECTIVE

We aimed to characterize cancer patients who developed isolated adrenocorticotrophic hormone (ACTH) deficiency (IAD) after treatment with checkpoint-inhibitors (CPIs), including clinical manifestations, laboratory findings and risk factors, and to evaluate the prognostic significance of this complication.

DESIGN

A retrospective case-control study.

METHODS

We conducted a retrospective analysis of 2225 cancer patients treated with CPIs between 2015 and 2021 in our institute. We identified a subgroup of patients with sub-normal cortisol levels due to ACTH deficiency, and comprehensively extracted all relevant data. We compared the patients survival rates using a log-rank test and a multi-variable Cox regression.

RESULTS

Among 2225 patients, hypocortisolemia was documented in 99 (4.45%) patients, and 19 of them were diagnosed with IAD (0.85%). Asthenia and diarrhea were the most reported complaints (36.8%), and melanoma was the most common malignancy (68.42%) within the IAD group. In multivariable analysis, IAD was associated with better survival rates (p = .018), female gender (63.2% vs 40%, p = .041), treatment with Ipilimumab (57.9% vs. 19.4%, p < .001), and younger age (median 56 IQR 51-69, vs. median 69 IQR 60-76, p = .004).

CONCLUSIONS

IAD is the dominant autoimmune etiology for cortisol deficiency among patients receiving immunotherapy and is reported for the first time as a positive predictor of survival among cancer patients treated with CPIs. In our patients, IAD development was associated with female gender, treatment with ipilimumab, and younger age.

Increased plasma levels of soluble programmed death ligand 1 (sPD-L1) and fibroblast growth factor 23 (FGF-23) in patients with Graves' ophthalmopathy in comparison to hyperthyroid patients without Graves' ophthalmopathy

BACKGROUND

Management of Graves' ophthalmopathy (GO) is still a challenge in Graves' disease (GD). Moreover, 40% of GD patients show radiological muscle enlargement without clinically apparent GO. Delayed treatment of GO may lead to deterioration in prognosis.

METHODS

Thirty GD patients with overt hyperthyroidism were included in this study, 17 of whom either had GO at diagnosis or developed GO during the study period. Samples were collected at the beginning of the study, at 6 months, and at 24 months. Plasma samples were analyzed for 92 cytokines using the Olink Target 96 inflammation panel.

RESULTS

After adjustment for multiplicity testing using the false discovery rate approach, soluble programmed death ligand 1 (sPD-L1) and fibroblast growth factor 23 (FGF-23) were significantly elevated in GO patients.

CONCLUSION

Using a broad cytokine panel we show that patients with Graves' ophthalmopathy have elevated PD-L1 and FGF-23 levels. The findings support previous suggestions that PD-L1 may serve as a treatment target.

Endocrine Side Effects in Patients Treated with Immune Checkpoint Inhibitors: A Narrative Review

Checkpoint inhibitors are monoclonal antibodies that elicit an anti-tumor response by stimulating immune system. Their use has improved the treatment of different types of cancer such as melanoma, breast carcinoma, lung, stomach, colon, liver, renal cell carcinoma, and Hodgkin's lymphoma, but several adverse events have been reported. Although the etiology of these effects is not completely understood, an uncontrolled activation of the immune system has been postulated. Indeed, some studies showed a cross reactivity of T cells, which acted against tumor antigens as well as antigens in the tissues of patients who developed immune-related adverse events. Despite the known possibility of developing immune-related adverse events, early diagnosis, monitoring during therapy, and treatment are fundamental for the best supportive care and administration of immune checkpoint inhibitors. The aim of this review is to guide the clinician in early diagnosis, management, and treatment of the endocrinological adverse effects in the major endocrine glands (thyroid, pituitary, adrenal, endocrine pancreas, and parathyroid).

Immune checkpoint inhibitor-induced hypothyroidism predicts treatment response in Japanese subjects

Background

Immune checkpoint inhibitors (ICIs) cause a variety of immune-related adverse events (irAEs). Among them, thyroid dysfunction is most frequently observed. Patients with irAEs have higher survival rates than those without irAEs, but there is no certainty as to whether the degree of thyroid dysfunction is associated with treatment response or survival with ICIs.

Method

This is a single-center, retrospective, observational study. The study included 466 patients who received ICI at Kawasaki Medical School Hospital from September 1, 2014, to May 31, 2022 and evaluated the degree of abnormal thyroid function and survival and remission rates after treatment with ICIs. Primary hypothyroidism of less than 10 μIU/mL TSH was classified as grade 1, and primary hypothyroidism requiring more than 10 μIU/mL TSH or levothyroxine as grade 2-4.

Result

The mean age of the study participants was 68.2 ± 10.3 years, and the percentage of male participants was 72.6%. The frequency of ICI-induced thyroid dysfunction in the study participants was 28.2%. TSH levels were significantly higher in Grade 1 and Grades 2-4 when treated with ICI compared to NTF (p<0.0001). The survival rate at 1 year after ICI administration was significantly higher with 64.9% for grade 1 and 88.9% for grades 2-4 compared to 52.1% for NTF (p<0.0001). Cancer stage at the time of ICI administration did not differ among the groups (p=0.68). Nevertheless, the remission rate assessed by RECIST criteria was significantly higher in grades 2-4 compared to NTF (p<0.0001).

Conclusion

ICI-induced thyroid dysfunction was significantly correlated with survival, mean observation time, and treatment remission rate. It is important to monitor thyroid hormone levels regularly in patients receiving ICIs.

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

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

Permanent hypothyroidism following immune checkpoint inhibitors induced thyroiditis may be associated with improved survival: results of an exploratory study

Background

Immune-related endocrinopathies are common after immune checkpoint inhibitor (ICI) therapy, among which destructive thyroiditis is the most prevalent. Improved survival outcomes have been associated with immune-related adverse events. We aimed to compare the clinical course and biochemical parameters of two subtypes of ICI-related destructive thyroiditis: a transient thyrotoxicosis that reverts to either euthyroidism (TT; transient thyroiditis) versus progression to permanent hypothyroidism (PH), and to identify prognostic markers in cancer patients receiving ICI therapy who developed DT.

Methods

This retrospective observational study included 124 patients who developed a transient thyrotoxicosis due to a destructive thyroiditis after ICI therapy from January 1, 2016 to April 30, 2021 at the Montefiore Medical Center. Patients were categorized as either TT or PH based on spontaneous renormalization of the TSH or the permanent need for thyroid hormone replacement, respectively. Thyroid hormone and antibody levels, serum inflammatory markers, eosinophils, and metabolic uptake of the thyroid on PET imaging, each corresponding closest to a suppressed TSH, were characterized. Survival from TT and PH were also analyzed.

Results

Of the 124 patients, 53 developed PH and 71 developed TT. The PH group developed thyrotoxicosis at a median of 42 days from the first ICI dose while the TT group took significantly longer at 56 days. Thyroidal PET uptake was increased in 18.9% of the PH group versus 6.0% of the TT group (P=0.04). Three different survival models consistently demonstrated a trend towards increased survival in the PH group, compared to the TT group.

Conclusion

Our results suggest that PH developing after ICI-induced destructive thyroiditis may be associated with a more robust inflammatory and antitumor response to ICI therapy. The results suggests that PH may be a potential clinical predictor of improved survival.

Preconditioning of the immune system modulates the response of papillary thyroid cancer to immune checkpoint inhibitors

BACKGROUND

The response of solid tumors such as papillary thyroid cancer (PTC) to immune checkpoint inhibitors (ICIs) is highly variable. The biological basis of this variability remains unknown.

METHODS

To test the hypothesis that preconditioning of the immune system modulates the therapeutic effect of ICIs, we used a murine model where PTC and iodine exacerbated thyroiditis (IET) can be induced in a temporally predictable fashion. A total of 122 mice were divided into 3 experimental groups. In the first one, named concomitant IET and PTC (No.=40), IET, and PTC were induced at the same time; in the second one, named pre-existing IET (No.=44), IET was induced prior to the induction of PTC; in the third one, named no IET (No.=38), only PTC was induced. Following disease induction, mice of each group were treated with anti-PD-1 antibody, anti-lymphocyte activation gene 3 antibody (anti-Lag3), anti-T-cell immunoglobulin and mucin domain 3 antibody (anti-Tim3), or IgG control. Ten weeks after the initial ICI injection, mice were sacrificed to collect the thyroid gland for histological analysis, to quantify the incidence and burden of PTC, and to perform high-throughput single-cell RNA sequencing of infiltrating CD45⁺ cells.

RESULTS

In the concomitant IET and PTC group, ICI treatment reduced PTC incidence (p=0.002 comparing treatment with any ICI vs control), while it had no effect in the pre-existing IET and no IET groups. Single-cell sequencing of thyroidal CD45⁺ cells showed that the different ICIs tested had both specific and shared effects on all the components of the thyroidal immune cell infiltrate. The shared effect of the tested ICIs was dependent on the presence of pre-existing versus concomitant IET. In the context of concomitant IET, ICI treatment resulted in the modulation of a greater number of pathways related to both innate and adaptive immunity.

CONCLUSIONS

Response to ICIs depends on the status of the immune system of the treated individual. Modulation of the immune system should be explored as a tool to improve response to ICIs in patients with PTC or other forms of cancer.

Drug Repurposing to Enhance Antitumor Response to PD-1/PD-L1 Immune Checkpoint Inhibitors

Monoclonal antibodies targeting the PD-1/PD-L1 immune checkpoint have considerably improved the treatment of some cancers, but novel drugs, new combinations, and treatment modalities are needed to reinvigorate immunosurveillance in immune-refractory tumors. An option to elicit antitumor immunity against cancer consists of using approved and marketed drugs known for their capacity to modulate the expression and functioning of the PD-1/PD-L1 checkpoint. Here, we have reviewed several types of drugs known to alter the checkpoint, either directly via the blockade of PD-L1 or indirectly via an action on upstream effectors (such as STAT3) to suppress PD-L1 transcription or to induce its proteasomal degradation. Specifically, the repositioning of the approved drugs liothyronine, azelnidipine (and related dihydropyridine calcium channel blockers), niclosamide, albendazole/flubendazole, and a few other modulators of the PD-1/PD-L1 checkpoint (repaglinide, pimozide, fenofibrate, lonazolac, propranolol) is presented. Their capacity to bind to PD-L1 or to repress its expression and function offer novel perspectives for combination with PD-1 targeted biotherapeutics. These known and affordable drugs could be useful to improve the therapy of cancer.