Targeting the mTOR pathway uncouples the efficacy and toxicity of PD-1 blockade in renal transplantation

Association of thrombocytopenia with immune checkpoint inhibitors: a large-scale pharmacovigilance analysis based on the data from FDA adverse event reporting system database

Introduction: An increasing number of immune-related adverse events (irAEs) induced by immune checkpoint inhibitors (ICIs) have been reported during clinical treatment. We aimed to explore the clinical characteristics of patients with ICIs-induced ITP under different therapeutic strategies based on the FAERS database and explore the potential biological mechanisms in combination with TCGA pan-cancer data. Methods: Data from FAERS were collected for ICIs adverse reactions between January 2012 and December 2022. Disproportionality analysis identified ICIs-induced ITP in the FAERS database using the reporting odds ratio (ROR), proportional reporting ratio (PRP), Bayesian confidence propagation neural network (BCPNN), and multi-item gamma Poisson shrinker algorithms (MGPS). The potential biological mechanisms underlying ITP induced by ICIs were examined using TCGA transcriptome data on cancers. Results: In the FAERS, 345 ICIs-induced ITP reports were retrieved, wherein 290 (84.06%) and 55 (15.94%) were reported as monotherapy and combination therapy, respectively. The median age of the reported patients with ICIs-induced ITP was 69 years (IQR 60-76), of which 62 (18%) died and 47 (13.6%) had a life-threatening outcome. The majority of reported indications were lung, skin, and bladder cancers, and the median time to ITP after dosing was 42 days (IQR 17-135), with 64 patients (43.5%) experiencing ITP within 30 days of dosing and 88 patients experiencing ITP in less than 2 months (59.9%). The occurrence of ICIs-induced ITP may be associated with ICIs-induced dysregulation of the mTORC1 signaling pathway and megakaryocyte dysfunction. Conclusion: There were significant reporting signals for ITP with nivolumab, pembrolizumab, cemiplimab, atezolizumab, avelumab, durvalumab, ipilimumab, nivolumab/ipilimumab, and pembrolizumab/ipilimumab. Patients treated with anti-PD-1 in combination with anti-CTLA-4 are more likely to have an increased risk of ICIs-induced ITP. Patients with melanoma are at a higher risk of developing ITP when treated with ICI and should be closely monitored for this risk within 60 days of treatment. The potential biological mechanism of ICIs-induced ITP may be related to the dysfunction of megakaryocyte autophagy through the overactivation of the mTOR-related signaling pathway. This study provides a comprehensive understanding of ICIs-induced ITP. Clinicians should pay attention to this potentially fatal adverse reaction.

Immunosuppression in liver transplant oncology: position paper of the Italian Board of Experts in Liver Transplantation (I-BELT)

Liver transplant oncology (TO) represents an area of increasing clinical and scientific interest including a heterogeneous group of clinical-pathological settings. Immunosuppressive management after LT is a key factor relevantly impacting result. However, disease-related guidance is still lacking, and many open questions remain in the field. Based on such a substantial lack of solid evidences, the Italian Board of Experts in Liver Transplantation (I-BELT) (a working group including representatives of all national transplant centers), unprecedently promoted a methodologically sound consensus conference on the topic, based on the GRADE approach. The group final recommendations are herein presented and commented. The 18 PICOs and Statements and their levels of evidence and grades of recommendation are reported and grouped into seven areas: (1) risk stratification by histopathological and bio-molecular parameters and role of mTORi post-LT; (2) steroids and HCC recurrence; (3) management of immunosuppression when HCC recurs after LT; (4) mTORi monotherapy; (5) machine perfusion and HCC recurrence after LT; (6) physiopathology of tumor-infiltrating lymphocytes and immunosuppression, the role of inflammation; (7) immunotherapy in liver transplanted patients. The interest in mammalian targets of rapamycin inhibitors (mTORi), for steroid avoidance and the need for a reduction to CNI exposure emerged from the consensus process. A selected list of unmet needs prompting further investigations have also been developed. The so far heterogeneous and granular approach to immunosuppression in oncologic patients deserves greater efforts for a more standardized therapeutic response to the different clinical scenarios. This consensus process makes a first unprecedented step in this direction, to be developed on a larger scale.

Rapamycin Induces Phenotypic Alterations in Oral Cancer Cells That May Facilitate Antitumor T Cell Responses

OBJECTIVES

In this study, we investigated the antitumor immunomodulatory effects of rapamycin in oral cancer.

STUDY DESIGN

We examined the proliferation, apoptosis, and migration of cancer cells and investigated the cell surface expression levels of immune accessory molecules and T cell immune responses in vitro. We investigated the effect of in vivo administration of rapamycin on immune cell distribution and T cell immune responses in oral tumor-bearing mice.

RESULTS

Rapamycin treatment significantly inhibited OSCC cell proliferation and migration, increased apoptotic cell death, and upregulated cell surface expression of several immune accessory and adhesion molecules, including CD40, CD83, PD-L1, PD-L2, MHC class I, P-selectin, and VCAM-1. These cancer cells augmented T cell proliferation. In vivo rapamycin administration significantly attenuated mouse tumor growth with an increased proportion of immune cells, including CD4+ T cells, CD8+ T cells, and dendritic cells (DCs); decreased the proportion of immune suppressive cells, such as myeloid-derived suppressor cells and regulatory T cells; enhanced DC maturation and upregulated the surface expression of CD40, CD86, and ICAM-1.

CONCLUSIONS

Our results suggest that the therapeutic effect of mTOR inhibition in oral cancer can cause direct antitumor and immunomodulatory effects.

Primary prophylaxis with mTOR inhibitor enhances T cell effector function and prevents heart transplant rejection during talimogene laherparepvec therapy of squamous cell carcinoma

The application of mammalian target of rapamycin inhibition (mTORi) as primary prophylactic therapy to optimize T cell effector function while preserving allograft tolerance remains challenging. Here, we present a comprehensive two-step therapeutic approach in a male patient with metastatic cutaneous squamous cell carcinoma and heart transplantation followed with concomitant longitudinal analysis of systemic immunologic changes. In the first step, calcineurin inhibitor/ mycophenolic acid is replaced by the mTORi everolimus to achieve an improved effector T cell status with increased cytotoxic activity (perforin, granzyme), enhanced proliferation (Ki67) and upregulated activation markers (CD38, CD69). In the second step, talimogene laherparepvec (T-VEC) injection further enhances effector function by switching CD4 and CD8 cells from central memory to effector memory profiles, enhancing Th1 responses, and boosting cytotoxic and proliferative activities. In addition, cytokine release (IL-6, IL-18, sCD25, CCL-2, CCL-4) is enhanced and the frequency of circulating regulatory T cells is increased. Notably, no histologic signs of allograft rejection are observed in consecutive end-myocardial biopsies. These findings provide valuable insights into the dynamics of T cell activation and differentiation and suggest that timely initiation of mTORi-based primary prophylaxis may provide a dual benefit of revitalizing T cell function while maintaining allograft tolerance.

Bifidobacterium modulation of tumor immunotherapy and its mechanism

The advent of tumor immunotherapy in patients has revolutionized the treatment of tumors and significantly improved survival rates for a wide range of tumors. However, the full therapeutic potential of immune checkpoint inhibitors (ICIs) has yet to be realized, as not all patients have a lasting survival benefit from them, and a significant proportion of patients show primary or acquired resistance to immunotherapy. Bifidobacterium is one of the most common probiotics, and its antitumor and immunomodulatory effects have been demonstrated in recent years, but its immunomodulatory effects in tumors, especially on ICIs and in combination, have not been extensively studied in clinical practice, and its effects on the immune system and the mechanisms that modulate immunotherapy are largely unknown. Therefore, this review will focus on the immunomodulatory effects of Bifidobacteria in malignancies and the possible mechanisms of action of Bifidobacteria on immunotherapy in the hope of providing a basis for further research and better application of Bifidobacteria in clinical practice.

Fine-tuning tumor- and allo-immunity: advances in the use of immune checkpoint inhibitors in kidney transplant recipients

Cancer is a common complication after kidney transplantation. Kidney transplant recipients (KTR) have a 2- to 4-fold higher risk of developing cancer compared to the general population and post-transplant malignancy is the third most common cause of death in KTR. Moreover, it is well known that certain cancer types are overrepresented after transplantation, especially non-melanoma skin cancer. Immune checkpoint inhibitors (ICI) have revolutionized the treatment of cancer, with remarkable survival benefit in a subgroup of patients. ICI are monoclonal antibodies that block the binding of specific co-inhibitory signaling molecules. Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4), programmed cell death protein 1 (PD-1), and its ligand programmed cell death ligand 1 (PD-L1) are the main targets of ICI. Solid organ transplant recipients (SOTR) have been excluded from clinical trials owing to concerns about tumor response, allo-immunity, and risk of transplant rejection. Indeed, graft rejection has been estimated as high as 48% and represents an emerging problem. The underlying mechanisms of organ rejection in the context of treatment with ICI are poorly understood. The search for restricted antitumoral responses without graft rejection is of paramount importance. This review summarizes the current knowledge of the use of ICI in KTR, the potential mechanisms involved in kidney graft rejection during ICI treatment, potential biomarkers of rejection, and how to deal with rejection in clinical practice.

Cemiplimab for Kidney Transplant Recipients With Advanced Cutaneous Squamous Cell Carcinoma

PURPOSE

Cemiplimab is approved for treating locally advanced or metastatic cutaneous squamous cell carcinoma (CSCC). Solid organ transplant recipients have been excluded from immunotherapy trials, given concern for allograft rejection despite their increased risk of skin cancers. Chronic immunosuppression is necessary to prevent organ rejection but may attenuate antitumor response with PD-1 inhibitors.

METHODS

We report a phase I study of cemiplimab for kidney transplant recipients (KTRs) with advanced CSCC. After cross-taper to a mammalian target of rapamycin (mTOR) inhibitor and pulsed dose corticosteroids (prednisone 40 mg once daily, the day before and on days 1-3 of each cycle, followed by 20 mg once daily on days 4-6, then 10 mg once daily until the day before each subsequent cycle), patients received cemiplimab 350 mg intravenously once every 3 weeks for up to 2 years and were assessed for response every 8 weeks. The primary end point was the rate of kidney rejection, with key secondary end points including rate and duration of response, and survival.

RESULTS

Twelve patients were treated. No kidney rejection or loss was observed. A response to cemiplimab was observed in five of 11 evaluable patients (46%; 90% CI, 22 to 73), including two with durable responses beyond a year. Median follow-up was 6.8 months (range, 0.7-29.8). Treatment-related grade 3 or greater adverse events occurred in five patients (42%), including diarrhea, infection, and metabolic disturbances. One patient died of angioedema and anaphylaxis attributed to mTOR inhibitor cross-taper.

CONCLUSION

mTOR inhibitor and corticosteroids represent a favorable immunosuppressive regimen for KTRs with advanced CSCC receiving immunotherapy. This combination resulted in durable antitumor responses with no kidney rejection events (funded by Regeneron Pharmaceuticals [ClinicalTrials.gov identifier: NCT04339062]).

Durable complete response to early immunotherapy discontinuation in a kidney transplant recipient with advanced cutaneous squamous cell carcinoma: A case report and review of literature

BACKGROUND

The usage of immunotherapy to treat skin malignancies in transplant patients requires weighing the risk of acute organ transplant rejection with the potential reduction of antitumor efficacy by transplant immunosuppression. Reducing the duration of immune checkpoint inhibitor treatment may help prevent acute transplant rejection and late immune-related adverse events.

CASE PRESENTATION

An allogenic kidney transplant patient who developed regionally metastatic cutaneous squamous cell carcinoma received four cycles of pembrolizumab with complete response to therapy. Therapy was discontinued due to fatigue, significant cancer response, and to reduce the risk of acute graft rejection. His renal function remained stable, and he achieved subsequent durable response after treatment discontinuation.

CONCLUSION

Organ transplant recipients with complete response to immunotherapy for cutaneous squamous cell carcinoma may continue to respond despite early treatment cessation. This may reduce the risks of late immune-related adverse events and acute graft rejection.

Programmed cell death ligand 1 expression associated with subtypes of post-transplant lymphoproliferative disorder among pediatric kidney transplant recipients

BACKGROUND

Programmed cell death ligand 1 (PD-L1) expression on tumor cells engages the PD-1 receptor on T cells, inhibiting anti-tumor responses. PD-L1 has been detected in cases of post-transplant lymphoproliferative disorder (PTLD) but reports are limited. Here we examine PD-L1 expression and evaluate for clinical correlations.

METHODS

Twenty-one cases of PTLD were identified among pediatric kidney transplant recipients at our institution from February 1996 to April 2017. Using paraffin-embedded tissue biopsies, we examined 21 primary tumors for expression using PD-L1 monoclonal antibody performed with PAX5 as a double stain. We scored expression of PD-L1 on lesional B-cells as a percentage of positive cells. Clinical course and outcome were obtained from retrospective chart review.

RESULTS

Applying revised 2017 WHO PTLD classification showed five non-destructive, nine polymorphic, and seven monomorphic cases. Average PD-L1 expression based upon PTLD subtype was: non-destructive 11%, polymorphic 43%, and monomorphic 73% (p = .01). Two patients transferred shortly after diagnosis, five received chemotherapy, and three died from PTLD. Among the fatalities, all showed monomorphic PTLD and 90% of lesional B-cells expressed PD-L1.

CONCLUSION

In this case series, significant differences in PD-L1 expression were seen among different subtypes, and monomorphic PTLD demonstrated the highest expression. Study of a larger cohort is needed, and if the correlation of PD-L1 expression and PTLD subtype is confirmed, this may highlight the potential utility of checkpoint inhibitor therapy in cases of severe or refractory disease among kidney transplant recipient in whom the risk of allograft loss is acceptable given the option of chronic dialysis.

Developing Strategies to Improve the Efficacy of CAR-T Therapy for Acute Myeloid Leukemia

OPINION STATEMENT

Acute myeloid leukemia (AML) is a fatal blood malignancy. With the development of immunotherapy, particularly chimeric antigen receptor T cells (CAR-T), the treatment of AML has undergone a significant change. Despite its advantages, CAR-T still faces a number of limitations and challenges while treating AML. Finding novel targets, altering the structure of CAR to increase efficacy while lowering side effects, and using double-target CAR and logic circuits are typical examples of key to answer these problems. With the advancement of gene editing technology, gene editing of tumor cells or normal cells to create therapeutic effects has grown in popularity. Additionally, the combination of multiple drugs is routinely used to address some of the obstacles and difficulties associated with CAR-T therapy. The review's primary goal was to summarize recent strategies and developments of CAR-T therapy for AML.

Use of immune checkpoint inhibitors in solid organ transplant recipients with advanced cutaneous malignancies

Background

Immune checkpoint inhibitors (ICI) are standard of care therapy for patients with cutaneous malignancies, the most frequently diagnosed cancers in solid organ transplant (SOT) recipients. The activity and rate of allograft rejection in SOT recipients with advanced skin cancers treated with ICI is understudied.

Methods

We conducted a retrospective analysis of SOT recipients with advanced melanoma, cutaneous squamous cell carcinoma (cSCC), and merkel cell carcinoma (MCC) who were treated with ICI. Unpublished cases from our institution and published cases from the literature were aggregated. Demographics, type of immunosuppressive therapy, type of ICI(s) administered, prior systemic therapies, tumor response to ICI, and evidence of organ rejection and/or failure were recorded. Objective response rates (ORR) and rates of graft rejection and failure are reported.

Results

Ninety patients were identified; four patients from our institution and 86 unique patients from a literature review. ORR to first-line ICI for the entire cohort was 41.1% (37/90). ORR by tumor type was 31% (18/58), 64.3% (18/28), and 25.0% (1/4) for melanoma, cSCC, and MCC, respectively. The rate of graft rejection was 37.8% (34/90) with 61.8% (21/34) of these cases progressing to graft failure. Number of immunosuppressive agents (0, 1, 2, or 3) was inversely associated with rate of graft failure.

Conclusions

In this retrospective analysis, ICIs demonstrate clinical activity in SOT recipients with cutaneous malignancies; however, the rate of graft rejection is high. Treatment plans should be individualized through thorough interdisciplinary discussion. Immunosuppressive modifications may be considered prior to starting treatment, but when feasible, enrollment on clinical trials is preferred.

Immune Checkpoint Inhibitors in Solid Organ Transplant Recipients With Advanced Skin Cancers-Emerging Strategies for Clinical Management

Use of immune checkpoint inhibitors (ICIs) in solid organ transplant recipients (SOTRs) with advanced skin cancers presents a significant clinical management dilemma. SOTRs and other immunosuppressed patients have been routinely excluded from ICI clinical trials with good reason: immune checkpoints play an important role in self- and allograft-tolerance and risk of acute allograft rejection reported in retrospective studies affects 10% to 65% of cases. These reports also confirm that cutaneous squamous cell carcinoma and melanoma respond to ICI therapy, although response rates are generally lower than those observed in immunocompetent populations. Prospective trials are now of critical importance in further establishing ICI efficacy and safety. However, based on current knowledge, we recommend that ICIs should be offered to kidney transplant recipients with advanced cutaneous squamous cell carcinoma, melanoma, or Merkel cell carcinoma if surgery and/or radiotherapy have failed. For kidney transplant recipients, this should be first line ahead of chemotherapy and targeted therapies. In SOTRs, the use of ICIs should be carefully considered with the benefits of ICIs versus risks of allograft rejection weighed up on a case-by-case basis as part of shared decision-making with patients. In all cases, parallel management of immunosuppression may be key to ICI responsiveness. We recommend maintaining immunosuppression before ICI initiation with a dual immunosuppressive regimen combining mammalian target of rapamycin inhibitors and either corticosteroids or calcineurin inhibitors. Such modification of immunosuppression must be considered in the context of allograft risk (both rejection and also its subsequent treatment) and risk of tumor progression. Ultimately, a multidisciplinary approach should underpin all clinical decision-making in this challenging scenario.

2,5-dimethylcelecoxib alleviated NK and T-cell exhaustion in hepatocellular carcinoma via the gastrointestinal microbiota-AMPK-mTOR axis

BACKGROUND

2,5-dimethylcelecoxib (DMC), a derivative of celecoxib, is an inhibitor of microsomal prostaglandin E synthase-1 (mPGES-1). Our previous studies have demonstrated that DMC inhibits the expression of programmed death-ligand 1 on hepatocellular carcinoma (HCC) cells to prevent tumor progression. However, the effect and mechanism of DMC on HCC infiltrating immune cells remain unclear.

METHODS

In this study, single-cell-based high-dimensional mass cytometry was performed on the tumor microenvironment of HCC mice treated with DMC, celecoxib and MK-886 (a known mPGES-1 inhibitor). Moreover, 16S ribosomal RNA sequencing was employed to analyze how DMC improved the tumor microenvironment of HCC by remodeling the gastrointestinal microflora.

RESULTS

We found that (1) DMC significantly inhibited the growth of HCC and improved the prognosis of the mice, and this depended on the stronger antitumor activity of natural killer (NK) and T cells; (2) compared with celecoxib and MK-886, DMC significantly enhanced the cytotoxic and stem-like potential, and inhibited exhaustion of NK and T cells; (3) mechanistically, DMC inhibited the expression of programmed cell death protein-1 and upregulated interferon-γ expression of NK and T cells via the gastrointestinal microbiota (Bacteroides acidifaciens, Odoribacter laneus, and Odoribacter splanchnicus)-AMPK-mTOR axis.

CONCLUSIONS

Our study uncovers the role of DMC in improving the tumor microenvironment of HCC, which not only enriches the relationship between the mPGES-1/prostaglandin E2 pathway and the antitumor function of NK and T cells, but also provide an important strategic reference for multitarget or combined immunotherapy of HCC.Cite Now.

Immune Checkpoint Inhibitors in Breast Cancer: A Narrative Review

Breast cancer is the most frequently diagnosed malignancy in patients worldwide and the main cause of cancer-related death. Though still incurable, metastatic breast cancer's prognosis has been considerably improved in the past 10 years due to the introduction of new targeted agents, such as immune checkpoint inhibitors (ICI). However, these medications are associated with unique side effects known as immune-mediated adverse events (irAE). In this paper, we review the clinical evidence for the use of ICIs in breast cancer, in both the metastatic as well as neoadjuvant/adjuvant setting, followed by a review of irAE most commonly seen, and the medications used to treat them. Our opinion is that any cancer specialist treating patients with breast cancer should be aware of these side effects for early detection and management, and oncologists should be the leaders of the multidisciplinary team that will take care of them.

Allograft rejection following immune checkpoint inhibitors in solid organ transplant recipients: A safety analysis from a literature review and a pharmacovigilance system

AIM

This study aimed to systematically characterize transplant rejection after immune checkpoint inhibitors (ICIs) initiation in solid organ transplant recipients (SOTRs).

METHODS

Data were extracted from the US FDA Adverse Event Reporting System (FAERS) database and case reports in the literature. Disproportionality analysis including information component and reported odds ratio (ROR) was performed to access potential risk signals.

RESULTS

A total of 168 patients with transplant rejection after ICIs usage were identified in the FAERS database, and 89 cases were identified in the literature review. ICIs were significantly associated with transplant rejection (ROR₀₂₅ : 2.2). A strong risk signal was found for combination therapy with pembrolizumab and ipilimumab compared to monotherapy.

CONCLUSION

Immune checkpoint inhibitors were significantly associated with transplant rejection in SOTRs.

Small-Molecule Compounds Boost CAR-T Cell Therapy in Hematological Malignancies

OPINION STATEMENT

Although chimeric antigen receptor T cell immunotherapy has been successfully applied in patients with hematological malignancies, several obstacles still need to be overcome, such as high relapse rates and side effects. Overcoming the limitations of CAR-T cell therapy and boosting the efficacy of CAR-T cell therapy are urgent issues that must be addressed. The exploration of small-molecule compounds in combination with CAR-T cell therapies has achieved promising success in pre-clinical and clinical studies in recent years. Protein kinase inhibitors, demethylating drugs, HDAC inhibitors, PI3K inhibitors, immunomodulatory drugs, Akt inhibitors, mTOR inhibitors, and Bcl-2 inhibitors exhibited potential synergy in combination with CAR-T cell therapy. In this review, we will discuss the recent application of these combination therapies for improved outcomes of CAR-T cell therapy.

Blood Sample Processing and Banking for Functional and Molecular Analyses

Immune monitoring of circulating immune cells in the blood provides insight into a patient's own immune response over the course of a treatment or disease progression. Information such as whether immune cells are functional or non-functional and what specific proteins they express or secrete can be essential to understand if (and how) a treatment is working or a disease is progressing. To do so, it requires careful handling and storage of precious biological samples with the goals of obtaining a large amount of information from limited samples and minimizing future research costs by the use of banked samples. Many factors, including blood sample types, time of collection, containers used, preservatives and other additives, transport means, and length of transit time, all affect the quality of the samples and the stability of biomarkers and must be considered at the initial collection stage. An efficient study design includes provisions for further processing of the original samples, such as cryopreservation of isolated cells, purification of DNA and RNA, and preparation of specimens for genomic, immunological, and biochemical analyses. Development of standard operating procedures and quality control plans is a safeguard of the samples' quality and of the validity of the results. Here, we focus on the collection and processing of blood suitable for plasma and peripheral blood mononuclear cell (PBMC) banking, including collection, processing, and storage of samples, based on our experience.

Immunotherapy for hepatocellular carcinoma recurrence after liver transplantation, can we harness the power of immune checkpoint inhibitors?

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death globally and liver transplantation (LT) can serve as the best curative treatment option. However, HCC recurrence after LT remains the major obstacle to the long-term survival of recipients. Recently, immune checkpoint inhibitors (ICIs) have revolutionized the treatment of many cancers and provided a new treatment strategy for post-LT HCC recurrence. Evidence has been accumulated with the real-world application of ICIs in patients with post-LT HCC recurrence. Notably, the use of these agents as immunity boosters in recipients treated with immunosuppressors is still controversial. In this review, we summarized the immunotherapy for post-LT HCC recurrence and conducted an efficacy and safety evaluation based on the current experience of ICIs for post-LT HCC recurrence. In addition, we further discussed the potential mechanism of ICIs and immunosuppressive agents in regulating the balance between immune immunosuppression and lasting anti-tumor immunity.

Current landscape and tailored management of immune-related adverse events

Unprecedented advances have been made in immune checkpoint inhibitors (ICIs) in the treatment of cancer. However, the overall benefits from ICIs are impaired by the increasing incidence of immune-related adverse events (irAEs). Although several factors and mechanisms have been proposed in the development of irAEs, there is still incomprehensive understanding of irAEs. Therefore, it is urgent to identify certain risk factors and biomarkers that predict the development of irAEs, as well as to understand the underlying mechanisms of these adverse events. Herein, we comprehensively summarize the state-of-the-art knowledge about clinical features and the related risk factors of irAEs. Particularly, we also discuss relevant mechanisms of irAEs and address the mechanism-based strategies, aiming to develop a tailored management approach for irAEs.

Acute Kidney Injury in Cancer Immunotherapy Recipients

Cancer immunotherapy has now entered clinical practice and has reshaped the standard of care for many cancer patients. With these new strategies, specific toxicities have emerged, and renal side effects have been described. In this review, we will describe the causes of acute kidney injury in CAR T cell, immune checkpoint inhibitors and other cancer immuno-therapy recipients. CAR T cell therapy and bispecific T cell engaging antibodies can lead to acute kidney injury as a consequence of cytokine release syndrome, tumor lysis syndrome, sepsis or specific CAR T cell infiltration. Immune checkpoint blockade most often results in acute tubular interstitial nephritis, but glomerular diseases have also been described. Although the pathophysiology remains mostly elusive, we will describe the mechanisms of renal damage in these contexts, its prognosis and treatment. As the place of immunotherapy in the anti-cancer armamentarium is exponentially increasing, close collaboration between nephrologists and oncologists is of utmost importance to provide the best standard of care for these patients.

The role of immune checkpoints in cardiovascular disease

Immune checkpoint inhibitors (ICI) are monoclonal antibodies which bind to immune checkpoints (IC) and their ligands to prevent inhibition of T-cell activation by tumor cells. Currently, multiple ICI are approved targeting Cytotoxic T-lymphocyte antigen 4 (CTLA-4), Programmed Death Protein 1 (PD-1) and its ligand PD-L1, and Lymphocyte-activation gene 3 (LAG-3). This therapy has provided potent anti-tumor effects and improved prognosis for many cancer patients. However, due to systemic effects, patients can develop immune related adverse events (irAE), including possible life threatening cardiovascular irAE, like atherosclerosis, myocarditis and cardiomyopathy. Inhibition of vascular IC is associated with increased atherosclerotic burden and plaque instability. IC protect against atherosclerosis by inhibiting T-cell activity and cytokine production, promoting regulatory T-cell differentiation and inducing T-cell exhaustion. In addition, PD-L1 on endothelial cells might promote plaque stability by reducing apoptosis and increasing expression of tight junction molecules. In the heart, IC downregulate the immune response to protect against cardiac injury by reducing T-cell activity and migration. Here, inhibition of IC could induce life-threatening T-cell-mediated-myocarditis. One proposed purpose behind lymphocyte infiltration is reaction to cardiac antigens, caused by decreased self-tolerance, and thereby increased autoimmunity because of IC inhibition. In addition, there are several reports of ICI-mediated cardiomyopathy with immunoglobulin G expression on cardiomyocytes, indicating an autoimmune response. IC are mostly known due to their cardiotoxicity. However, t his review compiles current knowledge on mechanisms behind IC function in cardiovascular disease with the aim of providing an overview of possible therapeutic targets in prevention or treatment of cardiovascular irAEs.

Identification of COL1A1 associated with immune infiltration in brain lower grade glioma

Brain low grade gliomas (LGG) often give serious clinical symptoms due to the invasion towards nervous system, affecting the life quality of patients. Collagen type I alpha 1(COL1A1) is the main component of type I collagen. Although there are many reports about abnormal expression of COL1A1 in various tumors, specific role and clinical significance of COL1A1 in LGG have not yet been elucidated. In this work, Tumor Immune Estimation Resource database was used for detecting the expression level of COL1A1 in cancer and normal tissues, and aimed to explore the relationship between COL1A1 and tumor immune infiltration. We applied Kaplan-Meier to analyze the role of COL1A1 in clinical prognosis. Univariate survival rate and multivariate Cox analysis were used to compare clinical characteristics and survival rate. The relativity between the expression of COL1A1 and the tumor microenvironment was evaluated using ESTIMATE algorithm. Finally, the relationship between expression level of COL1A1 and gene marker sets of immune cell infiltration was investigated via TIMER. According to TCGA, COL1A1 overexpression was correlated with overall survival (OS), progression free interval (PFI) and disease specific survival (DSS) of multiple tumors, especially in LGG. Multivariate analysis showed that COL1A1 expression was an independent prognostic factor for LGG. The expression of COL1A1 was positively correlated with the infiltration of CD4 + T and CD8 + T cells, neutrophils, macrophages and dendritic cells in LGG. In addition, there was a strong correlation between expression of COL1A1 and different immune marker sets in LGG. The results suggest that COL1A1 is related with tumor immune infiltration of LGG.

Immune checkpoint inhibitors for solid organ transplant recipients: clinical updates

Transplant care continues to advance with increasing clinical experience and improvements in immunosuppressive therapy. As the population ages and long-term survival improves, transplant patient care has become more complex due to comorbidities, frailty, and the increased prevalence of cancer posttransplantation. Immune checkpoint inhibitors (ICIs) have become a standard treatment option for many cancers in non-transplant patients, but the use of ICIs in transplant patients is challenging due to the possibility of disrupting immune tolerance. However, over the past few years, ICIs have gradually started to be used in transplant patients as well. In this study, we review the current use of ICIs after all solid organ transplantation procedures (kidney, liver, heart, and lung). Increasing data suggest that the type and number of immunosuppressants may affect the risk of rejection after immunotherapy. Immunotherapy for cancer in transplant patients may be a feasible option for selected patients; however, prospective trials in specific organ transplant recipients are needed.

Novel strategies for the mitigation of cytokine release syndrome induced by T cell engaging therapies with a focus on the use of kinase inhibitors

T cell engaging therapies, like CAR-T cells and T cell engagers, redirect T cells toward tumor cells, facilitating the formation of a cytotoxic synapse and resulting in subsequent tumor cell killing. T cell receptor or CAR-T downstream signaling triggers a release of pro-inflammatory cytokines, which can induce a Cytokine Release Syndrome (CRS). The incidence of CRS is still hardly predictable among individuals and remains one of the major dose-limiting safety liabilities associated with on-target activity of T cell engaging therapies. This emphasizes the need to elaborate mitigation strategies, which reduce cytokine release while retaining efficacy. Here, we review pre-clinical and clinical approaches applied for the management of CRS symptoms in the context of T cell engaging therapies, highlighting the use of tyrosine kinase inhibitors as an emerging mitigation strategy. In particular, we focus on the effects of Bruton's tyrosine kinase (BTK), Src family including Lck, mammalian target of rapamycin (mTOR) and Janus tyrosine kinase (JAK) inhibitors on T cell functionality and cytokine release, to provide a rationale for their use as mitigation strategies against CRS in the context of T cell engaging therapies.

Immune Checkpoint Inhibitor Use in Solid Organ Transplant Recipients: A Systematic Review

Chronic immunosuppression in solid organ transplant recipients (SOTRs) leads to an increased risk of a wide variety of cancers. Immune checkpoint inhibitor (ICI) therapy is indicated for many of these; however, the risks and benefits of ICI use in the SOTR population have not been well characterized. We performed a systematic literature review identifying 119 reported cases of ICI use among SOTRs. Treatments used included PD-1 inhibition (75.6%), CTLA-4 inhibition (12.6%), PD-L1 inhibition (1.7%), and combination and/or sequential ICI therapy (10.1%). The most common cancers included cutaneous melanoma (35.3%), hepatocellular carcinoma (22.7%), and cutaneous squamous cell carcinoma (18.5%). The overall objective response rate (ORR) was 34.5%, with a median duration of response of 8.0 months. Ongoing response was seen in 21.0%. Cutaneous squamous cell carcinoma had significantly better ORR compared with other cancer types (68.2% vs 26.8%; odds ratio [OR], 5.85; P =.0006). Factors associated with improved ORR included increasing time from transplant to ICI (OR, 1.09; P =.008) and preemptive reduction in intensity of the graft maintenance immunosuppressive regimen (50.0% vs 18.5%; OR, 4.40; P =.0088). Rejection occurred in 41.2%, graft failure in 23.5%, and immune-related adverse events in 18.5%. Factors significantly associated with allograft rejection included allograft PD-L1 positivity (100% vs 0%; P<.0001) and absence of tacrolimus in the immunosuppressive regimen (48.7% vs 25.6%; OR, 0.36; P =.019). The most common cause of death was progressive malignancy (64.0%), followed by graft failure (24.0%). Our analysis provides current benchmark data to help inform management of SOTRs with advanced cancers that are reflected by our patient cohort. Biomarker development, more robust datasets, and prospective study of concomitant immunosuppression management may help refine decision-making in this complex scenario in the future. Close coordination of care between the medical oncologist and transplant specialist is encouraged to help optimize treatment outcomes.

Spectrum of Nonkeratinocyte Skin Cancer Risk Among Solid Organ Transplant Recipients in the US

Importance

Nonkeratinocyte skin cancers are an important cause of morbidity and mortality for immunosuppressed solid organ transplant recipients (SOTRs), but the spectrum of disease and risk factor characteristics are unknown.

Objective

To characterize the spectrum of disease and risk factors for common and rare nonkeratinocyte skin cancers in SOTRs.

Design, Setting, and Participants

This population-based cohort study included 444 497 SOTRs who underwent a transplant in the US between January 1, 1987, and December 31, 2017, using linked data from the national transplant registry and 32 cancer registries. Data analysis was conducted from April 1, 2021, to September 30, 2021.

Main Outcomes and Measures

Standardized incidence ratios (SIRs) were used to assess risk relative to the general population, and Poisson regression was used to evaluate risk factors.

Results

A total of 2380 nonkeratinocyte skin cancers were identified among 444 497 SOTRs (median age at transplant, 50 years; range, 0-96 years; 274 276 [61.7%] male; 272 241 [61.2%] non-Hispanic White). Melanoma was the most common cancer (1471 [61.8%]), followed by Merkel cell carcinoma (334 [14.0%]), Kaposi sarcoma (186 [7.8%]), sebaceous carcinoma (170 [7.1%]), and cutaneous lymphomas (108 [4.5%]). Risks were most strongly elevated for cancers associated with viruses, including Kaposi sarcoma (SIR, 20.5; 95% CI, 17.7-23.7), Merkel cell carcinoma (SIR, 16.2; 95% CI, 14.5-18.1), and extranodal natural killer/T-cell lymphoma (SIR, 44.3; 95% CI, 5.37-160). Risks were also significantly elevated for sebaceous carcinoma (SIR, 15.2; 95% CI, 13.0-17.7), anaplastic large cell lymphoma (SIR, 6.82; 95% CI, 4.53-9.85), and diffuse large B-cell lymphoma (SIR, 5.17; 95% CI, 3.28-7.76). Several characteristics were independently associated with greater risk for multiple skin cancer types, including male sex, older age at transplant, factors associated with UV radiation exposure (non-Hispanic White race and ethnicity, living in an area with higher UV radiation exposure, and posttransplant diagnosis of keratinocyte carcinoma), and increasing time since transplantation. Treatment with mammalian target of rapamycin inhibitors was associated with reduced melanoma incidence (incidence rate ratio, 0.75; 95% CI, 0.57-0.98). A total of 847 skin cancers (39.4%) occurred on the head and neck.

Conclusions and Relevance

The findings of this cohort study suggest that viruses, UV radiation exposure, and immunosuppression are associated with the development of skin cancer in SOTRs. Certain high-risk subgroups may benefit from increased skin surveillance, and treatment with mammalian target of rapamycin inhibitors could be effective for melanoma chemoprevention in the transplant population.

A Patient With Failed Liver Transplantation After the Use of PD-1 Blockade Combined With Lenvaxen

Hepatocellular carcinoma (HCC) is a common malignant tumor with high extent of invasiveness. Its invasion process is closely related to complex tumor microenvironment and microvascular characteristics. Recently, immune combined targeted therapy has been applied to patients, combination therapy program with better effect needs to be explored. Atezolizumab combined Bevacizumab regimen in phase III clinical trial IMbrave150 was approved by U.S. Federal Drug Administration (FDA) for HCC treatment. This program is mostly used for liver malignant tumors have failed other treatments. Patients in terminal stage, overall curative has an unsatisfactory effect, survival time of patients is limited. Therefore, seeking best plan for combined treatment to improve patient's life quality and survival rate are still one of the most important clinical difficulties. This report describes a 37-year-old male who suffered from HCC repeatedly relapsed after hepatectomy. The patient received transcatheter arterial chemoembolization (TACE), microwave ablation (MWA), targeted therapy, and other combined treatments, all showed poor treatment effects. He received liver transplantation (LT) after receiving PD-1 blockade combined targeted therapy, eventually died due to severe immune rejection. It's first case of an allogeneic liver transplantation patient who received PD-1 blockade and Lenvaxen combined therapy. PD-1 blockade treatment and clinical observations of this case were summarized.

T-cell Exhaustion in Organ Transplantation

Exhaustion of T cells occurs in response to long-term exposure to self and foreign antigens. It limits T cell capacity to proliferate and produce cytokines, leading to an impaired ability to clear chronic infections or eradicate tumors. T-cell exhaustion is associated with a specific transcriptional, epigenetic, and metabolic program and characteristic cell surface markers' expression. Recent studies have begun to elucidate the role of T-cell exhaustion in transplant. Higher levels of exhausted T cells have been associated with better graft function in kidney transplant recipients. In contrast, reinvigorating exhausted T cells by immune checkpoint blockade therapies, while promoting tumor clearance, increases the risk of acute rejection. Lymphocyte depletion and high alloantigen load have been identified as major drivers of T-cell exhaustion. This could account, at least in part, for the reduced rates of acute rejection in organ transplant recipients induced with thymoglobulin and for the pro-tolerogenic effects of a large organ such as the liver. Among the drugs that are widely used for maintenance immunosuppression, calcineurin inhibitors have a contrasting inhibitory effect on exhaustion of T cells, while the influence of mTOR inhibitors is still unclear. Harnessing or encouraging the natural processes of exhaustion may provide a novel strategy to promote graft survival and transplantation tolerance.

Potential therapies for immune-related adverse events associated with immune checkpoint inhibition: from monoclonal antibodies to kinase inhibition

The therapeutic benefits of immune checkpoint inhibitors (ICIs), which enable antitumor immune responses, can be tempered by unwanted immune-related adverse events (irAEs). Treatment recommendations stratified by irAE phenotype and immunohistopathological findings have only recently been proposed and are often based on those used in primary autoimmune diseases, including targeting of specific proinflammatory cytokines with monoclonal antibodies. Increasing evidence supports the use of such antibody-based strategies as effective steroid-sparing treatments, although the therapies themselves may be associated with additional drug toxicities and reduced ICI efficacy. Kinases are key contributors to the adaptive and innate responses that drive primary autoimmune diseases and irAEs. The janus kinase/signal transducer and activator of transcription, Bruton’s tyrosine kinase, and mitogen-activated protein kinase-interacting serine/threonine protein kinases 1 and 2 pathways are also critical to tumor progression and have important roles in cells of the tumor microenvironment. Herein, we review the histopathological, biological, and clinical evidence to support specific monoclonal antibodies and kinase inhibition as management strategies for irAEs.

Identification of Master Regulators Driving Disease Progression, Relapse, and Drug Resistance in Lung Adenocarcinoma

Backgrounds: Lung cancer is the leading cause of cancer related death worldwide. Current treatment strategies primarily involve surgery, chemotherapy, radiotherapy, targeted therapy, and immunotherapy, determined by TNM stages, histologic types, and genetic profiles. Plenty of studies have been trying to identify robust prognostic gene expression signatures. Even for high performance signatures, they usually have few shared genes. This is not totally unexpected, since a prognostic signature is associated with patient survival and may contain no upstream regulators. Identification of master regulators driving disease progression is a vital step to understand underlying molecular mechanisms and develop new treatments.

Methods: In this study, we have utilized a robust workflow to identify potential master regulators that drive poor prognosis in patients with lung adenocarcinoma. This workflow takes gene expression signatures that are associated with poor survival of early-stage lung adenocarcinoma, EGFR-TKI resistance, and responses to immune checkpoint inhibitors, respectively, and identifies recurrent master regulators from seven public gene expression datasets by a regulatory network-based approach.

Results: We have found that majority of the master regulators driving poor prognosis in early stage LUAD are cell-cycle related according to Gene Ontology annotation. However, they were demonstrated experimentally to promote a spectrum of processes such as tumor cell proliferation, invasion, metastasis, and drug resistance. Master regulators predicted from EGFR-TKI resistance signature and the EMT pathway signature are largely shared, which suggests that EMT pathway functions as a hub and interact with other pathways such as hypoxia, angiogenesis, TNF-α signaling, inflammation, TNF-β signaling, Wnt, and Notch signaling pathways. Master regulators that repress immunotherapy are enriched with MYC targets, E2F targets, oxidative phosphorylation, and mTOR signaling.

Conclusion: Our study uncovered possible mechanisms underlying recurrence, resistance to targeted therapy, and immunotherapy. The predicted master regulators may serve as potential therapeutic targets in patients with lung adenocarcinoma.

JAK and mTOR inhibitors prevent cytokine release while retaining T cell bispecific antibody in vivo efficacy

Background

T cell engaging therapies, like chimeric antigen receptor T cells and T cell bispecific antibodies (TCBs), efficiently redirect T cells towards tumor cells, facilitating the formation of a cytotoxic synapse and resulting in subsequent tumor cell killing, a process that is accompanied by the release of cytokines. Despite their promising efficacy in the clinic, treatment with TCBs is associated with a risk of cytokine release syndrome (CRS). The aim of this study was to identify small molecules able to mitigate cytokine release while retaining T cell-mediated tumor killing.

Methods

By screening a library of 52 Food and Drug Administration approved kinase inhibitors for their impact on T cell proliferation and cytokine release after CD3 stimulation, we identified mTOR, JAK and Src kinases inhibitors as potential candidates to modulate TCB-mediated cytokine release at pharmacologically active doses. Using an in vitro model of target cell killing by human peripheral blood mononuclear cells, we assessed the effects of mTOR, JAK and Src kinase inhibitors combined with 2+1 T cell bispecific antibodies (TCBs) including CEA-TCB and CD19-TCB on T cell activation, proliferation and target cell killing measured by flow cytometry and cytokine release measured by Luminex. The combination of mTOR, JAK and Src kinase inhibitors together with CD19-TCB was evaluated in vivo in non-tumor bearing stem cell humanized NSG mice in terms of B cell depletion and in a lymphoma patient-derived xenograft (PDX) model in humanized NSG mice in terms of antitumor efficacy.

Results

The effect of Src inhibitors differed from those of mTOR and JAK inhibitors with the suppression of CD19-TCB-induced tumor cell lysis in vitro, whereas mTOR and JAK inhibitors primarily affected TCB-mediated cytokine release. Importantly, we confirmed in vivo that Src, JAK and mTOR inhibitors strongly reduced CD19-TCB-induced cytokine release. In humanized NSG mice, continuous treatment with a Src inhibitor prevented CD19-TCB-mediated B cell depletion in contrast to mTOR and JAK inhibitors, which retained CD19-TCB efficacy. Ultimately, transient treatment with Src, mTOR and JAK inhibitors minimally interfered with antitumor efficacy in a lymphoma PDX model.

Conclusions

Taken together, these data support further evaluation of the use of Src, JAK and mTOR inhibitors as prophylactic treatment to prevent occurrence of CRS.

Immunotherapy in liver transplantation for hepatocellular carcinoma: Pros and cons

Liver transplantation (LT) has emerged as a curative strategy for hepatocellular carcinoma (HCC), but contributes to a higher predisposition to HCC recurrence in the immunosuppression context, especially for tumors beyond the Milan criteria. Although immunotherapy has dramatically improved survival for immunocompetent patients and has become the standard of care for a variety of tumors, including HCC, it is mainly used outside the scope of organ transplantation owing to potentially fatal allograft rejection. Nevertheless, accumulative evidence has expanded the therapeutic paradigms of immunotherapy for HCC, from downstaging or bridging management in the pretransplant setting to the salvage or adjuvant strategy in the posttransplant setting. Generally, immunotherapy mainly includes immune checkpoint inhibitors (ICIs), adoptive cell transfer (ACT) and vaccine therapy. ICIs, followed by ACT, have been most investigated in LT, with some promising results. Because of the complex tumor microenvironment and immunoreactivity when immunosuppressants are combined with immunotherapy, it is difficult to reach formulations for immunosuppressant adjustment and the optimal selection of immunotherapy as well as patients. In addition, the absence of effective biomarkers for identifying rejection and tumor response is still an unresolved barrier to successful clinical immunotherapy applications for LT. In this review, we comprehensively summarize the available evidence of immunotherapy used in LT that is specific to HCC. Moreover, we discuss clinically concerning issues regarding the concurrent goals of graft protection and antitumor response.

Improvement of PD-1 Blockade Efficacy and Elimination of Immune-Related Gastrointestinal Adverse Effect by mTOR Inhibitor

During the past decades, immunotherapy, especially the antibody-mediated immune checkpoint blockade (ICB) has shown durable tumor inhibition and changed the paradigm of cancer treatment. However, a growing body of evidence suggests that ICB treatment induces severe immune-related adverse events (irAEs), and the side effect even leads to the discontinuation of lifesaving treatment. Here, we found that ICB treatment induces colitis in melanoma patients and promotes the infiltration of CD8⁺ effector T cells into colitic lesions. Further transcriptomic dissection indicated the PI3K-AKT-mTOR pathway was highly activated in CD8⁺ effector T cells of colitic lesions. Moreover, we developed a mouse melanoma model to recapitulate the gastrointestinal toxicity of anti-PD-1 treatment in clinical settings. Anti-PD-1 treatment significantly contributed to the infiltration of CD8⁺ T cells, and correspondingly induced severe enteritis. Immunohistochemistry experiments showed that the PI3K-AKT-mTOR pathway of T cells was activated by anti-PD-1 treatment. Blockade of the pathway with mTOR inhibitor sirolimus not only inhibits tumor growth but also suppresses the T cell infiltration in colitic lesions. More importantly, combination with sirolimus and anti-PD-1 synergistically inhibits tumor growth via inducing the immunogenic cell death of tumor cells in vivo. In summary, our research demonstrated the principle of mTOR inhibitor and anti-PD-1 combinatorial therapeutic regimen, which provided a novel therapeutic strategy for irAEs in clinics.

Treatment of Cutaneous Squamous Cell Carcinoma with Immune Checkpoint Inhibitors in Special Populations

Cutaneous squamous cell carcinoma (cSCC) may develop in patients with dysregulated immune activation (pre-existing autoimmune diseases or immunosuppression due to hematopoietic/solid organ transplant recipients), patients with a compromised immune function (long-term immunosuppression), and patients carrying chronic viral infections, or those affected by lymphoproliferative diseases. It should be also considered that patients presenting with immunosuppression have a high incidence of cSCC (65-250-times higher than general population), highlighting the central role played by the immune system in the development of cSCC. All these cases must be considered as "special populations" for treatment with immune checkpoint inhibitors (ICIs), as the safety and activity of these drugs have not been studied on these specific cases, since these patients were excluded from clinical trials leading to approval of ICIs. It is therefore important to gain as much information as possible from the analysis of real-life data, to derive an indication to be adopted in everyday clinical setting. Moreover, therapeutic alternatives other than ICIs are scarce, mainly consisting in chemotherapy and anti-EGFR agents, whose activity is lower than immunotherapy and whose toxicity (particularly with chemotherapy) are not sustainable by this frail population. Here, we describe the current evidence of treatment with ICIs in special populations and conclude that it is necessary to find a balance between treatment risks (toxicities) and benefits (efficacy), as well as engaging a multidisciplinary team of experts to thoroughly manage and treat these patients.

Directing T-Cell Immune Responses for Cancer Vaccination and Immunotherapy

Cancer vaccination and immunotherapy revolutionised the treatment of cancer, a result of decades of research into the immune system in health and disease. However, despite recent breakthroughs in treating otherwise terminal cancer, only a minority of patients respond to cancer immunotherapy and some cancers are largely refractive to immunotherapy treatment. This is due to numerous issues intrinsic to the tumour, its microenvironment, or the immune system. CD4+ and CD8+ αβ T-cells emerged as the primary effector cells of the anti-tumour immune response but their function in cancer patients is often compromised. This review details the mechanisms by which T-cell responses are hindered in the setting of cancer and refractive to immunotherapy, and details many of the approaches under investigation to direct T-cell function and improve the efficacy of cancer vaccination and immunotherapy.

Pan-Cancer Analysis Reveals Alternative Splicing Characteristics Associated With Immune-Related Adverse Events Elicited by Checkpoint Immunotherapy

Immune-related adverse events (irAEs) can impair the effectiveness and safety of immune checkpoint inhibitors (ICIs) and restrict the clinical applications of ICIs in oncology. The predictive biomarkers of irAE are urgently required for early diagnosis and subsequent management. The exact mechanism underlying irAEs remains to be fully elucidated, and the availability of predictive biomarkers is limited. Herein, we performed data mining by combining pharmacovigilance data and pan-cancer transcriptomic information to illustrate the relationships between alternative splicing characteristics and irAE risk of ICIs. Four distinct classes of splicing characteristics considered were associated with splicing factors, neoantigens, splicing isoforms, and splicing levels. Correlation analysis confirmed that expression levels of splicing factors were predictive of irAE risk. Adding DHX16 expression to the bivariate PD-L1 protein expression-fPD1 model markedly enhanced the prediction for irAE. Furthermore, we identified 668 and 1,131 potential predictors based on the correlation of the incidence of irAEs with splicing frequency and isoform expression, respectively. The functional analysis revealed that alternative splicing might contribute to irAE pathogenesis via coordinating innate and adaptive immunity. Remarkably, autoimmune-related genes and autoantigens were preferentially over-represented in these predictors for irAE, suggesting a close link between autoimmunity and irAE occurrence. In addition, we established a trivariate model composed of CDC42EP3-206, TMEM138-211, and IRX3-202, that could better predict the risk of irAE across various cancer types, indicating a potential application as promising biomarkers for irAE. Our study not only highlights the clinical relevance of alternative splicing for irAE development during checkpoint immunotherapy but also sheds new light on the mechanisms underlying irAEs.

The double-edged sword: Harnessing PD-1 blockade in tumor and autoimmunity

[Figure: see text].

Interaction between intestinal microbiota and tumour immunity in the tumour microenvironment

In recent years, an increasing number of studies have reported that intestinal microbiota have an important effect on tumour immunity by affecting the tumour microenvironment (TME). The intestinal microbiota are closely associated with various immune cells, such as T lymphocytes, natural killer cells (NK cells) and macrophages. Some bacteria, such as Akkermansia muciniphila (A. muciniphila) and Lactobacillus reuteri (L. reuteri), have been shown to improve the effect of tumour immunity. Furthermore, microbial imbalance, such as the increased abundance of Fusobacterium nucleatum (F. nucleatum) and Helicobacter hepaticus (H. hepaticus), generally causes tumour formation and progression. In addition, some microbiota also play important roles in tumour immunotherapy, especially PD-L1-related therapies. Therefore, what is the relationship between these processes and how do they affect each other? In this review, we summarize the interactions and corresponding mechanisms among the intestinal microbiota, immune system and TME to facilitate the research and development of new targeted drugs and provide new approaches to tumour therapy.

[The use of immuno-oncologic therapy in hepatocellular carcinoma in the context of liver transplantation. An interdisciplinary benefit/risk assessment]

BACKGROUND

Multiple systemic therapy options have been recently approved for the treatment of hepatocellular carcinoma (HCC). In particular, immuno-oncology combination therapies can now achieve impressive response rates and significantly prolonged survival with good tolerability. These immuno-oncology (IO)-based combinations are currently not only evaluated for the therapy of advanced HCC, but increasingly also in earlier stages in terms of peri-interventional therapy concepts and also for down-sizing to local therapies. In the context of liver transplantation (LTx), a particularly critical benefit/risk assessment must be made before the use of immunotherapeutics in the context of multimodal concepts, since the risk of a potentially lethal rejection can be significantly increased by immunotherapy.

METHODS

This review is based on a selective literature search performed between December 2020 and April 2021 in the PubMed and Cochrane Library databases. Guidelines, expert opinions, and recommendations from professional societies were given special consideration.

RESULTS

Nearly one in five LTx in Germany are performed due to HCCs. In this context, LTx is a curative therapy option not only for the underlying liver disease but also for the malignant tumor. Individual case reports indicate that IO therapy prior to LTx may increase the risk of rejection or liver failure after subsequent liver transplantation. Since 2015, immunotherapeutics have also been widely used for tumor therapy in patients after LTx. In small case series, rejection rates of 36%, associated with rejection-related mortality of 20% of treated patients, have been described. A similar incidence of rejection has also been described following the use of immunotherapeutics in patients after other organ transplantations.

CONCLUSION

In the context of organ transplantation, IO therapy carries the risk of graft rejection, which can lead to graft loss and also patient death. However, from today's point of view, IO-based therapy can be considered in the context of organ transplantation with a careful benefit/risk assessment.

Chemotherapy, targeted therapy and immunotherapy: Which drugs can be safely used in the solid organ transplant recipients?

In solid organ transplant recipients, cancer is associated with worse prognosis than in the general population. Among the causes of increased cancer‐associated mortality, are the limitations in selecting the optimal anticancer regimen in solid organ transplant recipients, because of the associated risks of graft toxicity and rejection, drug‐to‐drug interactions, reduced kidney or liver function, and patient frailty and comorbid conditions. The advent of immunotherapy has generated further challenges, mainly because checkpoint inhibitors increase the risk of rejection, which may have life‐threatening consequences in recipients of life‐saving organs. In general, there are no safe or unsafe anticancer drugs. Rather, the optimal choice of the anticancer regimen results from a careful risk/benefit assessment, from the awareness of potential pharmacokinetic and pharmacodynamic drug‐to‐drug interactions, and of the risk of drug overexposure in patients with kidney or liver dysfunction. In this review, we summarize general principles that may help the oncologists and transplant physicians in the multidisciplinary management of recipients of solid organ transplantation with cancer who are candidates for chemotherapy, targeted therapy, or immunotherapy.

Elevated serum eotaxin and IP-10 levels as potential biomarkers for the detection of esophageal squamous cell carcinoma

Background and Aims

Esophageal squamous cell cancer (ESCC) is one of the leading malignant cancers with a high incidence and mortality. Exploring novel serum biomarkers will help improve the management and monitoring of ESCC.

Methods

In the present study, we first used a ProcartaPlex Array to screen for serum proteins that were increased in 40 ESCC patients compared with matched normal controls; we found that eight proteins (IL‐2, IL‐5, IP‐10, IL‐8, eotaxin, TNF‐α, HGF, and MIP‐1b) had higher serum levels in ESCC patients than in normal controls. We further verified the clinical relevance of the candidate biomarkers with a larger sample of sera.

Results

In the 174 tested ESCC patients and 189 normal controls, the serum levels of eotaxin and IP‐10 were significantly higher in patients than in normal controls (p = 0.0038, 0.0031). In particular, these two proteins were also elevated in the sera of patients with early‐stage (0‐IIA) ESCC (p = 0.0041, 0.0412). When combining CEA and CYFRA21‐1 (in use clinically) with eotaxin or IP‐10, the effectiveness of detecting ESCC was superior to that of CEA and/or CYFRA21‐1 alone. Moreover, the serum level of eotaxin dropped significantly after surgical resection of primary tumors compared with that in preoperative ESCC samples (p < 0.001).

Conclusions

The data suggest that serum eotaxin and IP‐10 might be potential biomarkers for the detection of ESCC.

Mechanisms Driving Immune-Related Adverse Events in Cancer Patients Treated with Immune Checkpoint Inhibitors

PURPOSE OF REVIEW

In the past decade, immune checkpoint inhibitors (ICIs) have revolutionized the field of cancer treatment. With the continuing rise in the number of cancer patients eligible for ICIs, a corresponding rise in immune-related adverse events (irAEs) is occurring. IrAEs are inflammatory reactions against normal, healthy tissue that occur due to ICI-induced activation of the immune system. Although the exact immune pathogenesis driving irAE development remains unknown, we review the main proposed mechanisms, highlighting how they may inform irAE prediction and treatment.

RECENT FINDINGS

IrAEs are common and diverse, varying in incidence, timing, and severity. The possible mechanisms driving irAEs include (1) activation of cytotoxic T cells; (2) activation of B cells and increased autoantibody production; (3) direct molecular mimicry and off-target toxicity; (4) activation of intracellular signaling and pro-inflammatory cytokine production; and (5) environmental modifiers of immune system activation, including composition of the host gut microbiome. These mechanisms may help identify predictive biomarkers and targeted treatment strategies. IrAEs are driven by multiple components of the immune system. More research is needed to understand their immunopathogenesis so that clinicians across all specialties may more effectively monitor and manage these increasingly common conditions.

Immunotherapy use outside clinical trial populations: never say never?

BACKGROUND

Based on favourable outcomes in clinical trials, immune checkpoint inhibitors (ICIs), most notably programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte antigen-4 (CTLA-4) inhibitors, are now widely used across multiple cancer types. However, due to their strict inclusion and exclusion criteria, clinical studies often do not address challenges presented by non-trial populations.

DESIGN

This review summarises available data on the efficacy and safety of ICIs in trial-ineligible patients, including those with autoimmune disease, chronic viral infections, organ transplants, organ dysfunction, poor performance status, and brain metastases, as well as the elderly, children, and those who are pregnant. In addition, we review data concerning other real-world challenges with ICIs, including timing of therapy switch, relationships to radiotherapy or surgery, re-treatment after an immune-related toxicity, vaccinations in patients on ICIs, and current experience around ICI and coronavirus disease-19. Where possible, we provide recommendations to aid the often-difficult decision-making process in those settings.

CONCLUSIONS

Data suggest that ICIs are often active and have an acceptable safety profile in the populations described above, with the exception of PD-1 inhibitors in solid organ transplant recipients. Decisions about whether to treat with ICIs should be personalised and require multidisciplinary input and careful counselling of patients with respect to potential risks and benefits. Clinical judgements need to be carefully weighed, considering factors such as underlying cancer type, feasibility of alternative treatment options, or activity in trial-eligible patients.

Application of Immune Checkpoint Inhibitors in Solid Organ Transplantation Recipients: A Systematic Review

BACKGROUND

Solid organ transplantation (SOT) is a treatment method for end-stage organ diseases and improve their life quality, while using long-term immunosuppressant drugs (ISD) is needed to suppress the function of the immune system. Immune checkpoint inhibitors (ICIs) are a class of anti-tumor drugs that kill tumors by activating the autoimmune system. The primary objective of our systematic review is to investigate the risk factors for organ rejection and the efficacy of ICIs in solid organ transplantation recipients (SOTRs).

METHODS

We searched four databases to find relevant articles up to January 2021. A total of 61 articles involving 106 SOTRs met the screening criteria and were included in our systematic review. The collected data were statistical described, and the risk factors were analyzed by logistic regression.

RESULTS

Forty-four patients (41.5%) developed host-versus-graft response (HVGR) after ICIs. mTOR inhibitors (pre-ICIs) (p = 0.069, OR = 0.377, 95% CI 0.132-1.078) and calcineurin inhibitors (post-ICIs) (p = 0.056, OR = 0.375, 95%CI 0.137-1.025) may help reduce the incidence of HVGR. Hormones (pre-ICIs) (p = 0.026, OR = 3.150, 95%CI 1.150-8.628) and anti-metabolites (pre-ICIs) (p = 0.022, OR = 3.214, 95%CI 1.185-8.720) may adversely affect the efficacy of ICIs. Only 35.6% of patients both responded well to ICIs treatment and did not develop HVGR.

CONCLUSIONS

Our systematic review summarizes the use of ICIs in SOTRs and evaluates the efficacy of ICIs and the risk factors that induce HVGR. Through risk factor analysis, we found that mTOR inhibitors and calcineurin inhibitors may help to reduce the occurrence of HVGR; hormones and anti-metabolic drugs may have adverse effects on the efficacy of ICIs. In addition, there is a contradictory relationship between the occurrence of HVGR and the efficacy of ICIs.

Integrated transcriptional-phenotypic analysis captures systemic immunomodulation following antiangiogenic therapy in renal cell carcinoma patients

BACKGROUND

The combination of immune checkpoint blockade (ICB) with standard therapies is becoming a common approach for overcoming resistance to cancer immunotherapy in most human malignancies including metastatic renal cell carcinoma (mRCC). In this regard, insights into the immunomodulatory properties of antiangiogenic agents may help designing multidrug schedules based on specific immune synergisms.

METHODS

We used orthogonal transcriptomic and phenotyping platforms combined with functional analytic pipelines to elucidate the immunomodulatory effect of the antiangiogenic agent pazopanib in mRCC patients. Nine patients were studied longitudinally over a period of 6 months. We also analyzed transcriptional data from The Cancer Genome Atlas (TCGA) RCC cohort (N = 571) to assess the prognostic implications of our findings. The effect of pazopanib was assessed in vitro on NK cells and T cells. Additionally, myeloid-derived suppressor (MDSC)-like cells were generated from CD14+ monocytes transfected with mimics of miRNAs associated with MDSC function in the presence or absence of pazopanib.

RESULTS

Pazopanib administration caused a rapid and dramatic reshaping in terms of frequency and transcriptional activity of multiple blood immune cell subsets, with a downsizing of MDSC and regulatory T cells in favor of a strong enhancement in PD-1 expressing cytotoxic T and Natural Killer effectors. These changes were paired with an increase of the expression of transcripts reflecting activation of immune-effector functions. This immunomodulation was marked but transient, peaking at the third month of treatment. Moreover, the intratumoral expression level of a MDSC signature (MDSC INT) was strongly associated with poor prognosis in RCC patients. In vitro experiments indicate that the observed immunomodulation might be due to an inhibitory effect on MDSC-mediated suppression, rather than a direct effect on NK and T cells.

CONCLUSIONS

The marked but transient nature of this immunomodulation, peaking at the third month of treatment, provides the rationale for the use of antiangiogenics as a preconditioning strategy to improve the efficacy of ICB.

Treatment outcomes of molecular targeted therapy following nivolumab in metastatic renal cell carcinoma

OBJECTIVE

The purpose of this study was to assess the therapeutic efficacy of molecular targeted therapies following nivolumab in metastatic renal cell carcinoma and to examine the relationship between therapeutic efficacy and the specific molecular targeted therapy used.

METHODS

We retrospectively reviewed the medical records of 115 metastatic renal cell carcinoma patients who were treated with nivolumab at our institution and five affiliated hospitals. Among them, 52 patients who received subsequent molecular targeted therapy following nivolumab were selected to survey treatment outcomes. Progression-free survival and overall survival were estimated with Kaplan-Meier curves, and differences were analyzed by the log-rank test.

RESULTS

Among the 52 eligible patients, 40 (76.9%) were treated with tyrosine kinase inhibitors and 12 (23.1%) were treated with mammalian target of rapamycin inhibitor. The median time to treatment failure and progression-free survival of subsequent molecular targeted therapy were 5.6 and 8.0 months, respectively. The median overall survival from the initiation of first-line therapy was not reached. The disease control rate of subsequent molecular targeted therapy was 69.2% (partial response: 25.0%, stable disease: 44.2%). The median progression-free survival of subsequent tyrosine kinase inhibitor and mammalian target of rapamycin inhibitor were 9.2 and 8.0 months, respectively (P = 0.37). The progression-free survival of patients whose best response to prior nivolumab was either progressive disease or stable disease/partial response were 6.3 and 11.3 months, respectively (P = 0.36).

CONCLUSIONS

Molecular targeted therapies following nivolumab had comparatively better therapeutic efficacy, which was confirmed regardless of the type of molecular targeted agent used.