PD-L1 and PD-L2 Genetic Alterations Define Classical Hodgkin Lymphoma and Predict Outcome

Classic Hodgkin Lymphoma in Adolescents and Young Adults

Hodgkin lymphoma (HL) represents one of the more common cancers occurring in adolescent and young adults (AYAs) age 15-39 years. Despite a generally high cure rate, age-related differences in HL biology and the optimal therapeutic approaches including supportive care and risks for long-term adverse effects in the AYA population remain understudied. After an overview of HL epidemiology and biology in the AYA population, this review will cover frontline pediatric and adult treatment approaches. Recently completed and ongoing studies will foster harmonization of risk group definition and trial eligibility criteria across the AYA spectrum, enabling more rapid progress. In addition to treatment approaches, an evolving holistic care approach to AYA HL will result in enhanced understanding of unique challenges, and continued improved short- and long-term outcome for these patients.

Diagnostic, Pathologic, and Therapeutic Considerations for Primary CNS Lymphoma

Primary CNS lymphoma (PCNSL) is a rare lymphoma representing 3% of CNS malignancies. The diagnosis is complicated by the unique risks associated with brain biopsy, and the treatment is similarly complicated by the restriction of effective therapeutics able to cross the blood-brain barrier. Currently, the majority of individuals diagnosed with this disease are immunocompetent although immune deficiency related to HIV or immunosuppressive therapy remains an important risk factor. Improvements in both frontline therapy and consolidation options, including the use of hematopoietic stem-cell transplantation, have translated to improved survival. Unfortunately, patients experiencing relapsed or refractory disease often fare poorly. Here, we review key clinical, pathologic, and therapeutic aspects of PCNSL and highlight challenging clinical scenarios that may be encountered by the treating oncologist.

Comparison of genomic alterations in Epstein-Barr virus-positive and Epstein-Barr virus-negative diffuse large B-cell lymphoma

BACKGROUND

Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphoma (EBV-posDLBCL) is an aggressive B-cell lymphoma that often presents similar morphological and immune phenotype features to that of EBV-negative DLBCL (EBV-negDLBCL).

AIMS AND METHODS

To better understand their difference in genomic landscape, we performed whole-exome sequencing (WES) of EBV-posDLBCL and EBV-negDLBCL.

RESULTS

This analysis revealed a new mutational signature 17 (unknown) and signature 29 (smoking) in EBV-posDLBCL as well as a specific mutational signature 24 (associated with aflatoxin) in EBV-negDLBCL. Compared with EBV-negDLBCL, more somatic copy number alterations (CNAs) and deletions were detected in EBV-posDLBCL (p = 0.01). The most frequent CNAs specifically detected in EBV-posDLBCL were gains at 9p24.1 (PDL1 and JAK2), 8q22.2-q24.23 (DEPTOR and MYC), and 7q31.31-q32.2 (MET), which were validated in additional EBV-posDLBCL cases. Overall, 53.7% (22/41) and 62.9% (22/35) of the cases expressed PD-L1 and c-MET, respectively, in neoplastic cells, whereas only 15.4% (4/26) expressed c-MYC. Neoplastic c-MET expression was positively correlated with PD-L1 (p < 0.001) and MYC expression (p = 0.016). However, EBV-posDLBCL cases did not show any differences in overall survival between PD-L1-, c-MET-, or c-MYC-positive and -negative cases or between age-related groups. Analysis of the association between somatic mutation load and EBV status showed no difference in the distribution of tumor mutant burden between the two lymphomas (p = 0.41). Recurrent mutations in EBV-posDLBCL implicated several genes, including DCAF8L1, KLF2, and NOL9, while in EBV-negDLBCL, ANK2, BPTF, and CNIH3 were more frequently mutated. Additionally, PIM1 is the most altered gene in all the WES-detected cases.

CONCLUSIONS

Our results confirm that genomic alteration differs significantly between EBV-posDLBCL and EBV-negDLBCL, and reveal new genetic alterations in EBV-posDLBCL. The positive correlation of c-MET and PD-L1/c-Myc expression may be involved in the pathogenesis of EBV-posDLBCL, which is should be explored prospectively in trials involving MET-directed therapies.

Results from a phase I trial of pembrolizumab plus vorinostat in relapsed/refractory B-cell non-Hodgkin lymphoma

Outcomes after programmed death-1 (PD-1) blockade in B-cell lymphomas are disappointing with few durable responses. Histone deacetylase inhibitors exhibit favorable immunomodulatory effects and demonstrate synergistic anti-tumor immune responses with anti-PD-1 therapy in preclinical models. We, therefore, developed a phase I study to evaluate the safety and preliminary efficacy of pembrolizumab with vorinostat in relapsed/refractory B-cell lymphomas. Patients were treated in a dose-escalation cohort using a Rolling 6 design followed by an expansion cohort at the recommended phase II dose (R2PD). Fifty-two patients were enrolled (32 Hodgkin and 20 non-Hodgkin lymphoma [NHL]). Here, we report safety data from the dose escalation cohort, and the toxicity and efficacy within NHL patients. Vorinostat was administered twice daily on days 1-5 and 8-12 (dose-level [DL]1: 100 mg; DL2: 200 mg) and pembrolizumab (200 mg) was administered on day 1 of each 3-week cycle. Of six patients treated at DL1, one had a dose-limiting toxicity (DLT) (Stevens-Johnson syndrome [SJS]), and one of six had a DLT at DL2 (thromboembolism); therefore, DL2 was the RP2D. The patient developing SJS was treated with corticosteroids, infliximab, and cyclosporine but ultimately died of invasive fungal infection from the extensive immunosuppression used to treat the SJS. The most common adverse events were hypertension, diarrhea, and cytopenias. Of 20 NHL patients, nine had follicular lymphoma (FL) and 11 had diffuse large B-cell lymphoma (DLBCL). Five DLBCL patients had primary mediastinal B-cell lymphoma (PMBL). The complete and overall response rates (CR and ORR) were 11% and 22% for FL and 45% and 55% for all DLBCL. Amongst DLBCL, the CR and ORR was 80% and 80% for PMBL and 17% and 33% for non-PMBL. In conclusion, pembrolizumab with vorinostat was tolerable and produced responses in relapsed/refractory B-cell NHL, with particularly notable efficacy in PMBL (clinicaltrials gov. Identifier: NCT03150329).

Efficacy and Safety of Immune Checkpoint Inhibitors in Hematologic Malignancies

The emergence of immune checkpoint inhibitors (ICIs) has led to a dramatic paradigm shift within the landscape of cancer treatment, igniting significant interest in their potential application in treating hematologic malignancies. This comprehensive review critically has examined the existing body of literature to shed light on the evolving understanding of the efficacy and safety of ICIs, both as a single agent and in combination regimens in hematologic malignancies. Across distinct lymphoma subtypes, the observed treatment responses exhibit diversity, and conflicts. Notably, Hodgkin lymphoma and certain non-Hodgkin lymphomas such as primary mediastinal B-cell lymphoma, emerge as remarkable cases, showing encouraging response rates and outcomes. However, the efficacy of ICIs reveals variations among subtypes such as chronic lymphocytic leukemia and multiple myeloma. Combination therapies consistently demonstrated superior outcomes compared to monotherapy in several malignancies. While the potential benefits of ICIs in hematologic malignancies are evident, the safety profile warrants careful consideration. Immune-related and other adverse events, though generally tolerable and manageable, highlight the necessity of meticulous monitoring and appropriate intervention. The discussions prompted by these findings underscore the need for tailored treatment approaches, driven by disease subtype, patient characteristics, and potential biomarkers. Moreover, the emerging realm of combination therapies involving immune checkpoint inhibitors holds promise for enhanced treatment outcomes, and ongoing research endeavors aim to unravel the optimal strategies.

Establishment of immune suppression by cancer cells in the tumor microenvironment

With the clinical success of immune checkpoint inhibitors (ICIs), cancer immunotherapy has become an important pillar of cancer treatment in various types of cancer. However, more than half of patients fail to respond to ICIs, even in combination, uncovering a limited window of clinical responses. Therefore, it is essential to develop more effective cancer immunotherapies and to define biomarkers for stratifying responders and nonresponders by exploring the immunological landscape in the tumor microenvironment (TME). It has become clear that differences in immune responses in the TME determine the clinical efficacy of cancer immunotherapies. Additionally, gene alterations in cancer cells contribute to the development of the immunological landscape, particularly immune suppression in the TME. Therefore, integrated analyses of immunological and genomic assays are key for understanding diverse immune suppressive mechanisms in the TME. Developing novel strategies to control immune suppression in the TME from the perspective of immunology and the cancer genome is crucial for effective cancer immunotherapy (immune-genome precision medicine).

The expression mechanism of programmed cell death 1 ligand 1 and its role in immunomodulatory ability of mesenchymal stem cells

Programmed cell death 1 ligand 1 (PD-L1) is an important immunosuppressive molecule, which inhibits the function of T cells and other immune cells by binding to the receptor programmed cell death-1. The PD-L1 expression disorder plays an important role in the occurrence, development, and treatment of sepsis or other inflammatory diseases, and has become an important target for the treatment of these diseases. Mesenchymal stem cells (MSCs) are a kind of pluripotent stem cells with multiple differentiation potential. In recent years, MSCs have been found to have a strong immunosuppressive ability and are used to treat various inflammatory insults caused by hyperimmune diseases. Moreover, PD-L1 is deeply involved in the immunosuppressive events of MSCs and plays an important role in the treatment of various diseases. In this review, we will summarize the main regulatory mechanism of PD-L1 expression, and discuss various biological functions of PD-L1 in the immune regulation of MSCs.

CAR-T Cell Therapy for Classical Hodgkin Lymphoma

Classical Hodgkin lymphoma (cHL) is a malignancy characterized by the presence of Hodgkin and Reed-Sternberg (HRS) cells within a complex tumor microenvironment (TME). Despite advances in conventional therapies, a subset of cHL patients experience relapse or refractory disease, necessitating the exploration of novel treatment strategies. Chimeric antigen receptor T cell (CAR-T cell) therapy has emerged as a promising approach for the management of cHL, harnessing the power of genetically modified T cells to recognize and eliminate tumor cells. In this article, we provide an overview of the pathogenesis of cHL, highlighting the key molecular and cellular mechanisms involved. Additionally, we discuss the rationale for the development of CAR-T cell therapy in cHL, focusing on the identification of suitable targets on HRS cells (such as CD30, CD123, LMP1, and LMP2A), clonotypic lymphoma initiating B cells (CD19, CD20), and cells within the TME (CD123, CD19, CD20) for CAR-T cell design. Furthermore, we explore various strategies employed to enhance the efficacy and safety of CAR-T cell therapies in the treatment of cHL. Finally, we present an overview of the results obtained from clinical trials evaluating the efficacy of CAR-T cell therapies in cHL, highlighting their potential as a promising therapeutic option. Collectively, this article provides a comprehensive review of the current understanding of cHL pathogenesis and the rationale for CAR-T cell therapy development, offering insights into the future directions of this rapidly evolving field.

Biomarkers and experimental models for cancer immunology investigation

The rapid advancement of tumor immunotherapies poses challenges for the tools used in cancer immunology research, highlighting the need for highly effective biomarkers and reproducible experimental models. Current immunotherapy biomarkers encompass surface protein markers such as PD-L1, genetic features such as microsatellite instability, tumor-infiltrating lymphocytes, and biomarkers in liquid biopsy such as circulating tumor DNAs. Experimental models, ranging from 3D in vitro cultures (spheroids, submerged models, air-liquid interface models, organ-on-a-chips) to advanced 3D bioprinting techniques, have emerged as valuable platforms for cancer immunology investigations and immunotherapy biomarker research. By preserving native immune components or coculturing with exogenous immune cells, these models replicate the tumor microenvironment in vitro. Animal models like syngeneic models, genetically engineered models, and patient-derived xenografts provide opportunities to study in vivo tumor-immune interactions. Humanized animal models further enable the simulation of the human-specific tumor microenvironment. Here, we provide a comprehensive overview of the advantages, limitations, and prospects of different biomarkers and experimental models, specifically focusing on the role of biomarkers in predicting immunotherapy outcomes and the ability of experimental models to replicate the tumor microenvironment. By integrating cutting-edge biomarkers and experimental models, this review serves as a valuable resource for accessing the forefront of cancer immunology investigation.

Hodgkin Lymphoma: A disease shaped by the tumor micro- and macroenvironment

The tumor microenvironment (TMicroE) and tumor macroenvironment (TMacroE) are defining features of classical Hodgkin lymphoma (cHL). They are of critical importance to clinicians since they explain the common signs and symptoms, allow us to classify these neoplasms, develop prognostic and predictive biomarkers, bioimaging and novel treatments. The TMicroE is defined by effects of cancer cells to their immediate surrounding and within the tumor. Effects of cancer cells at a distance or outside of the tumor define the TMacroE. Paraneoplastic syndromes are signs and symptoms due to effects of cancer at a distance or the TMacroE, which are not due to direct cancer cell infiltration. The most common paraneoplastic symptoms are B-symptoms, which manifest as fevers, chills, drenching night sweats, and/or weight loss. Less common paraneoplastic syndromes include those that affect the central nervous system, skin, kidney, and hematological autoimmune phenomena including hemophagocytic lymphohistiocytosis (HLH). Paraneoplastic signs such as leukocytosis, lymphopenia, anemia, and hypoalbuminemia are prognostic biomarkers. The neoplastic cells in cHL are the Hodgkin and Reed Sternberg (HRS) cells, which are preapoptotic germinal center B cells with a high mutational burden and almost universal genetic alterations at the 9p24.1 locus primarily through copy gain and amplification with strong activation of signaling via PD-L1, JAK-STAT, NFkB, and c-MYC. In the majority of cases of cHL over 95% of the tumor cells are non-neoplastic. In the TMicroE, HRS cells recruit and mold non-neoplastic cells vigorously via extracellular vesicles, chemokines, cytokines and growth factors such as CCL5, CCL17, IL6, and TGF-β to promote a feed-forward inflammatory loop, which drives cancer aggressiveness and anti-cancer immune evasion. Novel single cell profiling techniques provide critical information on the role in cHL of monocytes-macrophages, neutrophils, T helper, Tregs, cytotoxic CD8+ T cells, eosinophils, mast cells and fibroblasts. Here, we summarize the effects of EBV on the TMicroE and TMacroE. In addition, how the metabolism of the TMicroE of cHL affects bioimaging and contributes to cancer aggressiveness is reviewed. Finally, we discuss how the TMicroE is being leveraged for risk adapted treatment strategies based on bioimaging results and novel immune therapies. In sum, it is clear that we cannot effectively manage patients with cHL without understanding the TMicroE and TMacroE and its clinical importance is expected to continue to grow rapidly.

Hodgkin lymphoma: Focus on evolving treatment paradigms

Hodgkin lymphoma (HL) is a highly curable B-cell malignancy of germinal center origin. Biologically it is a hematologic malignancy that is highly dependent on the immune microenvironment and utilizes immune escape through upregulation of the programmed-death ligands on the neoplastic cells. Despite being highly curable, consensus is lacking nationally and internationally about the optimal approach to management, particularly in limited-stage disease. The addition of brentuximab vedotin and checkpoint inhibitors for the management of HL has led to a rapidly changing treatment landscape. Further studies should be done to include these novel agents at all stages of disease to determine improvements in frontline cure rates and long-term toxicity.

Killer instincts: natural killer cells as multifactorial cancer immunotherapy

Natural killer (NK) cells integrate heterogeneous signals for activation and inhibition using germline-encoded receptors. These receptors are stochastically co-expressed, and their concurrent engagement and signaling can adjust the sensitivity of individual cells to putative targets. Against cancers, which mutate and evolve under therapeutic and immunologic pressure, the diversity for recognition provided by NK cells may be key to comprehensive cancer control. NK cells are already being trialled as adoptive cell therapy and targets for immunotherapeutic agents. However, strategies to leverage their naturally occurring diversity and agility have not yet been developed. In this review, we discuss the receptors and signaling pathways through which signals for activation or inhibition are generated in NK cells, focusing on their roles in cancer and potential as targets for immunotherapies. Finally, we consider the impacts of receptor co-expression and the potential to engage multiple pathways of NK cell reactivity to maximize the scope and strength of antitumor activities.

Clinical PD-1/PD-L1 Blockades in Combination Therapies for Lymphomas

Immunotherapy with the programmed cell death protein 1 (PD-1)/PD-1 ligand (PD-L1) blockade has revolutionized the treatment of advanced solid cancers. However, these clinical benefits have been limited to cases of malignant lymphomas, showing promising results for only classic Hodgkin lymphoma (cHL) and primary mediastinal B-cell lymphoma (PMBCL). To bring clinical benefits to more patients with lymphoma, numerous combination therapies involving PD-1/PD-L1 blockade have been tested in clinical trials in both frontline and relapsed/refractory settings. This article reviews the current landscape of combination therapies with PD-1/PD-L1 blockade for lymphoma and discusses the potential therapeutic approaches. An interim analysis of a phase 3 study demonstrated increased progression-free survival with nivolumab combination therapy over the current frontline treatment in patients with advanced-stage cHL. The results of combination therapies for aggressive B-cell lymphomas, except for PMBCL, have been disappointing. Several clinical trials of combined PD-1/PD-L1 blockade and Bruton's tyrosine kinase inhibitors are exploring its efficacy in patients with chronic lymphocytic leukemia (CLL) with Richter transformation. Several T-cell lymphoma subtypes respond to PD-1/PD-L1 blockade monotherapy. Further clinical trials are underway to investigate appropriate combination regimens with PD-1/PD-L1 blockade, especially for cHL, CLL with Richter transformation, and T-cell lymphoma, in both frontline and relapsed/refractory settings.

Antagonism of androgen receptor signaling by aloe-emodin

Over the past decades, androgen receptor (AR) signaling has been a key driver of both primary and recurrent prostate cancer. In this work, aloe-emodin was identified as a novel AR antagonist, effectively inhibiting AR signaling. Firstly, aloe-emodin can inhibit LNCaP cell growth by promoting apoptosis. Then, the results of Western blot and quantitative real-time PCR further confirmed that aloe-emodin modulated AR protein levels by promoting AR proteasomal degradation, and also inhibited the transcription of the AR downstream target genes, including PSA, KLK2, and TMPRSS2. Furthermore, the result of immunofluorescence showed that aloe-emodin prevented the nuclear translocation of AR. Molecular docking and molecular dynamics simulation suggested that aloe-emodin combined with AR to form stable complexes, which might explain that aloe-emodin prevented the translocation of AR from the cytoplasm to the nucleus by affecting the ligand binding of AR. Therefore, aloe-emodin as a novel AR antagonist may play a crucial role in promoting cancer prevention or complementing pharmacological therapies in the treatment of prostate cancer.

Classic Hodgkin lymphoma in young people

Classic Hodgkin lymphoma (CHL) is a unique form of lymphoid cancer featuring a heterogeneous tumor microenvironment and a relative paucity of malignant Hodgkin and Reed-Sternberg (HRS) cells with characteristic phenotype. Younger individuals (children, adolescents and young adults) are affected as often as the elderly, producing a peculiar bimodal age-incidence profile that has generated immense interest in this disease and its origins. Decades of epidemiological investigations have documented the populations most susceptible and identified multiple risk factors that can be broadly categorized as either biological or environmental in nature. Most risk factors result in overt immunodeficiency or confer more subtle alterations to baseline health, physiology or immune function. Epstein Barr virus, however, is both a risk factor and well-established driver of lymphomagenesis in a significant subset of cases. Epigenetic changes, along with the accumulation of somatic driver mutations and cytogenetic abnormalities are required for the malignant transformation of germinal center-experienced HRS cell precursors. Chromosomal instability and the influence of endogenous mutational processes are critical in this regard, by impacting genes involved in key signaling pathways that promote the survival and proliferation of HRS cells and their escape from immune destruction. Here we review the principal features, known risk factors and lymphomagenic mechanisms relevant to newly diagnosed CHL, with an emphasis on those most applicable to young people.

Scientific techniques in adolescent and young adult classic Hodgkin lymphoma

Understanding the tumor microenvironment and genomic landscape is crucial for better prediction of treatment outcomes and developing novel therapies in Hodgkin lymphoma (HL). Recent advancements in genomics have enabled researchers to gain deeper insights into the genomic characteristics of HL at both single-cell resolution and the whole genome level. The use of noninvasive methods such as liquid biopsies and formalin-fixed paraffin-embedded-based imaging techniques has expanded the possibilities of applying cutting-edge analyses to routine clinically available samples. Collaborative efforts between adult and pediatric group are imperative to translate novel findings into routine patient care.

Prognostic Markers within the Tumour Microenvironment in Classical Hodgkin Lymphoma

Classical Hodgkin lymphoma (cHL) accounts for 0.4% of all new cancer cases globally. Despite high cure rates with standard treatment, approximately 15% of patients still experience relapsed or refractory (RR) disease, and many of these eventually die from lymphoma-related causes. Exciting new targeted agents such as anti-PD-1 agents and brentuximab vedotin have changed the therapeutic paradigm beyond chemotherapy and radiotherapy alone. Advances in understanding of the molecular biology are providing insights in the context of novel therapies. The signature histology of cHL requires the presence of scant malignant Hodgkin Reed-Sternberg cells (HRSCs) surrounded by a complex immune-rich tumour microenvironment (TME). The TME cellular composition strongly influences outcomes, yet knowledge of the precise characteristics of TME cells and their interactions with HRSCs is evolving. Novel high-throughput technologies and single-cell sequencing allow deeper analyses of the TME and mechanisms elicited by HRSCs to propagate growth and avoid immune response. In this review, we explore the evolution of knowledge on the prognostic role of immune cells within the TME and provide an up-to-date overview of emerging prognostic data on cHL from new technologies that are starting to unwind the complexity of the cHL TME and provide translational insights into how to improve therapy in the clinic.

Insights from a 30-year journey: function, regulation and therapeutic modulation of PD1

PD1 was originally discovered in 1992 as a molecule associated with activation-induced cell death in T cells. Over the past 30 years, it was found that PD1 has a critical role in avoiding overactivation-induced cell death and autoimmunity, whereas its inhibition unleashes anticancer immunity. Here, we outline the journey from the discovery of PD1 to its role as a breakthrough target in cancer immunotherapy. We describe its regulation and function and examine how a mechanistic understanding of PD1 signalling suggests a central function in setting the T cell activation threshold, thereby controlling T cell proliferation, differentiation, exhaustion and metabolic status. This threshold theory, in combination with new insights into T cell metabolism and a better understanding of immune cell modulation by the microbiota, can provide guidance for the development of efficient combination therapies. Moreover, we discuss the mechanisms underlying immune-related adverse events after PD1-targeted therapy and their possible treatment.

SOHO State of the Art Updates and Next Questions | From Biology to Therapy: Progress in Hodgkin Lymphoma

Classic Hodgkin lymphoma (HL) is a unique lymphoid malignancy where the malignant cells comprise only 1% to 2% of the total tumor cellularity. Over the past 2 decades, the treatment of HL has evolved drastically based on the advent of novel targeted therapies. Novel agents including programmed death-1 (PD-1) inhibitors, antibody-drug conjugates such as brentuximab vedotin, bispecific antibodies, and chimeric antigen receptor (CAR) T cell therapies have served to shape the management of HL in the frontline as well as the relapsed and refractory (R/R) setting. Some of these agents have been incorporated into treatment algorithms, while others are currently under investigation demonstrating promising results. This review focuses on highlighting the underlying tumor biology forming the basis of therapeutics in HL, and reviews some of the emerging and established novel therapies.

AURKA inhibitor-induced PD-L1 upregulation impairs antitumor immune responses

Introduction

Tumor immunotherapy targeting PD-L1 has emerged as one of the powerful tools for tumor therapy. Numerous studies indicate that tumor-targeted drugs critically have an influence on the interaction between the immune system and tumors by changing the expression of PD-L1, which is beneficial for immunotherapy. Our study provided novel evidence for improving the drug regimen in tumor targeted therapy and immunotherapy.

Methods

The expression of PD-L1 on SKBR3, MDA-MB-231, MCF7, 4T1, MC38 and B16 cells was evaluated by flow cytometry after treatment with six preclinical targeted drugs (ARN-509, AZD3514, Galeterone, Neratinib, MLN8237 and LGK974). AURKA was knockdowned by using the specific siRNA or CRISPR-Cas9 technology. In the 4T1-breast tumor and colorectal cancer xenograft tumor models, we determined the number of infiltrated CD3+ and CD8+ T cells in tumor tissues by IHC.

Results

We found that AURKA inhibitor MLN8237 promoted the expression of PD-L1 in a time- and concentration-dependent manner while exerted its antitumor effect. Knockdown of AURKA could induce the upregulation of PD-L1 on SKBR3 cells. MLN8237-induced PD-L1 upregulation was mainly associated with the phosphorylation of STAT3. In the 4T1-breast tumor xenograft model, the infiltrated CD3+ and CD8+ T cells decreased after treatment with MLN8237. When treated with MLN8237 in combination with anti-PD-L1 antibody, the volumes of tumor were significantly reduced and accompanied by increasing the infiltration of CD3+ and CD8+ T cells in colorectal cancer xenograft tumor model.

Discussion

Our data demonstrated that MLN8237 improved the effect of immunology-related therapy on tumor cells by interacting with anti-PD-L1 antibody, which contributed to producing creative sparks for exploring the possible solutions to overcoming drug resistance to tumor targeted therapy.

Optimizing Treatment for Relapsed/Refractory Classic Hodgkin Lymphoma in the Era of Immunotherapy

Most patients with classic Hodgkin lymphoma (cHL) are cured with combination chemotherapy, but approximately 10-20% will relapse, and another 5-10% will have primary refractory disease. The treatment landscape of relapsed/refractory (R/R) cHL has evolved significantly over the past decade following the approval of brentuximab vedotin (BV), an anti-CD30 antibody-drug conjugate, and the PD-1 inhibitors nivolumab and pembrolizumab. These agents have significantly expanded options for salvage therapy prior to autologous hematopoietic cell transplantation (AHCT), post-transplant maintenance, and treatment of relapse after AHCT, which have led to improved survival in the modern era. In this review, we highlight our approach to the management of R/R cHL in 2023 with a focus on choosing first salvage therapy, post-transplant maintenance, and treatment of relapse after AHCT. We also discuss the management of older adults and transplant-ineligible patients, who require a separate approach. Finally, we review novel immunotherapy approaches in clinical trials, including combinations of PD-1 inhibitors with other immune-activating agents as well as novel antibody-drug conjugates, bispecific antibodies, and cellular immunotherapies. Ongoing studies assessing biomarkers of response to immunotherapy and dynamic biomarkers such as circulating tumor DNA may further inform treatment decisions and enable a more personalized approach in the future.

The role of tumor immune microenvironment in chordoma: promising immunotherapy strategies

Chordoma is a rare malignant bone tumor with limited therapeutic options, which is resistant to conventional chemotherapy and radiotherapy, and targeted therapy is also shown with little efficacy. The long-standing delay in researching its mechanisms of occurrence and development has resulted in the dilemma of no effective treatment targets and no available drugs in clinical practice. In recent years, the role of the tumor immune microenvironment in driving tumor growth has become a hot and challenging topic in the field of cancer research. Immunotherapy has shown promising results in the treatment of various tumors. However, the study of the immune microenvironment of chordoma is still in its infancy. In this review, we aim to present a comprehensive reveal of previous exploration on the chordoma immune microenvironment and propose promising immunotherapy strategies for chordoma based on these characteristics.

Epigenetic Regulation of the Expression of T Cell Stimulatory and Inhibitory Factors by Histone H3 Lysine Modification Enzymes and Its Prognostic Roles in Glioblastoma

BACKGROUND

This study aimed to identify the specific T cell co-stimulatory and co-inhibitory factors that play prognostic roles in patients with glioblastoma. Additionally, the unique histone H3 modification enzymes that regulate the expression levels of these specific co-stimulatory and co-inhibitory factors were investigated.

METHODS

The medical records of 84 patients newly diagnosed with glioblastoma at our institution from January 2006 to December 2020 were retrospectively reviewed. Immunohistochemical (IHC) staining for T cell co-stimulatory factors (CD27, CD28, CD137, OX40, and ICOS), T cell co-inhibitory factors (CTLA4, PD1, PD-L1, TIM3, and CD200R), and histone H3 lysine modification enzymes (MLL4, RIZ, EZH1, NSD2, KDM5c, JMJD1a, UTX, and JMJD5) was performed on archived paraffin-embedded tissues obtained by biopsy or resection. Quantitative real time-polymerase chain reaction (qRT-PCR) was performed for specific factors, which demonstrated causal relationships, in order to validate the findings of the IHC examinations.

RESULTS

The mean follow-up duration was 27.5 months (range, 4.1-43.5 months). During this period, 76 patients (90.5%) died, and the mean OS was 19.4 months (95% confidence interval, 16.3-20.9 months). Linear positive correlations were observed between the expression levels of CD28 and JMJD1a (R2 linear = 0.982) and those of CD137 and UTX (R2 linear = 1.528). Alternatively, significant negative correlations were observed between the expression levels of CTLA4 and RIZ (R2 linear = -1.746) and those of PD-L1 and EZH1 (R2 linear = -2.118); these relationships were confirmed by qRT-PCR. In the multivariate analysis, increased expression levels of CD28 (P = 0.042), and CD137 (P = 0.009), and decreased expression levels of CTLA4 (P = 0.003), PD-L1 (P = 0.020), and EZH1 (P = 0.040) were significantly associated with longer survival.

CONCLUSION

These findings suggest that the expression of certain T cell co-stimulatory factors, such as CD28 and CD 137, and co-inhibitory factors, such as CTLA4 and PD-L1 are associated with prognosis of glioblastoma patients.

Immunotherapy in hematologic malignancies: achievements, challenges and future prospects

The immune-cell origin of hematologic malignancies provides a unique avenue for the understanding of both the mechanisms of immune responsiveness and immune escape, which has accelerated the progress of immunotherapy. Several categories of immunotherapies have been developed and are being further evaluated in clinical trials for the treatment of blood cancers, including stem cell transplantation, immune checkpoint inhibitors, antigen-targeted antibodies, antibody-drug conjugates, tumor vaccines, and adoptive cell therapies. These immunotherapies have shown the potential to induce long-term remission in refractory or relapsed patients and have led to a paradigm shift in cancer treatment with great clinical success. Different immunotherapeutic approaches have their advantages but also shortcomings that need to be addressed. To provide clinicians with timely information on these revolutionary therapeutic approaches, the comprehensive review provides historical perspectives on the applications and clinical considerations of the immunotherapy. Here, we first outline the recent advances that have been made in the understanding of the various categories of immunotherapies in the treatment of hematologic malignancies. We further discuss the specific mechanisms of action, summarize the clinical trials and outcomes of immunotherapies in hematologic malignancies, as well as the adverse effects and toxicity management and then provide novel insights into challenges and future directions.

The progress of novel strategies on immune-based therapy in relapsed or refractory diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL) can be cured with standard front-line immunochemotherapy, whereas nearly 30-40% of patients experience refractory or relapse. For several decades, the standard treatment strategy for fit relapsed/refractory (R/R) DLBCL patients has been high-dose chemotherapy followed by autologous hematopoietic stem cell transplant (auto-SCT). However, the patients who failed in salvage treatment or those ineligible for subsequent auto-SCT have dismal outcomes. Several immune-based therapies have been developed, including monoclonal antibodies, antibody-drug conjugates, bispecific T-cell engaging antibodies, chimeric antigen receptor T-cells, immune checkpoint inhibitors, and novel small molecules. Meanwhile, allogeneic SCT and radiotherapy are still necessary for disease control for fit patients with certain conditions. In this review, to expand clinical treatment options, we summarize the recent progress of immune-related therapies and prospect the future indirections in patients with R/R DLBCL.

Predictive Factors of Response to Immunotherapy in Lymphomas: A Multicentre Clinical Data Warehouse Study (PRONOSTIM)

Immunotherapy (IT) is a major therapeutic strategy for lymphoma, significantly improving patient prognosis. IT remains ineffective for a significant number of patients, however, and exposes them to specific toxicities. The identification predictive factors around efficacy and toxicity would allow better targeting of patients with a higher ratio of benefit to risk. PRONOSTIM is a multicenter and retrospective study using the Clinical Data Warehouse (CDW) of the Greater Paris University Hospitals network. Adult patients with Hodgkin lymphoma or diffuse large-cell B lymphoma treated with immune checkpoint inhibitors or CAR T (Chimeric antigen receptor T) cells between 2017 and 2022 were included. Analysis of covariates influencing progression-free survival (PFS) or the occurrence of grade ≥3 toxicity was performed. In total, 249 patients were included. From this study, already known predictors for response or toxicity of CAR T cells such as age, elevated lactate dehydrogenase, and elevated C-Reactive Protein at the time of infusion were confirmed. In addition, male gender, low hemoglobin, and hypo- or hyperkalemia were demonstrated to be potential predictive factors for progression after CAR T cell therapy. These findings prove the attractiveness of CDW in generating real-world data, and show its essential contribution to identifying new predictors for decision support before starting IT.

Programmed Death 1 (PD-1) Expression in Relapsing and Remitting Hodgkin Lymphoma as Prognostic Factor

BACKGROUND

Programmed death ligand 1 (PD-L1) plays critical role in PD-1-dependent immunity suppress. Abnormal PD-L1 expression has shown to be directly related to poor prognosis and drug resistance in cancer patients. Hence, we aimed to evaluate PD-L1 expression in relapsing and remitting Hodgkin lymphoma (HL) as a prognostic factor.

METHODS

In this cross-sectional study, 100 patients with HL between 2007 and 2015, were included. A thin section of tumor tissue fixed and processed on slides, stained by immunohistochemistry (IHC) PD-L1 specific antibodies. The clinical, imaging and pathology information of patients were obtained using case reading and by retrospective follow-up. The status of recurrence or improvement was determined after 5 years of diagnosis. GraphPad Prism v.8 was used for analysis.

RESULTS

of 100 HL cases, the mean age of 33 relapsed group cases was significantly higher than remission group (p-value = 0.006), and gender was not significant however majority of cases in both groups were male. The frequency of PD-L1 expression found in 49% of all patients. A significant relationship was found between the expression of PD-L1 and disease progression, HL subtype, stage of tumor (p-value<0.05). High expression of PD-L1 found in majority of relapse group and low expression in remission group.

CONCLUSION

PD-L1 expression assessment in HL patients is a valuable tool for prediction of the disease subtype, progression, stage, and treatment outcome. IHC method as an available, simple, rather cheap, and efficient tool could use for evaluation of PD-L1 expression and predicting the prognosis of HL disease, elsewhere.

Discovering the fibroblastic reticular cell in the immune tumor microenvironment in lymphoma

The study of the cellular and molecular microenvironment in B cell lymphoma, especially diffuse large B cell lymphoma (DLBCL), has led to prognostic and therapeutic algorithms that may improve patient outcomes. Emerging gene signature panels provide a granular understanding of DLBCL based on the immune tumor microenvironment (iTME). In addition, some gene signatures identify lymphomas that are more responsive to immune-based treatment, indicating that the iTME has a biological signature that could affect outcomes when targeted. In this issue of the JCI, Apollonio et al. report on fibroblastic reticular cells (FRCs) as potential targets in aggressive lymphoma. FRCs interacted with lymphoma cells and induced a state of chronic inflammation that suppressed immune function by impeding optimal T cell migration and inhibiting CD8+ T cell lytic function. These findings suggest that manipulating the iTME by directly targeting FRCs may enhance responses to immunotherapy in DLBCL.

Unraveling the Immune Microenvironment in Classic Hodgkin Lymphoma: Prognostic and Therapeutic Implications

Classic Hodgkin lymphoma (cHL) is a lymphoid neoplasm composed of rare neoplastic Hodgkin and Reed-Sternberg (HRS) cells surrounded by a reactive tumor microenvironment (TME) with suppressive properties against anti-tumor immunity. TME is mainly composed of T cells (CD4 helper, CD8 cytotoxic and regulatory) and tumor-associated macrophages (TAMs), but the impact of these cells on the natural course of the disease is not absolutely understood. TME contributes to the immune evasion of neoplastic HRS cells through the production of various cytokines and/or the aberrant expression of immune checkpoint molecules in ways that have not been fully understood yet. Herein, we present a comprehensive review of findings regarding the cellular components and the molecular features of the immune TME in cHL, its correlation with treatment response and prognosis, as well as the potential targeting of the TME with novel therapies. Among all cells, macrophages appear to be a most appealing target for immunomodulatory therapies, based on their functional plasticity and antitumor potency.

Efficacy of Immune Checkpoint Blockade and Biomarkers of Response in Lymphoma: A Narrative Review

Immune checkpoint blockade (ICB) has revolutionized the prognosis of several advanced-stage solid tumors. However, its success has been far more limited in hematological malignancies and is mostly restricted to classical Hodgkin lymphoma (cHL) and primary mediastinal B cell lymphoma (PMBCL). In patients with non-Hodgkin lymphoma (NHL), response to PD-1/PD-L1 ICB monotherapy has been relatively limited, although some subtypes are more sensitive than others. Numerous predictive biomarkers have been investigated in solid malignancies, such as PD-L1 expression, tumor mutational burden (TMB) and microsatellite instability (MSI), among others. This review aims to appraise the current knowledge on PD-1/PD-L1 ICB efficacy in lymphoma when used either as monotherapy or combined with other agents, and describes potential biomarkers of response in this specific setting.

Tackling the dysregulated immune-checkpoints in classical Hodgkin lymphoma: bidirectional regulations between the microenvironment and Hodgkin/Reed-Sternberg cells

Immune evasion is considered one of the modern hallmarks of cancer and is a key element in the pathogenesis of classical Hodgkin Lymphoma (cHL). This haematological cancer achieves effective avoidance of the host's immune system by overexpressing the PD-L1 and PD-L2 proteins on the surface of the neoplastic cells. Subversion of the PD-1/PD-L axis, however, is not the sole contributor to immune evasion in cHL, as the microenvironment nurtured by the Hodgkin/Reed-Sternberg cells is a major player in the creation of a biological niche that sustains their survival and hinders immune recognition. In this review, we will discuss the physiology of the PD-1/PD-L axis and how cHL is able to exploit a plethora of different molecular mechanisms to build an immunosuppressive microenvironment and achieve optimal immune evasion. We will then discuss the success obtained by checkpoint inhibitors (CPI) in treating cHL, both as single agents and as part of combination strategies, analysing the rationale for their combination with traditional chemotherapeutic compounds and the proposed mechanisms of resistance to CPI immunotherapy.

Identification and Interpretation of eQTL and eGenes for Hodgkin Lymphoma Susceptibility

Genome-wide association studies (GWAS) have revealed approximately 100 genomic signals associated with Hodgkin lymphoma (HL); however, their target genes and underlying mechanisms causing HL susceptibility remain unclear. In this study, transcriptome-wide analysis of expression quantitative trait loci (eQTL) was conducted to identify target genes associated with HL GWAS signals. A mixed model, which explains polygenic regulatory effects by the genomic covariance among individuals, was implemented to discover expression genes (eGenes) using genotype data from 462 European/African individuals. Overall, 80 eGenes were identified to be associated with 20 HL GWAS signals. Enrichment analysis identified apoptosis, immune responses, and cytoskeletal processes as functions of these eGenes. The eGene of rs27524 encodes ERAP1 that can cleave peptides attached to human leukocyte antigen in immune responses; its minor allele may help Reed-Sternberg cells to escape the immune response. The eGene of rs7745098 encodes ALDH8A1 that can oxidize the precursor of acetyl-CoA for the production of ATP; its minor allele may increase oxidization activity to evade apoptosis of pre-apoptotic germinal center B cells. Thus, these minor alleles may be genetic risk factors for HL susceptibility. Experimental studies on genetic risk factors are needed to elucidate the underlying mechanisms of HL susceptibility and improve the accuracy of precision oncology.

New molecular targets in Hodgkin and Reed-Sternberg cells

Recent discoveries shed light on molecular mechanisms responsible for classical Hodgkin lymphoma (HL) development and progression, along with features of Hodgkin - Reed and Sternberg cells (HRS). Here, we summarize current knowledge on characteristic molecular alterations in HL, as well as existing targeted therapies and potential novel treatments for this disease. We discuss the importance of cluster of differentiation molecule 30 (CD30) and the programmed cell death-1 protein (PD-1) and ligands (PD-L1/2), and other molecules involved in immune modulation in HL. We highlight emerging evidence indicating that the altered function of SWI/SNF-type chromatin remodeling complexes, PRC2, and other epigenetic modifiers, contribute to variations in chromatin status, which are typical for HL. We postulate that despite of the existence of plentiful molecular data, the understanding of HL development remains incomplete. We therefore propose research directions involving analysis of reverse signaling in the PD-1/PD-L1 mechanism, chromatin remodeling, and epigenetics-related alterations, in order to identify HL features at the molecular level. Such attempts may lead to the identification of new molecular targets, and thus will likely substantially contribute to the future development of more effective targeted therapies.

Advances in the treatment of Hodgkin's lymphoma (Review)

Hodgkin's lymphoma (HL) is a unique B‑cell lymphoproliferative malignancy that has a critical pathogenesis characterized by a sparse population of Hodgkin and Reed‑Sternberg cells surrounded by numerous dysfunctional immune cells. Although systemic chemotherapy with or without radiotherapy, has significantly improved the prognosis of the majority of patients with HL, a subset of patients remains refractory to first‑line therapy or relapse after achieving an initial response. With the increased understanding of the biology and microenvironment of HL, novel strategies with notable efficacy and manageable toxicity, including targeted therapies, immunotherapy and cell therapy have emerged. The present review summarizes the progress made in developing novel therapies for HL and discusses future research directions in HL therapy.

Molecular Evolution of Classic Hodgkin Lymphoma Revealed Through Whole-Genome Sequencing of Hodgkin and Reed Sternberg Cells

The rarity of malignant Hodgkin and Reed Sternberg (HRS) cells in classic Hodgkin lymphoma (cHL) limits the ability to study the genomics of cHL. To circumvent this, our group has previously optimized fluorescence-activated cell sorting to purify HRS cells. Using this approach, we now report the whole-genome sequencing landscape of HRS cells and reconstruct the chronology and likely etiology of pathogenic events leading to cHL. We identified alterations in driver genes not previously described in cHL, APOBEC mutational activity, and the presence of complex structural variants including chromothripsis. We found that high ploidy in cHL is often acquired through multiple, independent chromosomal gains events including whole-genome duplication. Evolutionary timing analyses revealed that structural variants enriched for RAG motifs, driver mutations in B2M, BCL7A, GNA13, and PTPN1, and the onset of AID-driven mutagenesis usually preceded large chromosomal gains. This study provides a temporal reconstruction of cHL pathogenesis.

SIGNIFICANCE

Previous studies in cHL were limited to coding sequences and therefore not able to comprehensively decipher the tumor complexity. Here, leveraging cHL whole-genome characterization, we identify driver events and reconstruct the tumor evolution, finding that structural variants, driver mutations, and AID mutagenesis precede chromosomal gains. This article is highlighted in the In This Issue feature, p. 171.

Classic Hodgkin lymphoma with marked granulomatous reaction: A clinicopathologic study of 20 cases

Granulomatous reactions can be associated with various types of lymphoma, most commonly classic Hodgkin lymphoma (CHL). In some cases, the granulomatous reaction is extensive, obscuring the presence of neoplastic cells and potentially leading to delayed diagnosis and treatment. It is unknown if this subgroup of CHL has any unique clinicopathologic features. Here, we assessed the clinical and pathological features of 20 cases of CHL with a marked granulomatous reaction, defined in this study as granulomas representing ≥50% of the total cellularity/space of the specimen. This cohort of patients showed a male predominance (M:F ratio = 1.9:1) and 75% of patients were older than 40 years. Nineteen (95%) patients presented with lymphadenopathy with the neck/supraclavicular areas being most commonly involved (11/19; 58%). Advanced stage (III-IV) disease and B symptoms were present in 69% and 64% of patients, respectively. The morphologic features of these neoplasms fit best with mixed cellularity type. The Hodgkin and Reed-Sternberg (HRS) cells were positive for CD30, PAX5 (weak), pSTAT3 (80%), CD15 (70%), PD-L1 (67%), EBV-encoded small RNA (EBER)/LMP1 (50%) and CD20 (42%), and were negative for CD3, CD5, CD45, ALK and pERK. The histiocytes of the granulomas were positive for PD-L1 (67%), pSTAT3 (50%), and were negative for pERK and cyclin D1. Next generation sequencing using a 162-gene panel was negative for mutations in 4 cases. With a median follow-up of 58.9 months (range, 3.4-199.2 months), the median overall survival was 111 months and the 5-year overall survival was 78%. In summary, patients with CHL and a marked granulomatous reaction can present a diagnostic challenge and the pathologist must be alert to the possible presence of CHL to avert potential misdiagnosis. The histiocytes in the granulomas frequently express PD-L1, likely through the activation of the JAK/STAT pathway, suggesting a potential role for PD-1 blockade therapy in these patients.

Characterisation of tumor microenvironment and prevalence of CD274/PD-L1 genetic alterations difference in colorectal Cancer

BACKGROUND

Large-scale genomic alterations, especially CD274/PD-L1 gene amplification, have great impact on anti-PD-1 efficacy on cancers such as Hodgkin's lymphoma. However, the prevalence of PD-L1 genetic alterations in colorectal cancer (CRC) and its correlation with the tumor immune microenvironment and clinical implications remain unknown.

MATERIALS AND METHODS

PD-L1 genetic alterations were evaluated in 324 patients with newly diagnosed CRC including 160 mismatch repair-deficient (dMMR) patients and 164 mismatch repair-proficient (pMMR) patients using fluorescence in situ hybridization (FISH) method. The correlation between PD-L1 and the expression of the common immune markers was analyzed.

RESULTS

Totally 33 (10.2%) patients were identified with aberrant PD-L1 genetic alternations including deletion (2.2%), polysomy (4.9%), and amplification (3.1%); They had more aggressive features such as advanced stage (P = 0.02), shorter overall survival (OS) (P < 0.001) than patients with disomy. The aberrations correlated with positive lymph node (PLN) (p = 0.001), PD-L1 expression by immunohistochemistry (IHC) in tumor cells (TCs) or tumor-infiltrated immunocytes (ICs) (both p < 0.001), and pMMR (p = 0.029). When dMMR and pMMR were analyzed independently, the correlations of aberrant PD-L1 genetic alterations with PD-1 expression (p = 0.016), CD4 + T cells (p = 0.032), CD8 T + cells (p = 0.032) and CD68 + cells (p = 0.04) were only found in dMMR cohort.

CONCLUSIONS

The prevalence of PD-L1 genetic alterations was relatively low in CRC, but the aberrations usually correlate with aggressive nature. The correlation between PD-L1 genetic alterations and tumor immune features was only observed in dMMR CRC.

Diagnosis and management of Hodgkin lymphoma in children, adolescents, and young adults

Advances in the management of Hodgkin lymphoma in children, adolescents and young adult have resulted in survival outcomes exceeding 90%. The risk of late toxicity, however, remains a significant concern for survivors of HL and the focus of modern trials have been to advance cure rates while reducing long term toxicity. This has been accomplished through response-adapted treatment approaches and the incorporation of novel agents, many of which target the unique interaction between the Hodgkin and Reed Sternberg cells and the tumor microenvironment. In addition, an improved understanding of prognostic markers, risk stratification, and the biology of this entity in children and AYAs may allow us to further tailor therapy. This review focuses on the current management of HL in the upfront and relapsed settings, recent advances in novel agents that target HL and the tumor microenvironment, and promising prognostic markers that may help guide the future management of HL.

Checkpoint inhibitor-based salvage regimens prior to autologous stem cell transplant improve event-free survival in relapsed/refractory classic Hodgkin lymphoma

Clinical trials of novel salvage therapies have encouraging outcomes for relapsed/refractory transplant-eligible classic Hodgkin lymphoma (R/R cHL) but comparison with conventional chemotherapy is lacking. Herein, we report the final analysis of a multicenter retrospective cohort of R/R cHL assessing outcomes by type of salvage therapy before autologous stem cell transplant (ASCT). R/R cHL patients who underwent ASCT at 14 institutions across the United States were included. Outcomes were compared among patients receiving conventional chemotherapy, brentuximab vedotin (BV) + chemotherapy, BV alone, and a checkpoint inhibitor (CPI)-based regimens before ASCT. Study endpoints included event-free survival (EFS), progression-free survival (PFS), and overall survival (OS). All endpoints are defined from relapse. Of 936 patients, 728 received conventional chemotherapy, 73 received BV + chemotherapy, 70 received BV alone, and 65 received CPI-based regimens prior to ASCT. When adjusted for time to relapse, pre-ASCT response and use of BV maintenance, patients receiving CPI-based regimens had superior 2-year EFS compared to conventional chemotherapy, BV + chemotherapy, and BV alone (79.7, 49.6, 62.3, and 36.9%, respectively, p < .0001). Among 649 patients transplanted after 1 line of salvage therapy, CPI-based regimens were associated with superior 2-year PFS compared to conventional chemotherapy (98% vs. 68.8%, hazard ratio: 0.1, 95% confidence interval: 0.03-0.5, p < .0001). OS did not differ by pre-ASCT salvage regimen. In this large multicenter retrospective study, CPI-based regimens improved EFS and PFS compared to other salvage regimens independent of pre-ASCT response. These data support earlier sequencing of CPI-based regimens in R/R cHL in the pre-ASCT setting.

PD-L1 immunohistochemistry assay optimization to provide more comprehensive pathological information in classic Hodgkin lymphoma

Overexpression of PD-L1 can be a predictive marker for anti-PD-1 therapeutic efficacy in classic Hodgkin lymphoma (CHL); however, harmonization of different IHC assays remains to be accomplished, and interpretations of PD-L1 immunostaining results remain controversial in CHL. In this study, we sought to optimize the PD-L1 immunohistochemistry (IHC) assay in CHL. All tests were performed on a tumour tissue microarray established from 54 CHL cases. Three IHC antibodies (405.9A11, SP142, 22C3) for detecting PD-L1 expression were compared semi quantitatively with the RNAscope assay (No. 310035, ACD), and the difference in the expression in background immune cells (ICs) between assays and the associations of expression levels with densities of TILs/TAMs were also analysed. 405.9A11 demonstrated best specificity in HRS cells and best sensitivity in ICs. Positive expression of PD-L1 was more frequent in ICs (85.2%) than in HRS cells (48.1%). Different subgroups of background ICs, including tumour-associated macrophages (TAMs), were assessed and scored for CD4, CD8, FOXP3, and CD163 expression. PD-L1 expression on ICs was the factor most associated with the density of TAMs. 405.9A11 provided the most convincing PD-L1 expression results. Pathologists should report PD-L1 expression in a combined manner, including both the status of HRS cells and the percentage of PD-L1-positive ICs.

PD-L1 gene amplification and focality: relationship with protein expression

PD-L1 (CD274) amplification occurs in a small subset of malignancies and may predict anti-PD-1/PD-L1 immunotherapy responsiveness. We hypothesized that both copy number (CN) and focality of cancer-related PD-L1 amplifications impact protein expression, and, thus, analyzed solid tumors that underwent comprehensive genomic profiling between March 2016 and February 2022 at Foundation Medicine. PD-L1 CN alterations were detected using a comparative genomic hybridization-like method. PD-L1 CN changes were correlated with PD-L1 protein expression (DAKO 22C3 antibody) by immunohistochemistry (IHC). Overall, 60,793 samples were analyzed (most frequent histologies: lung adenocarcinoma (20%), colon adenocarcinoma (12%), lung squamous carcinoma (8%)). Using a definition of CD274 CN ≥ specimen ploidy +4 (6 copies), 1.21% of tumors (738/60,793) were PD-L1 amplified. Focality category distribution was as follows: <0.1 mB (n=18 (2.4%)), ≥0.1 to <4 mB (n=230 (31.1%)), ≥4 to <20 mB (n=310 (42%)), ≥20mB (n=180 (24.4%)). Lower levels of PD-L1 amplification (below specimen ploidy +4) were more frequently non-focal amplifications compared to higher levels. In addition, more focal amplification (<0.1 mB) correlated with higher PD-L1 IHC expression. Median tumor proportion score (TPS) for samples with PD-L1 amplification (ploidy ≥+4) according to focality were 87.5% (<0.1 mB), 80% (≥0.1 to <4 mB), 40% (≥4 to <20 mB), 1% (≥20mB). In specimens with PD-L1 ploidy less than +4, but highly focal (<0.1 mB), the 75th percentile of PD-L1 expression by TPS was 80%. Conversely, non-focal (≥20 mB) PD-L1 amplification (ploidy ≥+4) can present high PD-L1 expression (TPS≥50%), albeit infrequently (0.09% of our cohort). In conclusion, PD-L1 expression measured by IHC is influenced by PD-L1 amplification level and focality. Further correlation between amplification, focality, protein expression and therapeutic outcome for PD-L1 and other targetable genes warrants exploration.

Thrombocytopenia, anasarca, and renal insufficiency as severe and rare complications of Hodgkin lymphoma: a case report

BACKGROUND

Patients with Hodgkin lymphoma exhibit various clinical presentations. Needle biopsy of the lymph nodes is a minimally invasive procedure and a useful diagnostic method for malignant lymphomas. However, at times it is difficult to differentiate malignant lymphomas from reactive lymph node changes using a small amount of biopsy material.

CASE PRESENTATION

A 77-year-old Japanese man was referred to the emergency department of our hospital owing to high fever and disturbance of consciousness. We diagnosed sepsis due to an acute biliary tract infection because he presented with Charcot's triad-fever, jaundice, and right-sided abdominal pain. However, he did not respond well to antimicrobial therapy and his high fever persisted. Considering the swelling of the right cervical, mediastinal, and intraperitoneal lymph nodes and splenomegaly detected on computed tomography, a differential diagnosis of malignant lymphoma was needed. Hence, we performed a needle biopsy of the right cervical lymph node; however, the amount of sample obtained was insufficient in establishing a definitive diagnosis of malignant lymphoma. Furthermore, during hospitalization, the patient developed thrombocytopenia, anasarca, and renal insufficiency. These symptoms seemed to be the typical signs of the thrombocytopenia, anasarca, fever, reticulin fibrosis or renal insufficiency, and organomegaly syndrome. Next, an external incisional mass biopsy of the right cervical lymph node was performed, which helped identify Hodgkin and Reed-Sternberg cells. Collectively, we established a definitive diagnosis of Hodgkin lymphoma with lymphoma-associated hemophagocytic syndrome.

CONCLUSIONS

This case highlights the importance of performing an external incisional mass biopsy of the lymph nodes for the early diagnosis and treatment, if malignant lymphoma is strongly suspected.

Intravascular Large B-Cell Lymphoma Genomic Profile Is Characterized by Alterations in Genes Regulating NF-κB and Immune Checkpoints

Intravascular large B-cell lymphoma (IVLBCL) is an uncommon lymphoma with an aggressive clinical course characterized by selective growth of tumor cells within the vessels. Its pathogenesis is still uncertain and there is little information on the underlying genomic alterations. In this study, we performed a clinicopathologic and next-generation sequencing analysis of 15 cases of IVLBCL using a custom panel for the detection of alterations in 68 recurrently mutated genes in B-cell lymphomagenesis. Six patients had evidence of hemophagocytic syndrome. Four patients presented concomitantly a solid malignancy. Tumor cells outside the vessels were observed in 7 cases, 2 with an overt diffuse large B-cell cell lymphoma. In 4 samples, tumor cells infiltrated lymphatic vessel in addition to blood capillaries. Programmed death-ligand 1 (PD-L1) was positive in tumor cells in 4 of 11 evaluable samples and in macrophages intermingled with tumor cells in 8. PD-L1 copy number gains were identified in a higher proportion of cases expressing PD-L1 than in negative tumors. The most frequently mutated gene was PIM1 (9/15, 60%), followed by MYD88L265P and CD79B (8/15, 53% each). In 6 cases, MYD88L265P and CD79B mutations were detected concomitantly. We also identified recurrent mutations in IRF4 , TMEM30A , BTG2 , and ETV6 loci (4/15, 27% each) and novel driver mutations in NOTCH2 , CCND3 , and GNA13 , and an IRF4 translocation in 1 case each. The mutational profile was similar in patients with and without evidence of hemophagocytic syndrome and in cases with or without dissemination of tumor cells outside the vessels. Our results confirm the relevance of mutations in B-cell receptor/nuclear factor-κB signaling and immune escape pathways in IVLBCL and identify novel driver alterations. The similar mutational profile in tumors with extravascular dissemination suggests that these cases may also be considered in the spectrum of IVLBCL.

Immunotherapy for Hodgkin lymphoma: From monoclonal antibodies to chimeric antigen receptor T-cell therapy

Although up to 80 % of Hodgkin lymphoma (HL) patients are cured with first-line therapy, relapsed/refractory HL remains a major clinical obstacle and is fatal for patients who are not candidates for autologous stem cell transplantation (ASCT) or relapse after treatment. Several immune-based approaches have been investigated in recent years with the aim of exerting a possible antitumor effect through the immune system response to cancer cells. Clinical studies on novel agents, including brentuximab vedotin (BV) and PD-1 inhibitors, have successfully demonstrated their effectiveness in relapsed disease after ASCT. Additionally, studies examining combination strategies with the goal of reducing the risk of relapse and chemotherapy-related toxicity have showed encouraging results, mainly in untreated early unfavorable or advanced stage classical HL (cHL). Other non-approved immunotherapies such as camidanlumab tesirine, bispecific CD30/CD16A antibody, and CD30 chimeric antigen receptor (CAR) T-cell therapy are promising approaches that may reinforce the therapeutic arsenal available to patients.

Analysis and therapeutic targeting of the EP300 and CREBBP acetyltransferases in anaplastic large cell lymphoma and Hodgkin lymphoma

Anaplastic large cell lymphoma (ALCL) and classical Hodgkin lymphoma (HL) share a similar cytological and high surface expression of CD30, and novel therapeutic strategies are needed. The EP300 and CREBBP acetyltransferases play essential roles in the pathogenesis of non-Hodgkin B cell lymphoma, but their functions in ALCL and HL are unknown. In the current study, we investigated the physiological roles of EP300 and CREBBP in both ALCL and HL, and exploited the therapeutic potential of EP300/CREBBP small molecule inhibitors that target either the HAT or bromodomain activities. Our studies demonstrated distinct roles for EP300 and CREBBP in supporting the viability of ALCL and HL, which was bolstered by the transcriptome analyses. Specifically, EP300 but not CREBBP directly modulated the expression of oncogenic MYC/IRF4 network, surface receptor CD30, immunoregulatory cytokines IL10 and LTA, and immune checkpoint protein PD-L1. Importantly, EP300/CREBBP HAT inhibitor A-485 and bromodomain inhibitor CPI-637 exhibited strong activities against ALCL and HL in vitro and in xenograft mouse models, and inhibited PD-L1 mediated tumor immune escape. Thus, our studies revealed critical insights into the physiological roles of EP300/CREBBP in these lymphomas, and provided opportunities for developing novel strategies for both targeted and immune therapies.

Genetic lesions and targeted therapy in Hodgkin lymphoma

Hodgkin lymphoma is a special type of lymphoma in which tumor cells frequently undergo multiple genetic lesions that are associated with accompanying pathway abnormalities. These pathway abnormalities are dominated by active signaling pathways, such as the JAK-STAT (Janus kinase-signal transducer and activator of transcription) pathway and the NFκB (nuclear factor kappa-B) pathway, which usually result in hyperactive survival signaling. Targeted therapies often play an important role in hematologic malignancies, such as CAR-T therapy (chimeric antigen receptor T-cell immunotherapy) targeting CD19 and CD22 in diffuse large B-cell lymphoma, while in Hodgkin lymphoma, the main targets of targeted therapies are CD30 molecules and PD1 molecules. Drugs targeting other molecules are also under investigation. This review summarizes the actionable genetic lesions, current treatment options, clinical trials for Hodgkin lymphoma and the potential value of those genetic lesions in clinical applications.

PDJ amplicon in triple negative breast cancer

Amplification of chromosome 9p24.1 targeting PD-L1, PD-L2, and JAK2 (PDJ amplicon) is present in subsets of triple negative breast cancers (TNBCs) and is associated with poor clinical outcomes. However, the prevalence of PDJ+ TNBCs varies extensively across studies applying different methods for interrogating samples of interest. To rigorously assess the prevalence of PDJ amplicons in TNBC, its prognostic value and whether it is enriched by chemotherapy, we interrogated 360 TNBC samples including 74 surgical resections from patients treated in the neoadjuvant setting, and tissue microarrays (TMAs) with 31 cases from African American women and 255 resected non-metastatic cases, with a 3 color fluorescence in situ hybridization (FISH) assay targeting the 9p24.1 PDJ amplicon, 9q24.3, and 9q34.1. Samples with mean PDJ signal of > 4.5 copies, and ratios of PDJ/9q24 ≥ 2 and/or PDJ/9q34.1 ≥ 2 were called amplified (PDJ+). Correlative analyses included the association of tumor infiltrating lymphocytes (TILs) with PDJ amplicons in TNBCs. In addition, we investigated intratumor copy number of PDJ amplicons in PDJ+ and PDJ- TNBCs. Matched pre- and post-neoadjuvant treatment biopsies were available from patients (n = 6) to evaluate the effects of therapy on PDJ status. Our study provides a rigorous analysis of the prevalence, distribution, and clinical correlatives of the PDJ amplicon in TNBC.

Brentuximab vedotin plus nivolumab after autologous haematopoietic stem-cell transplantation for adult patients with high-risk classic Hodgkin lymphoma: a multicentre, phase 2 trial

BACKGROUND

After autologous haematopoietic stem-cell transplantation (HSCT), consolidation with brentuximab vedotin in patients with high-risk relapsed or refractory classic Hodgkin lymphoma has been shown to improve progression-free survival compared with placebo. Brentuximab vedotin plus nivolumab is a safe and effective treatment for relapsed or refractory classic Hodgkin lymphoma; therefore, we aimed to evaluate the safety and activity of this drug combination post-autologous HSCT consolidation in patients with high-risk relapsed or refractory classic Hodgkin lymphoma.

METHODS

We did a multicentre phase 2 trial at five centres in the USA. Eligible patients were aged 18 years or older with high-risk relapsed or refractory classic Hodgkin lymphoma, had an ECOG performance status of 0-2, and had adequate organ and bone marrow function. Enrolled patients received brentuximab vedotin (1·8 mg/kg) and nivolumab (3 mg/kg) intravenously starting 30-60 days after autologous HSCT on day 1 of each 21-day cycle for up to 8 cycles. Nivolumab dose reduction was not allowed. Brentuximab vedotin dose reduction to 1·2 mg/kg was permitted. If one drug was discontinued because of a toxic effect, the other could be continued. The primary endpoint was 18-month progression-free survival in all treated patients. This study is registered with ClinicalTrials.gov, number NCT03057795.

FINDINGS

Between May 3, 2017, and July 13, 2019, 59 patients were enrolled and received the study therapy. Patients initiated brentuximab vedotin plus nivolumab for a median of 54 days (IQR 46-58) after autologous HSCT and received a median of 8 cycles (8-8). 34 (58%) of 59 patients were male, 29 (49%) completed 8 cycles of brentuximab vedotin plus nivolumab, and 45 (76%) completed 8 cycles of at least one drug. The median follow-up time was 29·9 months (IQR 24·6-34·8). The 18-month progression-free survival in all 59 patients was 94% (95% CI 84-98). The most common adverse events were sensory peripheral neuropathy (31 [53%] of 59) and neutropenia (25 [42%]), and immune-related adverse events requiring corticosteroids occurred in 17 (29%) of 59 patients. No treatment-related deaths were observed.

INTERPRETATION

Brentuximab vedotin plus nivolumab was highly active post-autologous HSCT consolidation for patients with high-risk relapsed or refractory classic Hodgkin lymphoma, most of whom had previous exposure to either brentuximab vedotin or PD-1 blockade. Combination immunotherapy in this setting should be further studied in patients with classic Hodgkin lymphoma with further refinement of the regimen to mitigate toxic effects, particularly in high-risk patients in whom more intensive therapy to prevent relapse is warranted.

FUNDING

Bristol Myers Squibb, Leukemia and Lymphoma Society, Lymphoma Research Foundation, and National Cancer Institute of the National Institutes of Health.