Major Histocompatibility Complex Class II and Programmed Death Ligand 1 Expression Predict Outcome After Programmed Death 1 Blockade in Classic Hodgkin Lymphoma

Viral oncogenesis in cancer: from mechanisms to therapeutics

The year 2024 marks the 60th anniversary of the discovery of the Epstein-Barr virus (EBV), the first virus confirmed to cause human cancer. Viral infections significantly contribute to the global cancer burden, with seven known Group 1 oncogenic viruses, including hepatitis B virus (HBV), human papillomavirus (HPV), EBV, Kaposi sarcoma-associated herpesvirus (KSHV), hepatitis C virus (HCV), human T-cell leukemia virus type 1 (HTLV-1), and human immunodeficiency virus (HIV). These oncogenic viruses induce cellular transformation and cancer development by altering various biological processes within host cells, particularly under immunosuppression or co-carcinogenic exposures. These viruses are primarily associated with hepatocellular carcinoma, gastric cancer, cervical cancer, nasopharyngeal carcinoma, Kaposi sarcoma, lymphoma, and adult T-cell leukemia/lymphoma. Understanding the mechanisms of viral oncogenesis is crucial for identifying and characterizing the early biological processes of virus-related cancers, providing new targets and strategies for treatment or prevention. This review first outlines the global epidemiology of virus-related tumors, milestone events in research, and the process by which oncogenic viruses infect target cells. It then focuses on the molecular mechanisms by which these viruses induce tumors directly or indirectly, including the regulation of oncogenes or tumor suppressor genes, induction of genomic instability, disruption of regular life cycle of cells, immune suppression, chronic inflammation, and inducing angiogenesis. Finally, current therapeutic strategies for virus-related tumors and recent advances in preclinical and clinical research are discussed.

PD-L1/PD-L2 genetic profile in the molecular cytogenetic classification of classic Hodgkin lymphoma

Genomic imbalance at 9p24.1 locus, the chromosome region that maps PD-L1 and PD-L-2 (programmed death ligand 1 and 2) genes, is a recurrent alteration in classic Hodgkin lymphoma (cHL). We analyzed 9p24.1 imbalance by fluorescence in situ hybridization assay on formalin-fixed paraffin-embedded biopsies of 28 patients with newly diagnosed cHL to characterize the genetic profiles. Results were correlated with PD-L1 (H-score) and LMP-1 (latent membrane protein 1) protein expression of Epstein-Barr virus by immunohistochemistry and clinical features. Genomic alterations in Hodgkin/Reed Sternberg (H/RS) cells were classified as amplification, copy gain, and polysomy. Three molecular cytogenetic groups were defined according to the type and frequency of the copy number alteration: Group A (with amplification) 32%, Group G (with > 50% cells with copy gains but without amplification) 36%, and Group P (with ≥ 50% cells with polysomies but without amplification) 32%. A different frequency of copy gains (p = 0.02) and polysomies (p ≤ 0.01) among groups was found. A negative correlation between the percentage of H/RS cells with polysomies and the PD-L1 protein expression (p ≤ 0.01) was observed. Tumor microenvironmental cells showed chromosome 9 monosomy particularly associated to Group P. The highest H-score mean value was observed in Group A (265.6), while Groups G and P showed 123 and 60.3 H-score, respectively. Group P showed the highest mean age (p = 0.036) and increased frequency of advanced stages, B symptoms, and extranodal involvement, while Groups A and G were associated with localized stages (p = 0.035) and bulky mass, highlighting the importance of 9p24.1 genomic imbalance profile in the biological characterization of cHL.

Advances in Hodgkin lymphoma research

Hodgkin lymphoma (HL) has been and still is the most enigmatic lymphoid malignancy in humans. Since the first molecular analysis of isolated Hodgkin and Reed-Sternberg (HRS) tumor cells of classic HL 30 years ago, substantial advances in our understanding of HL have been made. This review describes the cellular origin of HL, summarizes the current knowledge about the genetic lesions in HRS cells, and highlights the role of Epstein-Barr virus (EBV) in HL pathogenesis. Moreover, the pathobiological roles of altered gene expression and deregulated signaling pathways are discussed and key aspects of the HL microenvironment are presented.

Translational Advances in Oncogene and Tumor-Suppressor Gene Research

Cancer, characterized by the uncontrolled proliferation of cells, is one of the leading causes of death globally, with approximately one in five people developing the disease in their lifetime. While many driver genes were identified decades ago, and most cancers can be classified based on morphology and progression, there is still a significant gap in knowledge about genetic aberrations and nuclear DNA damage. The study of two critical groups of genes-tumor suppressors, which inhibit proliferation and promote apoptosis, and oncogenes, which regulate proliferation and survival-can help to understand the genomic causes behind tumorigenesis, leading to more personalized approaches to diagnosis and treatment. Aberration of tumor suppressors, which undergo two-hit and loss-of-function mutations, and oncogenes, activated forms of proto-oncogenes that experience one-hit and gain-of-function mutations, are responsible for the dysregulation of key signaling pathways that regulate cell division, such as p53, Rb, Ras/Raf/ERK/MAPK, PI3K/AKT, and Wnt/β-catenin. Modern breakthroughs in genomics research, like next-generation sequencing, have provided efficient strategies for mapping unique genomic changes that contribute to tumor heterogeneity. Novel therapeutic approaches have enabled personalized medicine, helping address genetic variability in tumor suppressors and oncogenes. This comprehensive review examines the molecular mechanisms behind tumor-suppressor genes and oncogenes, the key signaling pathways they regulate, epigenetic modifications, tumor heterogeneity, and the drug resistance mechanisms that drive carcinogenesis. Moreover, the review explores the clinical application of sequencing techniques, multiomics, diagnostic procedures, pharmacogenomics, and personalized treatment and prevention options, discussing future directions for emerging technologies.

Molecular determinants of response to neoadjuvant pembrolizumab plus chemotherapy in patients with high-risk, early-stage, triple-negative breast cancer: exploratory analysis of the open-label, multicohort phase 1b KEYNOTE-173 study

BACKGROUND

The multicohort, open-label, phase 1b KEYNOTE-173 study was conducted to investigate pembrolizumab plus chemotherapy as neoadjuvant therapy for triple-negative breast cancer (TNBC). This exploratory analysis evaluated features of the tumor microenvironment that might be predictive of response.

METHODS

Cell fractions from 20 paired samples collected at baseline and after one cycle of neoadjuvant pembrolizumab prior to chemotherapy initiation were analyzed by spatial localization (tumor compartment, stromal compartment, or sum of tumor and stromal compartments [total tumor]) using three six-plex immunohistochemistry panels with T-cell, myeloid cell, and natural killer cell components. Area under the receiver operating characteristic curve (AUROC) was used to assess associations between immune subsets and gene expression signatures (T-cell-inflamed gene expression profile [TcellinfGEP] and 10 non-TcellinfGEP signatures using RNA sequencing) and pathologic complete response (pCR).

RESULTS

At baseline, six immune subsets quantitated within the tumor compartment showed AUROC with 95% CIs not crossing 0.5, including CD11c+ cells (macrophage and dendritic cell [DC]: AUROC, 0.85; 95% confidence interval [CI] 0.63-1.00), CD11c+/MHCII+/CD163-/CD68- cells (DC: 0.76; 95% CI, 0.53-0.99), CD11c+/MHCII-/CD163-/CD68- cells (nonactivated/immature DC: 0.80; 95% CI 0.54-1.00), and CD11c+/CD163+ cells (M2 macrophage: 0.77; 95% CI 0.55-0.99). Other associations with pCR included baseline CD11c+/MHCII-/CD163-/CD68- (nonactivated/immature DC) within the total tumor (AUROC, 0.76; 95% CI 0.51-1.00) and the baseline CD11c/CD3 ratio within the tumor compartment (0.75; 95% CI 0.52-0.98). Changes in immune subsets following one cycle of pembrolizumab were not strongly associated with pCR. Although T-cell associations were relatively weak, specific CD8 subsets trended toward association. The AUROC for discriminating pCR based on TcellinfGEP was 0.55 (95% CI 0.25-0.85); when detrended by TcellinfGEP, AUROC varied for the non-TcellinfGEP signatures. TcellinfGEP expression trended higher in responders than in nonresponders when evaluating pCR.

CONCLUSIONS

Myeloid cell populations within the tumor compartment at baseline and TcellinfGEP show a promising trend toward an association with pCR in a small subgroup of patients with early-stage TNBC treated with neoadjuvant pembrolizumab plus chemotherapy.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02622074; registration date, December 2, 2015.

Integrating Novel Agents Into the Clinical Management of Classic Hodgkin Lymphoma

Classic Hodgkin lymphoma (cHL) is highly curable at all stages. Research efforts over the past few decades have largely focused on interim PET-adapted strategies for therapy de-escalation or intensification. The overarching goals have been to increase cure rates, minimize potential therapy-related effects, and optimize survivorship. Better understanding of the biology of cHL has led to the development and approval of effective novel agents including the antibody-drug conjugate brentuximab vedotin and the checkpoint inhibitor immunotherapies. In this review, we discuss recent trial results and how these agents are integrated into clinical practice with the goal of further optimizing outcomes.

Clinical use of circulating tumor DNA analysis in patients with lymphoma

The analysis of circulating tumor DNA (ctDNA) in liquid biopsy specimens has an established role for the detection of predictive molecular alterations and acquired resistance mutations in several tumors. The low-invasiveness of this approach allows for repeated sampling and dynamic monitoring of disease evolution. Originating from the entire body tumor bulk, plasma-derived ctDNA reflects intra- and interlesional genetic heterogeneity. In the management of lymphoma patients, ctDNA quantification at various timepoints of the patient's clinical history is emerging as a complementary tool that may improve risk stratification, assessment of treatment response and early relapse detection during follow-up, most prominently in patients with diffuse large B-cell lymphoma or classic Hodgkin lymphoma. While liquid biopsies have not yet entered standard-of-care treatment protocols in these settings, several trials have provided evidence that at least a subset of lymphoma patients may benefit from the introduction of liquid biopsies into daily clinical care. In parallel, continuous technological developments have enabled highly sensitive ctDNA assessment methods, which span from locus-specific techniques identifying single hotspot mutations, to sequencing panels and genome-wide approaches that explore broader genetic and epigenetic alterations. Here, we provide an overview of current methods and ongoing technical developments for ctDNA evaluation. We also summarize the most important data from a selection of clinical studies that have explored the clinical use of ctDNA in several lymphoma entities.

Uridine-cytidine kinase 2 is correlated with immune, DNA damage repair and promotion of cancer stemness in pan-cancer

Background

UCK2 (Uridine-Cytidine Kinase 2) is a promising prognostic marker for malignant tumors, but its association with immune infiltration and cancer stemness in pan-cancer remains to be fully understood. we find that gene UCK2 is closed related to RNA stemness scores (RNAss) and DNA stemness scores (DNAss), which is measured the tumor stemness. We also discover an association between UCK2 expression and immune cells by CIBERSORT algorithm, ESTIMATE algorithm and ssGSEA algorithm, especially, related to T cell, monocytes, mast cells, and macrophages. This study aims to shed light on the role and possible mechanism of UCK2 in pan-cancer.

Methods

We used the R programming language for pan-cancer bulk sequencing data analysis, which were obtained from the University of California, Santa Cruz (UCSC) datasets. UCSC database is a very useful for explore data from TCGA and other cancer genomics datasets, The data we explored at the UCK2 transcriptome level came from TCGA data in the UCSC database. We explored differential UCK2 expression between tumor and normal samples. Immunohistochemistry (IHC) was utilized to validate the expression of UCK2 in different types cancers using tumor tissue chips. The correlations of UCK2 with prognosis, genetic instability, DNA repair, cancer stem cell characteristics, and immune cell infiltration were investigated. Furthermore, single-cell datasets, acquired from the Gene Expression Omnibus (GEO) database, were used to validate the relationship between UCK2 and immune cells. GEO is a famous public genomics database supporting freely disseminates microarray data. Finally, we analyzed the correlation between UCK2 and drug sensitivity.

Results

UCK2 expression was observed to be high in most cancers and was remarkably related to the prognosis of pan-cancers. We found that the increased UCK2 expression was associated with higher genetic instability. Additionally, positive relationships were observed between UCK2 expression and mismatch repair genes, homologous recombination repair genes, and cancer stemness across different cancer types. There were significant correlations between UCK2 and T cells, monocytes, mast cells, and macrophages. Moreover, as expected, the immune checkpoint human leucocyte antigen (HLA) was found to be negatively related to UCK2. Similarly, UCK2 was also observed to have a negative association with major histocompatibility complex (MHC) genes. We noted that UCK2 had significant correlations with the sensitivity to various anti-cancer drug.

Conclusion

We have observed that UCK2 plays pivotal roles in prognosis and tumor immunity, and it is associated with DNA repair and cancer stemness. The UCK2 gene exhibits a strong correlation with the immune checkpoints HLA. This study highlights its potential impact on drug sensitivity.

Successful Treatment of a Patient Presenting with Simultaneous Diffuse Large B-Cell Lymphoma and Hodgkin Lymphoma: A Case Report

BACKGROUND Simultaneously occuring diffuse large B-cell lymphoma (DLBCL) and Hodgkin lymphoma (HL) is extremely rare. Generally, patients with CD20-positive DLBCL receive rituximab, cyclophosphamide, vincristine, doxorubicin, prednisone (R-CHOP) regimen, while those with HL receive brentuximab vedotin, doxorubicin, vinblastine, dacarbazine (A-AVD) regimen as first-line therapy. Establishing a strategy for treating both lymphoma subtypes concurrently is thus very difficult. We report successful treatment of a patient simultaneously diagnosed with advanced DLBCL and HL. CASE REPORT A 20-year-old man visited the Hematology Department of Kyungpook National University Hospital after the diagnosis of germinal center B-cell DLBCL in the kidney and HL (nodular sclerosis type) in the neck lymph node. His DLBCL was classified as Ann Arbor stage IV with an International Prognostic Index score of 4, a high-risk group. Six cycles of R-CHOP therapy were planned, and central nervous system prophylaxis with intrathecalmethotrexate was added because of the high-risk features of central nervous system involvement. After completing 6 cycles of chemotherapy, without significant adverse events (Deauville score of 1), complete remission was confirmed. Then, the patient decided to undergo consolidative autologous stem cell transplantation (auto-SCT). He received busulfan, cyclophosphamide, and etoposide conditioning regimen, after which auto-SCT was conducted in April 2021. After auto-SCT, the patient was undergoing regular check-ups and doing well, without obvious disease relapse or specific symptoms. He maintained a disease-free status for 40 months to date. CONCLUSIONS Our case showed that R-CHOP regimen was effective not only for DLBCL but also for HL. Notably, consolidative upfront auto-SCT should be considered for a deeper response.

Cancer-specific innate and adaptive immune rewiring drives resistance to PD-1 blockade in classic Hodgkin lymphoma

Hodgkin Reed-Sternberg (HRS) cells of classic Hodgkin lymphoma (cHL), like many solid tumors, elicit ineffective immune responses. However, patients with cHL are highly responsive to PD-1 blockade, which largely depends on HRS cell-specific retention of MHC class II and implicates CD4+ T cells and additional MHC class I-independent immune effectors. Here, we utilize single-cell RNA sequencing and spatial analysis to define shared circulating and microenvironmental features of the immune response to PD-1 blockade in cHL. Compared with non-responders, responding patients have more circulating CD4+ naïve and central memory T cells and B cells, as well as more diverse CD4+ T cell and B cell receptor repertoires. Importantly, a population of circulating and tumor-infiltrating IL1β+ monocytes/macrophages is detectable in patients with cHL but not healthy donors, and a proinflammatory, tumor-promoting signature of these circulating IL1β+ monocytes is associated with resistance to PD-1 blockade in cHL. Altogether, our findings reveal extensive immune rewiring and complementary roles of CD4+ T cells, B cells and IL1β+ monocytes in the response to PD-1 blockade and suggest that these features can be captured with a peripheral blood test.

Microenvironmental Traits of Classical Hodgkin's Lymphoma in Adolescents and Their Prognostic Impact

BACKGROUND

Classical Hodgkin's lymphoma (cHL) in adolescents between 15 and 18 years old shows a higher disease-related mortality, and the overall prognosis is worse than in both children and adults.

OBJECTIVES

We investigated the immune checkpoint inhibitors (ICPIs) therapeutic targets and specific T-regulatory and cytotoxic T-cell subsets in the subgroup of adolescent cHL patients, and we challenged their prognostic power.

METHODS

We retrieved formalin-fixed paraffin-embedded (FFPE) tissue of adolescent patients diagnosed with cHL and tested by immunohistochemistry the immune checkpoint molecules CTLA-4, LAG-3, PD-1, and PDL1 as well as the biological markers FOXP3 and CD8.

RESULTS

All the cases of our cohort expressed the immune checkpoint molecules CTLA-4, LAG-3, and PD-1 in microenvironment (ME), and the number of PD1+ cells was strongly associated with advanced disease, being higher in stage III/IV, indicating a possible role in the progression of cHL. A higher risk of recurrence and progression occurred in patients with lower amount of CD8+ microenvironmental T-cells at diagnosis (67.14 ± 27.23 vs. 42.86 ± 17.33 p = 0.032 and 65.59 ± 26.68 vs. 37 ± 17.45 p = 0.046, respectively).

CONCLUSIONS

We showed that microenvironment of cHL in adolescent patients is enriched with potential therapeutic targets of ICPI that may be considered for therapeutic applications. Furthermore, the presence of PD-1 expressing T-cells strongly relates to advanced stage disease and a low density of CD8+ T lymphocytes is associated with recurrence and progression of disease.

Liquid biopsy in cancer current: status, challenges and future prospects

Cancer has a high mortality rate across the globe, and tissue biopsy remains the gold standard for tumor diagnosis due to its high level of laboratory standardization, good consistency of results, relatively stable samples, and high accuracy of results. However, there are still many limitations and drawbacks in the application of tissue biopsy in tumor. The emergence of liquid biopsy provides new ideas for early diagnosis and prognosis of tumor. Compared with tissue biopsy, liquid biopsy has many advantages in the diagnosis and treatment of various types of cancer, including non-invasive, quickly and so on. Currently, the application of liquid biopsy in tumor detection has received widely attention. It is now undergoing rapid progress, and it holds significant potential for future applications. Around now, liquid biopsies encompass several components such as circulating tumor cells, circulating tumor DNA, exosomes, microRNA, circulating RNA, tumor platelets, and tumor endothelial cells. In addition, advances in the identification of liquid biopsy indicators have significantly enhanced the possibility of utilizing liquid biopsies in clinical settings. In this review, we will discuss the application, advantages and challenges of liquid biopsy in some common tumors from the perspective of diverse systems of tumors, and look forward to its future development prospects in the field of cancer diagnosis and treatment.

Impact of immunological aging on T cell-mediated therapies in older adults with multiple myeloma and lymphoma

The treatment landscape for lymphoma and multiple myeloma, which disproportionally affect older adults, has been transformed by the advent of T cell-mediated immunotherapies, including immune checkpoint inhibition, T cell-engaging bispecific antibodies, and chimeric antigen receptor (CAR) T cell therapy, during the last decade. These treatment modalities re-enable the patient's own immune system to combat malignant cells and offer the potential for sustained remissions and cure for various diseases.Age profoundly affects the physiological function of the immune system. The process of biological aging is largely driven by inflammatory signaling, which is reciprocally fueled by aging-related alterations of physiology and metabolism. In the T cell compartment, aging contributes to T cell senescence and exhaustion, increased abundance of terminally differentiated cells, a corresponding attrition in naïve T cell numbers, and a decrease in the breadth of the receptor repertoire. Furthermore, inflammatory signaling drives aging-related pathologies and contributes to frailty in older individuals. Thus, there is growing evidence of biological aging modulating the efficacy and toxicity of T cell-mediated immunotherapies.Here, we review the available evidence from biological and clinical studies focusing on the relationship between T cell-mediated treatment of hematologic malignancies and age. We discuss biological features potentially impacting clinical outcomes in various scenarios, and potential strategies to improve the safety and efficacy of immune checkpoint inhibitors, T cell-engaging bispecific antibodies, and CAR-T cell therapy in older patients.

CD28 co-stimulation: novel insights and applications in cancer immunotherapy

Substantial progress in understanding T cell signalling, particularly with respect to T cell co-receptors such as the co-stimulatory receptor CD28, has been made in recent years. This knowledge has been instrumental in the development of innovative immunotherapies for patients with cancer, including immune checkpoint blockade antibodies, adoptive cell therapies, tumour-targeted immunostimulatory antibodies, and immunostimulatory small-molecule drugs that regulate T cell activation. Following the failed clinical trial of a CD28 superagonist antibody in 2006, targeted CD28 agonism has re-emerged as a technologically viable and clinically promising strategy for cancer immunotherapy. In this Review, we explore recent insights into the molecular functions and regulation of CD28. We describe how CD28 is central to the success of current cancer immunotherapies and examine how new questions arising from studies of CD28 as a clinical target have enhanced our understanding of its biological role and may guide the development of future therapeutic strategies in oncology.

Cell-Free DNA in Hematologic Malignancies

Liquid biopsy techniques using cell-free DNA (cfDNA) play an increasingly important role in the characterization and surveillance of solid tumors. For blood cancers, molecular response assessment techniques using circulating malignant cells or bone marrow aspirates are well established in clinical care. However, cfDNA has an emerging role in hematology as well, with the opportunity for disease assessment and quantification independent of circulating disease burden or invasive biopsies. In this review, we discuss key technologies and clinical data for the utilization of cfDNA in lymphomas, myeloma, and leukemias.

MDM2 inhibitors in cancer immunotherapy: Current status and perspective

Murine double minute 2 (MDM2) plays an essential role in the cell cycle, apoptosis, DNA repair, and oncogene activation through p53-dependent and p53-independent signaling pathways. Several preclinical studies have shown that MDM2 is involved in tumor immune evasion. Therefore, MDM2-based regulation of tumor cell-intrinsic immunoregulation and the immune microenvironment has attracted increasing research attention. In recent years, immune checkpoint inhibitors targeting PD-1/PD-L1 have been widely used in the clinic. However, the effectiveness of a single agent is only approximately 20%-40%, which may be related to primary and secondary drug resistance caused by the dysregulation of oncoproteins. Here, we reviewed the role of MDM2 in regulating the immune microenvironment, tumor immune evasion, and hyperprogression during immunotherapy. In addition, we summarized preclinical and clinical findings on the use of MDM2 inhibitors in combination with immunotherapy in tumors with MDM2 overexpression or amplification. The results reveal that the inhibition of MDM2 could be a promising strategy for enhancing immunotherapy.

Intra-tumoral and peripheral blood TIGIT and PD-1 as immune biomarkers in nodular lymphocyte predominant Hodgkin lymphoma

In classical Hodgkin lymphoma (cHL), responsiveness to immune-checkpoint blockade (ICB) is associated with specific tumor microenvironment (TME) and peripheral blood features. The role of ICB in nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) is not established. To gain insights into its potential in NLPHL, we compared TME and peripheral blood signatures between HLs using an integrative multiomic analysis. A discovery/validation approach in 121 NLPHL and 114 cHL patients highlighted >2-fold enrichment in programmed cell death-1 (PD-1) and T-cell Ig and ITIM domain (TIGIT) gene expression for NLPHL versus cHL. Multiplex imaging showed marked increase in intra-tumoral protein expression of PD-1+ (and/or TIGIT+) CD4+ T-cells and PD-1+CD8+ T-cells in NLPHL compared to cHL. This included T-cells that rosetted with lymphocyte predominant (LP) and Hodgkin Reed-Sternberg (HRS) cells. In NLPHL, intra-tumoral PD-1+CD4+ T-cells frequently expressed TCF-1, a marker of heightened T-cell response to ICB. The peripheral blood signatures between HLs were also distinct, with higher levels of PD-1+TIGIT+ in TH1, TH2, and regulatory CD4+ T-cells in NLPHL versus cHL. Circulating PD-1+CD4+ had high levels of TCF-1. Notably, in both lymphomas, highly expanded populations of clonal TIGIT+PD-1+CD4+ and TIGIT+PD-1+CD8+ T-cells in the blood were also present in the TME, indicating that immune-checkpoint expressing T-cells circulated between intra-tumoral and blood compartments. In in vitro assays, ICB was capable of reducing rosette formation around LP and HRS cells, suggesting that disruption of rosetting may be a mechanism of action of ICB in HL. Overall, results indicate that further evaluation of ICB is warranted in NLPHL.

CD4+ T cells in antitumor immunity

Advances in cancer immunotherapy have transformed cancer care and realized unprecedented responses in many patients. The growing arsenal of novel therapeutics - including immune checkpoint inhibition (ICI), adoptive T cell therapies (ACTs), and cancer vaccines - reflects the success of cancer immunotherapy. The therapeutic benefits of these treatment modalities are generally attributed to the enhanced quantity and quality of antitumor CD8+ T cell responses. Nevertheless, CD4+ T cells are now recognized to play key roles in both the priming and effector phases of the antitumor immune response. In addition to providing T cell help through co-stimulation and cytokine production, CD4+ T cells can also possess cytotoxicity either directly on MHC class II-expressing tumor cells or to other cells within the tumor microenvironment (TME). The presence of specific populations of CD4+ T cells, and their intrinsic plasticity, within the TME can represent an important determinant of clinical response to immune checkpoint inhibitors, vaccines, and chimeric antigen receptor (CAR) T cell therapies. Understanding how the antitumor functions of specific CD4+ T cell types are induced while limiting their protumorigenic attributes will enable more successful immunotherapies.

Checkpoint inhibition enhances cell contacts between CD4+ T cells and Hodgkin-Reed-Sternberg cells of classic Hodgkin lymphoma

Although checkpoint molecules like CTLA-4 and PD1 have been described several years ago, checkpoint inhibitors such as nivolumab (an anti-PD-1 antibody) have only recently been used to treat classic Hodgkin lymphoma (cHL). Several studies have shown convincing therapeutic effects of nivolumab in cHL. However, the mechanism of action of nivolumab in cHL is not fully understood. The aim of this study was to monitor changes in cell motility and cell contacts after administration of nivolumab to an in vitro model of cHL as well as to native hyperplastic lymphoid tissue and native human tissue from cHL. In both tissue and in vitro, CD4+, CD8+, CD30+ and CD20+ cell velocities were unchanged after nivolumab incubation. In contrast, in primary cHL tissue, the duration of cell contacts between CD4+ T cells and Hodgkin-Reed-Sternberg cells was significantly increased after 5 hours of nivolumab treatment, and the number of contacts with HRS cells was also slightly increased for CD4+ T cells (not significant), suggesting that CD4+ T cells in particular contribute to the cytotoxicity observed as a result of nivolumab therapy. There was no change in the duration of cell contacts in the hyperplastic lymphoid tissue after nivolumab incubation. In conclusion, we show here for the first time by imaging of native lymphoma tissue an enhanced interaction of CD4+ T cells and Hodgkin-Reed-Sternberg cells in cHL after nivolumab administration.

Associations of Immune Checkpoint Predictive Biomarkers (MHC-I and MHC-II) with Clinical and Molecular Features in a Diverse Breast Cancer Cohort

PURPOSE

Immunotherapy (IO) in triple-negative breast cancer (TNBC) has improved survival outcomes, with promising improvements in pCR rates among early high-risk hormone receptor (HR)+/HER2- breast cancers. However, biomarkers are needed to select patients likely to benefit from IO. MHC-I and tumor-specific MHC-II (tsMHC-II) expression are candidate biomarkers for PD-(L)1 checkpoint inhibition but existing data from clinical trials included limited racial/ethnic diversity.

EXPERIMENTAL DESIGN

We performed multiplexed immunofluorescence assays in the Carolina Breast Cancer Study (CBCS; n = 1,628, 48% Black, 52% non-Black). Intrinsic subtype and P53 mutant-like status were identified using RNA-based multigene assays. We ranked participants based on tumoral MHC-I intensity (top 33% categorized as "MHC-Ihigh") and MHC-II+ (≥5% of tumor cells as tsMHC-II+). MHC-I/II were evaluated in association with clinicopathological features by race.

RESULTS

Black participants had higher frequency of TNBC (25% vs. 12.5%, P ≤ 0.001) and basal-like (30% vs. 14%, P ≤ 0.001) tumors overall, and higher frequency of basal-like (11% vs. 5.5%, P = 0.002) and TP53 mutant tumors (26% vs. 17%, P = 0.002) among HR+/HER2-. The frequency of tsMHC-II+ was higher in HR+/HER2- Black participants (7.9% vs. 4.9%, P = 0.04). Black participants also had higher frequency of MHC-Ihigh (38.7% vs. 28.2%, P < 0.001), which was significant among HR+/HER2- (28.2% vs. 22.1%, P = 0.02).

CONCLUSIONS

In this diverse study population, MHC-I and MHC-II tumor cell expression were more highly expressed in HR+/HER2- tumors from Black women, underscoring the importance of diverse and equitable enrollment in future IO trials.

Multiplexed Spatial Profiling of Hodgkin Reed-Sternberg Cell Neighborhoods in Classic Hodgkin Lymphoma

PURPOSE

Classic Hodgkin lymphoma (cHL) is a B-cell lymphoma that occurs primarily in young adults and, less frequently, in elderly individuals. A hallmark of cHL is the exceptional scarcity (1%-5%) of the malignant Hodgkin Reed-Sternberg (HRS) cells within a network of nonmalignant immune cells. Molecular determinants governing the relationship between HRS cells and their proximal microenvironment remain largely unknown.

EXPERIMENTAL DESIGN

We performed spatially resolved multiplexed protein imaging and transcriptomic sequencing to characterize HRS cell states, cellular neighborhoods, and gene expression signatures of 23.6 million cells from 36 newly diagnosed Epstein-Barr virus (EBV)-positive and EBV-negative cHL tumors.

RESULTS

We show that MHC-I expression on HRS cells is associated with immune-inflamed neighborhoods containing CD8+ T cells, MHC-II+ macrophages, and immune checkpoint expression (i.e., PD1 and VISTA). We identified spatial clustering of HRS cells, consistent with the syncytial variant of cHL, and its association with T-cell-excluded neighborhoods in a subset of EBV-negative tumors. Finally, a subset of both EBV-positive and EBV-negative tumors contained regulatory T-cell-high neighborhoods harboring HRS cells with augmented proliferative capacity.

CONCLUSIONS

Our study links HRS cell properties with distinct immunophenotypes and potential immune escape mechanisms in cHL.

Emerging immunotherapies in the Hodgkin lymphoma armamentarium

INTRODUCTION

Brentuximab vedotin and PD-1 inhibitors have improved outcomes for classic Hodgkin lymphoma (cHL), but better therapies are needed for patients who relapse after these agents. Based on an improved understanding of cHL biology, there is a robust pipeline of novel therapies in development. In this review, we highlight emerging immunotherapeutic agents and combinations for cHL.

AREAS COVERED

We review clinical trials of novel PD-1/PD-L1 inhibitors beyond FDA-approved agents, checkpoint inhibitors targeting CTLA-4, LAG-3, TIM-3, TIGIT, and CD47/SIRPα, PD-1 inhibitor combinations with immunomodulatory agents and epigenetic modifying therapies, antibody-drug conjugates, bispecific antibodies, and cellular therapies including anti-CD30 CAR-T and allogeneic NK cell therapy. We review the key safety and efficacy data from published phase 1-2 studies and highlight trials in progress, including the first phase 3 trial for PD-1 inhibitor-refractory cHL.

EXPERT OPINION

Many novel immunotherapies hold great promise in cHL. Rational combinations with existing agents and next-generation antibody and CAR-T constructs may improve response rates and durability. Identifying biomarkers of response to these immunotherapies and using more sensitive tools to assess response, such as circulating tumor DNA, may further inform treatment decisions and enable a precision medicine approach in the future.

Ovarian cancer ascites proteomic profile reflects metabolic changes during disease progression

Ovarian cancer (OC) patients develop ascites, an accumulation of ascitic fluid in the peritoneal cavity anda sign of tumour dissemination within the peritoneal cavity. This body fluid is under-researched, mainly regarding the ascites formed during tumour progression that have no diagnostic value and, therefore, are discarded. We performed a discovery proteomics study to identify new biomarkers in the ascites supernatant of OC patients. In this preliminary study, we analyzed a small amount of OC ascites to highlight the importance of not discarding such biological material during treatment, which could be valuable for OC management. Our findings reveal that OC malignant ascitic fluid (MAF) displays a proliferative environment that promotes the growth of OC cells that shift the metabolic pathway using alternative sources of nutrients, such as the cholesterol pathway. Also, OC ascites drained from patients during treatment showed an immunosuppressive environment, with up-regulation of proteins from the signaling pathways of IL-4 and IL-13 and down-regulation from the MHC-II. This preliminary study pinpointed a new protein (Transmembrane Protein 132A) in the OC context that deserves to be better explored in a more extensive cohort of patients' samples. The proteomic profile of MAF from OC patients provides a unique insight into the metabolic kinetics of cancer cells during disease progression, and this information can be used to develop more effective treatment strategies.

Higher tumor mutational burden and PD-L1 expression correlate with shorter survival in hematologic malignancies

Background

The prognostic implications of tumor mutational burden (TMB) and programmed death ligand 1 (PD-L1) expression are poorly studied in hematologic malignancies.

Objectives

This study aimed to better understand the characteristics and prognostic value of TMB and PD-1/PD-L1 in hematologic malignancies.

Design

This real-world study was conducted among patients with hematologic malignancies who had next-generation sequencing (NGS) (Foundation Medicine) at the University of California San Diego Moores Cancer Center (2014-2018).

Methods

TMB was measured by NGS. PD-L1 expression (tumor proportion score, TPS) was measured by immunohistochemistry (classified as high (⩾50%), low (1-49%), and negative (<1%)). Data was curated from the electronic medical records.

Results

In 388 evaluable patients, the most common diagnoses were B-cell non-Hodgkin lymphoma (NHL) (35%) and Philadelphia chromosome-negative myeloproliferative disorders (16%). Median TMB was 1.6 mutations/Mb (range, 0-46.83). Forty-eight patients (12%) had TMB ⩾10 mutations/Mb, 90% of which were B-cell or T-cell NHL. In 85 samples with available PD-L1 scores, 11 were high; 26, low; and 48, no tumor cell expression. PD-L1 TPS positive (⩾1%) was most common in T-cell NHL (7/9 (77%) cases) followed by B-cell NHL (21/51 (41%) cases). TMB ⩾4 mutations/Mb and PD-L1 score ⩾1% were significantly associated with shorter overall survival (OS) from diagnosis, with hazard ratio (HR) = 1.46 (p = 0.02, 95% confidence interval (CI) 1.05-2.03) and HR = 2.11 (p = 0.04, 95% CI 1.04-4.30), respectively; the relationship was more pronounced when PD-L1 ⩾50% versus <50% was used (HR = 2.80, p = 0.02, 95% CI 1.19-6.59). Higher TMB and higher PD-L1 positivity correlation were significant but weak (Pearson correlation coefficient R 2 = 0.04, p = 0.04).

Conclusion

TMB ⩾4 mutations/Mb and positive PD-L1 TPS are poor prognostic factors, correlating with shorter OS across hematologic malignancies.

Trial registration

ClinicalTrials.gov NCT02478931.

Personalized neoantigen vaccines as early intervention in untreated patients with lymphoplasmacytic lymphoma: a non-randomized phase 1 trial

Lymphoplasmacytic lymphoma (LPL) is an incurable low-grade lymphoma with no standard therapy. Nine asymptomatic patients treated with a first-in-human, neoantigen DNA vaccine experienced no dose limiting toxicities (primary endpoint, NCT01209871). All patients achieve stable disease or better, with one minor response, and median time to progression of 72+ months. Post-vaccine single-cell transcriptomics reveal dichotomous antitumor responses, with reduced tumor B-cells (tracked by unique B cell receptor) and their survival pathways, but no change in clonal plasma cells. Downregulation of human leukocyte antigen (HLA) class II molecules and paradoxical upregulation of insulin-like growth factor (IGF) by the latter suggest resistance mechanisms. Vaccine therapy activates and expands bone marrow T-cell clonotypes, and functional neoantigen-specific responses (secondary endpoint), but not co-inhibitory pathways or Treg, and reduces protumoral signaling by myeloid cells, suggesting favorable perturbation of the tumor immune microenvironment. Future strategies may require combinations of vaccines with agents targeting plasma cell subpopulations, or blockade of IGF-1 signaling or myeloid cell checkpoints.

Integrative transcriptome analysis reveals the molecular events underlying impaired T-cell responses in EGFR-mutant lung cancer

EGFR mutations are critical oncogenic drivers in lung adenocarcinoma (LUAD). However, the mechanisms by which they impact the tumor microenvironment (TME) and tumor immunity are unclear. Furthermore, the reasons underlying the poor response of EGFR-mutant (EGFR-MU) LUADs to immunotherapy with PD-1/PD-L1 inhibitors are unknown. Utilizing single-cell RNA (sc-RNA) and bulk RNA sequencing datasets, we conducted high-dimensional weighted gene coexpression network analysis to identify key genes and immune-related pathways contributing to the immunosuppressive TME. EGFR-MU cancer cells downregulated MHC class I genes to evade CD8+ cytotoxic T cells, expressed substantial levels of MHC class II molecules, and engaged with CD4+ regulatory T cells (Tregs). EGFR-MU tumors may recruit Tregs primarily through the CCL17/CCL22/CCR4 axis, leading to a Treg-enriched TME. High levels of MHC class II-positive cancer-associated fibroblasts and tumor endothelial cells were found within EGFR-MU tumors. Owing to the absence of costimulatory factors, they may inhibit rather than activate the tumor antigen-specific CD4+ T-cell response, contributing further to immune suppression. Multiplex immunohistochemistry analyses in a LUAD cohort confirmed increased expression of MHC class II molecules in cancer cells and fibroblasts in EGFR-MU tumors. Our research elucidates the highly immunosuppressive TME in EGFR-MU LUAD and suggests potential targets for effective immunotherapy.

Deciphering the interplay of HPV infection, MHC-II expression, and CXCL13+ CD4+ T cell activation in oropharyngeal cancer: implications for immunotherapy

BACKGROUND

Human papillomavirus (HPV) infection has become an important etiological driver of oropharyngeal squamous cell carcinoma (OPSCC), leading to unique tumor characteristics. However, the interplay between HPV-associated tumor cells and tumor microenvironment (TME) remains an enigma.

METHODS

We performed a single-cell RNA-sequencing (scRNA-seq) on HPV-positive (HPV+) and HPV-negative (HPV‒) OPSCC tumors, each for three samples, and one normal tonsil tissue. Ex vivo validation assays including immunofluorescence staining, cell line co-culture, and flow cytometry analysis were used to test specific subtypes of HPV+ tumor cells and their communications with T cells.

RESULTS

Through a comprehensive single-cell transcriptome analysis, we uncover the distinct transcriptional signatures between HPV+ and HPV‒ OPSCC. Specifically, HPV+ OPSCC tumor cells manifest an enhanced interferon response and elevated expression of the major histocompatibility complex II (MHC-II), potentially bolstering tumor recognition and immune response. Furthermore, we identify a CXCL13+CD4+ T cell subset that exhibits dual features of both follicular and pro-inflammatory helper T cells. Noteworthily, HPV+ OPSCC tumor cells embrace extensive intercellular communications with CXCL13+CD4+ T cells. Interaction with HPV+ OPSCC tumor cells amplifies CXCL13 and IFNγ release in CD4+T cells, fostering a pro-inflammatory TME. Additionally, HPV+ tumor cells expressing high MHC-II and CXCL13+CD4+ T cell prevalence are indicative of favorable overall survival rates in OPSCC patients.

CONCLUSIONS

Together, our study underscores a synergistic inflammatory immune response orchestrated by highly immunogenic tumor cells and CXCL13+CD4+ T cells in HPV+ OPSCC, offering useful insights into strategy development for patient stratification and effective immunotherapy in OPSCC.

Interrogating the roles of lymph node metastasis in systemic immune surveillance

Lymph nodes (LNs) are principal orchestrators of the adaptive immune response, yet in the context of malignancy, they are typically the first sites of metastasis. When tumors spread to LNs, they alter the immune repertoire, ultimately reconditioning it in a manner that suppresses anti-tumor immunity and promotes further metastatic dissemination. Conversely, activation of anti-tumor immunity within LNs is essential for immunotherapy, suggesting clinical approaches to radiotherapy in LNs and lymphadenectomy may need to be reconsidered in the context of immune checkpoint blockade (ICB). Herein, we discuss our understanding of the immune remodeling that coincides with LN metastasis as well as recent clinical studies exploring neoadjuvant immunotherapy and the roles of LNs in treatment of solid organ malignancies.

Timing of whole genome duplication is associated with tumor-specific MHC-II depletion in serous ovarian cancer

Whole genome duplication is frequently observed in cancer, and its prevalence in our prior analysis of end-stage, homologous recombination deficient high grade serous ovarian cancer (almost 80% of samples) supports the notion that whole genome duplication provides a fitness advantage under the selection pressure of therapy. Here, we therefore aim to identify potential therapeutic vulnerabilities in primary high grade serous ovarian cancer with whole genome duplication by assessing differentially expressed genes and pathways in 79 samples. We observe that MHC-II expression is lowest in tumors which have acquired whole genome duplication early in tumor evolution, and further demonstrate that reduced MHC-II expression occurs in subsets of tumor cells rather than in canonical antigen-presenting cells. Early whole genome duplication is also associated with worse patient survival outcomes. Our results suggest an association between the timing of whole genome duplication, MHC-II expression and clinical outcome in high grade serous ovarian cancer that warrants further investigation for therapeutic targeting.

Single-cell analysis identifies PLK1 as a driver of immunosuppressive tumor microenvironment in LUAD

PLK1 (Polo-like kinase 1) plays a critical role in the progression of lung adenocarcinoma (LUAD). Recent studies have unveiled that targeting PLK1 improves the efficacy of immunotherapy, highlighting its important role in the regulation of tumor immunity. Nevertheless, our understanding of the intricate interplay between PLK1 and the tumor microenvironment (TME) remains incomplete. Here, using genetically engineered mouse model and single-cell RNA-seq analysis, we report that PLK1 promotes an immunosuppressive TME in LUAD, characterized with enhanced M2 polarization of tumor associated macrophages (TAM) and dampened antigen presentation process. Mechanistically, elevated PLK1 coincides with increased secretion of CXCL2 cytokine, which promotes M2 polarization of TAM and diminishes expression of class II major histocompatibility complex (MHC-II) in professional antigen-presenting cells. Furthermore, PLK1 negatively regulates MHC-II expression in cancer cells, which has been shown to be associated with compromised tumor immunity and unfavorable patient outcomes. Taken together, our results reveal PLK1 as a novel modulator of TME in LUAD and provide possible therapeutic interventions.

Human leukocyte antigen (HLA) class I expression on Hodgkin-Reed-Sternberg cells is an EBV-independent major determinant of microenvironment composition in classic Hodgkin lymphoma

Hodgkin-Reed-Sternberg cells (HRSCs) in classic Hodgkin Lymphoma (HL) frequently lack expression of human leukocyte antigen class I (HLA-I), considered to hamper activation of cytotoxic T cells in the tumor microenvironment (TME). Here, we demonstrate HLA-I expression on HRSCs to be a strong determinant of TME composition whereas expression of HLA-II was associated with only minor differential gene expression in the TME. In HLA-I-positive HL the HRSC content and expression of CCL17/TARC in HRSCs are low, independent of the presence of Epstein-Barr virus in HRSCs. Additionally, HLA-I-positive HL shows a high content of CD8+ cytotoxic T cells. However, an increased expression of the inhibitory immune checkpoint LAG3 on CD8+ T cells in close proximity to HRSCs is observed. Suggesting interference with cytotoxic activity, we observed an absence of clonally expanded T cells in the TME. While HLA-I-positive HL is not associated with an unfavorable clinical course in our cohorts, they share features with the recently described H2 subtype of HL. Given the major differences in TME composition, immune checkpoint inhibitors may differ in their mechanism of action in HLA-I-positive compared to HLA-I-negative HL.

Molecular biomarkers in classic Hodgkin lymphoma

Classic Hodgkin lymphoma is a unique B-cell derived malignancy featuring rare malignant Hodgkin and Reed Sternberg (HRS) cells that are embedded in a quantitively dominant tumor microenvironment (TME). Treatment of classic Hodgkin lymphoma has significantly evolved in the past decade with improving treatment outcomes for newly diagnosed patients and the minority of patients suffering from disease progression. However, the burden of toxicity and treatment-related long-term sequelae remains high in a typically young patient population. This highlights the need for better molecular biomarkers aiding in risk-adapted treatment strategies and predicting response to an increasing number of available treatments that now prominently involve multiple immunotherapy options. Here, we review modern molecular biomarker approaches that reflect both the biology of the malignant HRS cells and cellular components in the TME, while holding the promise to improve diagnostic frameworks for clinical decision-making and be feasible in clinical trials and routine practice. In particular, technical advances in sequencing and analytic pipelines using liquid biopsies, as well as deep phenotypic characterization of tissue architecture at single-cell resolution, have emerged as the new frontier of biomarker development awaiting further validation and implementation in routine diagnostic procedures.

Improved Immunotherapy Outcomes via Cuproptosis Upregulation of HLA-DRA Expression: Promoting the Aggregation of CD4+ and CD8+T Lymphocytes in Clear Cell Renal Cell Carcinoma

Immunotherapy has shown promising clinical results in clear cell renal cell carcinoma (ccRCC), but low clinical target response rates due to dysfunction of the major histocompatibility complex (MHC) and an inhibitory tumor immune microenvironment (TIME) have largely limited the associated clinical benefits. In the present study, we explored the feasibility of enhancing tumor-specific-MHC-II-HLA-DRA expression, counteracting the TIME's suppressive effects, thereby improving the sensitivity of immune checkpoint inhibitor (ICI) therapy from the standpoint of cuproptosis. Immunohistochemical staining and in vitro experiments validated the expression of HLA-DRA in ccRCC and its positive impact on ICI therapy. Subsequently, we observed that cuproptosis upregulated HLA-DRA expression in a dose-dependent manner, further confirming the link between cuproptosis and HLA-DRA. In vivo experiments showed that cuproptosis increased the sensitivity to ICI treatment, and implementing cuproptosis alongside anti-PD-1 treatment curtailed tumor growth. Mechanistically, cuproptosis upregulates HLA-DRA expression at the transcriptional level in a dose-dependent manner by inducing the production of reactive oxygen species; high levels of HLA-DRA promote the expression of chemokines CCL5, CXCL9, and CXCL10 in the TIME, inhibiting the development of a pro-tumor microenvironment by promoting the infiltration of CD4+T and CD8+T cells, thereby synergizing ICI therapy and exerting anti-tumor effects. Taken together, this work highlights the role of cuproptosis in mediating TIME remodeling and synergistic immunotherapy, providing new evidence that cuproptosis can evoke effective anti-tumor immune responses.

The biology of classical Hodgkin lymphoma

Classical Hodgkin lymphoma (cHL) is distinguished by several important biological characteristics. The presence of Hodgkin Reed Sternberg (HRS) cells is a defining feature of this disease. The tumor microenvironment with relatively few HRS cells in an expansive infiltrate of immune cells is another key feature. Numerous cell-cell mediated interactions and a plethora of cytokines in the tumor microenvironment collectively work to promote HRS cell growth and survival. Aberrancy and constitutive activation of core signal transduction pathways are a hallmark trait of cHL. Genetic lesions contribute to these dysregulated pathways and evasion of the immune system through a variety of mechanisms is another notable feature of cHL. While substantial elucidation of the biology of cHL has enabled advancements in therapy, increased understanding in the future of additional mechanisms driving cHL may lead to new treatment opportunities.

Integrative analysis of single-cell and bulk RNA sequencing unveils a machine learning-based pan-cancer major histocompatibility complex-related signature for predicting immunotherapy efficacy

Major histocompatibility complex (MHC) could serve as a potential biomarker for tumor immunotherapy, however, it is not yet known whether MHC could distinguish potential beneficiaries. Single-cell RNA sequencing datasets derived from patients with immunotherapy were collected to elucidate the association between MHC and immunotherapy response. A novel MHCsig was developed and validated using large-scale pan-cancer data, including The Cancer Genome Atlas and immunotherapy cohorts. The therapeutic value of MHCsig was further explored using 17 CRISPR/Cas9 datasets. MHC-related genes were associated with drug resistance and MHCsig was significantly and positively associated with immunotherapy response and total mutational burden. Remarkably, MHCsig significantly enriched 6% top-ranked genes, which were potential therapeutic targets. Moreover, we generated Hub-MHCsig, which was associated with survival and disease-special survival of pan-cancer, especially low-grade glioma. This result was also confirmed in cell lines and in our own clinical cohort. Later low-grade glioma-related Hub-MHCsig was established and the regulatory network was constructed. We provided conclusive clinical evidence regarding the association between MHCsig and immunotherapy response. We developed MHCsig, which could effectively predict the benefits of immunotherapy for multiple tumors. Further exploration of MHCsig revealed some potential therapeutic targets and regulatory networks.

Upregulation of HLA-II related to LAG-3+CD4+ T cell infiltration is associated with patient outcome in human glioblastoma

Glioblastoma (GBM) is the most common malignant diffuse glioma of the brain. Although immunotherapy with immune checkpoint inhibitors (ICIs), such as programmed cell death protein (PD)-1/PD ligand-1 inhibitors, has revolutionized the treatment of several cancers, the clinical benefit in GBM patients has been limited. Lymphocyte-activation gene 3 (LAG-3) binding to human leukocyte antigen-II (HLA-II) plays an essential role in triggering CD4+ T cell exhaustion and could interfere with the efficiency of anti-PD-1 treatment; however, the value of LAG-3-HLA-II interactions in ICI immunotherapy for GBM patients has not yet been analyzed. Therefore, we aimed to investigate the expression and regulation of HLA-II in human GBM samples and the correlation with LAG-3+CD4+ T cell infiltration. Human leukocyte antigen-II was highly expressed in GBM and correlated with increased LAG-3+CD4+ T cell infiltration in the stroma. Additionally, HLA-IIHighLAG-3High was associated with worse patient survival. Increased interleukin-10 (IL-10) expression was observed in GBM, which was correlated with high levels of HLA-II and LAG-3+ T cell infiltration in stroma. HLA-IIHighIL-10High GBM associated with LAG-3+ T cells infiltration synergistically showed shorter overall survival in patients. Combined anti-LAG-3 and anti-IL-10 treatment inhibited tumor growth in a mouse brain GL261 tumor model. In vitro, CD68+ macrophages upregulated HLA-II expression in GBM cells through tumor necrosis factor-α (TNF-α). Blocking TNF-α-dependent inflammation inhibited tumor growth in a mouse GBM model. In summary, T cell-tumor cell interactions, such as LAG-3-HLA-II, could confer an immunosuppressive environment in human GBM, leading to poor prognosis in patients. Therefore, targeting the LAG-3-HLA-II interaction could be beneficial in ICI immunotherapy to improve the clinical outcome of GBM patients.

Immune checkpoint inhibitors in advanced and relapsed/refractory Hodgkin lymphoma: current applications and future prospects

Classic Hodgkin lymphoma (cHL) treatment paradigms are undergoing a shift with the integration of immune checkpoint inhibitors (ICIs) into both first-line and relapsed/refractory (R/R) regimens. In first-line therapy, the synergy between ICIs and chemotherapy may surpass the previous standards of ABVD and BV-AVD established by landmark trials including RATHL and ECHELON-1. In R/R disease, the combination of ICIs with chemotherapy has begun to challenge the paradigm of chemotherapy as a bridge to consolidative autologous stem cell transplantation. The clinical advances heralded by ICI offer unique challenges to management. ICI treatment and the associated inflammatory response can make the traditional timing and modalities of treatment response assessment difficult to interpret. In contrast to ABVD and BV-AVD, pembrolizumab-AVD results in PET2 positivity rates that are higher and less predictive of treatment response even when ultimate outcomes may be superior. This suggests that the predictive value of PET2 may be less reliable in the ICI era, prompting a reevaluation of response assessment strategies. Looking forward, circulating tumor DNA (ctDNA) may be a promising tool in response-adapted therapy. Its potential to complement or even supersede PET scans in predicting response to ICIs represents a critical advancement. The integration of ctDNA analysis holds the promise of refining response-adapted approaches and enhancing precision in therapeutic decision-making for patients with cHL. This review navigates the evolving landscape of cHL therapy, emphasizing the paradigmatic shift brought about by ICIs. This article explores the impact of combining ICIs with chemotherapy in both relapsed/refractory and first-line settings, scrutinizes the challenges posed to response-adapted therapy by ICIs, and highlights the potential role of ctDNA as an adjunct in refining response-adapted strategies for cHL.

Single-cell transcriptome sequencing provides insight into multiple chemotherapy resistance in a patient with refractory DLBCL: a case report

Relapsed and refractory diffuse large B-cell lymphoma (DLBCL) is associated with poor prognosis. As such, a comprehensive analysis of intratumoral components, intratumoral heterogeneity, and the immune microenvironment is essential to elucidate the mechanisms driving the progression of DLBCL and to develop new therapeutics. Here, we used single-cell transcriptome sequencing and conventional bulk next-generation sequencing (NGS) to understand the composite tumor landscape of a single patient who had experienced multiple tumor recurrences following several chemotherapy treatments. NGS revealed several key somatic mutations that are known to contribute to drug resistance. Based on gene expression profiles at the single-cell level, we identified four clusters of malignant B cells with distinct transcriptional signatures, showing high intra-tumoral heterogeneity. Among them, heterogeneity was reflected in activating several key pathways, human leukocyte antigen (HLA)-related molecules' expression, and key oncogenes, which may lead to multi-drug resistance. In addition, FOXP3+ regulatory CD4+ T cells and exhausted cytotoxic CD8+ T cells were identified, accounted for a significant proportion, and showed highly immunosuppressive properties. Finally, cell communication analysis indicated complex interactions between malignant B cells and T cells. In conclusion, this case report demonstrates the value of single-cell RNA sequencing for visualizing the tumor microenvironment and identifying potential therapeutic targets in a patient with treatment-refractory DLBCL. The combination of NGS and single-cell RNA sequencing may facilitate clinical decision-making and drug selection in challenging DLBCL cases.

Epstein-Barr Virus Orchestrates Spatial Reorganization and Immunomodulation within the Classic Hodgkin Lymphoma Tumor Microenvironment

Classic Hodgkin Lymphoma (cHL) is a tumor composed of rare malignant Hodgkin and Reed-Sternberg (HRS) cells nested within a T-cell rich inflammatory immune infiltrate. cHL is associated with Epstein-Barr Virus (EBV) in 25% of cases. The specific contributions of EBV to the pathogenesis of cHL remain largely unknown, in part due to technical barriers in dissecting the tumor microenvironment (TME) in high detail. Herein, we applied multiplexed ion beam imaging (MIBI) spatial pro-teomics on 6 EBV-positive and 14 EBV-negative cHL samples. We identify key TME features that distinguish between EBV-positive and EBV-negative cHL, including the relative predominance of memory CD8 T cells and increased T-cell dysfunction as a function of spatial proximity to HRS cells. Building upon a larger multi-institutional cohort of 22 EBV-positive and 24 EBV-negative cHL samples, we orthogonally validated our findings through a spatial multi-omics approach, coupling whole transcriptome capture with antibody-defined cell types for tu-mor and T-cell populations within the cHL TME. We delineate contrasting transcriptomic immunological signatures between EBV-positive and EBV-negative cases that differently impact HRS cell proliferation, tumor-immune interactions, and mecha-nisms of T-cell dysregulation and dysfunction. Our multi-modal framework enabled a comprehensive dissection of EBV-linked reorganization and immune evasion within the cHL TME, and highlighted the need to elucidate the cellular and molecular fac-tors of virus-associated tumors, with potential for targeted therapeutic strategies.

T-cell States, Repertoire, and Function in Classical Hodgkin Lymphoma Revealed through Single-Cell Analyses

The classical Hodgkin lymphoma (cHL) environment is comprised of a dense and complex immune cell infiltrate interspersed with rare malignant Hodgkin-Reed-Sternberg (HRS) cells. HRS cells are actively surveilled by endogenous T cells, but data linking phenotypic and functional T-cell states with clonality at the single-cell level in cHL is lacking. To address this knowledge gap, we performed paired single-cell RNA and T-cell receptor sequencing on 14 cHL and 5 reactive lymphoid tissue specimens. Conventional CD4+ T cells dominated the cHL landscape. However, recurrent clonal expansion within effector and exhausted CD8+ T-cell and regulatory T-cell clusters was uniquely observed in cHL specimens. Multiplex flow cytometric analysis revealed that most lymphoma-resident T cells produced effector cytokines upon ex vivo restimulation, arguing against a profound dysfunctional T-cell state in cHL. Our results raise new questions about the nature of T cells that mediate the antilymphoma response following programmed cell death protein 1 (PD-1) blockade therapy in cHL.

Predictive and prognostic molecular biomarkers in lymphomas

Recent advances in molecular diagnostics have markedly expanded our understanding of the genetic underpinnings of lymphomas and catalysed a transformation in not just how we classify lymphomas, but also how we treat, target, and monitor affected patients. Reflecting these advances, the World Health Organization Classification, International Consensus Classification, and National Comprehensive Cancer Network guidelines were recently updated to better integrate these molecular insights into clinical practice. We summarise here the molecular biomarkers of lymphomas with an emphasis on biomarkers that have well-supported prognostic and predictive utility, as well as emerging biomarkers that show promise for clinical practice. These biomarkers include: (1) diagnostic entity-defining genetic abnormalities [e.g., B-cell acute lymphoblastic leukaemia (B-ALL) with KMT2A rearrangement]; (2) molecular alterations that guide patients' prognoses (e.g., TP53 loss frequently conferring worse prognosis); (3) mutations that serve as the targets of, and often a source of acquired resistance to, small molecular inhibitors (e.g., ABL1 tyrosine kinase inhibitors for B-ALL BCR::ABL1, hindered by ABL1 kinase domain resistance mutations); (4) the growing incorporation of molecular measurable residual disease (MRD) in the management of lymphoma patients (e.g., molecular complete response and sequencing MRD-negative criteria in multiple myeloma). Altogether, our review spans the spectrum of lymphoma types, from the genetically defined subclasses of precursor B-cell lymphomas to the highly heterogeneous categories of small and large cell mature B-cell lymphomas, Hodgkin lymphomas, plasma cell neoplasms, and T/NK-cell lymphomas, and provides an expansive summary of our current understanding of their molecular pathology.

Immune and stromal transcriptional patterns that influence the outcome of classic Hodgkin lymphoma

Classic Hodgkin lymphoma (cHL) is characterized by a rich immune microenvironment as the main tumor component. It involves a broad range of cell populations, which are largely unexplored, even though they are known to be essential for growth and survival of Hodgkin and Reed-Sternberg cells. We profiled the gene expression of 25 FFPE cHL samples using NanoString technology and resolved their microenvironment compositions using cell-deconvolution tools, thereby generating patient-specific signatures. The results confirm individual immune fingerprints and recognize multiple clusters enriched in refractory patients, highlighting the relevance of: (1) the composition of immune cells and their functional status, including myeloid cell populations (M1-like, M2-like, plasmacytoid dendritic cells, myeloid-derived suppressor cells, etc.), CD4-positive T cells (exhausted, regulatory, Th17, etc.), cytotoxic CD8 T and natural killer cells; (2) the balance between inflammatory signatures (such as IL6, TNF, IFN-γ/TGF-β) and MHC-I/MHC-II molecules; and (3) several cells, pathways and genes related to the stroma and extracellular matrix remodeling. A validation model combining relevant immune and stromal signatures identifies patients with unfavorable outcomes, producing the same results in an independent cHL series. Our results reveal the heterogeneity of immune responses among patients, confirm previous findings, and identify new functional phenotypes of prognostic and predictive utility.

Antibody based therapies in Hodgkin lymphoma

Multimodality treatment approaches, with systemic therapies at their core, have made Hodgkin Lymphoma a highly curable cancer. Unmet needs remain. Resistance to therapy manifested by refractory and relapsed disease, and treatment related short- and long-term morbidity are the key challenges. Patient outcomes have improved in the recent past with the advent of novel therapies and are borne out of a better understanding of the disease biology and translational medicine. Antibody based therapies, more broadly immunotherapies, are leading the change in the way we treat this disease. This review looks at the tumor antigen-directed immunotherapies, and immune checkpoint inhibitors that are attempting to overcome the unmet challenges.

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.

Polycomb repressor complex 2 suppresses interferon-responsive MHC-II expression in melanoma cells and is associated with anti-PD-1 resistance

BACKGROUND

Despite the remarkable success of immunotherapy in treating melanoma, understanding of the underlying mechanisms of resistance remains limited. Emerging evidence suggests that upregulation of tumor-specific major histocompatibility complex-II (tsMHC-II) serves as a predictive marker for the response to anti-programmed death-1 (PD-1)/programmed death ligand 1 (PD-L1) therapy in various cancer types. The genetic and epigenetic pathways modulating tsMHC-II expression remain incompletely characterized. Here, we provide evidence that polycomb repressive complex 2 (PRC2)/EZH2 signaling and resulting H3K27 hypermethylation suppresses tsMHC-II.

METHODS

RNA sequencing data from tumor biopsies from patients with cutaneous melanoma treated with or without anti-PD-1, targeted inhibition assays, and assays for transposase-accessible chromatin with sequencing were used to observe the relationship between EZH2 inhibition and interferon (IFN)-γ inducibility within the MHC-II pathway.

RESULTS

We find that increased EZH2 pathway messenger RNA (mRNA) expression correlates with reduced mRNA expression of both presentation and T-cell genes. Notably, targeted inhibition assays revealed that inhibition of EZH2 influences the expression dynamics and inducibility of the MHC-II pathway following IFN-γ stimulation. Additionally, our analysis of patients with metastatic melanoma revealed a significant inverse association between PRC2-related gene expression and response to anti-PD-1 therapy.

CONCLUSIONS

Collectively, our findings demonstrate that EZH2 inhibition leads to enhanced MHC-II expression potentially resulting from improved chromatin accessibility at CIITA, the master regulator of MHC-II. These insights shed light on the molecular mechanisms involved in tsMHC-II suppression and highlight the potential of targeting EZH2 as a therapeutic strategy to improve immunotherapy efficacy.

Potential Associations between Vascular Biology and Hodgkin's Lymphoma: An Overview

Hodgkin's lymphoma (HL) is a lymphatic neoplasm typically found in the cervical lymph nodes. The disease is multifactorial, and in recent years, the relationships between various vascular molecules have been explored in the field of vascular biology. The connection between vascular biology and HL is intricate and the roles of several pathways remain unclear. This review summarizes the cellular and molecular relationships between vascular biology and HL. Proteins associated with various functions in vascular biology, including cytokines (TNF-α, IL-1, IL-13, and IL-21), chemokines (CXCL10, CXCL12, and CCL21), adhesion molecules (ELAM-1/VCAM-1), and growth factors (BDNF/NT-3, platelet-derived growth factor receptor-α), have been linked to tumor activity. Notable tumor activities include the induction of paracrine activation of NF-kB-dependent pathways, upregulation of adhesion molecule regulation, genome amplification, and effective loss of antigen presentation mediated by MHC-II. Preclinical study models, primarily those using cell culture, have been optimized for HL. Animal models, particularly mice, are also used as alternatives to complex biological systems, with studies primarily focusing on the physiopathogenic evaluation of the disease. These biomolecules warrant further study because they may shed light on obscure pathways and serve as targets for prevention and/or treatment interventions.

The pathobiology of select adolescent young adult lymphomas

Lymphoid cancers are among the most frequent cancers diagnosed in adolescents and young adults (AYA), ranging from approximately 30%-35% of cancer diagnoses in adolescent patients (age 10-19) to approximately 10% in patients aged 30-39 years. Moreover, the specific distribution of lymphoid cancer types varies by age with substantial shifts in the subtype distributions between pediatric, AYA, adult, and older adult patients. Currently, biology studies specific to AYA lymphomas are rare and therefore insight into age-related pathogenesis is incomplete. This review focuses on the paradigmatic epidemiology and pathogenesis of select lymphomas, occurring in the AYA patient population. With the example of posttransplant lymphoproliferative disorders, nodular lymphocyte-predominant Hodgkin lymphoma, follicular lymphoma (incl. pediatric-type follicular lymphoma), and mediastinal lymphomas (incl. classic Hodgkin lymphoma, primary mediastinal large B cell lymphoma and mediastinal gray zone lymphoma), we here illustrate the current state-of-the-art in lymphoma classification, recent molecular insights including genomics, and translational opportunities. To improve outcome and quality of life, international collaboration in consortia dedicated to AYA lymphoma is needed to overcome challenges related to siloed biospecimens and data collections as well as to develop studies designed specifically for this unique population.

Characterization of the tumor microenvironment and identification of spatially predictive biomarkers associated with beneficial neoadjuvant chemoradiotherapy in locally advanced rectal cancer

Neoadjuvant chemoradiotherapy (nCRT) has become the standard treatment for patients with locally advanced rectal cancer (LARC). However, 20-40% of patients with LARC show little to no response to nCRT. Thus, comprehensively understanding the tumor microenvironment (TME), which might influence therapeutic efficacy, and identifying robust predictive biomarkers is urgently needed. Pre-treatment tumor biopsy specimens from patients with LARC were evaluated in detail through digital spatial profiling (DSP), public RNA sequencing datasets, and multiplex immunofluorescence (mIF). DSP analysis revealed distinct characteristics of the tumor stroma compared to the normal stroma and tumor compartments. We identified high levels of human leukocyte antigen-DR/major histocompatibility complex class II (HLA-DR/MHC-II) in the tumor compartment and B cells in the stroma as potential spatial predictors of nCRT efficacy in the Discovery cohort. Public datasets validated their predictive capacity for clinical outcomes. Using mIF in an independent nCRT cohort and/or the total cohort, we validated that a high density of HLA-DR/MHC-II+ cells in the tumor and CD20 + B cells in the stroma was associated with nCRT efficacy (all p ≤ 0.021). Spatial profiling successfully characterized the LARC TME and identified robust biomarkers with the potential to accurately predict nCRT response. These findings have important implications for individualized therapy.

Identification an innovative classification and nomogram for predicting the prognosis of thyroid carcinoma patients and providing therapeutic schedules

BACKGROUND

Thyroid carcinoma (THCA) represents a prevalent form of cancer globally, with its incidence demonstrating an upward trend in recent years. Accumulating evidence has indicated that programmed cell death (PCD) patterns exert a vital influence on tumor progression. Nevertheless, the association between PCD and the prognosis of patients with papillary thyroid carcinoma remains to be elucidated. The current study endeavors to examine the link between PCD and the prognosis of thyroid cancer while concurrently developing a prognostic index based on PCD genes.

MATERIALS AND METHODS

Programmed cell death patterns were employed to construct the model and define clusters. Gene expression profile genomics and clinical data pertaining to 568 patients with thyroid cancer were sourced from the TCGA database. In addition, single-cell transcriptome data GSE184362 were procured from the Gene Expression Omnibus (GEO) database for subsequent analysis.

RESULTS

The study harnessed six machine learning algorithms to create a programmed cell death signature (PCDS). Ultimately, the model developed via SVM was chosen as the optimal model, boasting the highest C-index. Moreover, the application of non-negative matrix factorization (NMF) led to the identification of two molecular subtypes of THCA, each characterized by distinct vital biological processes and drug sensitivities. The investigation revealed that PCDS is linked to chemokines, interleukins, interferons, and checkpoint genes, as well as pivotal components of the tumor microenvironment, as determined through a comprehensive analysis of bulk and single-cell transcriptomes. Patients with THCA and elevated PCDS values are more inclined to exhibit resistance to conventional chemotherapy regimens, yet may display heightened responsiveness to targeted therapeutic agents. Finally, we established a nomogram model based on multivariable cox and logistic regression analyses to predict the overall survival of THCA patients.

CONCLUSION

This research sheds new light on the role of programmed cell death (PCD) patterns in THCA. By conducting an in-depth analysis of various cell death patterns, a novel PCD model has been devised, capable of accurately predicting the clinical prognosis and drug sensitivity of patients with THCA.

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.