Tumor Immune Microenvironment in Lymphoma: Focus on Epigenetics

[Progression and application of circulating tumor DNA in lymphoma]

Lymphomas are a highly heterogeneous group of tumors that are classified into several subtypes. The gold standard method for the molecular profiling of lymphoma is based on invasive lymph node or tissue biopsy. However, this method cannot accurately capture spatial tumor heterogeneity in each patient as well as systemic tumor invasion and tumor burden. Circulating tumor DNA (ctDNA) is an emerging and highly versatile biomarker that overcomes the basic limitations of imaging scanning and tissue biopsy; has the characteristics of being simple, rapid, and non-invasive; and has good specificity and high sensitivity. ctDNA testing has been applied to a variety of subtypes of lymphoma and has been used for somatic mutation genotyping, efficacy monitoring during treatment, detection of minimal residual disease, and the prediction of survival, which may help clinicians make better clinical decisions in the diagnosis and treatment of lymphoma patients. Furthermore, this study also aims to review the different methods of ctDNA analysis and describe the specific applications of ctDNA in different lymphoma subtypes.

T Cells Spatially Regulate B Cell Receptor Signaling in Lymphomas through H3K9me3 Modifications

Activated B cell-like diffuse large B-cell lymphoma (ABC-DLBCL) is a subtype associated with poor survival outcomes. Despite identifying therapeutic targets through molecular characterization, targeted therapies have limited success. New strategies using immune-competent tissue models are needed to understand how DLBCL cells evade treatment. Here, synthetic hydrogel-based lymphoma organoids are used to demonstrate how signals in the lymphoid tumor microenvironment (Ly-TME) can alter B cell receptor (BCR) signaling and specific histone modifications, tri-methylation of histone 3 at lysine 9 (H3K9me3), dampening the effects of BCR pathway inhibition. Using imaging modalities, T cells increase DNA methyltransferase 3A expression and cytoskeleton formation in proximal ABC-DLBCL cells, regulated by H3K9me3. Expansion microscopy on lymphoma organoids reveals T cells increase the size and quantity of segregated H3K9me3 clusters in ABC-DLBCL cells. Findings suggest the re-organization of higher-order chromatin structures that may contribute to evasion or resistance to therapy via the emergence of novel transcriptional states. Treating ABC-DLBCL cells with a G9α histone methyltransferase inhibitor reverses T cell-mediated modulation of H3K9me3 and overcomes T cell-mediated attenuation of treatment response to BCR pathway inhibition. This study emphasizes the Ly-TME's role in altering DLBCL fate and suggests targeting aberrant signaling and microenvironmental cross-talk that can benefit high-risk patients.

Exploring risk factors for autoimmune diseases complicated by non-hodgkin lymphoma through regulatory T cell immune-related traits: a Mendelian randomization study

Background

The effect of immune cells on autoimmune diseases (ADs) complicated by non-Hodgkin lymphoma (NHL) has been widely recognized, but a causal relationship between regulatory T cell (Treg) immune traits and ADs complicated by NHL remains debated.

Methods

Aggregate data for 84 Treg-related immune traits were downloaded from the Genome-Wide Association Study (GWAS) catalog, and GWAS data for diffuse large B-cell lymphoma (DLBCL; n=315243), follicular lymphoma (FL; n=325831), sjögren's syndrome (SS; n=402090), rheumatoid arthritis (RA; n=276465), dermatopolymyositis (DM; n=311640), psoriasis (n=407876), atopic dermatitis (AD; n=382254), ulcerative colitis (UC; n=411317), crohn's disease(CD; n=411973) and systemic lupus erythematosus (SLE; n=307587) were downloaded from the FinnGen database. The inverse variance weighting (IVW) method was mainly used to infer any causal association between Treg-related immune traits and DLBCL, FL, SS, DM, RA, Psoriasis, AD, UC, CD and SLE, supplemented by MR-Egger, weighted median, simple mode, and weighted mode. Moreover, we performed sensitivity analyses to assess the validity of the causal relationships.

Results

There was a potential genetic predisposition association identified between CD39+ CD8br AC, CD39+ CD8br % T cell, and the risk of DLBCL (OR=1.51, p<0.001; OR=1.25, p=0.001) (adjusted FDR<0.1). Genetic prediction revealed potential associations between CD25++ CD8br AC, CD28- CD25++ CD8br % T cell, CD39+ CD8br % CD8br, and the risk of FL (OR=1.13, p=0.022; OR=1.28, p=0.042; OR=0.90, p=0.016) (adjusted FDR>0.1). Furthermore, SLE and CD exhibited a genetically predicted potential association with the CD39+ CD8+ Tregs subset. SS and DM were possibly associated with an increase in the quantity of the CD4+ Tregs subset; RA may have reduced the quantity of the CD39+ CD8+ Tregs subset, although no causal relationship was identified. Sensitivity analyses supported the robustness of our findings.

Conclusions

There existed a genetically predicted potential association between the CD39+ CD8+ Tregs subset and the risk of DLBCL, while SLE and CD were genetically predicted to be potentially associated with the CD39+ CD8+ Tregs subset. The CD39+ CD8+ Tregs subset potentially aided in the clinical diagnosis and treatment of SLE or CD complicated by DLBCL.

CD8+ NKs as a potential biomarker of complete response and survival with lenalidomide plus R-GDP in the R2-GDP-GOTEL trial in recurrent/refractory diffuse large B cell lymphoma

Background

Diffuse large B cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma worldwide. DLBCL is an aggressive disease that can be cured with upfront standard chemoimmunotherapy schedules. However, in approximately 35-40% of the patients DLBCL relapses, and therefore, especially in this setting, the search for new prognostic and predictive biomarkers is an urgent need. Natural killer (NK) are effector cells characterized by playing an important role in antitumor immunity due to their cytotoxic capacity and a subset of circulating NK that express CD8 have a higher cytotoxic function. In this substudy of the R2-GDP-GOTEL trial, we have evaluated blood CD8+ NK cells as a predictor of treatment response and survival in relapsed/refractory (R/R) DLBCL patients.

Methods

78 patients received the R2-GDP schedule in the phase II trial. Blood samples were analyzed by flow cytometry. Statistical analyses were carried out in order to identify the prognostic potential of CD8+ NKs at baseline in R/R DLBCL patients.

Results

Our results showed that the number of circulating CD8+ NKs in R/R DLBCL patients were lower than in healthy donors, and it did not change during and after treatment. Nevertheless, the level of blood CD8+ NKs at baseline was associated with complete responses in patients with R/R DLBCL. In addition, we also demonstrated that CD8+ NKs levels have potential prognostic value in terms of overall survival in R/R DLBCL patients.

Conclusion

CD8+ NKs represent a new biomarker with prediction and prognosis potential to be considered in the clinical management of patients with R/R DLBCL.

Clinical trial registration

https://www.clinicaltrialsregister.eu/ctr-search/search?query=2014-001620-29 EudraCT, ID:2014-001620-29.

Cancer Nano-Immunotherapy: The Novel and Promising Weapon to Fight Cancer

Cancer is a complex disease that, despite advances in treatment and the greater understanding of the tumor biology until today, continues to be a prevalent and lethal disease. Chemotherapy, radiotherapy, and surgery are the conventional treatments, which have increased the survival for cancer patients. However, the complexity of this disease together with the persistent problems due to tumor progression and recurrence, drug resistance, or side effects of therapy make it necessary to explore new strategies that address the challenges to obtain a positive response. One important point is that tumor cells can interact with the microenvironment, promoting proliferation, dissemination, and immune evasion. Therefore, immunotherapy has emerged as a novel therapy based on the modulation of the immune system for combating cancer, as reflected in the promising results both in preclinical studies and clinical trials obtained. In order to enhance the immune response, the combination of immunotherapy with nanoparticles has been conducted, improving the access of immune cells to the tumor, antigen presentation, as well as the induction of persistent immune responses. Therefore, nanomedicine holds an enormous potential to enhance the efficacy of cancer immunotherapy. Here, we review the most recent advances in specific molecular and cellular immunotherapy and in nano-immunotherapy against cancer in the light of the latest published preclinical studies and clinical trials.

Location, location, location: mapping the lymphoma tumor microenvironment using spatial transcriptomics

Lymphomas are a heterogenous group of lymphoid neoplasms with a wide variety of clinical presentations. Response to treatment and prognosis differs both between and within lymphoma subtypes. Improved molecular and genetic profiling has increased our understanding of the factors which drive these clinical dynamics. Immune and non-immune cells within the lymphoma tumor microenvironment (TME) can both play a key role in antitumor immune responses and conversely also support lymphoma growth and survival. A deeper understanding of the lymphoma TME would identify key lymphoma and immune cell interactions which could be disrupted for therapeutic benefit. Single cell RNA sequencing studies have provided a more comprehensive description of the TME, however these studies are limited in that they lack spatial context. Spatial transcriptomics provides a comprehensive analysis of gene expression within tissue and is an attractive technique in lymphoma to both disentangle the complex interactions between lymphoma and TME cells and improve understanding of how lymphoma cells evade the host immune response. This article summarizes current spatial transcriptomic technologies and their use in lymphoma research to date. The resulting data has already enriched our knowledge of the mechanisms and clinical impact of an immunosuppressive TME in lymphoma and the accrual of further studies will provide a fundamental step in the march towards personalized medicine.

Survey of genomic and physiological characteristics for survival in lymphoma: The NCI genomic data portal

Lymphoma represents a myriad collection of neoplasms that impact lymphocytes. This cancer often involves disrupted cytokine, immune surveillance, and gene regulatory signaling, sometimes with expression of Epstein Barr Virus (EBV). We explored mutation patterns for People experiencing Lymphoma (PeL) in the National Cancer Institute (NCI) Genomic Data Commons (GDC), which contains detailed, deidentified genomic data on 86,046 people who have/had cancer with 2,730,388 distinctive mutations in 21,773 genes. The database included information on 536 (PeL), with the primary focal sample being the n = 30 who had complete mutational genomic data. We used correlations, independent samples t-tests, and linear regression to compare PeL demographics and vital status on mutation numbers, BMI, and mutation deleterious score across functional categories of 23 genes. PeL demonstrated varied patterns of mutated genes, consistent with most other cancer types. The primary PeL gene mutations clustered around five functional protein groups: transcriptional regulatory proteins, TNF/NFKB and cell signaling regulators, cytokine signaling proteins, cell cycle regulators, and immunoglobulins. Diagnosis Age, Birth Year, and BMI negatively (P < 0.05) correlated with Days to Death, and cell cycle mutations negatively correlated (P = 0.004) with survival days (R² = 0.389). There were commonalities in some PeL for mutations across other cancer types based upon large sequence length, but also for 6 small cell lung cancer genes. Immunoglobulin mutations were prevalent but not for all cases. Research indicates a need for greater personalized genomics and multi-level systems analysis to evaluate facilitators and barriers for lymphoma survival.

The prognostic value of tumor-associated macrophages detected by immunostaining in diffuse large B cell lymphoma: A meta-analysis

Background

The prognostic implication of tumor-associated macrophages (TAMs) in the microenvironment of diffuse large B cell lymphoma (DLBCL) remains controversial.

Methods

A systematic and comprehensive search of relevant studies was performed in PubMed, Embase and Web of Science databases. The quality of the included studies was estimated using Newcastle-Ottawa Scale (NOS).

Results

Twenty-three studies containing a total of 2992 DLBCL patients were involved in this study. They were all high-quality studies scoring ≥ 6 points. High density of M2 TAMs in tumor microenvironment significantly associated with both advanced disease stage (OR= 1.937, 95% CI: 1.256-2.988, P = 0.003) and unfavorable overall survival (OS) (HR = 1.750, 95% CI: 1.188-2.579, P = 0.005) but not associated with poor progression free survival (PFS) (HR = 1.672, 95% CI: 0.864-3.237, P = 0.127) and international prognostic index (IPI) (OR= 1.705, 95% CI: 0.843-3.449, P = 0.138) in DLBCL patients. No significant correlation was observed between the density of CD68+ TAMs and disease stage (OR= 1.433, 95% CI: 0.656-3.130, P = 0.366), IPI (OR= 1.391, 95% CI: 0.573-3.379, P = 0.466), OS (HR=0.929, 95% CI: 0.607-1.422, P = 0.734) or PFS (HR= 0.756, 95% CI: 0.415-1.379, P = 0.362) in DLBCL patients.

Conclusion

This meta-analysis demonstrated that high density of M2 TAMs in the tumor microenvironment was a robust predictor of adverse outcome for DLBCL patients.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO, identifier CRD42022343045.

Management of Aggressive Non-Hodgkin Lymphomas in the Pediatric, Adolescent, and Young Adult Population: An Adult vs. Pediatric Perspective

Non-Hodgkin lymphoma (NHL) is a broad entity which comprises a number of different types of lymphomatous malignancies. In the pediatric and adolescent population, the type and prognosis of NHL varies by age and gender. In comparison to adults, pediatric and adolescent patients generally have better outcomes following treatment for primary NHL. However, relapsed/refractory (R/R) disease is associated with poorer outcomes in many types of NHL such as diffuse large B cell lymphoma and Burkitt lymphoma. Newer therapies have been approved in the use of primary NHL in the pediatric and adolescent population such as Rituximab and other therapies such as chimeric antigen receptor T-cell (CAR T-cell) therapy are under investigation for the treatment of R/R NHL. In this review, we feature the characteristics, diagnosis, and treatments of the most common NHLs in the pediatric and adolescent population and also highlight the differences that exist between pediatric and adult disease. We then detail the areas of treatment advances such as immunotherapy with CAR T-cells, brentuximab vedotin, and blinatumomab as well as cell cycle inhibitors and describe areas where further research is needed. The aim of this review is to juxtapose established research regarding pediatric and adolescent NHL with recent advancements as well as highlight treatment gaps where more investigation is needed.