Project description:Classic Hodgkin lymphoma (CHL) harbors a small number of Hodgkin-Reed-Sternberg (HRS) cells scattering among numerous lymphocytes. HRS cells are surrounded by distinct CD4+ T cells in a rosette-like manner. These CD4+ T cell rosettes play an important role in tumor microenvironment (TME) of CHL. To elucidate the interaction between HRS cells and CD4+ T cell rosettes, we performed digital spatial profiling (DSP) and compared gene expression profile between CD4+ T cell rosettes and other CD4+ cells separated from HRS cells. programed cell death-1 (PD-1) and tumor necrosis factor receptor superfamily member (TNFRSF) 4 were significantly highly expressed in CD4+ T cell rosettes than others. Immunohistochemistry confirmed PD-1 and TNFRSF4-expressing CD4+ T cell rosettes. This study introduced the new pathological approach to TME and provided deeper insight to CD4+ T cells in CHL.
Project description:Classic Hodgkin lymphoma (CHL) harbors a small number of Hodgkin-Reed-Sternberg (HRS) cells scattered among numerous lymphocytes. HRS cells are surrounded by distinct CD4+ T cells in a rosette-like manner. These CD4+ T cell rosettes play an important role in the tumor microenvironment (TME) of CHL. To elucidate the interaction between HRS cells and CD4+ T cell rosettes, we completed digital spatial profiling to compare the gene expression profiles of CD4+ T cell rosettes and other CD4+ T cells separated from the HRS cells. Tumor necrosis factor receptor superfamily member (TNFRSF) 4 or OX40 showed significantly higher expression in CD4+ T cell rosettes when compared with other CD4+ T cells. Programed cell death-1 (PD-1) and cytotoxic T lymphocyte associated protein 4 (CTLA-4) tended to be highly expressed in CD4+ T cell rosettes compared to other CD4+ T cells. Immunohistochemistry revealed variable expression of these immune checkpoint molecules in the CD4+ T cell rosettes. This study introduced a new pathological approach to the TME and provided deeper insight into CD4+ T cells in CHL.
Project description:Epstein–Barr virus-positive (EBV+) diffuse large B-cell lymphoma (DLBCL) and EBV+ classic Hodgkin lymphoma (CHL) are major B-cell lymphomas with EBV infection in elderly patients. Although they are regarded as distinct clinicopathologic entities, distinguishing EBV+ CHL from EBV+ DLBCL is often challenging because of their overlapping histological and immunophenotypic features. We characterized the spectrum of EBV+ large B-cell lymphoma in 57 patients aged ≥50 years, including 35 EBV+ DLBCL (12 polymorphic DLBCL [pDLBCL] and 23 monomorphic DLBCL [mDLBCL]) and 22 EBV+ CHL. Gene expression profiling revealed interferon-γ (IFNγ)-enrichment with overexpression of indoleamine 2,3-dioxygenase 1 (IDO1), an immunosuppressive enzyme, in more than half of pDLBCL (5/8), but less in mDLBCL (3/19) and CHL (1/19). Fluorescence in situ hybridization showed a higher frequency of 9p24.1-altered cells in CHL (54%; interquartile range [IQR], 42%–89%), but lower in pDLBCL (18%; IQR, 12%–23%) and mDLBCL (5%; IQR, 0%–30%). Notably, immunohistochemical expression of PDL1 was higher in pDLBCL than in mDLBCL, suggesting IFNγ-mediated upregulation. DLBCL with EBV latency type III (n = 13) exhibited lower tumor PDL1 expression and reduced IDO1-enriched microenvironment. Multivariate analysis of the total cohort revealed that both EBV latency type III and Eastern Cooperative Oncology Group performance status ≥2 were independently associated with shorter overall survival. EBV+ large B-cell lymphoma spectrum was reclassified into four molecular groups: (1) EBV latency type III suggestive of immune senescence (n = 10, 22%), (2) high proportion of 9p24.1-alteration (n = 9, 20%); (3) high IFNγ signature score (n = 9, 20%), and (4) low IFNγ signature score (n = 18, 39%). Moreover, these groups were identified using surrogate immunohistochemical markers: EBNA2, PDL1, and IDO1. In conclusion, the molecular studies assessing tumor–host interaction enhances understanding of the EBV+ large B-cell lymphoma spectrum and benefits pathological diagnosis and clinical management.
Project description:Circulating tumor DNA (ctDNA) as a biomarker of disease activity in classic Hodgkin lymphoma (cHL) patients are still not well-defined. By profiling primary tumors and ctDNA, we identified common variants between primary tumors and longitudinal plasma samples in most of the cases, confirming high PBatial and temporal heterogeneity. Though ctDNA analyses mirrored HRS cell genetics overall, the prevalence of variants shows that none of them can be used as a single biomarker. Conversely, the estimation of hGE/mL, based in total ctDNA quantification, reflects disease activity and is almost perfectly correlated with standard parameters such as PET/CT that are associated with refractoriness.
Project description:The cellular microenvironment in classical Hodgkin lymphoma (cHL) is dominated by a mixed infiltrate of inflammatory cells with typically only about 1% Hodgkin and Reed/Sternberg (HRS) tumor cells. T cells are usually the largest population of cells in the cHL microenvironment, encompassing T helper (Th) cells, regulatory T (Treg) cells and cytotoxic T cells. Th and Treg cells presumably provide essential survival signals for HRS cells. Treg cells are also involved in rescuing HRS cells from anti-tumor immune responses. An understanding of the immune evasion strategies of HRS cells is not only highly relevant for a characterization of the pathophysiology of cHL, but also clinically, given the current treatment approaches targeting checkpoint inhibitors. Here, we characterized the cHL-specific CD4+ T cell infiltrate regarding its role in immune evasion. Global gene expression analysis of CD4+ Th and Treg cells isolated from cHL lymph nodes and reactive tonsils revealed that Treg cell signatures were enriched in CD4+ Th cells of cHL. Hence, HRS cells may induce a Treg differentiation in Th cells, which was supported by in vitro studies with Th cells and cHL cell lines. Furthermore, we found indication for immune-suppressive purinergic signaling and a role of the inhibitory receptor-ligand pairs BTLA-HVEM and CD200R-CD200 in promoting immune evasion. Taken together, this study reveals that the immune evasion strategies in cHL are even more complex and multifaceted than previously recognized.
Project description:To investigate the biological differences between EBV-/HIV-, EBV+/HIV- and EBV+/HIV+ classic Hodgkin lymphoma, we performed RNA sequencing of 19 pre-treatment formalin-fixed paraffin-embedded (FFPE) whole lymph node biopsies of cHL.
Project description:The pathogenesis of classical Hodgkin lymphoma (cHL), the most common lymphoma in the young, is still enigmatic, largely because its Hodgkin and Reed-Sternberg (HRS) tumor cells are rare in the involved lymph node and therefore difficult to analyze. Here, by overcoming this technical challenge and performing for the first time a genome-wide transcriptional analysis of microdissected HRS cells in comparison to other B-cell lymphomas, cHL lines and normal B-cell subsets, we show that they differ extensively from the usually studied cHL cell lines, that the lost B-cell identity of cHLs is not linked to the acquisition of a plasma cell-like gene expression program, and that Epstein-Barr virus infection of HRS cells has a minor transcriptional influence on the established cHL clone. Moreover, although cHL appears a distinct lymphoma entity overall, HRS cells of its histological subtypes diverged in their similarity to other related lymphomas. Unexpectedly, we identified two molecular subgroups of cHL associated to differential strengths of the transcription factor activity of the NOTCH1, MYC and IRF4 proto-oncogenes. Finally, HRS cells display deregulated expression of several genes potentially highly relevant to lymphoma pathogenesis, including silencing of the apoptosis-inducer BIK and of INPP5D, an inhibitor of the PI3K-driven oncogenic pathway.