Project description:The pathogenesis of nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) and its relationship to other lymphomas are largely unknown. This is partly due to the technical challenge of analyzing its rare neoplastic L&H cells, which are dispersed in an abundant non-neoplastic cellular microenvironment. We performed a genome-wide expression study of microdissected lymphocytic and histiocytic (L&H) lymphoma cells in comparison to normal and other malignant B cells, which indicates a relationship of L&H cells to and/or origin from germinal center B cells at transition to memory B cells. L&H cells show a surprisingly high similarity to the tumor cells of T cell-rich B cell lymphoma and classical Hodgkin lymphoma, a partial loss of their B cell phenotype and deregulation of many apoptosis-regulators and putative oncogenes. Importantly, L&H cells are characterized by constitutive NF-κB activity and aberrant ERK signaling. Thus, these findings shed new light on the nature of L&H cells, revealed several novel pathogenetic mechanisms in NLPHL, and may help in differential diagnosis and lead to novel therapeutic strategies. Experiment Overall Design: Analysis of differential gene expression in primary human lymphoma cells of nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) in comparison with primary lymphoma cells of classical Hodgkin lymphoma cells and other B-non-Hodgkin lymphoma (B-NHL) samples and subsets of non-neoplastic B lymphocytes isolated from blood or tonsils. 67 gene expression profiles were analysed.
Project description:T-cell/histiocyte rich B cell lymphoma (THRBL) and nodular lymphocyte predominant Hodgkin's lymphoma (NLPHL) share some morphological characteristics, including a prominent stromal reaction, but display a markedly different prognosis. To investigate the difference between the stromal reactions of these lymphomas at the molecular level, we performed microarray expression profiling on a series of THRBL and NLPHL cases. Keywords: lymphoma, NLPHL, THRBL, stromal reaction
Project description:T-cell/histiocyte rich B cell lymphoma (THRBL) and nodular lymphocyte predominant Hodgkin's lymphoma (NLPHL) share some morphological characteristics, including a prominent stromal reaction, but display a markedly different prognosis. To investigate the difference between the stromal reactions of these lymphomas at the molecular level, we performed microarray expression profiling on a series of THRBL and NLPHL cases. Experiment Overall Design: Microarray expression profiling was performed for 10 NLPHL and 10 THRBL cases. A pool of 5 reactive lymph nodes was included as a reference sample.
Project description:The pathogenesis of nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) and its relationship to other lymphomas are largely unknown. This is partly due to the technical challenge of analyzing its rare neoplastic L&H cells, which are dispersed in an abundant non-neoplastic cellular microenvironment. We performed a genome-wide expression study of microdissected lymphocytic and histiocytic (L&H) lymphoma cells in comparison to normal and other malignant B cells, which indicates a relationship of L&H cells to and/or origin from germinal center B cells at transition to memory B cells. L&H cells show a surprisingly high similarity to the tumor cells of T cell-rich B cell lymphoma and classical Hodgkin lymphoma, a partial loss of their B cell phenotype and deregulation of many apoptosis-regulators and putative oncogenes. Importantly, L&H cells are characterized by constitutive NF-κB activity and aberrant ERK signaling. Thus, these findings shed new light on the nature of L&H cells, revealed several novel pathogenetic mechanisms in NLPHL, and may help in differential diagnosis and lead to novel therapeutic strategies.
Project description:We recently identified a family with lymphoma predisposition where a heterozygous truncating germline mutation in TET2 segregated with nodular lymphocyte predominant Hodgkin lymphoma. In a clinical trial of one year, we investigated the effects of oral 1 g/day vitamin C supplementation on DNA methylation by analyzing genome-wide DNA methylation and gene expression patterns from the family members.
Project description:Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) is an indolent lymphoma, but can transform into diffuse large B cell lymphoma (DLBCL), showing a more aggressive clinical behavior. Little is known about these cases on the molecular level. Therefore, the aim of the present study was to characterize DLBCL transformed from NLPHL (LP-DLBCL) by gene expression profiling (GEP). GEP revealed an inflammatory signature pinpointing to a specific host response. In a coculture model resembling this host response, DEV tumor cells showed an impaired growth behavior. Mechanisms involved in the reduced tumor cell proliferation included a downregulation of MYC and its target genes. Lack of MYC expression was also confirmed in 12/16 LP-DLBCL by immunohistochemistry. Furthermore, CD274/PD-L1 was upregulated in tumor cells after coculture with T cells or monocytes and its expression was validated in 12/19 cases of LP-DLBCL. Thereby, our data provide new insights into the pathogenesis of LP-DLBCL and a concrete explanation of the relatively low tumor cell content. Moreover, our results suggest that treatment of these patients with checkpoint inhibitors may enhance an already ongoing host response in these patients.