Project description:Anaplastic large cell lymphoma (ALCL) is an aggressive, CD30+ T-cell lymphoma of children and adults. ALK fusion transcripts or mutations in the JAK-STAT pathway are observed in most ALCL tumors, but the mechanisms underlying tumorigenesis are not fully understood. Here we show that dysregulated STAT3, together with a core transcriptional regulatory circuit consisting of BATF3–IRF4–IKZF1, co-occupies gene enhancers to establish an oncogenic transcription program and maintain the malignant state of ALCL. Critical downstream targets of this network in ALCL cells include the proto-oncogene MYC, which requires active STAT3 to facilitate high levels of MYC transcription. The activity of this auto-regulatory transcription loop is reinforced by MYC binding to the enhancer regions associated with STAT3 and each of the core regulatory transcription factors. These findings provide new insights for understanding how dysregulated signaling pathways hijack cell-type-specific transcriptional machinery to drive tumorigenesis and create therapeutic vulnerabilities in genetically defined tumors.
Project description:Anaplastic large cell lymphoma (ALCL) is an aggressive, CD30+ T-cell lymphoma of children and adults. ALK fusion transcripts or mutations in the JAK-STAT pathway are observed in most ALCL tumors, but the mechanisms underlying tumorigenesis are not fully understood. Here we show that dysregulated STAT3, together with a core transcriptional regulatory circuit consisting of BATF3–IRF4–IKZF1, co-occupies gene enhancers to establish an oncogenic transcription program and maintain the malignant state of ALCL. Critical downstream targets of this network in ALCL cells include the proto-oncogene MYC, which requires active STAT3 to facilitate high levels of MYC transcription. The activity of this auto-regulatory transcription loop is reinforced by MYC binding to the enhancer regions associated with STAT3 and each of the core regulatory transcription factors. These findings provide new insights for understanding how dysregulated signaling pathways hijack cell-type-specific transcriptional machinery to drive tumorigenesis and create therapeutic vulnerabilities in genetically defined tumors.
Project description:Anaplastic large cell lymphoma (ALCL) is an aggressive, CD30+ T-cell lymphoma of children and adults. ALK fusion transcripts or mutations in the JAK-STAT pathway are observed in most ALCL tumors, but the mechanisms underlying tumorigenesis are not fully understood. Here we show that dysregulated STAT3, together with a core transcriptional regulatory circuit consisting of BATF3–IRF4–IKZF1, co-occupies gene enhancers to establish an oncogenic transcription program and maintain the malignant state of ALCL. Critical downstream targets of this network in ALCL cells include the proto-oncogene MYC, which requires active STAT3 to facilitate high levels of MYC transcription. The activity of this auto-regulatory transcription loop is reinforced by MYC binding to the enhancer regions associated with STAT3 and each of the core regulatory transcription factors. These findings provide new insights for understanding how dysregulated signaling pathways hijack cell-type-specific transcriptional machinery to drive tumorigenesis and create therapeutic vulnerabilities in genetically defined tumors.
Project description:Ophelia syndrome is characterized by the coincidence of severe neuropsychiatric symptoms, classical Hodgkin lymphoma, and the presence of antibodies to the metabotropic glutamate 5 receptor (mGluR5). Little is known about the pathogenetic link between these symptoms and the role anti-mGluR5-antibodies play. We investigated lymphoma tissue from patients with Ophelia syndrome and with isolated classical Hodgkin lymphoma by quantitative immunocytochemistry for mGluR5-expression. Further, we studied the L-1236, L-428, L-540, SUP-HD1, KM-H2, and HDLM-2 classical Hodgkin lymphoma cell lines by FACS and Western blot for mGluR5-expression, and by transcriptome analysis. mGluR5 surface expression differed significantly in terms of receptor density, distribution pattern, and percentage of positive cells. Highest levels were found in the L-1236 line. RNA-sequencing revealed more than 800 genes that were higher expressed in L-1236 in comparison to classical Hodgkin lymphoma-controls. High mGluR5-expression was associated with upregulation of PI3K/AKT and MAPK pathways and of downstream targets (e.g. EGR1) known to be involved in classical Hodgkin lymphoma progression. Finally, mGluR5 expression was increased in the classical Hodgkin lymphoma-tissue of our Ophelia syndrome patient in contrast to five classical Hodgkin lymphoma-patients without autoimmune encephalitis. Given the association of encephalitis and classical Hodgkin’s lymphoma in Ophelia syndrome, it is possible that mGluR5-expression on classical Hodgkin lymphoma cells not only drives tumor progression, but may also trigger anti-mGluR5 encephalitis already before classical Hodgkin lymphoma-manifestation.
Project description:Here we investigated the effects of JAK/STAT pharmacological inhibition on cHL cell models using ruxolitinib, a JAK 1/2 inhibitor. We use five classical Hodgkin lymphoma cell lines: L428, L1236, L540, KMH2, L591
Project description:Global proteomics profiling of anaplastic large cell lymphoma cell lines DEL, SU-DHL-1 (ALK+), Mac-1, Mac-2A (ALK-) as well as Hodgkin lymphoma cell lines L-428, L-540, L-1236 and HDLM-2.
Project description:Analysis of differential gene expression in human non-Hodgkin`s lymphoma cell lines and a primary leukaemic tumor sample of large cell anaplastic type in comparison with Hodgkin`s lymphoma cell lines and other non-Hodgkin`s lymphoma samples and non-neoplastic lymphocytes Keywords: cell type comparison
Project description:The aim was to dissect molecular changes in histone and non-histone protein acetylation dynamics following the genetic or pharmacological inhibition of HDAC activity in a model of Anaplastic Large Cell Lymphoma (ALCL), a T cell non-Hodgkin lymphoma, predominantly found in children and adolescents.
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. The present study complements the GSE12453 and GSE14879 records by adding the following 10 samples: 5 primary tumor samples and 5 cell line samples. The 5 primary tumor samples represent 1000-2000 neoplastic cells microdissected from frozen biopsies of 5 cases of primary mediastinal B-cell lymphoma (PMBL). The 5 cell line samples represent 500-1000 living neoplastic cells isolated by fluorescence-activated cell sorting from growing cultures of the classical Hodgkin lymphoma (cHL) cell lines L1236, L428, KMH2 and HDLM2 and the lymphocyte-predominant Hodgkin lymphoma (lpHL) cell line DEV.
Project description:Analysis of differential gene expression in human non-Hodgkin`s lymphoma cell lines and a primary leukaemic tumor sample of large cell anaplastic type in comparison with Hodgkin`s lymphoma cell lines and other non-Hodgkin`s lymphoma samples and non-neoplastic lymphocytes Experiment Overall Design: Samples were analyzed to be compared to publically available data sets