0000000000115777

AUTHOR

German Ott

EZH2 mutations are frequent and represent an early event in follicular lymphoma

Gain of function mutations in the H3K27 methyltransferase EZH2 represent a promising therapeutic target in germinal center lymphomas. In this study, we assessed the frequency and distribution of EZH2 mutations in a large cohort of patients with follicular lymphoma (FL) (n = 366) and performed a longitudinal analysis of mutation during the disease progression from FL to transformed FL (tFL) (n = 33). Mutations were detected at 3 recurrent mutation hot spots (Y646, A682, and A692) in 27% of FL cases with variant allele frequencies (VAF) ranging from 2% to 61%. By comparing VAF of EZH2 with other mutation targets (CREBBP, MLL2, TNFRSF14, and MEF2B), we were able to distinguish patients harbori…

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A Tuft Cell-Like Signature Is Highly Prevalent in Thymic Squamous Cell Carcinoma and Delineates New Molecular Subsets Among the Major Lung Cancer Histotypes.

Abstract Introduction In-depth genomic characterization of thymic epithelial tumors (TETs), comprising thymomas and thymic carcinomas (TCs), failed to identify targetable mutations and suggested unique biology of TETs, including KIT expression in most TCs. Recently, tuft cell–like medullary thymic epithelial cells were identified in the murine thymus, and our reanalysis of the published gene expression data revealed that these cells express KIT. In addition, recently, a minor subset of SCLCs with tuft cell–like features was described. Methods We interrogated mRNA expression data from our tumor cohorts (N = 60) and publicly available, independent data sets from TETs and NSCLC (N = 1199) for …

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GTF2I Mutation in Thymomas: Independence From Racial-Ethnic Backgrounds. An Indian/German Comparative Study

Thymomas are the most frequent adult mediastinal cancers. Their etiology is unknown and their pathogenesis poorly understood. Racial, ethnic and environmental factors influence tumorigenesis in many cancers, but their role in thymomas remains unclear to date. In this study that included pretreatment thymoma cases from India and Germany (n = 37 and n = 77, respectively) we compared i) the prevalence of the thymoma-specific chromosome 7 c.74146970T > A mutation of the GTF2I gene in type A and AB thymomas; ii) epidemiological features; and iii) the frequency of myasthenia gravis (MG). Due to a known predominance of GTF2I mutation in A and AB histotypes, we included only a marginal numbe…

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cFLIPoverexpression in T cells in thymoma‐associated myasthenia gravis

OBJECTIVE: The capacity of thymomas to generate mature CD4+ effector T cells from immature precursors inside the tumor and export them to the blood is associated with thymoma-associated myasthenia gravis (TAMG). Why TAMG(+) thymomas generate and export more mature CD4+ T cells than MG(-) thymomas is unknown. METHODS: Unfixed thymoma tissue, thymocytes derived thereof, peripheral blood mononuclear cells (PBMCs), T-cell subsets and B cells were analysed using qRT-PCR and western blotting. Survival of PBMCs was measured by MTT assay. FAS-mediated apoptosis in PBMCs was quantified by flow cytometry. NF-κB in PBMCs was inhibited by the NF-κB-Inhibitor, EF24 prior to FAS-Ligand (FASLG) treatment …

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Thymic Hyperplasia with Lymphoepithelial Sialadenitis (LESA)-Like Features: Strong Association with Lymphomas and Non-Myasthenic Autoimmune Diseases.

Thymic hyperplasia (TH) with lymphoepithelial sialadenitis (LESA)-like features (LESA-like TH) has been described as a tumor-like, benign proliferation of thymic epithelial cells and lymphoid follicles. We aimed to determine the frequency of lymphoma and autoimmunity in LESA-like TH and performed retrospective analysis of cases with LESA-like TH and/or thymic MALT-lymphoma. Among 36 patients (21 males) with LESA-like TH (age 52 years, 32&ndash

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Clinicogenetic Risk Models in Patients Randomized to Receive Consolidative Autologous Stem-Cell Transplantation after Frontline R-CHOP for Advanced Follicular Lymphoma: An Analysis from the GLSG2000 Trial

Abstract Introduction: Advanced follicular lymphoma (FL) is a clinically and molecularly heterogeneous disease. About 20% of patients have early progression of disease (POD) and short overall survival (OS). We have previously shown that integration of lymphoma-specific gene mutations and clinical factors improves pretreatment risk stratification (Pastore, 2015) and prediction of early POD (i.e., within 24 months, POD24; Jurinovic, 2016). Recently, we have shown that high-dose therapy (HDT) followed by autologous stem-cell transplantation (ASCT) is an effective treatment option for eligible patients with high-risk disease as defined by POD24 (Jurinovic, 2018). Here, we aimed to explore wheth…

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