Project description:Plasmablastic lymphoma is a high grade B cell lymphoma with plasmablastic morphology and a terminally differentiated B cell immunophenotype, usually arising in the setting of immunodeficiency and often demonstrating Epstein Barr Virus positivity. The molecular and genetic mechanisms underlying the pathogenesis of PBL are largely unknown. To better understand its pathogenesis, herein we have analyzed global gene expression of PBL and compared that to gene expression profiles of diffuse large B cell lymphoma. While overlaps in transcriptomes between these malignancies were identified, we have shown that the gene expression profile of plasmablastic lymphoma is distinct, demonstrating striking downregulation of B cell receptor signaling genes, BCL6, BCL11A SPI-B, targets of NFKB1, and upregulation of mitochondrial genes, PRMT5, MYC and MYC targets and IL21, implicating these alterations in the pathogenesis of this lymphoma. In addition we show the usefulness of SWAP-70 immunohistochemistry in the differentiation of immunoblastic diffuse large B cell lymphoma and plasmablastic lymphoma. Our findings provide justification for considering plasmablastic lymphoma as a specific lymphoma entity and provide insight into the unique transcriptional aberrations occurring in this high-grade lymphoma. Expression profiles of 15 plasmablastic lymphomas and 10 diffuse large B-cell lymphomas were obtained using Afymmetrix U133A2 microarrays.
Project description:Follicular lymphoma (FL) is one of the most common types of indolent B-cell lymphoma in Western countries. FL commonly transforms to more aggressive diffuse large B-cell lymphoma (DLBCL) at reported frequencies between 15 - 60%. We have used microarray comparative genomic hybridisation (aCGH) at 1 Mb resolution to study copy number changes in paired tumor samples (primary FL and a subsequent tDLBCL) as well as de novo DLBCL cases to outline genetic mechanisms of transformation from follicular lymphoma to diffuse large B-cell lymphoma.
Project description:Plasmablastic lymphoma is an aggressive B-cell lymphoma with an immunoblastic/large cell morphology anda plasmacytic differentiation. The differential diagnosis with Burkitt lymphoma, plasma cell myeloma and some variants of diffuse large B-cell lymphoma may be challenging due to the overlapping morphological, genetic and immunophenotypic features. Furthermore, the profile of chromosomal alterations is not well known.
