Molecular Characterization of Immunoglobulin Gene Rearrangements in Diffuse Large B-Cell Lymphoma

Autor: Emilia Pardal, Rocío Corral, Santiago Montes-Moreno, Miguel Alcoceba, Alejandro Martín, Ramón García-Sanz, Marcos González, Luis Marín, Noemi Puig, Ana Balanzategui, M. Eugenia Sarasquete, M. Dolores Caballero, Jesús F. San Miguel, Eva González-Barca, M. Carmen Chillón, Teresa Guzmán Flores, Elena Sebastián, David Gonzalez
Rok vydání: 2012
Předmět:
Zdroj: The American Journal of Pathology. 181:1879-1888
ISSN: 0002-9440
DOI: 10.1016/j.ajpath.2012.07.028
Popis: The pathogenesis of diffuse large B-cell lymphoma (DLBCL) remains partially unknown. The analysis of the B-cell receptor of the malignant cells could contribute to a better understanding of the DLBCL biology. We studied the molecular features of the immunoglobulin heavy chain (IGH) rearrangements in 165 patients diagnosed with DLBCL not otherwise specified. Clonal IGH rearrangements were amplified according to the BIOMED-2 protocol and PCR products were sequenced directly. We also analyzed the criteria for stereotyped patterns in all complete IGHV-IGHD-IGHJ (V-D-J) sequences. Complete V-D-J rearrangements were identified in 130 of 165 patients. Most cases (89%) were highly mutated, but 12 sequences were truly unmutated or minimally mutated. Three genes, IGHV4-34 , IGHV3-23 , and IGHV4-39 , accounted for one third of the whole cohort, including an overrepresentation of IGHV4-34 (15.5% overall). Interestingly, all IGHV4-34 rearrangements and all unmutated sequences belonged to the nongerminal center B-cell–like (non-GCB) subtype. Overall, we found three cases following the current criteria for stereotyped heavy chain VH CDR3 sequences, two of them belonging to subsets previously described in CLL. IGHV gene repertoire is remarkably biased, implying an antigen-driven origin in DLBCL. The particular features in the sequence of the immunoglobulins suggest the existence of particular subgroups within the non-GCB subtype.
Databáze: OpenAIRE