Expression of the recombination activating genes (RAG1 and RAG2) is not detectable in Epstein-Barr virus-associated human lymphomas.
The expression of the recombination activating genes (RAG1 and RAG2) is largely restricted to immature lymphoid cells. Previous studies have suggested that Epstein-Barr virus (EBV) infection may lead to a re-induction of RAG expression in mature B lymphocytes. To assess the significance of this mechanism for the pathogenesis of malignant lymphomas, we have examined the expression of RAG genes in 11 cases of EBV-associated endemic Burkitt's lymphoma (BL), 25 cases of Hodgkin's disease (HD, 17 EBV(+), 8 EBV(-)) and 10 cases of follicular non-Hodgkin's lymphoma (NHL). Using in situ hybridization, expression of the RAGs was detected in cortical thymocytes in normal thymus and in the tumor cells of 2 of 3 lymphoblastic NHL. By contrast, there was no detectable RAG expression in the BL, HD and follicular NHL cases. Our results indicate that re-induction of RAG expression does not occur in human lymphomas in vivo. Thus, it is unlikely to play a role in the development of translocations involving immunoglobulin gene loci which are characteristically found in BL and follicular NHL. Moreover, our study shows that in situ hybridization is a suitable method for the analysis of RAG expression in human tissue sections.
Institute for Pathology, Friedrich-Alexander University, Erlangen, Germany.
N
N
Meru
A
A
Jung
R
R
Lisner
G
G
Niedobitek
D002051:Burkitt Lymphoma / Q000235:genetics* / Q000821:virology*; D004268:DNA-Binding Proteins / Q000235:genetics*; D015870:Gene Expression; D016654:Genes, RAG-1 / Q000235:genetics*; D004854:Herpesvirus 4, Human / Q000235:genetics; D006689:Hodgkin Disease / Q000235:genetics*; D006801:Humans; D017403:In Situ Hybridization; D008224:Lymphoma, Follicular / Q000235:genetics; D008228:Lymphoma, Non-Hodgkin / Q000235:genetics*; D009687:Nuclear Proteins; D015138:RNA, Nuclear / Q000032:analysis; D012367:RNA, Viral / Q000032:analysis; D013950:Thymus Gland / Q000378:metabolism; D019895:Transposases / Q000235:genetics
D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; C499311:RAG2 protein, human; D015138:RNA, Nuclear; D012367:RNA, Viral; C064655:V(D)J recombination activating protein 2; D019895:Transposases