Joos S, Otano-Joos MI, Ziegler S, Brüderlein S, du Manoir S, Bentz M, Möller P, and Lichter P. Primary mediastinal (thymic) B-cell lymphoma is characterized by gains of chromosomal material including 9p and amplification of the REL gene. Blood 87: 1571-1578

Deutsches Krebsforschungszentrum, Abt. Organisation komplexer Genome, Heidelberg, Germany.
Blood (Impact Factor: 10.45). 03/1996; 87(4):1571-8.
Source: PubMed


Primary mediastinal (thymic) B-cell lymphoma is a high-grade non-Hodgkin's lymphoma with unique features. By using comparative genomic hybridization and interphase cytogenetics, 26 tumors were analyzed to identify genomic imbalances. Gains of chromosomal material were much more frequent than losses (110 v 10) and involved chromosomes 9p, 12q, and Xq (31% to 50%). Interestingly, gain of Xq coincided with gain of 9p. Distinct high-level amplifications were found in four subregions. In 2 cases, amplifications of proto-oncogene REL were shown by filter hybridization, indicating a possible pathogenic role of this gene. The characteristic pattern of chromosomal imbalances distinct from other B-cell lymphomas suggests a specific pathway of genetic changes associated with this lymphoma.

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    • "Nuclear localisation of REL, one of the NFκB complex proteins, is related to the activation of the NFκB pathway. Genomic gains and amplifications of the REL protooncogene locus on the short arm of chromosome 2p are present in over half of the PMBCL cases and associated with the nuclear position of REL [25, 26]. JAK-STAT is another major pathway responsible for the regulation of cell proliferation. "
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    • "Recent studies have highlighted many genetic similarities as well. Both entities show gains at 2p15 (REL locus) and 9p24 (JAK2 locus) and breaks at CIITA (38% of PMBCL and 15% of cHL) [18–20]. The presence of CIITA rearrangement significantly correlates with shorter disease-specific survival for patients with PMBCL [20]. "
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    • "In addition, PMBL and HL share oncogenic mechanisms, including activation of the NF-kB pathway (Lam et al., 2005; Rosenwald et al., 2003; Savage et al., 2003). A recurrent genomic copy number gain in these lymphomas involves a region on chromosome band 9p24, which occurs in 35%–45% of PMBL cases (Joos et al., 1996; Lenz et al., 2008; Meier et al., 2009; Rosenwald et al., 2003) and 33% of HL cases (Joos et al., 2000, 2003). One gene in this interval is JAK2, which encodes a tyrosine kinase that mediates signaling downstream of several cytokine receptors (Bentz et al., 2001; Joos et al., 2003, 2000; Meier et al., 2009; Rosenwald et al., 2003). "
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