Brief report Recurrent involvement of the REL and BCL11A loci in classical Hodgkin lymphoma

Comparative genomic hybridization studies have shown gains in chromosome region 2p as the most common imbalance in classi-cal Hodgkin lymphoma (cHL). The minimal region of gain contained 2 candidate onco-genes, REL and BCL11A. This study exam-ined the involvement of REL and BCL11A loci in 44 primary cases of cHL by combined immunophenotyping and interphase cytoge-netics (FICTION). A median 2p13 copy num-ber above the tetraploid range was detected in 24 (55%) cases. Adjustment for centro-mere 2 copy number indicated gains of 2p13 in 11 of 31 cHLs (35%) with 8 (26%) high-level amplifications. One cHL displayed se-lective amplification of the REL locus not affecting BCL11A; another case studied by FICTION and a cHL with cytogenetic 2p change investigated by fluorescence in situ hybridization showed signal patterns sug-gesting breakpoints in the region spanned by the REL probe. These data indicate that REL rather than BCL11A may be the target of the 2p13 alterations in cHL. (Blood. 2002