Involvement of theREL and BCL11A loci in cHL detected by FISH and FICTION.

(A,B) FICTION analyses using probes for REL (green signals) and CEP2 (red signals) showing multiple copies of REL in cHL11 (A) and a high-level amplification of REL (arrow) in cHL1 (B). The tumor cells of both cases contain 4 copies of CEP2. (C-F) FISH (C,E) and FICTION (D,F) analyses with probes for REL(green signals) and BCL11A (red signals) loci. (C) FISH in case cHL45 with del(2)(p14p23) and add(2)(p?)x2 identified a massive copy gain of both REL and BCL11A loci in HRS nuclei most likely due to 2 chromosomes containing a 2p amplicon. Two colocalized signals for each probe indicate 2 additional intactREL/BCL11A loci. (D) Amplification of the RELlocus (arrows) without coamplification of BCL11A locus in cHL8. (E,F) Signal patterns indicating a translocation breakpoint within the region spanned by the REL probe or, less likely, between the REL and BCL11A loci. (E) FISH in case cHL46 with t(2;22)(p16;q12) and der(9)t(2;9)(p16;p22) revealed 2 colocalized signals for the REL and BCL11A loci and an additional isolated signal for the REL locus (arrow). (F) FICTION in cHL17 showing 2 intact BCL11A/REL fusions and one split of the REL probe, displayed as one isolated green (arrow) and one red/tiny green fusion signal (arrowhead).