Validation and characterization of TBL1XR1/TP63 fusion in peripheral T-cell lymphomas. (A) Junction plot of mate-pair data showing inv(3)(q26q28) involving TBL1XR1 and TP63. Arrows indicate breakpoints. (B) Schematic diagram of inv(3)(q26q28) with resultant gene fusions. P indicates promoter region. (C) RT-PCR for fusion transcripts 1 and 2 in cases with (TCL29) and without (TCL32 and FE-PD) inv(3)(q26q28). (D) Partial results of Sanger sequencing (nucleotides in red) of TBL1XR1/TP63 (fusion transcript 2) in TCL29, with TP63 breakpoint (arrow) showing loss of transactivation (TA) domain and retention of DNA-binding domain (DBD), similar to TP63 isoforms encoding dominant-negative ΔNp63. (E) QPCR in 16 PTCL tissue samples shows higher expression of p63 in cases with inv(3)(q26q28) (n = 3) than in cases without this rearrangement (n = 13); TBL1XR1 is expressed more uniformly. (F) Western blot of protein from PTCL tissue samples without (TCL3) and with (TCL5) TBL1XR1/ΔNp63; the fusion protein runs at ∼ 100 kDa.