Gene expression signature of lymphocyte in acute lymphoblastic leukemia patients immediately after total body irradiation.

Molecular mechanisms involved in TBI preconditioning before allogenetic transplantation remain unclear. To elucidate possible signaling pathway in it, gene expression profiles of peripheral lymphocytes were compared between samples 24h after each 4.5 Gy total body irradiation treatment (total 9 Gy) from 4 adult ALL patients. 478 significant expressed genes and three unique patterns were identified. Of these, a dominant progressively repressed expression of genes involved in ubiquitin-dependent process and repressed expression only at 9 Gy of genes involved in allograft rejection and graft-versus-host disease pathways were observed. The results suggest these pathways may play important roles for subsequent transplantation.