Identification of a melanoma antigen, PRAME, as a BCR/ABL-inducible gene

In order to elucidate molecular events in BCR/ABL-induced transformation, w e adopted a polymerase chain reaction (PCR)-based technique of differential display and compared mRNA expression in human factor-dependent cells, TF-1 , with that in factor-independent cells, ID-1, which were established from TF-1 cells by transfection of BCR/ABL, Cloning and sequencing of a gene whi ch was upregulated in ID-1 cells revealed that the gene was identical to a melanoma antigen, PRAME. Our present study demonstrated that FRAME was mark edly expressed in primary leukemic cells with chronic myeloid leukemia (CML ) in blastic crisis and Philadelphia (Ph)(+)-acute lymphoblastic leukemia ( ALL), in which BCR/ABL played an important role as a pathogenic gene. Moreo ver, comparison of FRAME expression among CD34(+) cells with CML in blastic , accelerated, and chronic phases revealed a higher expression in CML in ad vanced phases. Thus FRAME was considered to be a good candidate for a marke r of Ph+-leukemic blast cells as well as a new target antigen of leukemic b last cells that cytotoxic T cells can recognize. (C) 2000 Federation of Eur opean Biochemical Societies.