ESTABLISHMENT OF A NOVEL HUMAN MYELOID-LEUKEMIA CELL-LINE (FKH-1) WITH T(6-9)(P23-Q34) AND THE EXPRESSION OF DEK-CAN CHIMERIC TRANSCRIPT

Translocation t(6;9)(p23;q34), resulting in a dek-can gene fusion, is a recurrent chromosomal abnormality mainly associated with specific su btypes of acute myeloid leukaemia (AML) and myelodysplastic syndrome ( MDS). Patients with this type of chromosomal change are usually young and their prognosis is poor. The role of fusion protein generated from dek-can chimaeric transcript on the leukaemogenesis of t(6;9) AML or MDS is as yet unknown. We have established the first permanent cell li ne (FKH-1) with t(6;9), derived from the peripheral blood of a patient with t(6;9) AML transformed from Philadelphia chromosome (Phl)negativ e chronic myelocytic leukaemia (CML). The FKH-1 expressed myelomonocyt ic markers and dek-can chimaeric transcript, In the presence of 10 ng/ ml recombinant human granulocyte colony-stimulating factor (G-CSF), th e cells doubled every 54h and showed multilineage myeloid differentiat ion,; resulting in heterogenous morphologies such as macrophages, baso phils, eosinophils and neutrophils. Thus, this cell line may be derive d from a pluripotent myeloid stem cell and should be a useful tool for biomolecular studies on the pathogenesis of t(6;9) myeloid malignanci es which have rarely been investigated because of the lack of continuo usly proliferating cells.