Immunocytochemical identification of nuclear estrogen-receptors in human acute myeloid leukemia

The peripheral and bone marrow blast cells of twenty patients newly-diagnosed as acute myeloid leukemia (AML), subtypes M1-M5, were analysed for the presence of estrogen-receptors by ER-ICA immunocytochemistry and dextran-coated charcoal cytosolic (DCC) assay. Two patients demonstrated myeloblasts with nuclear staining patterns consistent with the presence of estrogen-receptors. The positive immuno-staining results were confirmed by DCC in one patient with AML, subtype M4. This patient demonstrated an unusual myeloblast karyotype with a reciprocal translocation t(6;11)(q27;q23.3) involving the designated locus of the ESR gene on chromosome 6 (6q24-qter). The abnormal juxtaposition of DNA control elements close to the promoter of the ESR gene may be one mechanism by which aberrant synthesis of estrogen-receptor protein can occur to provide a growth advantage for leukemia cell clones.