CD22ΔE12 has emerged as a driver lesion in the pathogenesis of pediatric B-lineage acute lymphoblastic leukemia (ALL) and a new molecular target for RNA therapeutics. Here we report a 43-gene CD22ΔE12 signature transcriptome that shows a striking representation in primary human leukemia cells from patients with relapsed BPL. Our data uniquely indicate that CD22ΔE12 is a candidate driver lesion ...

Development of mammalian B-lineage cells is characterized by progression through a series of checkpoints defined primarily by rearrangement and expression of immunoglobulin genes. Progression through these checkpoints is also influenced by stromal cells in the microenvironment of the primary tissues wherein B-cell development occurs, ie, fetal liver and bone marrow and adult bone marrow. This r...

To identify genes whose expression correlated with biological features of childhood leukemia, we prospectively analyzed the expression profiles of 4608 genes using cDNA microarrays in 51 freshly processed bone marrow samples from children with acute leukemia, over a 24-month period, at a single institution. Two supervised methods of analysis were used to identify the 20 best discriminating gene...

To characterize the biology and optimal therapy of acute mixed-lineage leukemia in children, we reviewed the pathologic and clinical features, including response to therapy, of 35 patients with mixed-lineage leukemia. The majority of cases (91%) had blasts cells that simultaneously expressed either T-lineage plus myeloid markers (T/myeloid, n = 20) or B-lineage plus myeloid markers (B/myeloid, ...

Blast cells from 20 patients with acute leukemia (13 diagnosed myeloblastic and 7 as lymphoblastic, using the FAB classification) were studied using antibodies to lineage-specific differentiation markers. The phenotypic findings were usually consistent with the clinical diagnosis. However, examples were encountered where individual blast cells had a cytoplasmic marker of one lineage and a surfa...

background: acute lymphoblastic leukemia (all) is the most common form of childhood cancer leading to cancer-related death in children. most infants with all harbor recurring structural chromosomal rearrangements that are important initiating events in leukemogenesis but are insufficient to explain the biology and heterogeneity of the disease. mixed-lineage leukemia-rearrangement (mll-rearrange...

Lineage switch is a rare phenomenon in which acute leukemia transforms from lymphoid to myeloid lineage, or vice versa. It is typically seen following therapy or at the time of relapse. Among the chromosomal aberrations associated with lineage switch, the t(4;11)(q21;q23) rearrangement with KMT2A/AFF1 fusion protein (formerly, MLL/AFF1 or MLL/AF4) is the most common. In general, lineage switch ...

INTRODUCTION Treatment of chronic lymphocytic leukemia of the B-cell-lineage is strongly based upon clinical staging because of the heterogeneous clinical course of this disease. CASE PRESENTATION We describe a 62-year-old patient with newly diagnosed chronic lymphocytic leukemia of the B-cell-lineage who did not respond to several chemotherapy regimens including chlorambucil, fludarabine and...

background: acute leukemias are characterized by neoplastic proliferation of hematopoietic stem cells and accumulation of blasts and immature cells in the bone marrow. we applied a selective panel of immunohistochemical markers on bone marrow trephine tissue sections and observed their utility in diagnosis and typing of acute leukemia. materials and methods: the study was done at psg institute ...