Philadelphia-like translocation t(9;22)(q34;q11) found in a follicular lymphoma involving not BCR and ABL but IGL-mediated rearrangement of an unknown gene on 9q34

DOR-1, A novel CD10+ stromal cell line derived from progressive Langerhans cell histiocytosis of bone

BACKGROUND

Langerhans cell histiocytosis (LCH) is granulomatous proliferative disorder characterized by the presence of activated Langerhans cells admixed with macrophages, lymphocytes, and eosinophils. In an effort to obtain an LCH ex vivo model, we succeeded in establishing the DOR-1 cell line from an LCH lesion of bone in a 3-year-old girl.

PROCEDURE

The DOR-1 cell line was established from a CD1a immunoreactive LCH lesion of bone maintained in long-term cell culture. The phenotypic characteristics were assessed by immuno-cytochemistry and fluorescence activated cell sorter (FACS) analysis. Cytogenetic analysis was performed by RHG-banding that was supplemented by fluorescence in situ hybridization (FISH).

RESULTS

The DOR-1 cells grew in vitro as a poorly differentiated mesenchymal-like cells with a doubling time between 72 and 96 hr. The cells exhibited pleomorphism and consistent immuno-reactivity for CD10 (50%), CD13 (55%), CD68 (65%), and CD117 (70%) while CD1a, Langerin and HLA-DR were not detected. By RHG-banding, several aberrant chromosomes were detected including the t (9; 17) (p23; p13) translocation and a pair of long dicentric marker chromosomes indicating clonal abnormality. Functionally, exposure to 33 nM 12-O-tetradecanoyl phorbol mirystate-13-acetate (TPA) induced DOR-1 cell differentiation with appearance of cytoplasmic extensions.

CONCLUSIONS

The DOR-1 cell line exhibits distinct immuno-cytochemical features and carries the t (9; 17) (p23; p13) translocation suggesting involvement of stromal-like cell lineage in LCH initiation and progression.

A t(1;9)(q23.3∼q25;q34) affecting the ABL1 gene in a biphenotypic leukemia

Recurring chromosome translocations, which are found in leukemia, can result in the inappropriate expression of oncogenes or in the formation of chimeric genes that code for structurally and functionally abnormal proteins. The chromosomal t(1;9)(q23.3 approximately q25;q34) was found in a patient with biphenotypic leukemia. Fluorescence in situ hybridization (FISH) analysis revealed that the break on chromosome 9 occurred in the ABL1 gene. The breakpoint on chromosome 1 occurred distal to the PBX1 gene at 1q23.3, as shown by FISH using BAC RP11-503N16 and RP11-403P14, which flank the PBX1 locus; hence, the ABL1 gene can be fused with another gene distal to PBX1 gene.

A t(4;11)(q21;p15) in a case of T-cell lymphoma and a case of acute myelogenous leukemia

The translocation (4;11)(q21;p15) has been observed in acute lymphoblastic as well as acute myeloid leukemias (ALL and AML, respectively). We report the first case of T-cell lymphoma with t(4;11)(q21;p15) and a case of AML. The clinical history of and cytogenetics in the latter is suggestive of a secondary leukemia; his karyotype revealed emergence of a t(3;11)(q21;q13) in addition to the t(4;11). Previously reported cases with t(4;11)(q21;p15) are reviewed, clinical and morphological characteristics of cases with t(4;11)(q21;q23) and t(4;11)(q21;p15) are compared, and chromosome abnormalities involving the NUP98 gene in hematologic malignant disorders are reviewed.

Detection of abundantly transcribed genes and gene translocation in human immunodeficiency virus-associated non-Hodgkin's lymphoma

Several novel, differentially transcribed genes were identified in one centroblastic and one immunoblastic HIV-associated B-cell non-Hodgkin's lymphoma (B-NHL) by subtractive cloning. In both lymphomas, we detected an upregulated transcription of several mitochondrial genes. In the centroblastic B-NHL, we found a high level transcription of nuclear genes including the interferon-inducible gene (INF-ind), the immunoglobulin light chain gene (IgL), the set oncogene, and several unknown genes. The data obtained on upregulated expression of the genes in human B-NHL of HIV-infected patients considerably overlap with those obtained earlier for the B-NHL of simian immunodeficiency virus-infected monkeys. In the centroblastic lymphoma, one transcript revealed a fusion of the 3'-untranslated region of the set gene and the C-terminal region of the IgL gene. This chimeric sequence was confirmed by a site-directed polymerase chain reaction performed with total cDNA and genomic DNA. The expected amplification product was obtained in both cases pointing to a genomic rearrangement. The IgL-set fusion sequence was not found in cDNA preparations and genomic DNA of the immunoblastic HIV-associated B-NHL. Further studies are necessary to determine whether these genes contribute to lymphoma development or can be used as therapeutic targets.