Identification of Nine Chromosomal Segments with Jumping Translocation in 564 Human Leukemia and Lymphomas

Abstract

In order to identify the chromosome regions with segmental jumping translocation (SJT) that will be associated with gene amplification, 564 leukemia, malignant lymphoma and other hematological disease patients with highly complex karyotype were studied by both inter-phase and metaphase fluorescent in situ hybridization (FISH). Specific chromosome regions translocated onto structurally abnormal chromosomes, resulting in partial tri-, tetra-, or pentasomy of these regions. These SJTs were found in 9 chromosomal segments such as 8q24, 9q34, 11q13, 11q23, 13q14, 14q24-q32, 17p12, 21q22 and 22q11 indicating that SJT is not rare cytogenetic events in leukemia and lymphoma with complex chromosome aberrations. SJT at 8q24, 11q13, 14q24-32 and 21q22 were predominantly detected in 17.6% of AML, 46.1% of non-Hodgkin's lymphoma (NHL), 29.6% of acute type of adult T-cell leukemia and 16.6% of AML. In total, 10.7% of 564 leukemia and lymphoma patients, including 43 analyzed patients on no SJTs at 5q34 and 20q11.2 had either one or two of the 9 SJTs. 3-7 copies of SJTs per a metaphase were observed at 11q13 and 11q23. Protein expression levels of MYC were well correlated with amplified MYC signals in NHL patients. The SJT provides evidence of mechanism for formation of unidentified marker chromosomes as well as for the development of the advanced disease stage.