CHARACTERIZATION OF A T(10-11)(P13-14-Q14-21) IN THE MONOBLASTIC CELL-LINE U937

Previous analysis of the monoblastic cell line U937 has shown that sev eral sublines contain a rearranged chromosome arm 11q. In order to det ermine the true nature of the rearrangement, fluorescence in situ hybr idization (FISH) was carried out with various combinations of single c opy anonymous markers, clones containing genes, a chromosome 10 paint, and an 11 centromere specific sequence. The rearrangement was deduced to be a reciprocal translocation between chromosomes 10 and 11 descri bed as t(10;11)(p 13-14;9 14-21). The breakpoint on chromosome 11 is t elomeric to the INT2 gene and the pHS 11 probe at 11 q 13, and centrom eric to the marker D11S36 localized to 11q14.3-q22.1 and the MLL gene at 11q23. Similar translocations have been reported in various acute l eukemias, principally of the monocytic lineage, and also in T-cell pre cursor acute lymphocytic leukemias. Further characterization of the ge netic rearrangements in U937 may lead to the isolation of genes import ant in leukemogenesis and provide an in vitro system for their study. (C) 1995 Wiley-Liss, Inc.