Loss of a Hu-ets-1 allele in human leukemia cell lines ML-1, -2, and -3 with a chromosome change at 11q24.

The ML cell lines (ML-1, -2, and -3) were derived from the cells of a patient with T-cell malignant lymphoma who developed acute myeloblastic leukemia and whose cells showed a primary chromosome change at band 11q24. Surface marker studies of the ML cells showed that they had both myeloid (MCS-1, MCS-2, and OKM-1) and some T-lymphocyte (3A1/Leu-9 and OKT-4/Leu-3a) characteristics. Molecular studies on these lines were performed in order to determine the possible involvement of the Hu-ets-1 gene, since it is located at band 11q23----q24. All ML cell lines showed half the intensity of the Hu-ets-1 DNA bands as compared to those of controls (karyotypically normal B-cell lines). In contrast, DNAs from leukemia cells with t(4;11)(q21;q23) or t(1;11)(q21;q23 or q24) showed no rearrangement, deletion, or amplification of the ets-1 gene. These findings indicate that a chromosome region (11q24----qter), including the Hu-ets-1 gene, of the ML cells is deleted as a result of the primary cytogenetic change and that heterogeneity is present in the mechanism of human leukemia involving the 11q23----q24 region.