Acute monocytic leukemia with (8;22)(p11;q13) translocation Involvement of 8p11 as in classical t(8;16)(p11;p13)

A new case of acute monocytic leukemia observed in a 73-year-old male (ANLLM5) with an unusual t(8;22)(p11;q13) is reported. The blasts did not demonstrate erythrophagocytosis, but the presence of both naphtol-ASD-chloro-acetate esterase and butyrate esterase activities was similar to that seen in cases with t(8;16)(p11;p13). Involvement of the 8p11 region in ANLLM4 and M5 is discussed, being the third most frequent rearrangement in acute leukemia with monocytic components seen at our Center.     

Translocation (11;16)(q23;p13) acute myelogenous leukemia and myelodysplastic syndrome

The purpose of this study is to examine the relationship of t(11;16)(q23;p13) to the type of myeloproliferative disorder noted by hematopathology. Previously, t(11;16) has been reported in fewer than 20 patients, all with the diagnosis of therapy-related (secondary) acute myelogenous leukemia (sAML) or myelodysplastic syndrome (MDS). Putative involved genes are the MLL on 11q23 and CBP at 16p13. Data from The University of Texas M. D. Anderson Cancer Center (UTMDACC) Cytogenetics Laboratory revealed 3 patients with t(11;16) observed during the past 5 years. Two of the patients had a prior diagnosis of non-Hodgkin lymphoma (NHL) and had been treated with chemotherapy, which included cyclophosphamide. The other patient presented with de novo AML and no history of cancer or chemotherapy. Two of the 3 patients had t(11;16) as the sole cytogenetic abnormality. One patient had a t(11;16) clone that included t(9;21) and t(10;21) as additional changes. Translocation (11;16) has previously been reported only as being therapy-related. In this study, the t(11;16) was seen in 2 patients with previous lymphomas treated with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP). A single patient with apparently de novo AML constitutes the first reported instance of non-treatment associated t(11;16) AML.     

Translocation (11;19)(q23;p13.3) associated with a novel t(5;16) (q13;q22) in a patient with acute myelocytic leukemia

A novel association of t(11;19)(q23;p13) and t(5;16)(q13;q22) was detected by G-banding and spectral karyotyping studies in an 18-year-old patient. While balanced t(11;19) has been often described in acute myelocytic leukemia (AML) French-American-British Cooperative Group subtypes M4 and M5, this patient was diagnosed with the variant AML-M4 with eosinophilia (AML-M4Eo), which is associated with abnormalities in 16q22 and has good prognosis. However, the patient relapsed after allogeneic transplant and died within 2 years of diagnosis, which suggests that the association of these two translocations correlates with a poor prognosis. This report expands the molecular basis of the variability in clinical outcomes and adds the novel t(5;16)(q13;q22) to the spectrum of chromosome 16q22 abnormalities in AML.     

t(10;16)(q22;p13) and MORF-CREBBP fusion is a recurrent event in acute myeloid leukemia

Recently, it was shown that t(10;16)(q22;p13) fuses the MORF and CREBBP genes in a case of childhood acute myeloid leukemia (AML) M5a, with a complex karyotype containing other rearrangements. Here, we report a new case with the MORF-CREBBP fusion in an 84-year-old patient diagnosed with AML M5b, in which the t(10;16)(q22;p13) was the only cytogenetic aberration. This supports that this is a recurrent pathogenic translocation in AML.     

Chronic myelomonocytic leukemia with t(7;11)(p15;p15) and NUP98/HOXA9 fusion

We have recently cloned the inv(8)(p11q13) in a patient with acute myeloid leukemia (AML), and demonstrated a fusion between the MOZ and TIF2 genes at 8p11 and 8q13, respectively. We have partially characterized a further case of AML with the same karyotypic abnormality. Rearrangements were detected by Southern blotting with a TIF2 probe that was close to the breakpoint in the original inv(8) case and with a MOZ probe corresponding to the breakpoint cluster region in the t(8;16) (p11;p13). These findings indicate the existence of breakpoint cluster regions within both genes and demonstrate that the MOZ-TIF2 fusion is consistently associated with the inv(8)(p11q13).     

Translocation t(8;16)(p11;p13) in acute nonlymphoblastic leukemia (M4) possibly secondary to Hodgkin's disease

Simultaneous involvement of bands 8p11 and 16p13 in a primary, even though rare, chromosomal translocation recently described in acute nonlymphocytic leukemia may be of crucial interest in some subtypes of this acute leukemia, particularly in the monocytic form. In the present report we describe this translocation in acute nonlymphoblastic leukemia FAB M4, possibly secondary to Hodgkin's disease, though it is also possible that the leukemia may have developed de novo. The aberration t(8;16)(p11;p13) was present in 100% of direct and cultured bone marrow cell preparations. A very high frequency of cells with nonclonal structural chromosome aberrations was also observed in peripheral blood cultures (more than 53%). Random translocations and deletions constituted most of the observed alterations. These findings are discussed with regard to the relationships between secondary leukemias and intensive polychemotherapeutic treatments of primary neoplasias.     

Translocation (1;11)(q23;p15), a novel simple variant of translocation (7;11)(p15;p15), in a patient with AML (M2) accompanied by non-Hodgkin lymphoma and gastric cancer

We describe a case of an acute myelogenous leukemia (AML) associated with t(1;11) (q23;p15), which is a novel simple variant translocation of t(7;11)(p15;p15). The patient was a Japanese man who had a history of non-Hodgkin lymphoma (NHL) and received MACOP-B combination chemotherapy. Fifteen months after the completion of the treatment, the patient developed AML (M2), which was regarded as a therapy-related leukemia. Cytogenetic study of bone marrow cells showed t(1;11). Although he achieved complete remission by combination chemotherapy, a relapse of NHL and gastric cancer were revealed in the course of the consolidation chemotherapy for AML. The NHL was considered a histological conversion from follicular lymphoma because lymphoma cells carried t(14;18) (q32;q21) and were strongly positive for BCL2 protein. Translocation (1;11), together with AML having t(7;11) or inv(11) involving 11p15, shows that 11p15 is a common acceptor site of these chromosome aberrations and suggests the significance of the NUP98 gene located in 11p15 in therapy-related leukemia.     

Characterization of a t(8;13)(p11;q11-12) in an atypical myeloproliferative disorder

Fourteen cases of an atypical myeloproliferative disorder associated with consistent translocations involving 8p11-12 have previously been described. A t(8;13)(p11;q11-12) was the most common, but variant t(8;9)(p11-12;q32-34) and t(6;8)(q27;p12) were also reported. Here we have used a series of yeast artificial chromosomes (YACs) derived from the 8p11 and 13q11-12 regions to analyse one of the t(8;13) cases by fluorescence in situ hybridization (FISH). YACs flanking the 13q11-12 breakpoint and spanning the 8p11 breakpoint have been isolated. These YACs will facilitate characterization of the genes involved in this rearrangement. Genes Chromosomes Cancer 21:70–73, 1998. © 1998 Wiley-Liss, Inc.     

A case of inv(8)(p11q24) associated with acute myeloid leukemia involves the MOZ and CBP genes in a masked t(8;16).

We report on a novel chromosomal aberration, inv(8)(p11q24), in an M5 acute myeloid leukemia. We show by fluorescence in situ hybridization and Southern blot analyses that a t(8;16)(p11;p13) is masked by this inversion. The translocation targets the MOZ gene from the 8p11 and the CBP gene from the 16p13 chromosomal regions. The breakpoints occur in the MOZ region encoding the acidic domain and in the 5' end of the CBP gene. These results provide further evidence for the multiple contribution of both MOZ and CBP genes in acute leukemias. Genes Chromosomes Cancer 26:161-165, 1999.     

inv(16)(p13q22) in chronic myelogenous leukemia in blast phase: a clinicopathologic, cytogenetic, and molecular study of five cases

Blast phase (BP) in chronic myelogenous leukemia (CML) frequently is accompanied by cytogenetic abnormalities in addition to t(9;22)(q34;q11.2). We describe 5 patients with CML in blast phase (CML-BP) in which t(9;22) and inv(16)(p13q22) were identified by conventional cytogenetics, with confirmation of BCR-ABL and CBFss-MYH11 by fluorescence in situ hybridization. The morphologic findings at the time of BP resembled de novo acute myeloid leukemia (AML) carrying inv(16)(p13q22), with abnormal eosinophils in the bone marrow and monocytosis in the peripheral blood in all cases. In 1 patient, inv(16)(p13q22) and abnormal eosinophils were detected in the bone marrow 2 months before CML-BP. The clinical course of these patients was similar to patients with CML-BP without evidence of inv(16)(p13q22). These cases illustrate that inv(16)(p13q22) is a form of cytogenetic evolution that rarely occurs in patients with CML at the time of BP. In this setting, unlike de novo AML, inv(16)(p13q22) in CML-BP is not associated with a favorable prognosis.     

Genomic characterization of MOZ/CBP and CBP/MOZ chimeras in acute myeloid leukemia suggests the involvement of a damage-repair mechanism in the origin of the t(8;16)(p11;p13)

The t(8;16)(p11;p13), which is strongly associated with acute myeloid leukemia (AML) displaying monocytic differentiation, erythrophagocytosis by the leukemic cells, and a poor response to chemotherapy, fuses the MOZ gene (8p11) with the CBP gene (16p13). Although genomic rearrangements of MOZ and CBP have been detected using fluorescence in situ hybridization and Southern blot analyses, characterization of the breakpoints at the sequence level has never been performed. We have sequenced the breakpoints in four t(8;16)-positive AML cases with the aim to identify molecular genetic mechanisms underlying the origin of this translocation. In addition, an exon/intron map of the MOZ gene was constructed, which was found to be composed of 17 exons. Long-range-PCR with CBP forward primers in exon 2 and MOZ reverse primers in exon 17 as well as with a MOZ forward primer in exon 16 and a CBP reverse primer in intron 2 successfully amplified CBP/MOZ and MOZ/CBP hybrid genomic DNA fragments in all four AMLs. The breaks clustered in both CBP intron 2 and MOZ intron 16, and were close to repetitive elements, and in one case an Alu-Alu junction for the CBP/MOZ hybrid was identified. Additional genomic events (i.e., deletions, duplications, and insertions) in the breakpoint regions in both the MOZ and CBP genes were found in all four cases. Thus, the t(8;16) does not originate through a simple end-to-end fusion. The findings of multiple breaks and rearrangements rather suggest the involvement of a damage-repair mechanism in the origin of this translocation.     

Translocation t(8;13)(p11;q11-12) in stem cell leukemia/lymphoma of t-cell and myeloid lineages

An unusual hematologic neoplasia has been described recently in which the predominant clinical features include T-cell lymphoma, myeloid hyperplasia, and eosinophilia. The multilineage involvement in this disorder suggests transformation of a primitive stem cell. Abnormal karyotypes have been described in three such cases, including one case with t(8;13)(p11.2;q12) and a second case with t(8;13)(p23;q14). We report translocation of chromosomes 8 and 13 in lymph node karyotypes from two patients with this syndrome. Fluorescence in situ hybridization confirmed an identical translocation, t(8;13)(p11;q11-12), in lymphoma cells from each patient. The translocation breakpoints are of particular interest because the FLT3 receptor tyrosine kinase gene has been mapped to 13q12. FLT3 is expressed highly in hematopoietic progenitor cells and in myeloid and lymphoid acute leukemias.