A translocation t(9;11)(p11;q23) in T-cell acute lymphoblastic leukemia (FAB-l2)

We here report a t(9;11)(p11;q23) as the only abnormality in the affected cells of a 20-year-old male with acute lymphoblastic leukemia (L2) of T-cell origin. One hundred six patients with acute leukemia and involvement of band 11q23 were reviewed. Young age, hyperleukocytosis, and poor prognosis characterized almost all the cases in the acute leukemias with the 11q23 translocation, despite involvement of different recipient chromosomes and different morphologic and immunologic phenotypes.     

Reciprocal translocation (11;19)(q23;p13) in congenital acute lymphoblastic leukemia

The cytogenetic, clinical, and immunologic findings ina 4-month-old girl with acute lymphoblastic leukemia (ALL) are reported. The malignant lymphoblasts were characterized cytogenetically by the reciprocal translocation t(11;19)(q23;p13); immunologically by an immature pre-B-ALL phenotype. In spite of the high-risk nature of the leukemia, the patient attained complete remission relatively quickly and is still free of disease 3 years after diagnosis. Because the only two previously reported ALL patients with t(11;19) also seem to have responded well to therapy, this cytogenetic abnormality might turn out to be an indicator of favorable prognosis in ALL.     

A variant t(X;15)(p11;q22) translocation in acute promyelocytic leukemia

Nonrandom reciprocal translocations involving chromosomes #15 and #17 are characteristic anomalies in a great majority of cases of acute promyelocytic leukemia (APL). Other complex translocations in APL that invariably involve chromosome #17 also have been described. We describe a patient with clinical and morphologic characteristics of APL but with a previously undescribed acquired karyotype, t(X;15)(p11;q22). This is the first translocation in APL described in which chromosome #17 is not involved. Although a comparative structure/function analysis of potentially relevant genes to the translocation breakpoints in both t(X;15) and t(15;17) APL showed no major alterations, the enhanced expression of the c-Ki-ras oncogene observed in t(X;15) APL supports the concept of heterogeneity in APL at the cytogenetic and molecular levels.     

A complex genetic rearrangement in a t(10;14)(q24;q11) associated with T-cell acute lymphoblastic leukemia.

The t(10;14)(q24;q11) is observed in the leukemia cells of 5-10% of cases of T-cell acute lymphoblastic leukemia (T-ALL). Recently, molecular analyses of a number of these translocations revealed simple reciprocal translocations between the T-cell receptor delta chain gene (TCRD) and a region of 10q24. We have characterized, at the molecular level, a t(10;14)(q24;q11) in a patient with T-ALL. The translocation in this case, in contrast to the previous cases, is part of a complex genetic rearrangement. In addition to a reciprocal translocation between the D delta 3 gene segment of TCRD and a region of 10q24, a local inversion occurred within TCRD, involving the D delta 2 and V delta 2 gene segments. As a consequence, the entire joining and constant regions and most of the diversity regions of TCRD are located on the derivative 14 chromosome, whereas the joining and constant regions of TCRA are positioned on the derivative 10 chromosome. The chromosome 10 breakpoint in our patient, as in other t(10;14), clusters within a 9 kb breakpoint region. The occurrence of seven breakpoints within a localized region of chromosome 10 implies the existence of a nearby gene whose activation may have conferred a selective advantage on the leukemia cells. Moreover, as in the previous cases, the translocation in the present study exhibits recombination signal sequences or signal-like sequences adjacent to the breakpoint junction. The presence of such motifs suggests the involvement of the recombinase enzyme system in the generation of this genetic alteration.     

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.     

A der(1;15)(q10;q10) is a rare nonrandom whole-arm translocation in patients with acute lymphoblastic leukemia

A rare karyotypic event, der(1;15)(q10;q10), which involves the whole long arms of chromosomes 1 and 15, has been reported in patients with various conditions, including acute myelogenous leukemia, myelodysplastic syndrome, polycythemia vera, and multiple myeloma. Only 27 cases of unbalanced der(1;15)(q10;q10) have been documented in the literature as single or complexed chromosomal abnormalities in hematological malignancies. Here, we describe two cases of acute lymphoblastic leukemia with der(1;15)(q10;q10), and review the previous reports. Although more case studies are needed, we suggest that der(1;15)(q10;q10) should be considered a nonrandom chromosomal abnormality in hematological malignancies including both lymphoid and myeloid neoplasms.     

Recurrent translocation t(10;17)(p15;q21) in minimally differentiated acute myeloid leukemia results in ZMYND11/MBTD1 fusion

Pediatric acute myeloid leukemia (AML) is a heterogeneous disease, characterized by different collaborating karyotypic and molecular abnormalities, which are used in risk group stratification. In ～20% of the pediatric AML cases a specific genetic aberration is still unknown. Minimally differentiated myeloid leukemia or FAB‐type M0 is a rare morphological subtype of AML. The translocation t(10;17)(p15;q21) is described to be recurrent in minimally differentiated AML, but the involved genes and location of the breakpoints have so far not been identified. In this study, we show that this translocation results in an in‐frame translocation fusing exon 12 of the tumor suppressor gene ZMYND11 to exon 3 of the chromatin protein MBTD1, encoding a protein of 1,054 amino acids, while the reciprocal fusion product is predicted to lack a productive start codon. Gene expression profiling of the leukemic cells showed high HOXA expression. ZMYND11, also known as BS69, is a tumor suppressor that specifically recognizes H3K36me3, which is linked to aberrant HOXA expression in leukemogenesis. Aberrant expression of the genes involved in this fusion may thus contribute to the HOXA‐phenotype observed with gene expression profiling. © 2015 Wiley Periodicals, Inc.     

CD7+, CD4-/CD8- acute leukemia with t(11;14)(p15;q11) in a child.

A t(11;14)(p15;q11) was the sole chromosome abnormality observed in the malignant cells of a 10-year-old boy with acute leukemia. Morphologically, these cells were classified as L1 by the criteria of the French-American-British Working Group. Cytochemical analysis revealed that the leukemic cells were negative for Sudan Black B, periodic acid Schiff, and esterases, and positive for acid phosphatase. Immunophenotyping disclosed that the cells expressed a very immature antigenic profile [CD34+, CD7+, cytoplasmic CD3+, membrane CD3-, CD4-, and CD8-]. In spite of very intensive chemotherapy, complete remission was never induced, and the child died of progressive disease. The relationship of this case to other reported cases of acute leukemia arising from immature pluripotent hematopoietic cells is discussed.     

B-cell acute lymphoblastic leukemia with tandem t(14;14)(q11;q32).

Translocation (14;14)(q11;q32) was associated with acute lymphoblastic leukemia in a child. The B-cell lineage of the leukemic cells led us to perform FISH studies, which showed that the chromosomal breakpoints were telomeric to TCRA/D and IGH loci. These findings show that FISH analyses are necessary when unusual features are associated with a recurrent translocation.     

Isochromosome (17)(q10) and translocation (4;12)(q12;p13) in a child with acute myeloid leukemia.

Isochromosome 17q is a commonly observed cytogenetic aberration in hematologic malignancies. Isolated isochromosome 17q usually presents as a marker of a chronic myeloid disorder, with a high propensity for transformation into acute nonlymphoblastic leukemia (ANLL). t(4;12)(q11-12;p13) is a recently described translocation, associated with ANLL, predominantly in adults. In this article, we present a case of acute myeloblastic leukemia (AML) in a 14-year-old female in which i(17q) and t(4;12)(q12;p13) were found in the leukemic clone at diagnosis. We briefly review the literature and hypothesize as to the significance of the coexistence of these cytogenetic changes.     

T-cell acute lymphoblastic leukemia with t(1;18)(p36;q22)

An 8-year-old white boy with a T-cell acute lymphoblastic leukemia (T-ALL) developed chromosomal abnormalities t(1;18)(p36;q22) and del (6)(q21) at the first bone marrow relapse. Rearrangements of the chromosome region 1p36 have been reported previously in adults with T-ALL.     

T-cell prolymphocytic leukemia with a novel translocation (6;11)(q21;q23).

T-cell prolymphocytic leukemia (T-PLL) is an uncommon chronic lymphoproliferative disorder characterized by lymphadenopathy, splenomegaly, and lymphocytosis. The leukemic cells have the appearance of prolymphocytes and usually an immunophenotype of T-helper cells (CD3+ CD4+ CD8-). Inv(14q), del(11q), i(8q), and rearranged Xq28 are the commonest nonrandom chromosomal abnormalities in T-PLL. Recently, it has been shown that the ataxia-telangiectasia mutated (ATM) gene located at 11q23 is often deleted in T-PLL, suggesting a tumor suppressor role of the ATM gene on tumorigenesis of T-PLL. We report a case of T-PLL with t(6;11)(q21;q23) as the sole chromosomal abnormality and suggest that the cytogenetically identified translocation also implicates the ATM gene.     

5例伴有t(16;21)(p11;q22)急性白血病的临床和实验研究

目的：报告5例伴有t(16;21)(p11;q22)的急性白血病和其中1例的染色体涂染分析。方法：骨髓细胞24h培养后按常规方法制备染色体，采用R显带技术进行染色体核型分析，并以16号和21号整条染色体涂染探针对其中1例患者进行染色体涂染检测。结果：5例均显示t(16;21)(p11;q22),占15年来进行染色体检查的急性非淋巴细胞白血病患者总数的0．3％（5／1448）。5例均无白血病细胞吞噬其他血细胞现象。1例患者的染色体涂染分析证实了16号和21号染色体之间发生了相互易位。结论：t(16;21)是急性非淋巴细胞白血病中1种少见的非随机的染色体易位，代表了1种独特的白血病亚型。染色体涂染技术是比常规核型分析更为可靠的检测该易位的手段。