t(7;11)(p15;p15) Chronic myeloid leukaemia developed into blastic transformation showing a novel NUP98/HOXA11 fusion

We encountered a patient with Philadelphia-negative chronic myeloid leukaemia, with t(7;11)(p15;p15), in whom acute leukaemia phase (acute myeloid leukaemia-M2 morphology) developed within a short period. We detected a novel gene fusion between NUP98 and HOXA11 both in the chronic phase and in the acute leukaemia phase in this case. Although it is well known that a fusion of NUP98-HOXA9 in myeloid malignancies is created by the t(7;11)(p15;p15), this case suggests the possibility that HOXA11 might be another partner gene for NUP98 in t(7;11)(p15;p15) leukaemia.     

t(4;11)(q21;p15) translocation involving NUP98 and RAP1GDS1 genes: characterization of a new subset of T acute lymphoblastic leukaemia

Two cases of T acute lymphoblastic leukaemia (T-ALL) with an identical t(4;11)(q21;p15) translocation were identified within a prospective study on the biological and clinical features of adult ALL patients enrolled into the therapeutic protocol ALL0496 of the GIMEMA Italian Group. In both cases, the molecular characterization showed an involvement of the NUP98 gene on 11p15 which rearranges with the RAP1GDS1 gene on 4q21. The morphological and immunological features of the leukaemic cells, as well as the clinical behaviour and response to induction therapy, were the same in both patients. Based on the available data, the t(4;11)(q21;p15) translocation involving the NUP98-RAP1GDS1 fusion gene emerges as a new highly specific genetic abnormality that characterizes a subset of T-ALL.     

Additional acquisition of t(1;21)(p32;q22) in a patient relapsing with acute myelogenous leukemia with NUP98-HOXA9

We report a 29-year-old Japanese male with acute myelogenous leukemia (AML)-M4 with a cryptic t(7;11)(p15;p15), in which a chimeric NUP98-HOXA9 fusion was detected by polymerase chain reaction analysis and a chromosomal analysis showed 46,XY. The patient received intensive chemotherapy and underwent autologous stem cell transplantation, and remission was confirmed by the disappearance of NUP98-HOXA9. However, 6 months after transplantation, the patient relapsed; NUP98-HOXA9 was detected again and karyotypic analysis revealed 46,XY, t(1;21)(p32;q22). Fluorescent in situ hybridization (FISH) analysis using an AML1-ETO translocation dual probe, showed that the 21q22 breakpoint involved AML1 locus. A retrospective FISH analysis showed that t(1;21) was absent at onset. This is the first reported case with AML who had a cryptic t(7;11)(p15;p15), and additionally acquired t(1;21)(p32;q22) at relapse.     

Involvement of the NUP98 Gene in a Chromosomal Translocation t(11;20)(p15;q11.2) in a Patient With Acute Monocytic Leukemia (FAB-M5b)

We report here a case of acute monocytic leukemia (M5b subtype according to the French-American-British [FAB] classification) with chromosomal translocation t(11;20)(p15;q11.2). Fluorescence in situ hybridization analysis with a probe for the NUP98 gene, which is located at chromosome band 11p15, showed that the probe hybridized to both derivative chromosomes 11 and 20 as well as to the remaining normal chromosome 11, indicating that the NUP98 gene was split and involved in this translocation. This is the first report of t(11;20)(p15;q11.2) involving the NUP98 gene in overt leukemia.     

Incidence and implication of additional chromosome aberrations in acute promyelocytic leukaemia with translocation t(15;17)(q22;q21): a report on 50 patients

Acute promyelocytic leukaemia (APL) is characterized by the translocation t(15;17)(q22;q21). Usually t(15;17) is the sole cytogenetic abnormality, but some patients show other chromosome aberrations in addition to t(15;17). The influence of additional chromosome aberrations on the clinical outcome of patients with t(15;17) is unclear. We have analysed 50 cases of APL carrying the translocation t(15;17). Additional chromosome aberrations were observed in 17/47 patients (36%) studied at initial diagnosis and in all three patients studied at relapse. In nine cases (18%) an additional chromosome 8 and in six cases (12%) an isochromosome of the long arm of the derivative chromosome 17 was observed. Various structural rearrangements in addition to t(15;17) were detected in nine patients (18%). Clinical follow-up data were available for 44 patients studied at diagnosis. A complete remission (CR) was achieved in 34 patients (77%). 10 patients (23%) died within 1 month after diagnosis due to infection or bleeding, eight (24%) relapsed within 10–18 months after initial diagnosis. 28 patients are alive 2–93 months after diagnosis (25 in first CR, two in second and one in third CR) (median follow-up 18.5 months). Bone marrow transplantation was performed in six patients (three in first CR, two in second CR, one in third CR), all are alive and in CR. An influence of secondary chromosome anomalies on prognosis was not observed. However, if a higher rate of long-term remission can be reached, specific secondary chromosome aberrations might turn out to be of prognostic value.     

Molecular cloning of the breakpoint of t(11;22)(q23;q11) chromosome translocation in an adult acute myelomonocytic leukaemia

Southern blot analysis with a cDNA probe of MLL indicated that the breakpoint is in a Bam HI 8.3 kb fragment which carries the exon 5–11 of MLL gene in DNA from an adult acute myelomonocytic leukaemia with a t(11;22)(q23;q11) translocation. The structural analysis of the rearranged MLL locus demonstrated that the breakpoint is localized between exon 8 and 9 of MLL locus. The normal counterpart fused to the MLL locus was proved to be derived from chromosome 22q11( AF-22 ) by somatic cell hybrids analysis and FISH. By FISH, AF-22 locus was localized to the region more centromeric to the BCR gene.     

Translocation t(9;22) (p23;q11) in atypical chronic myeloid leukemia (aCML) presenting osteolytic lesions

A 58-year-old man with a 4-month history of atypical chronic myeloid leukemia (aCML), treated with INF-alpha and hydroxyurea, presented with severe localized bone pain with involvement of upper limbs on July 17, 2000. Cytogenetic analysis of peripheral blood cells showed 46,XY,t(9;22)(p23;q11) and no BCR-ABL fusion gene was detected by fluorescence in situ hybridization (FISH). On October 30,2000, x-rays revealed extended destruction of the bilateral proximal upper limbs; pain in the femoral bones appeared in December, and the patient couldn't walk. Roentgenograms taken on January 4, 2001, showed diffuse lytic changes in bilateral femoral bones. On January 23, 2001, fixation of pending fractures in the bilateral femoral bones with an intramedullary rod had produced good results. The infiltration of immature myeloid cells was diagnosed by the histological findings of a bone specimen from the right femur. Because the serum levels of parathyroid hormone (PTH), PTH related protein, and calcitonin were normal, we considered that the bone destruction was caused by the invasion of immature myeloid cells. Four months later, the patient showed a marked increase in peripheral immature granulocytes. A bone marrow specimen showed blastic marrow, and he died of a brain hemorrhage. This report suggests that aCML might cause destructive bone lesions prior to the disease progression. To our knowledge, this is the first published case of aCML in which the chromosomal abnormality t(9;22)(p23;ql 1) was detected.     

Donor Cell-Derived Chronic Myeloproliferative Disease with t(7;11)(p15;p15) after Cord Blood Transplantation in a Patient with Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia

We report a case of donor cell-derived chronic myeloproliferative disease with t(7;11)(p15;p15) occurring after cord blood transplantation (CBT). A 41-year-old man developed precursor B-cell acute lymphoblastic leukemia with a karyotype of 46, XY, t(9;22)(q34;q11) and inv(9)(p11;q13), for which he received CBT from a sex-mismatched donor at the first complete remission of the leukemia. Five months after CBT, gradual neutrophilia of unknown origin developed following the myeloid reconstitution after CBT. Karyotyping of bone marrow cells at 9 months after CBT showed 46, XX, t(7;11)(p15;p15) in 17/20 dividing cells, but neither Philadelphia chromosome (Ph) nor inv(9)(p11;q13) was present. This is the first report of chronic myeloproliferative disease with t(7;11)(p15;p15) that developed in donor cells after CBT. The donor was well-developed and healthy, at least at the time of follow-up, half a year after the birth.     

Heterogeneity in the breakpoints of chromosome 19 among acute leukemia patients with the t(11;19)(q23;p13) translocation

Gene probes for insulin receptor (INSR) and c-ets-1 were hybridized to metaphase cells from three leukemic patients with the t(11;19)(q23;p13) translocation. Patients 1 and 2 were diagnosed as acute lymphocytic leukemia (ALL) (L2), and patient 3, as acute myelogenous leukemia (AML) (M4). The c-ets-1 gene was demonstrated to have translocated from chromosome 11 to the short arm of the rearranged chromosome 19 (19p+) in all three patients. On the other hand, the INSR gene translocated from chromosome 19 to the rearranged chromosome 11 (11q-) in the AML case, but remained on the rearranged chromosome 19 in the two ALL cases. Thus, the breakpoints of chromosome 19 are different among the patients studied, proximal to the INSR gene locus in the AML case and distal in the two ALL cases. Consequently, the c-ets-1 gene and the INSR gene remain separated in the AML case, whereas they become close to each other in the two ALL cases. Rearrangement of these two genes was studied in the two ALL patients, with no positive data being obtained. The results suggest that there may be heterogeneity in the breakpoints of chromosome 19 among the t(11;19)-associated acute leukemias.     

Molecular diagnosis of t(11;14) in mantle cell lymphoma using two-colour interphase fluorescence in situ hybridization

t(11;14) is observed in up to 70% of mantle cell lymphoma (MCL) cases and is therefore an important diagnostic element. In routine practice, detection of t(11;14) by conventional cytogenetic techniques is hindered by the low yield and quality of tumour metaphases. Molecular techniques (Southern blot, PCR) are unable to detect a large number of 11q13 breakpoints due to scattering over distances up to 1 Mb. Using 23 MCL patients with karyotypically determined t(11;14) and eight negative controls, we have devised a two-colour interphase FISH assay for detection of the 14q+ chromosome. We chose an 11q13 probe telomeric to the major 11q13 translocation cluster sites and an IGH probe centromeric of the 14q32 breakpoints. This method detected the translocation in all 23 t(11;14) positive patients, with an overall average of 60% nuclei showing colocalized signals. Widespread application of this technique will constitute an important diagnostic aid in clinical management of MCL patients. Since FISH is a convenient method for retrospective analysis of large numbers of patient specimens, this method should contribute to an accurate estimation of t(11;14) frequency in MCL and other chronic B-cell malignancies and consequently to their better nosological characterization.     

Translocations t(X;14)(q28;q11) and t(Y;14)(q12;q11) in T-cell prolymphocytic leukemia

We report a case of T-cell prolymphocytic leukemia (T-PLL) in a 41-year-old male. Classical cytogenetic, spectral karyotyping (SKY) and fluorescence in situ hybridization (FISH) studies of a blood sample obtained at diagnosis revealed the co-existence of t(X;14)(q28;q11), t(Y;14)(q12;q11) and a ring chromosome derived from i(8)(q10). Immunophenotypic studies revealed involvement of T-cell lineage, with proliferation of CD4(-) CD8+. The co-existence of two translocations involving both sex chromosomes in a case of T-PLL is rare. Chromosomal instability associated with the disease progression may have allowed the emergence of cell clones with translocations involving the sex chromosomes and the ring chromosome observed.