Cytogenetical and hematological analysis of chronic myelogenous leukemia patients with a novel case 52XX,t (1;9;22) (q23.3; q34; q11.2), +6, +8, i(9) (q10;q10), +18,+19,+21+der22 t(9;22)(q34;q11)

(9;22) (q34; q11) translocation is appear in above ninety percent of chronic myelogenous leukemia patients while variant/complex translocations were observed in almost 5% to 8% chronic myelogenous leukemia (CML) positive cases. Gleevec (Imatinib Mesylate) is the first choice breakpoint cluster region (BCR)/ABL targeted oral therapy that produced a complete response almost in 71% to 80% of patients affected with CML. A complete blood count (CBC) of 37 patients was done during diagnosis, however only 21 showed abnormal CBC values which were selected for the study. Karyotyping study using bone marrow samples was performed on 21 CML patients for the conformation of 9;22, however, fluorescence in situ hybridisation was performed for the detection of the BCR–ABL fusion gene of 15 patients. Out of 21, 17 patients showed Ph-positive (9;22) (q34; q11) translocation. Sixteen CML patients showed standard translocation however only CML patients showed a three-way variant/complex translocation with six additional chromosomes, 52XX, t(1;9;22) (q23.3;q34;q11),+6,+8, i(9)(q10;q10), +18,+19,+21 + der22 t(9;22)(q34;q11)). Here we report we report a novel case of six additional chromosomes with the three-way translocation of 52XX, t(1;9;22) (q23.3;q34;q11),+6,+8, i(9)(q10;q10), +18,+19,+21 + der22 t(9;22)(q34;q11) in blast phase.     

t(14;22)(q32;q11) in non-Hodgkin lymphoma and myeloid leukaemia: molecular cytogenetic investigations

Two non-Hodgkin lymphomas (NHL), one chronic lymphocytic leukaemia/small lymphocytic lymphoma and one diffuse large B-cell lymphoma and three cases of myeloid leukaemia, two chronic (CML) and one acute (AML), showed, by G-banding analysis, apparently identical chromosomal translocations t(14;22)(q32;q11), in three of the cases as the sole abnormality. Fluorescence in situ hybridisation (FISH) analysis with locus-specific probes for ABL at 9q34 [bacterial artificial chromosomes (BACs) 835J22 and 1132H12], IGH at 14q32 [P1 artificial chromosome (PAC) 998D24] and IGL (PAC 1019H10) and BCR (BAC 74M14) at 22q11, as well as multicolour in situ hybridisation (M-FISH) analyses were performed. A three-way variant translocation of the classical t(9;22)(q34;q11), t(9;22;14)(q34;q11;q32), involving both BCR and ABL, was unravelled by the molecular cytogenetic investigations in the three myeloid leukaemia cases; a similar variant translocation has previously been reported in seven CML. The two cases of NHL (one NHL with a similar 14;22-translocation has been reported previously) had no involvement of BCR or ABL, but instead the IGH and IGL genes were shown to be juxtaposed by the t(14;22)(q32;q11). How such a rearrangement with recombination of IGH and IGL might elicit a pathogenetic effect is completely unknown.     

Establishment of a myeloid leukaemia cell line (Kasumi-4) with t(9;22;11)(q34;q11;q13), inv(3)(q21q26) and the EVI1 gene activation from a patient with chronic myelogenous leukaemia in blast crisis

A novel human leukaemia cell line (Kasumi-4) was established from the peripheral blood of a 6-year-old girl suffering from chronic myelogenous leukaemia (CML) in blast crisis. The Kasumi-4 cells had the following characteristic features: undifferentiated blasts which were positive for CD34, CD33 and CD13 surface markers, but negative for myeloperoxidase platelet peroxidase, CD36, CD41 and CD42; chromosome abnormalities of t(9;22;11) (q34;q11;q13), inv(3)(q21q26); and elevated expression of EVI1 gene which is located at chromosome band 3q26. Megakaryocytic maturation was not observed in the liquid culture following the addition of TPA, IL-3, IL-6 or GM-CSF. b2-a2 type of BCR-ABL chimaeric messenger RNA was detected by RT-PCR analysis. This is the first leukaemia cell line with a three-way translocation containing the Ph chromosome and the second cell line with an inv(3)(q21q26). This cell line appears to be useful for studying the mechanisms of leukaemogenesis involving these chromosomal abnormalities and related oncogenes.     

B-Lymphoid and myeloid lineages biphenotypic acute leukemia with t(8;21)(q22;q22)

By analyzing the characteristics of morphology, immune phenotype, chromosome karyotype and clinical manifestations of six cases of B-lymphoid and myeloid lineages biphenotypic acute leukemia (BAL) with t(8;21)(q22;q22), a new subgroup of BAL was reported. Bone marrow eosinophilia (more than 5%) and pseudo-Chediak abnormalities were not found. Auer rods were also not identified in four of six cases. Immunophenotype revealed B-lymphoid and myeloid lineages positive, together with frequent and high expression of CD34 and CD33, and weak expression of HLA-DR. In addition to t(8;21) chromosomal translocation, deletion of Y chromosome and complex chromosome abnormalities were also found. Chemotherapy for myeloid and lymphoid leukemia simultaneously produced good response in the patients. BAL with t(8; 21)(q22; q22) might be a new subgroup of BAL, and it was suggested that the leukemia clone with t(8;21)(q22;q22) might have originated from an early phase of hematopoiesis, and AML1/ETO fusion gene might be related to differentiation of B lymphocyte.     

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.     

t(1;2), inv(1) and trisomy 1q during the blastic phase of Philadelphia chromosome-positive chronic myeloid leukemia

Several karyotype changes observed during the blastic phase in 2 patients with Philadelphia chromosome (Ph)-positive chronic myeloid leukemia (CML) are reported. Rearrangements involving chromosome 1, i.e., translocations, a pericentric inversion and trisomies of its long arm, are described. In the first patient whose chronic phase was very long (17 years), the uncommon association between i(17q) and Ph duplication has been observed during the blastic phase, beside the involvement of chromosome 1. In the second patient, additional abnormalities involving chromosomes 1, 2, 4, 8, 18 and 21 were present. Of particular interest is the finding of a t(1;2). In this case, the presence of hyperdiploid cells with 49-50 chromosomes, prevailing at the blastic crisis, was due to the evolution of the hypodiploid clone with the 45,XX,t(9;22),-21 karyotype found during the chronic phase. The occurrence of chromosomal changes involving chromosome 1 during the blastic phase of CML is emphasized.     

New Translocations in Chronic Granulocytic Leukaemia: t(X;22) (p22;q11) and t(15;22) (q26;q11)

Two cases of Ph1-positive chronic granulocytic leukaemia with hitherto undescribed translocations are presented. In case 1 the deleted part of chromosome number 22q- was translocated to the short arm of the X chromosome, t(X;22)(p22;q11). Pronounced basophilia, trisomy 19 in the majority of metaphases, and a partial cytogenetic normalization of the bone marrow during busulphan induced remission were additional remarkable features of this case. In case 2 a translocation t(15;22)(q26;q11) was found. In this case the disease was characterized by an increase of unusually small megakaryocytes, thrombocytosis, and an accelerated course.     

Therapy-related acute promyelocytic leukemia with a t(9;22)(q34;q11) and t(15;17)(q22;q11 to approximately 12) subclone

The translocation (15;17) is a typical marker of acute promyelocytic leukemia, whereas t(9;22) is predominantly associated with chronic myelogenous leukemia, and seldom with acute myelogenous leukemia. Furthermore, the association between t(15;17) and t(9;22) in the same cell is extremely rare. We present a case of therapy-related acute promyelocytic leukemia (t-APL) with a subclone accompanied by karyotype 46, XX, t(9; 22)(q34;q11), t(15 ;17)(q22;11 to approximately 12) at onset. A 75-year-old woman was diagnosed as having non-Hodgkin lymphoma of the thyroid gland in July 1997. She was treated with a CHOP-like regimen, but complete remission (CR) was not achieved. She then underwent surgical resection of her thyroid gland, and was treated with etoposide (total dose 16775 mg) from February 1998 to May 2000. In June 2000, having developed t-APL, she was referred to our department. The patient attained CR following treatment with chemotherapy containing all-trans retinoic acid. Ten months later she relapsed, but lost the t(9;22), while maintaining the t(15;17).     

Cytogenetic heterogeneity in blast crisis (BC) of chronic myelogenous leukemia (CML)

Summary New cytogenetic findings are reported in a patient who entered into an accelerated blastic phase of chronic myelogenous leukemia (CML). The cytogenetic findings of this case can be described as 46, xy, t (5; 7) (q31; q11), t (9; 22) (q34; q11), Ph'. The prognostic implications in such patients with rare and unusual cytogenetic findings are discussed.