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.     

Acute basophilic leukaemia and translocation t(X;6)(p11;q23)

We report two infants with acute basophilic leukaemia associated with a t(X;6)(p11;q23) as the sole abnormality. Morphologic evidence of basophilic lineage was provided by light and electron microscopy. Both patients also had a similar presentation on diagnosis, characterized by clinical signs consistent with a hyperhistaminaemia syndrome, i.e. urticarian rashes and gastro-intestinal disorders evocative of peptic ulcer. Immunophenotypes differed in the two patients, one expressing CD24, CD13 and CD33, whereas only CD117 was found in the other.
Basophilic acute leukaemia, a rare group among acute leukaemias, might be nonrandomly associated with a specific chromosomal abnormality, t(X;6)(p11;q23). This new entity might also be identifiable by an uncommon clinical presentation and occurrence in infancy.     

Pediatric ALK+ anaplastic large cell lymphoma with t(3;8)(q26.2;q24) translocation and c-myc rearrangement terminating in a leukemic phase

Pediatric ALK-positive anaplastic large cell lymphoma (ALK+ ALCL) is usually associated with a favorable prognosis. ALK+ ALCL associated with a leukemic phase is uncommon, but has been associated with an aggressive clinical course and unfavorable prognosis. Overexpression of c-myc has been shown to be a consistent finding in ALK+, but not ALK-negative ALCL (ALK- ALCL), and the c-myc gene is considered a downstream target of deregulated ALK signaling. We describe a pediatric ALK+ ALCL with a leukemic phase at relapse. Similar to other rare cases described in the literature, it followed an aggressive clinical course despite multiple regimens of chemotherapy and bone marrow transplantation. Lymphoma cells showed aberrant ALK expression and c-myc overexpression. In addition to the characteristic t(2;5)(p23;q35) translocation, a t(3;8)(q26.2;q24) translocation was also present, and c-myc gene rearrangement was confirmed by FISH analysis. The findings in this case demonstrate the association of peripheral blood leukemic involvement and aggressive clinical course, and suggest that other factors, such as c-myc rearrangement, may be responsible for the aggressive clinical behavior in ALK+ ALCL.     

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.     

Chronic myelomonocytic leukaemia with t(8;9)(p11;q34) in childhood: an example of the 8p11 myeloproliferative disorder?

We describe the case of a 10-year-old girl with chronic myelomonocytic leukaemia with the chromosomal translocation t(8;9)(p11;q34), who had developed tonsillar lymphoma as extramedullary involvement at the initial presentation. The cytogenetic study of the cells in both bone marrow and tonsils demonstrated t(8;9)(p11;q34), despite no malignant features in the bone marrow specimens. She developed acute leukaemic transformation 8 months after diagnosis during chemotherapy for lymphoma. Although etoposide reduced the number of blasts, t(8;9)(p11;q34)-bearing cells were not eradicated. Complete remission was obtained following an unrelated bone marrow transplantation. The clinical characteristics of this patient are similar to those of the patients with t(8;9)(p11;q34 or q32) or t(8;13)(p11;q11 or q12) reported previously. The unusual progression of the disease might be associated with the presence of t(8;9)(p11;q34), suggesting a part in the 8p11 myeloproliferative syndrome.     

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.     

Primary cutaneous follicle center lymphoma of the arm with a novel chromosomal translocation t(12;21)(q13;q22): a case report

We report a reciprocal translocation between the long arms of chromosomes 12 and 21, t(12;21)(q13;q22), in a patient with primary cutaneous follicle center lymphoma. Follicle center lymphoma of the skin and follicle center cell lymphoma of the lymph node are morphologically and immunophenotypically very similar. However, the clinical behavior and prognosis of these tumors are different due to the molecular basis of these malignancies. Follicle center cell lymphoma of the lymph node is determined by the presence of a unique translocation between chromosomes 14 and 18, t(14;18)(q32;q21), BCL-2-JH gene rearrangement, that is not present in primary cutaneous follicle center lymphomas. Chromosomal translocations in the primary skin lymphomas have not been previously reported. We hope that our discovery of a new translocation t(12:21)(q13q22) will encourage further investigation into the molecular basis of this translocation and other cytogenetic abnormalities in primary cutaneous B-cell lymphomas.     

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.     

Acute myeloid leukaemia (AML) with t(6;9)(p23;q34) is associated with poor outcome in childhood AML regardless of FLT3‐ITD status: a report from the Children's Oncology Group

Acute myeloid leukaemia (AML) with t(6;9)(p23;q34) is a rare subtype associated with FLT3‐internal tandem duplication (ITD) and poor outcomes. The clinical outcomes of paediatric patients with t(6;9) with and without FLT3‐ITD treated on six consecutive cooperative trails were evaluated. In contrast to patients without t(6;9), those with t(6;9) had a significantly lower complete remission rate, higher relapse rate (RR), and poor overall survival (OS). Within t(6;9) patients, those with and without FLT3‐ITD had an OS of 40% and 27% respectively (P > 0·9), demonstrating that t(6;9) is a high‐risk cytogenetic feature in paediatric AML and its clinical impact is independent of the presence of FLT3‐ITD.     

伴t(5;12)(q31;p13),FIP1L1/PDGFRα阴性慢性嗜酸细胞白血病一例并文献复习

目的 提高对慢性嗜酸细胞白血病(CEL)的认识水平.方法 报告1例伴t(5;12)(q31;p13),FIP1样基因1(FIP1L1)血小板衍化生长因子(PDGFRα)(-)CEL的诊治过程.外周血及胸腔积液细胞的免疫表型采用流式细胞术(FCM)分析,染色体采用G显带分析,FIP1L1/PDGFRα融合基因表达采用RT-PCR技术检测,骨髓、肺及脾组织行常规病理学检查.结果 1例16岁女性患者严重贫血、发热、脾大、血小板减少、嗜酸细胞显著增高,持续22个月.骨髓嗜酸细胞浸润伴纤维化改变;肺和脾组织均呈嗜酸细胞浸润,伴脾栓塞.克隆性染色体异常为t(5;12)(q31;p13),不表达FIP1L1/PDGFRα融合基因.外周血及胸腔积液细胞中除大量嗜酸细胞外,CD3-、CD4-、CD8+异常T淋巴细胞分别占淋巴细胞总数的5.43%和1.66%.患者对羟基脲、泼尼松、干扰素和甲磺酸伊马替尼(400 ms/d共40 d)治疗无效,小剂量阿糖胞苷、米托蒽醌、长春新碱、环磷酰胺、甲氨蝶呤、泼尼松等联合化疗仅有短期效果.患者最终死于心、肺、肝、肾多脏器功能衰竭.结论 本例FIP1L1/PDGFRα(-)CEL符合WHO诊断标准,对多种药物及甲磺酸伊马替尼治疗无效,应在疾病早期尽早争取造血干细胞移植.CD3-、CD4-、CD8+克隆性T细胞异常与CEL发病的关系值得关注.     

A case of myelodysplastic syndrome with erythroid hypoplasia associated with a familial translocation t(3;14)(p21.1;q24.1)

Myelodysplastic syndrome (MDS) with erythroid hypoplasia, a rare form of MDS, has not yet been clearly defined. We report here a 20-year-old woman with severe transfusion-dependent anemia and reticulocytopenia. White blood cells and platelet counts were normal. Bone marrow examination showed a low percentage of erythroid precursors (6%) and a marked dyserythropoiesis and dysmegakaryopoiesis. A diagnosis of MDS (refractory anemia according to the FAB classification) with erythroid hypoplasia was made. Cytogenetic analysis of the bone marrow and peripheral blood revealed a 46,XX,t(3;14)(p21.1;q24.1) translocation, which was confirmed by fluorescence in situ hybridization analysis. This translocation was detected in the apparently healthy younger brother, father, and aunt (father's sister) of the patient. Clonality of T cells in the patient was not confirmed by the polymerase chain reaction and heteroduplex temperature-gradient gel electrophoresis. IgM serology for B19 parvovirus was negative. Other conditions known to be associated with erythroid hypoplasia, such as thymoma, were not present. The patient failed to respond to immunosuppressive therapy (antithymocyte globulin and cyclosporin A). Administration of recombinant human erythropoietin improved her anemia. To our knowledge, this balanced translocation, namely t(3;14)(p21.1;q24.1), which is present both in the patient with MDS with erythroid hypoplasia and in the healthy members of the family, has not been defined previously.     

Latent acute promyelocytic leukemia t(15;17)(q22;q12-21) and sarcoidosis: long-term cohabitation

The association of sarcoidosis with hematological malignancies is a well-known phenomenon. To our knowledge, we report the first case involving sarcoidosis and acute promyelocytic leukemia (APL) t(15;17)(q22;q12-21). The major interest lies in the chronology of the two diseases: the APL demonstrated an unusual smoldering evolution, suggesting that pre-existing sarcoidosis may have a non-fortuitous immunological impact on leukemic clone proliferation.     

Establishment of a new Epstein-Barr virus nuclear antigen-positive B-cell line, BALL-2, with t(8;14) (q24;q32) chromosome abnormality from B-cell acute lymphoblastic leukemia, L2.

A new Epstein-Barr virus nuclear antigen (EBNA)-positive B-cell line, designated BALL-2, was spontaneously established from the peripheral blood of a 14-year-old boy with an EBNA-negative B-cell acute lymphoblastic leukemia (B-ALL), L2 in the French-American-British classification. The BALL-2 cell line grew in suspension with or without forming clumps of cells. The cultured cells exhibited lymphoid morphology with indented or lobulated nuclei, prominent nucleoli, and relatively abundant cytoplasm. Immunologic and cytogenetic studies showed that the BALL-2 cell line expressed the B-cell phenotype, CpIg+, SmIg+, CD19+, CD20+, CD38-, Ia+, and had chromosome translocation, t(8;14) (q24;q32). The same phenotypic and chromosome markers were present in original leukemia cells. These results indicated that the cell line was derived from the patient's leukemia cells. Unexpectedly, however, BALL-2 cells were positive for EBNA and EB virus DNA. Gene analysis of the BALL-2 cell line showed biallelic rearrangements in the JH locus. One of the JH rearrangement comigrated with a rearranged c-myc gene, indicating the translocation had occurred between JH and c-myc loci. The t(8;14) abnormality is a known chromosome marker of Burkitt lymphoma and L3 type ALL. Our studies revealed that this translocation and myc gene rearrangement can also be found in L2 type B-ALL.     

Acute Myelomonocytic Leukemia with Dysplastic Bone Marrow Eosinophils Showing t(5;17)(q13;q11) and a Secondary Chromosomal Aberration, inv(16)(p13q22)

inv(16)(p13q22) is associated with de novo acute myelomonocytic leukemia with dysplastic bone marrow eosinophils (AMML Eo), which has a relatively favorable clinical course with a longer remission duration and better survival prospects. On the other hand, t(5; 17)(q13;q11), although relatively rare, has been reported to be a component of complex chromosomal abnormalities in myelodysplastic syndromes and secondary acute myeloid leukemia (AML). We treated a 29-year-old woman with the first reported case of de novo AMML Eo with inv(16)(p13q22) in addition to t(5; 17)(q13;q11). Although she attained complete remission (CR) immediately after induction therapy, the disease recurred 1 year after the completion of consolidation therapies. She underwent HLA-matched unrelated allogeneic bone marrow transplantation (UBMT), together with a myeloablative conditioning regimen, after achieving a second CR and has survived without a recurrence for more than 24 months since UBMT. In general, certain secondary chromosomal abnormalities are associated with the phenotype of the disease, which retains its essential biologic characteristics established by the primary abnormality. Accordingly, the primary nature of the leukemic cells in this case differs from the findings for core-binding factor AML with inv(16)(p13q22). We believe this report is the first of de novo AMML Eo with t(5; 17)(q13;q11) showing as a secondary chromosomal aberration with inv(16)(p13q22).