The 11q23 breakpoint in acute leukemia with t(11;19)(q23;p13) is distal to those of t(4;11), t(6;11) and t(9;11).

Thirteen cosmid probes were mapped on the long arm of chromosome 11 between 11q22 and 11q24 by nonradioactive in situ hybridization. Starting with these localizations and those of other probes mapped to 11q23, four acute leukemias with translocations involving 11q23 were studied with the same method. The translocation breakpoints of the t(4;11)(q21;q23), t(6;11)(q27;q23), t(9;11)(p21-p22;q23), and t(11;19)(q23;p13) were confirmed to be distal to CD3D. The probe cC111-304 was proximal to the t(11;19) breakpoint while distal to the breakpoints of the other rearrangements. In view of the diversity of chromosomal abnormalities involving band 11q23, our finding extends the molecular heterogeneity of the breakpoint localization in leukemias with rearrangements involving 11q23.     

Concurrent presence of inv(14)(q11q32) and t(4;11)(q21;q23) in Pre-B Acute Lymphoblastic leukemia

The inv(14)(q11q32) is a non-random chromosomal aberration which has been associated with a variety of T-cell malignancies. We have studied a case of inv(14)(q11q32) that is unique in several respects. First, the inversion, which is expressed at the mRNA level, occurred in the context of a pre-B acute lymphoblastic leukemia (ALL) as opposed to a T-cell malignancy. Second, cloning and sequencing of the inversion revealed that it resulted from a fusion between an immunoglobulin heavy chain variable (V) segment and a T-cell receptor delta diversity (D) segment. In addition, the patient had a second chromosomal abnormality at diagnosis, a t(4;11)(q21;q23) which disrupted the MLL gene. The fact that there were two distinct chromosomal abnormalities at diagnosis enabled us to address the question of leukemic clonal evolution during the course of this patient's disease. We present evidence suggesting that the t(4;11)(q21;q23) occurred first, with the inv(14)(q11q32) occurring as a second event.     

Clustering of genomic breakpoints at the MLL locus in therapy‐related acute leukemia with t(4;11)(q21;q23)

Genomic characterization of translocation breakpoints is relevant to identify possible mechanisms underlying their origin. The consistent association of anthracylines (e.g., epirubicin and idarubicin) in inducing therapy‐related acute leukemias (t‐AL) with mixed lineage leukemia (MLL) gene rearrangement suggests that MLL translocations are causative events for t‐AL. Using asymmetric multiplex PCR strategy followed by direct DNA sequencing, we characterized the genomic breakpoints of the MLL and AFF1 genes in two patients who developed t‐AL with t(4;11)(q21;q23). Chemotherapeutic treatment of the primary disease in both patients included topoisomerase II (topo II) targeting agents. In one case, the MLL breakpoint was located in intron 9 at nucleotide position chr11:118354284 while the AFF1 breakpoint was in intron 3 at nucleotide position chr4:87992070. The breakpoint junction sequences revealed an insertion of two nucleotides at the MLL‐AFF1 junction. In the other patient, the MLL breakpoint was located in intron 11 at nucleotide position chr11:118359130‐32 and the AFF1 break was in intron 3 at nucleotide position chr4:87996215‐17. The MLL breakpoint found in the latter patient was identical to that of two previously reported cases, strongly suggesting the presence of a preferential site of DNA cleavage in the presence of topo II inhibitor. In addition, microhomologies at the breakpoint junctions were indicative of DNA repair by the non‐homologous end joining (NHEJ) pathway. This study further supports the evidence that MLL breakpoints in therapy‐related acute leukemia with MLL‐AFF1 are clustered in the telomeric half of the breakpoint cluster region that contains topo II recognition sites. © 2013 Wiley Periodicals, Inc.     

t（11;18）（q11;q23）一家系

先证者　男 ,30岁 ,表型正常。婚后 3年 ,其妻怀孕 5次 ,均在孕 2～ 3个月自然流产 ,妇科检查正常。夫妇非近亲结婚。患者外生殖器正常。精液检查精子数量正常。细胞遗传学检查 :外周血细胞染色体观察 ,常规外周血淋巴细胞培养 ,G显带分析30个细胞 ,先证者核型为 46 ,XY,t(11;18) (11pter→ 11q11∷18q2 3→ 18qter;18pter→ 18q2 3∷ 11q11→ 11qter) ,其妻染色体核型正常。先证者性细胞联会复合体 (synaptonemal complex,SC)观察 ,方法参照文献 [1]。睾丸活检微铺展的 SC电镜观察 ,分析 30个精母细胞 (从早粗线期到晚粗线期 )中 SC图…     

Spontaneous expression of fra(11)(q23) in a patient with Ewing's sarcoma and t(11;22)(q23;q11)

Cytogenetic analysis of a Ewing's sarcoma revealed a 46,XX,t(8;18)(q11;q21.3), t(11;22)(q23–24;q11–12) chromosome pattern. Observation of t(11;22) is consistent with other reported cases of Ewing's sarcoma. One breakpoint in this translocation, 11q23, coincides with the location of a folate-sensitive fragile site. Examination of peripheral blood leukocyte chromosomes from the patient revealed a 46,XX chromosome pattern with spontaneous, fluorodeoxyuridine-, and Bactrim-induced expression of fra(11)(q23). This may be the first demonstration of constitutional fra(11)(q23) expression in a patient with a neoplasm that exhibits a chromosome rearrangement involving this breakpoint and the first observation of spontaneous expression of this fragile site. These results provide a basis for discussion of the relationship between fragile sites and chromosome rearrangements.     

Primary effusion lymphoma of the pericardial cavity carrying t(1;22)(q21;q11) and t(14;17)(q32;q23)

We report a case of primary effusion lymphoma (PEL) in a 75-year-old woman without human immunodeficiency virus or hepatitis C virus, which presented as fever, chest pain, and pericardial effusion. The lymphoma cells were positive for CD20 and CD79a, and were negative for CD3 and CD10. Genomic human herpes virus 8 (HHV-8) and Epstein-Barr virus were not detected in the lymphoma cells. Cytogenetic analysis showed complex abnormalities by the G-banding technique, and spectral karyotyping (SKY) analysis provided more detailed characterization of the chromosomal aberrations, including t(1;22)(q21;q11) and t(14;17)(q32;q23). We did not detect C-MYC gene rearrangement or BCL-2 expression. She was treated successfully with six courses of the CHOP regimen. The present case demonstrated a rare category of PEL that is not associated with HHV-8 or C-MYC gene rearrangement. In addition, SKY analysis disclosed cryptic chromosomal abnormalities involving 1q21 and 17q23.     

Molecular analysis of a t(11;14)(q23;q11) from a patient with null-cell acute lymphoblastic leukemia

/1p;&-3qChromosome 11, band q23, is the frequent site of recurring cytogenetic rearrangements in human leukemia. We have cloned and sequenced the breakpoint junctions from a patient who had null-cell acute lymphoblastic leukemia (ALL) with a t(11;14)(q23;q11). The chromosome 14 breakpoints occurred within the TCRD locus, close to two diversity segments. The chromosome 11 breakpoint occurred between two head-to-head heptamer sequences, and junctional diversity was evident at both derivative junctions, suggesting involvement of the V(D)J recombinase. The TCRA/D locus on the normal chromosome 14 had undergone a Vδ2-Dδ3-ΨJα joining. Two phage clones with this VDJ rearrangement were isolated; one of these contained an intra-Jα region deletion. Two clones with the derivative 11 junction were isolated; one of these had a similar, but not identical, deletion. A heptamer-nonamer recognition sequence (located ～70 kb 5′ to Cα), not associated with a TCR gene coding segment, was found in the immediate vicinity of both 5′ breakpoints. We have designated this sequence 5′^del for 5′ deleting element. An intra-Jα region deletion involving this heptamer-nonamer was previously identified in the leukemia cells recovered from a patient who had T-cell ALL. Fifty kilobases of DNA on 11q23 surrounding the breakpoint were cloned and analyzed. No CpG islands or conserved sequences were identified within this region. Fluorescence in situ hybridization analysis showed that this 11q23 breakpoint mapped distal to the MLL gene associated with the recurring breakpoints in the 4;11, 9;11, and 11;19 translocations, distal to the RCK gene associated with an 11;14 translocation, and proximal to the ETSI gene, which is located at 11q24. © 1993 Wiley-Liss, Inc.     

Derivative (14)t(11;14)(q13;q32)t(11;14)(p11.2;p11.2): a novel unbalanced variant of the t(11;14)(q13;q32) translocation in mantle cell lymphoma

We report the case of a 62-year-old man who presented with splenomegaly, leukocytosis, anemia, and thrombocytopenia. Examination of the peripheral blood, bone marrow, and spleen revealed involvement by mantle cell lymphoma, with some blastoid features and an atypical phenotype. Spleen and bone marrow classical chromosome analysis followed by fluorescence in situ hybridization revealed a novel and unusual unbalanced variant of the t(11;14)(q13;q32) translocation, resulting in a complex derivative chromosome harboring the IGH/CCND1 fusion gene. This chromosome was designated as der(14)t(11;14)(q13;q32)t(11;14)(p11.1;p11.2).     

Unbalanced t(4;11)(q32;q23) in a 34-year-old man with manifestations of distal monosomy 11q and trisomy 4q syndromes

We present a 34-year-old man with an unbalanced translocation between the long arms of chromosome 4 and chromosome 11. He had manifestations of monosomy 11(q23)—minor facial anomalies, abnormal head shape, cryptorchidism; trisomy 4(q32)—hirsutism, renal disease; and manifestations attributable to both imbalances—heart disease, musculoskeletal anomalies, and mental retardation. FISH studies showed that the chromosome 11q23.3 translocation breakpoint was distal to the rare folate sensitive fragile site (FRA11B). The patient is the oldest reported with both imbalance of 4q+ and 11q-. Am. J. Med. Genet. 70:357–360, 1997. © 1997 Wiley-Liss, Inc.     

New complex t(2;11;17)(p21;q23;q11), a variant form of t(2;11), associated with del(5)(q23q32) in myelodysplastic syndrome-derived acute myeloblastic leukemia

The t(2;11)(p21;q23) is a rare recurrent aberration observed in myelodysplastic syndrome (MDS) and acute myeloblastic leukemia (AML). It has been suggested that t(2;11) is specifically associated with a deletion of the long arm of chromosome 5 (5q). A 63-year-old man was initially diagnosed as AML with del(5)(q23q32) as a sole abnormality. At relapse, t(2;11;17)(p21;q23;q11) in association with del(5q) appeared in 14 of 20 cells by G-banding. Spectral karyotyping confirmed three derivative chromosomes, der(11)t(2;11), der(17)t(11;17), and der(2)t(2;17). Fluorescence in situ hybridization analysis with a probe for MLL demonstrated that the breakpoint at 11q23 was telomeric to the MLL gene. Nine of 10 reported cases with t(2;11) and del(5q) had MDS including 5q- syndrome and four of them evolved to AML, as observed in the present case. Our results indicated that t(2;11;17) was a secondary genetic change, which appeared during disease progression after del(5q) was observed. Furthermore, considering another reported case, the MLL gene seems to be not involved in the pathogenesis of MDS/AML with t(2;11) and del(5q).     

t(11;14)(q23;q32) involving IGH and DDX6 in nodal marginal zone lymphoma

Nodal marginal zone lymphoma (NMZL) is a primary nodal B‐cell lymphoma that shares morphological and immunophenotypic characteristics with extranodal and splenic marginal zone lymphoma. Data on altered genes and signaling pathways are scarce in this rare tumor entity. To gain further insights into the genetic background of NMZL, seven cases were investigated by microarray analysis, G‐banding, and FISH. Chromosomal imbalances were observed in 3/7 cases (43%) with gains of chromosome arms 1q, 8q, and 12q being the most frequent findings. Furthermore, we identified a translocation t(11;14)(q23;q32) involving IGH and DDX6. Chromosomal walking, expression analysis, siRNA‐mediated gene knockdown and a yeast two hybrid screen were performed for further characterization of the translocation in vitro. In siRNA experiments, DDX6 appeared not to be involved in NF‐κB activation as frequently observed for genes promoting lymphomagenesis but was found to interfere with the expression of BCL6 and BCL2 in an NF‐κB independent manner. In conclusion, we identified several unbalanced aberrations and a t(11;14) involving IGH and DDX6 providing evidence for a contribution of DDX6 to lymphomagenesis by deregulation of BCL6 in NMZL. © 2012 Wiley Periodicals, Inc.     

Familial t(11;13)(q21;q14) and the duplication 11q, 13q phenotype

Cases of duplication of distal 11q or proximal 13q have been reported independently. A specific translocation resulting in duplication of distal 11q, [der(22)t(11;22)(q23;q11)], has been documented in over 40 cases. We report on a male fetus with chromosomal excess of both distal 11q and proximal 13q resulting from a familial translocation. This case supports the causal association of duplication 11q with neural tube defects. © 1993 Wiley-Liss, Inc.     

Paternal origin of the de novo constitutional t(11;22)(q23;q11)

The constitutional t(11;22)(q23;q11) is a well-known recurrent non-Robertsonian translocation in humans. Although translocations generally occur in a random fashion, the break points of t(11;22)s are concentrated within several hundred base pairs on 11q23 and 22q11. These regions are characterized by palindromic AT-rich repeats (PATRRs), which appear to be responsible for the genomic instability. Translocation-specific PCR detects de novo t(11;22)s in sperm from healthy males at a frequency of 1/10⁴–10⁵, but never in lymphoblasts, fibroblasts or other human somatic cell lines. This suggests that the generation of t(11;22) rearrangement is linked to gametogenesis, although female germ cells have not been tested. Here, we have studied eight cases of de novo t(11;22) to determine the parental origin of the translocation using the polymorphisms on the relevant PATRRs. All of the eight translocations were found to be of paternal origin. This result implicates a possible novel mechanism of sperm-specific generation of palindrome-mediated chromosomal translocations.     

Translocation t(11;14)(q13;q32) in chronic lymphoid disorders.

The translocation t(11;14)(q13;q32) has been described in a spectrum of B-lymphoproliferative diseases and involves a putative oncogene, BCL1, which maps to chromosome band 11q13. Recent evidence indicates that this abnormality may delineate particular subtypes of lymphoma, such as intermediate lymphocytic and centrocytic lymphomas. Thus the possible significance of the t(11;14) within B-cell disorders should be reexamined in the light of a more objective approach to classifying these diseases by morphology, histology, and immunophenotype. We describe 16 patients with t(11;14)(q13;q32) from a series of 90 patients with chronic lymphoid disorders in whom clonal chromosome abnormalities were detected. All the cases were leukemic: prolymphocytic (B-PLL; 4/15 cases), chronic lymphocytic leukemia (CLL) with increase in prolymphocytes (2/9 cases), or non-Hodgkin lymphoma in leukemic phase, intermediate (3/4 cases), lymphoplasmacytic (2/2 cases), splenic lymphoma with villous lymphocytes (4/18 cases), and follicular (1 case). None of the CLL (25) or hairy cell leukemia cases (15) had t(11;14). Our findings showed that t(11;14) occurred in leukemias of mature B cells with lymphoplasmacytic features as judged by morphology and immunophenotype.     

Molecular cytogenetics localizes two new breakpoints on 11q23.3 and 21q11.2 in myelodysplastic syndrome with t(11;21) translocation.

Translocation t(11;21)(q24;q11.2) is a rare but recurrent chromosomal abnormality associated with myelodysplastic syndrome (MDS) that until now has not been characterized at the molecular level. We report here results of a molecular cytogenetic analysis of this translocation in a patient with refractory anemia. Using FISH with a panel of 11q and 21q cosmid/YAC probes, we localized the chromosome 11 breakpoint at q23.3 in a region flanked by CP-921G9 and CP-939H3 YACs, distal to the HRX/MLL locus frequently involved in acute leukemias. The chromosome 21 breakpoint was mapped in a 800-kb fragment inserted into the CP-145E3 YAC at 21q11.2, proximal to the AML1 gene. It is noteworthy that in all four cases with a t(11;21) reported until now, a second der(11)t(11;21) and loss of normal chromosome 11 could be observed either at diagnosis or during the course of the disease. Since in our case heteromorphism was detected by FISH on the centromeric region of the two der(11), the second der(11) chromosome could be the result of a mitotic recombination that had occurred on the long arm of chromosome 11, rather than of duplication of the original der(11). Constancy of secondary karyotypic changes resulting in an extra copy of the putative chimeric gene at der(11), loss of 11 qter sequences, and partial trisomy 21 suggest that neoplastic progression of MDS cases with a t(11;21) may be driven by the same mechanism(s).     

Clinicopathologic analysis of the impact of CD23 expression in plasma cell myeloma with t(11;14)(q13;q32)

A recent study has shown that 10% of plasma cell myelomas (PCMs) express CD23 and that expression is associated with abnormalities of chromosome 11, mainly t(11;14)(q13;q32); however, only 40% of t(11;14)(+) PCMs express CD23. Because these results were generated in a limited patient cohort and because the clinical relevance of CD23 expression in PCMs with t(11;14)(q13;q32) has not been fully characterized, we addressed this question in a large series of patients with t(11;14)(+) PCM. Forty-two bone marrow biopsies from patients with t(11;14)(+) PCM were evaluated for CD23 expression by immunohistochemistry. CD23 expression was correlated with laboratory and clinical data and outcome after autologous stem cell transplantation, including event-free survival and overall survival (OS). Plasma cell myelomas with t(11;14)(q13;q32) were frequently CD20(+) (46.4%) and CD56(−) (53.8%) and had a nonhyperdiploid karyotype (97.6%) with frequent 13q deletion (33.3%). Of 42 cases, 19 (45.2%) expressed CD23. CD23(+) PCMs were more likely to present with platelet counts less than 150 × 10³/μL (100% vs 50%, P = .006). There were no significant differences in other laboratory or presenting clinical data. The median event-free survival in patients treated with autologous stem cell transplantation (n = 29) was similar regardless of CD23 status, whereas the median OS (all patients) was longer in CD23(−) than in CD23(+) PCMs: not reached vs 3365 days (P = .08). Our findings suggest that patients with t(11;14)(+)/CD23(+) PCM present with lower platelet counts and may have a shorter OS than those with t(11;14)(+)/CD23(−) PCM.     

Recombination hotspot associated factors specifically recognize novel target sequences at the site of interchromosomal rearrangements in T-ALL patients with t(8;14)(q24;q11) and t(1;14)(p32;q11)

A DNA binding protein was identified which binds to two noveltarget-like sequences: (I) at the 5' flanking site of the breakpointjunction of chromosome 8 in a patient with T-acute lymphoblastlcleukemla (ALL) carrying the t(8;14)(q24;q11) rearrangement and(II) on chromosome 1 in three of five T-ALL patients with thet(1;14)(p32;q11) rearrangement. This protein [provisionallycalled recombination hotspot associated factor (ReHF-1)] wasalso found to bind to a similar target sequence that is presentImmediately at the 3' end of the human V3 gene segment. In asmall number of lines tested, the ReHF-1 protein was expressedin lineage T cells and in a number of B cell precursor ALLswhose TCR locus has been rearranged. The molecular weight ofReHF-1 protein was determined to be 30 kDa by UV cross-linkinganalysis. Gel filtration chromatography and sedimentation velocitycentrifugation analyses indicate that the ReHF-1 protein existsas a multimeric protein in its native form. These data mightsuggest a possible role for this protein in the rearrangementof the TCR locus. Furthermore, another protein, ReHF-2, thatappears to have strict sequence specificity was found to bindonly to the complementary single strand of the target sequence.The interaction of these proteins with a conserved target sequenceat the chromosomal breakpoint junction might suggest that theyare involved In a novel enzymatic mechanism reminiscent of thegeneral features of DNA recombination or replication eventsIn Escherichia coli or Saccharomyces cenvisiae.     

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.