[Show abstract][Hide abstract] ABSTRACT: Translocations leading to fusions between the immunoglobulin heavy chain gene (IGH) and various partner genes have been reported in B-cell precursor acute lymphoblastic leukemia (B-ALL). However, submicroscopic deletions within IGH in B-ALL have not been rigorously assessed. In this study, we investigated characteristics of IGH submicroscopic deletions, by FISH, in B-ALL with IGH rearrangements. FISH was performed by using commercially available IGH dual-color break-apart rearrangement probes (Abbott/Vysis, Downers Grove, IL, USA; Kreatech, Amsterdam, Netherlands). The study group included seven B-ALL patients with IGH rearrangements, observed by FISH. Among them, two exhibited deletion of the 5' variable region of IGH by FISH. The B-ALL in these two patients included two kinds of abnormal cells; one had an IGH rearrangement without any IGH submicroscopic deletion, while the other had an IGH submicroscopic deletion, which showed that one normal fusion signal and one 3' IGH signal were detected. Thus, submicroscopic deletion of the IGH 5' variable region may have occurred in either the native or rearranged chromosome 14. These findings indicate that B-ALL with IGH rearrangements may be accompanied by submicroscopic deletions of the IGH 5' variable region, which can be detected by FISH. The clinical significance of such deletions is unclear, but the loss of part of the IGH gene in B-ALL warrants further study.
Annals of Laboratory Medicine 01/2015; 35(1):128-31. DOI:10.3343/alm.2015.35.1.128 · 1.48 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: IntroductionMyeloproliferative neoplasms (MPN) and myelodysplastic/myeloproliferative neoplasms (MDS/MPN) may transform into secondary myelofibrosis (MF) or evolve into acute myeloid leukemia (AML). The genetic mechanisms underlying disease progression in MPN and MDS/MPN patients remain unclear. The purpose of this study was to investigate sequential genomic aberrations identified by single nucleotide polymorphism array (SNP-A)-based karyotyping that can detect cryptic aberrations or copy neutral loss of heterozygosity (CN-LOH) in the chronic phase and during disease progression of MPN and MDS/MPN patients.Methods
The study group included 13 MPN and four MDS/MPN patients (seven polycythemia vera (PV); four essential thrombocythemia (ET); two MPN-unclassifiable (MPN-U); one chronic myelomonocytic leukemia (CMML); one atypical chronic myeloid leukemia, BCR-ABL1 negative (aCML); and two MDS/MPN-unclassifiable (MDS/MPN-U)). Among them, five patients (two PV, two MPN-U, and one MDS/MPN-U) progressed to MF and three patients (one CMML, one aCML, and one MDS/MPN-U) transformed to AML. The median follow-up period was 70 months (range, 7-152). Whole-genome SNP-A (SNP 6.0; Affymetrix, Santa Clara, CA, USA)-based karyotyping and JAK2 mutation analysis were performed according to the manufacturer's instructions.ResultsSNP-A showed 19 kinds of genomic aberrations, including seven gains, eight deletions, and four CN-LOH. CN-LOH of 9p involving JAK2 was the most common aberration, followed by 5q deletion and 9p gain. The incidence of genomic changes identified by SNP was not different in patients with disease progression (75%), compared with those without disease progression (56%) (P = 0.4). However, when excluding 9p CN-LOH, the incidence of genomic changes was significantly higher in patients with disease progression than in patients without disease progression (63% and 0%, respectively, P = 0.01). Among eight patients with disease progression, two patients (two MPN-U) showed abnormal SNP-A results, whereas metaphase cytogenetics (MC) analysis showed normal results at diagnosis and during follow-up. In nine patients without disease progression, SNP-A did not show any genomic aberrations except for 9p CN-LOH. In three patients (one PV, one aCML, and one MDS/MPN-U), clonal evolutions were identified by both MC and SNP-A according to disease progression. One PV patient who progressed to MF at 45 months after diagnosis showed sequential genomic changes from 9p CN-LOH to 9p gain by SNP-A. Results of JAK2 mutation analysis were variable depending on the patient. Most of the patients with 9p CN-LOH or 9p gain showed more than 50% of the JAK2 mutant alleles. In one patient (MDS/MPN-U) evolving to AML, the number of JAK2 mutant alleles decreased according to disease progression.Conclusion
This study suggests sequential genomic changes identified by SNP-A may be associated with disease progression.
International journal of laboratory hematology 05/2014; 37(2). DOI:10.1111/ijlh.12257 · 1.87 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The clinical heterogeneity of patients with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) with trisomy 8 as the sole abnormality may result from cytogenetically undetectable genetic changes. The purpose of this study was to identify hidden genomic aberrations not detected by metaphase cytogenetics (MC) using high-resolution single nucleotide polymorphism array (SNP-A)-based karyotyping in AML/MDS patients with a sole trisomy 8. The study group included 8 patients (3 AML and 5 MDS) and array-based karyotyping was done using whole-genome SNP-A (SNP 6.0 and SNP 2.7M). By SNP-A, additional genomic aberrations not detected by MC were identified in 2 patients: 1 AML patient exhibited a copy-neutral loss of heterozygosity (CN-LOH) of 3q21.1-q29 and 11q13.1-q25 and the other patient with MDS (refractory cytopenia with unilineage dysplasia) had CN-LOH of 2p25.3-p15. In particular, the latter patient progressed to AML 18 months after the diagnosis. In 3 patients, aberrations in addition to trisomy 8 were not identified by SNP-A. In the remaining 3 patients, SNP-A could not detect trisomy 8, while trisomy 8 was found in 25-67% of metaphase cells by MC. This study suggests that additional genomic aberrations may in fact be present even in cases of trisomy 8 as sole abnormality by MC, and SNP-A could be a useful karyotyping tool to identify hidden aberrations such as CN-LOH.
[Show abstract][Hide abstract] ABSTRACT: Prognosis is known to be better in cases with isolated chromosomal abnormalities than in those with complex karyotypes. Accordingly, del(20q) as an isolated abnormality must be distinguished from cases in which it is associated with other chromosomal rearrangements for a better stratification of prognosis. We report a case of an isolated del(20q) abnormality with additional genomic aberrations identified using whole-genome single nucleotide polymorphism array (SNP-A)-based karyotyping. A 39-yr-old man was diagnosed with AML without maturation. Metaphase cytogenetic analysis (MC) revealed del(20)(q11.2) as the isolated abnormality in 100% of metaphase cells analyzed, and FISH analysis using D20S108 confirmed the 20q deletion in 99% of interphase cells. Using FISH, other rearrangements such as BCR/ABL1, RUNX1/RUNX1T1, PML/RARA, CBFB/MYH11, and MLL were found to be negative. SNP-A identified an additional copy neutral loss of heterozygosity (CN-LOH) in the 11q13.1-q25 region. Furthermore, SNP-A allowed for a more precise definition of the breakpoints of the 20q deletion (20q11.22-q13.31). Unexpectedly, the terminal regions showed gain on chromosome 20q. The patient did not achieve complete remission; 8 months later, he died from complications of leukemic cell infiltrations into the central nervous system. This study suggests that a presumably isolated chromosomal abnormality by MC may have additional genomic aberrations, including CN-LOH, which could be associated with a poor prognosis. SNP-A-based karyotyping may be helpful for distinguishing true isolated cases from cases in combination with additional genomic aberrations not detected by MC.
Annals of Laboratory Medicine 11/2012; 32(6):445-9. DOI:10.3343/alm.2012.32.6.445 · 1.48 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: A firm understanding of the biology of hematopoietic stem and progenitor cell (HSC/HPC) trafficking is critical to improve transplant efficiency and immune reconstitution during hematopoietic stem cell transplantation (HSCT). Our earlier findings suggested that suppression of CD26 (dipeptidyl peptidase IV) proteolytic activity in the donor cell population can be utilized as a method for increasing transplant efficiency. However, factors in the recipient should not be overlooked, given the potential for the bone marrow (BM) microenvironment to regulate HSCT. STUDY DESIGN AND METHODS: We first evaluated CD26 expression and then investigated the effects of the CD26 inhibitor diprotin A and the absence of CD26 (CD26-/-) in recipient mice on HSC/HPC homing and engraftment using an in vivo congenic mouse model of HSCT. RESULTS: A significant increase in donor cell engraftment into the peripheral blood (PB), and to a lesser extent homing into the BM, was observed in CD26-/- mice or CD26 inhibitor-treated mice. Increased PB engraftment of CD26-/- mice was significant at 3 and 6 months, but not 1 month, after transplant. It was noted that the increased homing was statistically greater with donor cell manipulation (CD26-/- donor cells) than with recipient manipulation (CD26-/- recipient mice). Conversely, donor and recipient manipulation both worked well to increase PB engraftment at 6 months. CONCLUSION: These results provide preclinical evidence of CD26, in the HSCT recipient, as a major regulator of HSC/HPC engraftment with minor effects on HSC/HPC homing and suggest the potential use of CD26 inhibitors in HSCT patients to improve transplant efficiency.
[Show abstract][Hide abstract] ABSTRACT: Chromosomes forming a corresponding ring cannot be clearly defined by conventional cytogenetics or FISH. Karyotypic analyses using whole-genome single nucleotide polymorphism arrays (SNP-A) may result in the identification of previously cryptic lesions and allow for more precise definition of breakpoints. We describe a case of AML with metaphase cells bearing -5, del(11)(q22), and +r. With SNP-A, a 5p-terminal deletion (11 megabases [Mb]), a 5q-terminal deletion (27 Mb), an 11q-interstitial deletion (29 Mb), and a 21q gain (3 Mb) were identified. Therefore, the G-banded karyotype was revised as 46, XY, r(5)(p15. 2q33.2), del(11)(q14.1q23.2), dup(21)(q22.13q22.2)/46,XY. SNP-A could be a powerful tool for characterizing ring chromosomes in which the involved chromosomes or bands cannot be precisely identified by conventional cytogenetics or FISH.
Annals of Laboratory Medicine 07/2012; 32(4):307-11. DOI:10.3343/alm.2012.32.4.307 · 1.48 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Trisomy 22 is closely associated with inv(16) or t(16;16) and could be a marker of cryptic rearrangement of CBFB/MYH11 in acute myeloid leukemia (AML). Trisomy 22 not associated with CBFB/MYH11 rearrangement is a rare event. Here, we report a case diagnosed as refractory anemia with excess blasts-2 (RAEB-2) with sole trisomy 22 in the absence of CBFB/MYH11 rearrangement. The cytogenetic study of bone marrow cells disclosed trisomy 22 in 10% of metaphase cells analyzed. The other chromosomal abnormalities were not found. Fluorescence in situ hybridization (FISH) using CBFB/MYH11 probe to detect cryptic inv(16)(p13q22) showed negative result. We also excluded rearrangements of chromosome 5, 7, 8, 20, and ETV6 by FISH. Sole trisomy 22 not associated with inv(16) is a true entity.
[Show abstract][Hide abstract] ABSTRACT: Single nucleotide polymorphism array (SNP-A)-based karyotyping can identify copy-neutral loss of heterozygosity (CN-LOH) as well as cryptic lesions not detected by metaphase cytogenetics. We report serial genetic studies on a patient diagnosed with chronic myelomonocytic leukemia who progressed to acute leukemia. Monosomy 7 was predominantly found at diagnosis, but clones changed to CN-LOH of chromosome 7 with disease progression. Furthermore, subclones with genomic aberrations of 3q gain, 1p CN-LOH, and trisomy 12 newly appeared, suggesting that they were also involved in the transformation process. Additionally, by SNP-A, a presumably balanced translocation, t(14;20), identified by metaphase cytogenetics, was shown to result in an unbalanced 20q deletion at the breakpoint. The sequential changes identified by SNP-A may provide a better understanding of the mechanism of clonal evolution.
Cancer Genetics 12/2011; 204(12):682-6. DOI:10.1016/j.cancergen.2011.11.003 · 2.42 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Incorporation of novel agents has resulted in an improved response rate and reduced side effects in multiple myeloma. This has prompted combining novel agents in induction chemotherapy in patients with newly diagnosed multiple myeloma. Our patients received 2 cycles of vincristine, adriamycin, dexamethasone (VAD) and then 2 cycles of bortezomib, thalidomide, dexamethasone (VTD) chemotherapy as an induction treatment. Subsequently, autologous stem cell transplantation was performed, and bortezomib was administered as a consolidation therapy. Seventy-one patients were enrolled, and 65 were evaluable for response. After 2 cycles of VAD, the overall response rate was 69%. After VTD, the response rate improved to 97% with a complete response (CR) and near CR rate of 27%. Importantly, patients with cytogenetics, having poor prognostic features, all responded after VTD. Autologous stem cells were successfully collected in all 58 patients with a median CD34+ cell count of 7.12 × 10(6)/kg (range, 1.94-44.7 × 10(6)/kg), except in 1 patient (2%). After ASCT, 36 patients completed bortezomib maintenance with a combined CR and near CR rate approaching 75%. Median time to response was rapid (1.6 months). With a median follow-up duration of 52.7 months, the median TTP was 29.4 months and median OS was not reached. Toxicities proved manageable. In conclusion, sequential VAD and VTD induction therapy in patients with newly diagnosed multiple myeloma was active with manageable toxicity and excellent stem cell yields. The incorporation of bortezomib as a consolidation therapy improved the clinical outcome with the expense of rather frequent development of peripheral neuropathy.
Annals of Hematology 07/2011; 91(2):249-56. DOI:10.1007/s00277-011-1298-9 · 2.40 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Interphase fluorescence in situ hybridization (FISH) can identify submicroscopic deletions adjacent to the breakpoints of rearrangements undetected by conventional cytogenetics. In this study, the characteristics and frequency of the IgH deletion identified by interphase FISH were investigated in patients with multiple myeloma (MM) and chronic lymphocytic leukemia (CLL).
The study group included 29 patients with MM and eight patients with CLL. Interphase FISH was performed with the IgH dual color, break-apart rearrangement probe and the IgH/CCND1 dual color, dual fusion translocation probe.
The IgH deletion was found in 14% (4/29) of patients with MM and 13% (1/8) of the patients with CLL. Four patients had deletions of the whole or variable region of IgH on the native chromosome 14, whereas one patient had a deletion of the IgH variable region on a der(11)t(11;14). In two patients, the IgH break-apart FISH showed both patterns with and without IgH deletions. In cases showing the same pattern by IgH break-apart FISH, the IgH/CCND1 FISH showed different patterns, and vice versa.
A variety of patterns of the IgH deletion were identified by interphase FISH using IgH break-apart and IgH/CCND1 probes in patients with MM and CLL. The results of this study suggest that the integrated information obtained with IgH break-apart and IgH/CCND1 FISH was needed to interpret FISH results unambiguously.
International journal of laboratory hematology 06/2011; 33(3):299-304. DOI:10.1111/j.1751-553X.2010.01290.x · 1.87 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A variant Philadelphia chromosome (Ph) is generated from translocation of one or more partner chromosomes in addition to chromosomes 9 and 22. We have described the cases of 2 patients bearing variant Ph detected by interphase FISH but not detected by G-banded karyotyping and metaphase FISH. FISH was performed using BCR/ABL dual color dual fusion translocation probes (Abbott Molecular, USA). A 52-year-old man was diagnosed with acute leukemia of mixed phenotype. G-banded karyotyping showed 46,XY,t(9;22)(q34;q11.2)/47,idem,+der(22)t(9;22)/46,XY. Interphase FISH revealed nuc ish(ABL1,BCR) × 3(ABL1 con BCR × 2)[329/450]/(ABL1,BCR) × 4(ABL1 con BCR × 3)[5/450]/(AL1,BCR) × 3(ABL1 con BCR × 1)[44/450]. Metaphase FISH showed ish (9;22)(ABL1+,BCR1+;BCR+,ABL+)/der(22)(BCR+,ABL1+). The other case was that of a 31-yr-old male patient diagnosed with CML in the blastic phase. G-banded karyotyping of all 20 metaphase cells showed 47,XYYc,dup(1)(q21q32),del(7)(p11.2),t(9;22)(q34;q11.2). Interphase FISH revealed nuc ish(ABL1,BCR) × 3(ABL1 con BCR × 2)[254/600]/(ABL1,BCR) × 3(ABL1 con BCR × 1)[191/600]. Metaphase FISH showed ish t(9;22)(ABL1+,BCR+;BCR+,ABL1+). These results suggest that typical t(9;22) and variant Ph may coexist in the same patient, and interphase FISH may facilitate the detection of the variant Ph that cannot be detected by G-banded karyotyping alone.
The Korean Journal of Laboratory Medicine 12/2010; 30(6):711-7. DOI:10.3343/kjlm.2010.30.6.711 · 1.31 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Fluorescence in situ hybridization (FISH) analysis can provide important information in the management of patients with hematologic malignancies. However, FISH performed in addition to G-banded karyotype can be labor-intensive and expensive. The aim of this study was to evaluate whether FISH gives additional information in the setting of adequate conventional cytogenetics in cases of hematologic malignancies.
Bone marrow aspirates were obtained from 135 patients at diagnosis (56 AML, 32 MDS, 20 ALL, and 27 MM) between 2005 and 2010. Interphase FISH was performed using the following probes: BCR/ABL1, AML1/ETO, PML/RARA, CBFB, MLL, EGR1, CEP8, and D7S486 for AML; CEP8, D20S108, EGR1, and D7S486 for MDS; BCR/ABL1, MLL, CDKN2A (p16), ETV6, and 6q21/c-myc for ALL; IgH, TP53, D13S25, IgH/CCND1, IgH/MAF, IgH/FGFR3, and 1q21/8p21 for MM. We compared the results of FISH with the corresponding aberrations identified by G-banded karyotype.
Additional genetic aberrations detected by FISH (which were not identified by G-banded karyotype) were 4%, 9%, 50%, and 67% in AML, MDS, ALL, and MM, respectively. In ALL, CDKN2A and ETV6 FISH revealed additional genetic aberrations in 33% and 28% of cases, respectively. In MM, FISH was of benefit in detecting IgH, D13S25, TP53, and 1q21 rearrangements, not detected by G-banded karyotype (31%, 36%, 20%, and 40%, respectively).
These results suggest that performing FISH in addition to G-banded karyotype may contribute little additional genetic information in AML and MDS, whereas routine FISH analysis appears to be an efficient screening method in ALL and MM.
The Korean journal of hematology 09/2010; 45(3):171-6. DOI:10.5045/kjh.2010.45.3.171
[Show abstract][Hide abstract] ABSTRACT: In patients with isolated thrombocytopenia, but without significant dysplasia, diagnosis of idiopathic thrombocytopenic purpura (ITP) rather than myelodysplastic syndrome (MDS) may be taken into account. It is important to make an accurate diagnosis because different treatments are used for ITP and MDS. The purpose of this study was to investigate the clinical and hematologic features of patients who were initially diagnosed as ITP but had cytogenetic abnormalities.
We retrospectively reviewed cytogenetic studies of 100 patients who were diagnosed as ITP from 2004 to 2009 at Mokdong Hospital of Ewha Womans University based on clinical features and hematologic studies. Bone marrow pathology was re-evaluated based on 2008 WHO classification. Cytogenetic analysis was performed by 24-48 hr culture of bone marrow aspirates without using mitogens and 20 metaphases were analyzed.
Of the 100 patients diagnosed as ITP initially, three patients (3%) had cytogenetic abnormalities. They had no thrombocytopenia-related symptoms and thrombocytopenia was found accidentally. The numbers of megakaryocytes in bone marrow were increased and dysplasia was not found in megakaryocyte, erythroid, and myeloid cell lineages. The proportion of blasts was within normal limits. Clonal chromosomal abnormalities found were der(1;7)(q10;p10), add(9)(q12), or t(7;11)(p22;q12). Presumptive diagnosis of MDS or diagnosis of idiopathic cytopenia of undetermined significance (ICUS) was made according to 2008 WHO classification. During the follow up, disease progression was not found.
In patients with suspected ITP, cytogenetic analysis should be done. If specific clonal chromosomal abnormality is found, presumptive diagnosis of MDS has to be considered and close follow up is needed.
The Korean Journal of Laboratory Medicine 04/2010; 30(2):105-10. DOI:10.3343/kjlm.2010.30.2.105 · 1.31 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A 60-year-old man presented with cough, sputum, and dyspnea. He had a history of acute myeloid leukemia and hematopoietic stem cell transplantation with chronic renal failure. Chest CT scans showed miliary nodules and patchy consolidations. Histological examination revealed numerous fibrin balls within the alveoli and thickening of the alveolar septum, both of which are typical pathological features of acute fibrinous and organizing pneumonia (AFOP). We report the first case of AFOP following allogeneic hematopoietic stem cell transplantation.
The Korean Journal of Internal Medicine 07/2009; 24(2):156-9. DOI:10.3904/kjim.2009.24.2.156