[Show abstract][Hide abstract] ABSTRACT: Copy number variations (CNV) in CEBPA locus represent heterogeneous group of mutations accompanying acute myeloid leukemia (AML). The aim of this study was to characterize different CEBPA mutation categories in regard to biological data like age, cytology, CD7, and molecular markers, and identify possible factors affecting their etiology. We report here the incidence of 12.6% of CEBPA mutants in the population of 262 normal karyotype AML (NK-AML) patients. We confirmed that double mutant AMLs presented uniform biological features when compared to single CEBPA mutations and accompanied mostly younger patients. We hypothesized that pathogenesis of distinct CEBPA mutation categories might be influenced by different factors. The detailed sequence analysis revealed frequent breakpoint-associated microhomologies of 2 to 12 bp. The analysis of distribution of microhomology motifs along CEBPA gene showed that longer stretches of microhomology at the mutational junctions were relatively rare by chance which suggests their functional role in the CEBPA mutagenesis. Additionally, accurate quantification of CEBPA transcript levels showed that double CEBPA mutations correlated with high-level CEBPA expression, whereas single N-terminal CEBPA mutations were associated with low-level CEBPA expression. This might suggest that high-level CEBPA expression and/or accessibility of CEBPA locus contribute to B-ZIP in-frame duplications.
[Show abstract][Hide abstract] ABSTRACT: A monosomal karyotype (MK) was identified by banding techniques (BT) in acute myeloid leukemia (AML). However, BT may be insufficient to determine the actual loss of a complete chromosome, especially in complex karyotypes. We have investigated the effect of monosomy type, total (MK-t) and partial (MK-p), reevaluated by FISH, on prognosis. We have found that complete remission rate and probability of overall survival at 1 year was higher in MK-p (n=27) than MK-t (n=15) group (40% vs. 15.4%, P=0.19 and 30% vs. 9%, P=0.046, respectively). Our results indicate for the first time that monosomy type influences the prognosis of MK-AML.
No preview · Article · Dec 2012 · Leukemia research
[Show abstract][Hide abstract] ABSTRACT: Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal diseases of pluripotent hematopoietic stem or progenitor cells. MDS are characterized by ineffective hematopoiesis, increased apoptosis, peripheral blood cytopenias, and propensity to evolve into acute myelogenous leukemia.
The aim of our investigation was to compare the usefulness of classic cytogenetics and fluorescence in situ hybridization (FISH) to detect chromosome aberrations in myelodysplastic syndromes.
The study was carried out in a group of 58 patients with MDS. G-banding using trypsin and Giemsa (GTG banding) and FISH with a panel of five molecular probes for aberrations with prognostic significance in MDS (cen7/8, 5q31, 7q22/q35, 17p13, 20q13.3) were performed on bone marrow cells.
The use of GTG technique allowed to detect chromosome aberrations in 25 (43.1%) subjects. However, the additional use of FISH showed the presence of aberrations also in additional 10 (17.2%) patients, which shifted 11 patients from one cytogenetic category to another.
The use of FISH with MDS probe panel beside classic cytogenetics improves detection of chromosome aberrations, and also stratification of MDS patients to prognostic groups. Both methods should be used simultaneously in every genetically diagnosed MDS patient.
[Show abstract][Hide abstract] ABSTRACT: The increase of gene copy number is a rare event in blood malignancies (1-10%) in comparison with solid tumors (up to 100% cases). An increase may be of low level, 3-4 gene copies, what the most frequently results from chromosome polysomy. The presence of ≥5 gene copies is called amplification. This may be of low-medium level (5-20 copies) or high level (≥20). Gene amplifications in leukemia involve the most often oncogenes, cell cycle regulating genes, and cytostatics resistance genes. Cytogenetic manifestation of high level amplification are homogeneously staining regions (HSR) or double minute chromosomes (DM). However, in leukemias gene amplifications are situated mainly in structurally aberrant chromosomes, e.g. giant marker chromosomes or rings. MLL or AML1 amplification in acute myeloid leukemia (AML), although it involves different genes, has a similar cytogenetic (complex karyotype, losses of long arms of chromosomes 5 and 7, loss of one copy of TP53), as well as clinical (patients advanced age, frequent therapy with alkylating agents before the onset of AML, resistance to treatment, and poor prognosis) picture.
No preview · Article · Jan 2009 · Acta haematologica Polonica
[Show abstract][Hide abstract] ABSTRACT: We investigated bone marrow cells of 70 acute lymphoblastic leukemia children by conventional cytogenetics (CC), fluorescence in situ hybridization (FISH), and reverse transcription polymerase chain reaction (RT-PCR) methods. CC and RT-PCR for fusion genes BCR/ABL, MLL/AF4, E2A/PBX1, TEL/AML1 were performed at diagnosis in each patient. FISH was performed to verify the presence of fusion genes and MLL rearrangements and to estimate the percentage of abnormal cells. Karyotypes were obtained in 59 (84%) of 70 cases. Thirty-five (59%) of 59 cases revealed chromosome aberrations. Hyperdiploidy>50 chromosomes was present in nine cases, hyperdiploidy 47-50 chromosomes in six, pseudodiploidy in 15, and hypodiploidy in five. BCR/ABL was present in two cases, PBX1/E2A in two, and TEL/AML1 in 14. MLL/AF4 was not found, but the rearrangements of MLL gene were present in five children. The addition of RT-PCR and FISH to CC was of the utmost importance. One of two Ph translocations and one of two t(1;19) were first revealed by RT-PCR. Moreover, FISH showed the percentage of TEL/AML1(+) cells that turned to be an important prognostic factor. The outcome was the best for the children with hyperdiploidy>50 chromosomes without structural changes. It was also good for those with TEL/AML1 present in >or=80% of cells without chromosome aberrations. The presence of pseudodiploidy correlated with poor outcome. The outcome for patients with t(9;22)-BCR/ABL or 11q23-MLL rearrangement was the worst in study group. The presence of BCR/ABL caused eight times increase of risk of death; MLL rearrangements caused 12 times increase.
No preview · Article · Dec 2008 · Annals of Hematology
[Show abstract][Hide abstract] ABSTRACT: Niezrównoważone aberracje chromosomowe stanowią jedną z głównych przyczyn niepełnosprawności intelektualnej i wad wrodzonych. Analizowaliśmy korelacje genotyp-fenotyp u dziewczynki z dysmorfią, wadą serca i napadami hipoglikemii. Probandka urodziła się o czasie, po 2 latach trwania małżeństwa, z urodzeniową masą ciała 2880 g. Po urodzeniu stwierdzono nieprawidłowy fenotyp. Opisywano małogłowie, nieregularną czaszkę, wąskie, krótkie szpary powiekowe, hipoplastyczny nos, hipoplastyczne paznokcie, pojedynczą bruzdę dłoni prawej, klinodaktylię palców V, nadmierne owłosienie pokrywające twarz, ramiona i uda, wadę serca i refluks pęcherzowo-moczowodowy. U pacjentki rozpoznano również niedoczynność tarczycy oraz napady hipoglikemiczne z drgawkami. W badaniu cytogenetycznym potwierdzonym metodą FISH z sondami WCP4 i WCP9, stwierdzono obecność niezrównoważonego kariotypu 46,XX,der(9)t(4;9)(q21;p22),9ph. U matki pacjentki stwierdzono kariotyp prawidłowy żeński z pericentriczną inwersją chromosomu 9. Ojciec dziewczynki nie wyraził zgody na badanie cytogenetyczne.
No preview · Article · Mar 2007 · Pediatria polska
[Show abstract][Hide abstract] ABSTRACT: Introduction. The frequency of congenital malformations in live born infants varies between 0.4 up to 4%. The frequency of the same in stillborns is higher and varies from 9 up to 20%. About 35% of defects of determined etiology are caused by exclusively genetic factors. The aim. The aim of this report was an analysis of genetic causes of reproductive failures in couples with spontaneous abortions and stillbirths or live births with congenital malformations, with consideration of malformation type in fetus and infant and karyotypes of the parents. Material and methods. The karyotype analysis of the parents was performed on metaphasal or prometaphasal chromosomes, obtained from 72-hour cultures of peripheral blood lymphocytes, GTG banded, and in single cases, by with fluorescence in situ hybridization (FISH). Results. Among 59 pairs, the analysis revealed structural aberrations in 7 (11.85%). In one woman with spontaneous abortion, one healthy child and one acranion diagnosed in 18 hbd, a translocation t(3;10)(p25;q21) was identified. The other balanced translocations were present in men: t(4;13)(q34;q31), t(10;22)(p11.2;q13), t(3;14)(p25;q24), t(13;18)(q14;q21.1). In one woman a Robertsonian translocation t(14;21)(q10;q10) was found, an other woman carried an unidentified chromosome 16 aberration. Recognition of causes of reproductive failures make it possible to improve genetic counseling efficacy and prevention of further failures.
No preview · Article · Jan 2007 · Pediatria polska
[Show abstract][Hide abstract] ABSTRACT: The results of clinical and laboratory observations of 119 MDS patients divided acc. to FAB, and - after excluding RAEB-t and CMML groups -- of 95 patients divided accordingly to WHO classification are presented. The diagnosis of MDS was based on medical interview, physical examination, blood biochemistry, peripheral blood (PB) and bone marrow (BM) cytomorphology and cytochemistry, trephine biopsy and cytogenetic examination. All hematologic examinations were done according to routine methods. Cytogenetic analyses were carried out on BM cells from 24-48 h cultures in standard conditions. At least 15-20 GTG-banded metaphases were analyzed in every patient. The survival time (ST) of patients differed significantly between the FAB or WHO groups, with p=0.0004 for FAB and p=0.02 for WHO. The progression to AML was more common in less favorable groups, with p=0.0001 for FAB and p=0.00016 for WHO. The distribution of IPSS prognostic index among the groups showed statistically significant difference (p=0.0004 for FAB, and p=0.0001 for WHO), whereas the distribution of karyotypic abnormalities did not. However, in univariate analysis statistically significant influence on ST showed, beside the both classification systems: cytogenetics, the presence of blasts in PB, age and IPSS index. In multivariate analysis the sole independent prognostic factors were: PB blasts and cytogenetics. The authors conclude that the WHO classification offers a good prognostic tool for MDS patients. However, the karyotype and the presence of blasts in PB should always be taken into account.
[Show abstract][Hide abstract] ABSTRACT: More than 150 cases of 9p trisomy have been reported to date. Here we present a 2 month-old girl, born in good general condition, weighing 2400 g. High levels of toxo-IgM and IgG were found in the mother is blood after delivery. In the girl only toxo-IgG were found. Respiratory problems, pneumonia, polyglobulia and early icterus were also observed after birth. At the age of 5 months the girl was hypotrophic (weight 3300 g, height 56 cm). Characteristic facial dysmorphy, fifth finger clinodactyly and hypoplastic nails were found. Cytogenetic analysis with GTG and CBG banding, and FISH with 9 and 15 whole centromere painting probes disclosed an abnormal karyotype: 46,XX,-15,+der(15) t(9;15)(q10;q10). The karyotypes of parents were normal. The majority of phenotypic features of the child fit the trisomy 9p phenotype, but some of them could also be caused by congenital toxoplasmosis.
No preview · Article · Jan 2006 · Pediatria polska
[Show abstract][Hide abstract] ABSTRACT: About 10-15% of clinically diagnosed pregnancies end by spontaneous abortion. One of the causes of recurrent abortions is the presence of chromosome aberrations in a parent. The paper presents the results of cytogenetic investigations in 107 couples referred to genetic council clinic because of at least 2 spontaneous abortions. Cytogenetic analysis was performed on peripheral blood lymphocytes after standard 72h PHA-stimulated culture. At least 20 GTG- and CBG-banded metaphases were analyzed in each patient. Fluorescence in situ hybridization technique was used as to precisely define cytogenetic results. Chromosome aberrations were found in 7 couples (6.54%), exclusively in women. Numerical aberration (47,XXX) was present in 1 woman, and balanced structural aberrations in 6 (5.61%). In 3 of them balanced translocations were disclosed: t(7; 19)(p13;p13.3), t(8;16)(q24;q22), and t(3;8)(q21;p21), in 2--inversions: inv(2)(p25q31), inv(17)(p12p13.3), and in 1--der(20). Pericentric inversion of chromosome 9 was found in 3 men. The analysis of nongenetic factors showed that neither age, nor congenital anomalies of uterus could be an important factor causing abortions in analyzed couples with aberrations. However, infections and muta- or teratogenic exposure could contribute to loss of pregnancies in some cases. Authors conclude that karyotype analysis should be an integral part of diagnostics in couples with recurrent abortions.
No preview · Article · Feb 2005 · Wiadomości lekarskie (Warsaw, Poland: 1960)
[Show abstract][Hide abstract] ABSTRACT: Background. Early occurrence of the multidrug resistance (MDR) in de novo acute myeloid leukaemia (AML) may contribute to the treatment failure. Objectives. Prospective investigatiom of the clinical significance of the MDR proteins overexpression and their functional augmenting, in the context of other AML prognostic factors, such as age, immunophenotype and cytogenetic profile. Materials and methods. The authors examined expression of MDR proteins (ABC transporters: MDR1, MRP1, MDR3, BCRP) and others (LRP and GSTπ) and performed MDR functional assay in peripheral blood blasts of 25 patients with de novo AML at diagnosis and after the first chemotherapy cycle consisting of a 3 + 7 combination of DNR/Ara-C. Multidrug resistance proteins presence and their functional activity (fluorescent dye efflux) were estimated by flow cytometry. Results. Thirteen out of the 25 AML patients (52%) attained a complete remission (CR) with induction treatment, one had partial remission (PR) and eleven did not achieve remission. Out of eleven AML patients without CR, two died in aplasia and nine were classified as an early death due to disease progression. All AML patients who achieved remission were younger than 55 years. Among eleven AML patients without remission nine expressed CD34; 6 of them had intermediate and 5 unfavourable cytogenetic profile. In 10 out of 25 AML patients (40%) overexpression of MDR was shown at diagnosis, and was irreversible in 9 of them and their clinical outcome was poor (6 did not achieve CR, 1 had PR and one who obtained CR relapsed), whereas one patient who reversed achieved CR. The functional MDR1 assay showed the decreased Rh123 efflux, both at diagnosis and after the first chemotherapy cycle in 12 AML patients (48%) and it influenced patients outcome in a similar manner as MDR1 expression. At diagnosis other MDR proteins were also elevated in some AML patients: GSTπ in 19 (76%), LRP in 9 (36%), MRP in 4 (16%) and MDR3 in 2 (8%). In 7 AML patients (20%), both at diagnosis and after the first chemotherapy cycle the co-expression of MDR1 with MRP, LRP, GSTπ and Rh123 efflux impaired (3 patients), with LRP, GSTπ and Rh123 efflux impaired (1 patient) or with GSTπ and Rh123 efflux impaired (2 patients) resulted in 6/7 AML patients in chemotherapy resistance, and the remaining one who achieved remission was young and had favourable cytogenetic profile. Conclusions. In view of the results obtained, the advanced age, unfavourable cytogenetic profile, overexpression of MDR1 at diagnosis and co-expression of other MDR proteins together with their functional activity contribute to the treatment failure in de novo AML.
No preview · Article · Jan 2005 · Advances in Clinical and Experimental Medicine
[Show abstract][Hide abstract] ABSTRACT: Cytogenetic analyses were performed in 72 acute myeloid leukemia (AML) patients > or = 60 years old. Karyotype was normal in 35 (48.6%) patients (group III). 3 patients (4.2%) had favourable karyotype with t(15;17) as an isolated aberration (group IV). 21 patients (29.2%) had adverse karyotypes (group I) and 13 (18%) had intermediate karyotypes (group II). Adverse karyotypes were simple (< 3 aberrations), with add 3q, 5q-, 7q-, in 5 persons, and complex (> or = 3 aberrations) in 16. Karyotypes of 14 patients from the latter group contained > or = 5 aberrations. Laboratory and clinical data were comparable between groups with > or = 3 and with > or = 5 changes. In more than 2/3 complex karyotypes chromosome 5 and 7 aberrations also were found. AML clinical course of group II patients was more similar to that of group I than of groups III and IV. A frequency of complete remissions differed statistically between group I and the others and a frequency of complete and partial remissions together--between I + II and III + IV groups. Overall survival time differed statistically between all groups. There were significantly more patients with secondary AML in groups I and II than in group III. Analysis according to FAB did not show prognostic significance of this classification. Authors conclude that cytogenetics have a fundamental prognostic importance in AML of the elderly and should be taken into account in establishing therapeutic strategies.
No preview · Article · Jun 2003 · Polskie archiwum medycyny wewnȩtrznej
[Show abstract][Hide abstract] ABSTRACT: Chromosomal changes during therapy with IFN-alpha were analysed in 21 patients suffering of chronic granulocytic leukemia. Complete or major cytogenetic response (CgR) was obtained in 4 patients, minor in 5 minimal in 7, and no response in 5 patients. Patients showing a low Sokal index more often disclosed CgR. In 6 persons additional chromosomal aberrations were present at diagnosis or during the disease course. They disappeared on IFN-alpha therapy. This fact may be in favour of the influence of IFN-alpha not only on disappearance of Ph chromosome, but also of secondary aberrations, some of them indicating the possibility of an acceleration of the disease. No relation of the CgR, as well as Sokal index value to the survival time in presented small cohort could be observed, which may depend on short observation time. CgR did not depend on a type of fusion of BCR/ABL gene. However, survival time was longer in patients with b3a2 fusion.
No preview · Article · Jan 2000 · Polskie archiwum medycyny wewnȩtrznej