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Tandem triplication and quadruplication of chromosome 21 in childhood acute lymphoblastic leukemia.

A 5-year-old girl with ALL was shown to have a leukemic clone characterized by a triplication and quadruplication of chromosome 21, arranged in tandem, at diagnosis and relapse, respectively. To our knowledge, this is the second report of this chromosomal anomaly in ALL, which was confirmed by in situ staining. The karyotype evolution in the leukemic clone from triplication to quadruplication at relapse emphasizes the association of chromosome 21 with hematopoietic malignancies.

Aneuploidy↗

[t(3;5) (q21;q31) chromosomal abnormality in a patient with acute myelogenous leukemia with trilineage myelodysplasia].

A 60-year-old woman was admitted in June 1993, because of anemia and purpura and given a diagnosis of acute myelogenous leukemia with trilineage dysplasia. She entered partial remission (PR) after three courses of low-dose Ara-C and G-CSF, but never reached complete remission (CR) in spite of additional chemotherapy. In October 1994, the number of leukocytes, myeloblasts, and erythroblasts in the patient's peripheral blood increased, and her clinical condition deteriorated. The disease was resistant to other therapy. The patient had pneumonia and died of septic shock in December 1994. A chromosomal analysis performed on admission showed 46,XX,t(3;5) (q21;q31) [9/9]. As an additional chromosomal abnormality, deletion of the X chromosome was observed in January, 1994. Analysis of the p53 gene by the polymerase chain reaction-single strand conformation polymorphism method showed one base transposition, from TAT to TGT (Tyr to Cys), at codon 220 of exon 6. Karyotype evolution and p53 gene mutation were observed during the disease course and may have been related to progression of the disease.

Chromosomes, Human, Pair 3↗

Chromosome evolution and improved cytogenetic maps of the Y chromosome in cattle, zebu, river buffalo, sheep and goat.

Comparative FISH-mapping among Y chromosomes of cattle (Bos taurus, 2n = 60, BTA, submetacentric Y chromosome), zebu (Bos indicus, 2n = 60, BIN, acrocentric Y chromosome but with visible small p-arms), river buffalo (Bubalus bubalis, 2n = 50, BBU, acrocentric Y chromosome), sheep (Ovis aries, 2n = 54, OAR, small metacentric Y chromosome) and goat (Capra hircus, 2n = 60, CHI, Y-chromosome as in sheep) was performed to extend the existing cytogenetic maps and improve the understanding of karyotype evolution of these small chromosomes in bovids. C- and R-banding comparison were also performed and both bovine and caprine BAC clones containing the SRY, ZFY, UMN0504, UMN0301, UMN0304 and DYZ10 loci in cattle and DXYS3 and SLC25A6 in goat were hybridized on R-banded chromosomes by FISH. The main results were the following: (a) Y-chromosomes of all species show a typical distal positive C-band which seems to be located at the same region of the typical distal R-band positive; (b) the PAR is located at the telomeres but close to both R-band positive and ZFY in all species; (c) ZFY is located opposite SRYand on different arms of BTA, BIN, OAR/CHI Y chromosomes and distal (but centromeric to ZFY) in BBU-Y; (d) BTA-Y and BIN-Y differ as a result of a centromere transposition or pericentric inversion since they retain the same gene order along their distal chromosome regions and have chromosome arms of different size; (e) BTA-Y and BBU-Y differ in a pericentric inversion with a concomitant loss or gain of heterochromatin; (f) OAR/CHI-Y differs from BBU-Y for a pericentric inversion with a major loss of heterochromatin and from BTA and BIN for a centromere transposition followed by the loss of heterochromatin.

Animals↗

Comparative analysis of the cattle and human genomes: detection of ZOO-FISH and gene mapping-based chromosomal homologies.

Comparative chromosome painting with individual human chromosome-specific libraries (CSLs) on cattle metaphase chromosomes delineated 46 homologous chromosomal segments between the two species. Continuous arrangement of these segments on individual cattle chromosomes demonstrates a nearly complete coverage of the bovine karyotype and shows physical boundaries of bovine chromosomal segments homologous to individual human chromosomes. Alignment of the available comparative gene mapping data with the homologous segments strongly supports the detected gross homologies between the karyotypes of the two species. In addition to cattle, four human CSLs were hybridized to sheep metaphase chromosomes also, to further verify the known karyotype homology within the Bovidae. Besides its application to karyotype evolution research, the comparative knowledge provides for rapid expansion of the much needed Type I locus-based bovine gene map.

Animals↗

[Proliferation of micromegakaryocytes in acute myelocytic leukemia associated with 5 q- as the sole karyotypic abnormality].

The authors report a de novo AML (M2) patient associated with 5q- as the sole karyotypic abnormality. A 76-year-old woman was referred to our hospital because of anemia and leukocytosis. On examination a neck lymph node was enlarged, but neither the liver nor the spleen could be palpated. The hemoglobin level was 7.1g/dl, the mean corpuscular volume 102fl and the white-cell count was 256.1 x 10(3)/microliters with 87% blast cells. The platelet count was 10.9 x 10(4)/microliters. The bone marrow was hypercellular with 79.8% blast cells and showed dysmegakaryocytopoietic features (hypolobulation, multiple separated nuclei and micromegakaryocytes). Blast cells gave a positive reaction for peroxidase and alpha NB esterase which was not blocked by NaF. The diagnosis of AML (M2) was made but she died before chemotherapy. Autopsy revealed general hemorrhagic tendency and leukemic cell infiltration. Chromosome analysis of the bone marrow showed 46,XX,del(5) (q13q31). Electron micrographs revealed increase of micromegakaryocytes as small as myelocytes and aggregation of demarcation membranes in some megakaryocytes. This may suggest that some molecular changes, instead of karyotypic evolution, contributed to a leukemic transition from the 5q- syndrome to AML with 5q- as the sole abnormality.

Aged↗

Chromosome studies of enriched blast cell fractions in myelodysplastic syndromes terminating in acute myeloid leukemia.

For a better understanding of the karyotype evolution of different marrow cell populations in the course of MDS, 6 patients who eventually developed overt leukemia, belonging to a series of 46 MDS referred to our Institution, were studied ad diagnosis and at leukemic progression. In each case the blast cells were separated from the maturing precursors of the erythroid and granulocytic lineage by centrifugation on a Percoll density gradient. Parallel chromosome investigations were performed in each cell fraction. Cytogenetic analysis performed at presentation did not reveal distinctive karyotype features in metaphases arising in the blast enriched cell fraction, as compared with those obtained from the fraction containing erythroblasts and promyelocytes--myelocytes. These findings suggest that in the initial phase of MDS blast cells may lack distinctive cytogenetic features and may thus represent part of a clonal preleukemic proliferation. At the time of leukemia onset, clonal aberrations [trisomy 21 and del(11)(q23)] showing a restricted pattern of distribution within the blast cell enriched fractions were detected in two patients, whereas one patient showed an increase in size of the abnormal clone carrying monosomy 7, an aberration detected in metaphases obtained from both cell fractions. Thus, some evolutive steps in the natural history of these disorders can be heralded by the acquisition of chromosome aberrations more readily detectable in blast enriched cell fractions. In some cases, partial loss of differentiative capability by the abnormal clone may account for the detection, at leukemia onset, of chromosome aberrations involving both the blast cell fraction and the erythroblast-promyelocyte enriched cell fraction.

Blast Crisis↗

Karyotypic changes in the preclinical and subsequent stages of malignant mesothelioma: a case report.

The karyotypic evolution was evaluated in cells from recurring pleural effusions in a patient previously exposed to asbestos. Pleural malignant mesothelioma (MM) was diagnosed 4 years after the first cytogenetic examination. The primary cytogenetic changes consisted of loss of chromosomes 1p,14,21, Y, both 22, and derivative chromosomes involving 1, 2, and 14. The modal chromosome number was 44. Sixty-seven percent of the cells had a normal karyotype. After 4 years of spontaneous remission, only 6% of the cells had a normal karyotype, 42% had the same karyotypic changes as found previously, whereas 52% had additional derivative chromosomes involving chromosomes 1, 3, 5, 7, 8, and 12, trisomy 7, 7p, and 11, and partial or whole monosomy 3, 8, and 9. The chromosomal changes are in agreement with the main findings in previous reports. The karyotype remained quite stable for 7 months in vitro. After 23 months in culture, all the cells were near-triploid. Cells established in culture were cytokeratin positive. All derivative and marker chromosomes identified in the cultured cells had previously been observed in direct preparations from the pleural effusions. We conclude that chromosomes 1, 14, 21, and 22 may be involved in the preclinical stage of development of asbestos-induced mesothelioma, whereas the later chromosomal changes may be related to progression of the tumor.

Aged↗

(TTAGGG)n telomeric sequence in selachian chromosomes.

The distribution of telomeric sequence (TTAGGG)n in the genomes of Chondrichthian species at different stages of evolution was investigated both by DNA genomic hybridization, and by fluorescence in-situ hybridization (FISH) of metaphase chromosomes. The sequence is highly conserved in all the species examined. FISH revealed a label uptake only by the telomeres in Raja asterias. However, in Torpedo ocellata, we revealed pericentromeric and interstitial sequence localization on some chromosome pairs in addition to the hybridization signal on telomeres. These findings confirm that the karyotype evolution of these fish began by Robertsonian fusion.

Animals↗

Heteromorphic sex chromosomes of lizardfish (Synodontidae): focus on the ZZ-ZW1W2 system in Trachinocephalus myops.

The karyotype and DNA content of four lizardfish species (family Synodontidae), that is, Saurida elongata, Synodus ulae, Synodus hoshinonis and Trachinocephalus myops, were analyzed. The karyotype of T. myops significantly differed from that of the other three species having diploid chromosome number of 48 with mainly acrocentric chromosomes and the ZZ-ZW sex chromosome system. The chromosome number of male T. myops was 2n = 26, while that of female T. myops was 2n = 27. The karyotype consisted of 11 pairs of metacentrics, one pair of acrocentrics and, in addition, two large metacentrics in the male and a single large metacentric, a distinctly small subtelocentric and a microchromosome in the female. C-banding demonstrated that in the female the subtelocentric chromosome and the microchromosome were heterochromatic. The karyotype of T. myops was thought to be derived from a 48 chromosome type synodontid fish through the involvement of Robertsonian rearrangement; the rearrangement of the sex chromosomes proceeded during karyotype evolution. Among the chromosomes, the large metacentrics were determined to be neo-Z (a fusion of the original Z and an autosome), the microchromosomes the W1 (originally W), and the subtelocentric chromosomes the W2 (derived from an autosome pair). The miniaturization of W1 and W2 chromosomes and their heterochromatinization suggested that sex chromosomes in this species have been already highly differentiated. The findings on DNA content implied that the karyotype of T. myops evolved by centric fusion events without loss in DNA amount.

Animals↗

[Clinical efficacy and side effects of STI571 in treatment of patients with chronic myeloid leukemia].

BACKGROUND & OBJECTIVE: The aberrant regulation of the protein tyrosine kinase (PTK) activity of P210(BCR-ABL), which is the protein product of Bcr-Abl fusion gene leads to the pathogenesis of chronic myeloid leukemia (CML). Though STI571 can inhibit specifically the PTK activity of P210(Bcr-Abl) and greatly improve the clinic curative effect on CML in chronic phase, its effect on CML in accelerated phase and blast crisis is not clear. In this article, we attempted to analyze the clinic efficacy and side effect of STI571 treatment on CML patients in different phase. In addition, we analyzed the potential mechanism of STI571 resistance in accelerated/blast crisis CML with genetic methods. METHODS: A total of 22 cases of CML, 14 cases male and 8 female, 6 cases in chronic phase and 16 cases in accelerated/blast crisis phase, were treated with STI571. According to the efficacy standard, the hematological and cytogenetic response of 22 cases CML were analyzed, by determining the positive rate of Ph chromosome in bone marrow from the patients treated with STI571 for 3 months. Furthermore, the karyotype evolution of those patients showing STI571 resistance was analyzed. At the same time, the side effects and adverse events of STI571 treatment were evaluated. RESULTS: 6/6(100%) cases of CML patients in chronic phase acquired hematological CR and cytogenetic response. 4/16(25%) cases in accelerated phase or blast crisis acquired hematological CR and 8/16(50%) cases acquired cytogenetic response. 3 CML patients in blast crisis showed secondary STI571 resistance. The karyotype analysis shows 2 with 2 Ph chromosome and other additional abnormality. I/II grade non-hematological toxicity was observed in all the patients, including edema (77.3%), side effects of digestive system (36.4%) and myalgia (22.7%) et al. Severe hematological toxicities includes:(1)III/IV grade neutropenia (9 cases):1/6 cases of CML patients in chronic phase, 8/16 cases in accelerated phase or blast crisis; (2)III/IV grade thrombocytopenia (6 cases): 6/16 cases in accelerated phase or blast crisis. The percentage of III/IV grade neutropenia/thrombocytopenia in chronic phase and accelerated/blast crisis phase was compared and no significant statistical difference was observed. CONCLUSIONS: Hematological and cytogenetic responses of different degrees can be acquired in CML-CP and CML-AP/BC patients treated with STI571 and showing statistic difference. STI571 improves the clinic curative effect greatly on CML in chronic phase. CML patients in blast crisis have secondary STI571 resistance with novel 2 Ph chromosome and other additional abnormality, it furnishes the evidence of the gene changes. The slightness of non-hematological toxicity of STI571 in the treatment of chronic myeloid leukemia suggests this drug is relatively safe. Severe hematological toxicities, such as III/IV neutropenia and thrombocytopenia, are more common in accelerated/blast crisis than in chronic phase.

Adolescent↗

Chromosomal findings and their correlation to prognosis in acute lymphocytic leukemia.

Sixteen of the 17 patients with acute lymphocytic leukemia (ALL) were revealed to have chromosome abnormalities in their leukemic cells. Of nine children, six had modal chromosome numbers between 50 and 59; these patients and one additional patient with a pseudodiploid karyotype have achieved and retained a complete remission. The only patient without chromosome abnormalities achieved a remission, but had a relapse and died. The only child who expired without achieving a remission had 47 chromosomes in his leukemic cells. Of eight adults, none had the hyperdiploidy seen in the children. The four with hypo-or pseudodiploidy failed to achieve a complete remission. One patient had 47 chromosomes in his leukemic cells, and this patient and the remaining three, all with ploidy abnormalities, achieved a complete remission, but a relapse occurred and they died. The chromosomal abnormalities were very extensive in most cases, many patients having marker chromosomes of an unknown origin. Four patients clearly exhibited karyotypic evolution when they relapsed. The patients with hyperdiploidy had a better prognosis, and those with pseudodiploidy had a poorer prognosis. The role of individual chromosome aberrations, however, remains to be elucidated.

Adolescent↗

Partial 6q deletion in a human salivary gland adenocarcinoma.

G-banding analysis was performed on a cultured human salivary gland adenocarcinoma. Clonal chromosome abnormalities consisted of a 6q- marker and loss of the Y chromosome. The 6q- marker had resulted from a long arm interstitial deletion, del(6)(q22q24). The present results, together with our previous findings of 6q deletions in other types of salivary gland tumors, indicate that deletions of 6q are characteristic for the karyotypic evolution of all major types of malignant salivary gland tumors. A common pathogenetic mechanism for these tumors might well be loss of a tumor suppressor gene located on 6q.

Adenocarcinoma↗

Correspondence of human chromosomes 9, 12, 15, 16, 19 and 20 with donkey chromosomes refines homology between horse and donkey karyotypes.

Whole chromosome paints for human (HSA) chromosomes 9, 12, 15 and 20 and arm-specific paints for HSA16p, 19p and 19q were applied on donkey metaphase spreads. All probes, except HSA19p, gave distinct hybridization signals on donkey chromosomes/chromosomal segments. The results show direct segmental homology between human and donkey genomes, and enable refinement of correspondence between donkey and horse karyotypes. Of specific interest is the identification of hitherto unknown correspondence between four equine acrocentric chromosomes (ECA22, 23, 25 and 28) and the donkey chromosomes. Overall, the findings mark the beginning of an ordered study of comparative organization of genomes/karyotypes of the equids, that can shed light on karyotype evolution and ancestral chromosomal condition in the Perissodactyls.

Animals↗

Fluorescence in situ hybridisation studies to characterise complete and partial monosomy 7 in myeloid disorders.

Eight patients with myeloid disorders characterised by a karyotype including apparent monosomy or partial monosomy 7, in the presence of a ring or marker chromosome, were investigated by fluorescence in situ hybridisation (FISH) with a chromosome 7 centromere-specific probe and an Alu-PCR derived chromosome 7 paint. In 4 of 5 cases a ring chromosome was shown to be of chromosome 7 origin; in one of these the apparent ring was shown to consist solely of chromosome 7 centromeric material, and in the fifth case the ring was derived from chromosome 18. In three cases monosomy 7 had arisen during the course of karyotype evolution and was clearly not the primary cytogenetic abnormality. One further case demonstrated fragmentation and cryptic translocation of chromosome 7 material. In the last case a chromosome described as der(l)t(1;7)(p11;p11) was redefined as dic(1;7)(p11;q11). The application of FISH has enabled a more accurate characterisation of chromosome abnormalities, and extended studies of this type may eventually lead to more precise prognostic groups defined by karyotype.

Adult↗

Chromosome changes in human monocytic cell lines with in vitro spontaneous malignant transformation.

Serial chromosome studies were performed on four monocytic cell lines established from bone marrow samples of patients suffering from hematopoietic disorders other than leukemia. A spontaneous in vitro transformation towards a malignant phenotype has been found to be related to the karyotype evolution. The correlation between the chromosome changes of these cell lines and those described in human cancer and leukemia is discussed.

Adolescent↗

Karyotypic abnormalities in transformed chronic granylocytic leukaemia.

Chromosomal abnormalities in three cases of chronic granylocytic leukaemia are presented. The relative importance of 'specific' chromosomal abnormalities, additional to the Ph1 in the karyotypic evolution of chronic granylocytic leukaemia is discussed. A new abnormal metacentric chromosome is described.

Adult↗

Karyologic studies on hybrids between Asian, Ceylonese, and Oceanian type black rats, with a note on an XO female occuring in the F2 generation.

F1 hybrids between the Asian type (2n=42) and Ceylonese type black rats (2n=40) invariably showed 41 chromosomes, while those between the Oceanian type (2n=38) and the Ceylonese type usually showed 39 chromosomes. Twelve F2 hybrids (three litters) were obtained only from the latter combination. Among them, the karyotypes of nine rats were successfully analyzed. They were segregated into the Oceanian type (three rats) and the F1 type (six rats). No Ceylonese type was obtained. From the results of fertility testing in F1 hybrids between these three variants, the Oceanian type is assumed to be more closely related to the Ceylonese type than the Asian type. This coincided well with the results of karyotypic evolution of these geographic variants. Among the nine F2 hybrids examined, one female consistently showed 37 chromosomes with one X chromosome. This XO female appeared to be a normal female and to have been a sporadic natural occurrence.

Animals↗

FISH analysis of the telomere sequences of bulldog ants (Myrmecia: formicidae).

Chromosomes from several species of ants from the genus Myrmecia were hybridized with deoxyoligomer probes of either (T2AG2)7, the putative insect telomere repeat sequence, or (T2AG3)7, the vertebrate telomere repeat sequence. While both sequences hybridized over a range of stringency conditions, (T2AG2)n was clearly the predominant sequence at the termini of the Myrmecia chromosomes. No interstitial sites of either sequence were detected. The genus Myrmecia has a wide range of karyotypes, with chromosome numbers ranging from 2n=2-84. It has been hypothesized that the ancestral karyotype was 2n=4 and karyotype evolution proceeded with an increase in chromosome number. In the absence of detectable interstitial sites of telomere sequence, it is interesting to speculate on the origin of the new telomeres as the chromosome numbers increased.

Animals↗