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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Fluorescence hybridization in situ with a probe specific for the alphoid sequence of the centromeric region of chromosome 12 was used to evaluate seven cases of B-cell chronic lymphocytic leukemia (B-CLL). Trisomy 12 was detected in interphase cells from one case which did not produce analyzable metaphases. Four out of the seven cases studied showed clear evidence of trisomy 12 in interphase nuclei. In situ hybridization provides an important supplement to classic cytogenetic studies of B-CLL and may help refine our understanding of the clinical correlations of chromosome abnormalities.
Leukemia 1992 Jun
PMID:Interphase detection of trisomy 12 in B-cell chronic lymphocytic leukemia by fluorescence hybridization in situ. 160 99

Tumour cell karyotypes from patients with Burkitt lymphoma (BL) or Burkitt's type leukemia (ALL3) were studied for correlation with survival, bone marrow and cerebral spinal fluid involvement (CSF), human immunodeficiency virus (HIV) serology, and for recurrent cytogenetic abnormalities. The records of 22 patients with BL from our institution and of 148 cases of BL and ALL3 reported in the literature with karyotypes were evaluated for clinical and cytological features. Overall survival was only 28 per cent and 88 per cent of deaths occurred within the first nine months after diagnosis. Those who survived at least 18 months were unlikely to relapse. Age and gender did not significantly affect survival. Patients presenting with advanced Ann Arbor stage, bone marrow or CSF involvement had lower survival rates. The association of translocations involving chromosome band 8q24 with this disease is confirmed. Sixty-two per cent of karyotypes had t(8;14)(q24;q32) translocations; the recognized variant translocations t(8;22)(q24;q11) and t(2;8)(p12;q24) affected 12 per cent and 9 per cent respectively. Seventeen per cent had abnormal karyotypes but no classic translocation. Patients with variant translocations had the poorest survival rates, and those with the classic t(8;14)(q24;q32) did the best. Despite a small sample size, the variant translocation t(8;22)(q24;q11) appeared to occur at an increased frequency in the patients with AIDS. In the entire group, recurrent involvement of chromosome regions 1q2, 6q11-14 and 17p1 suggests that alteration of genes at these loci, B Cell Growth Factor (BCGF) at 1q2 and p53 on 17p, may contribute to the development and progression of this tumour. Similarly, the frequent trisomies of chromosomes 7, 8, 12 and 18 may indicate an effect on tumour cell growth due to increased gene dosage. Trisomy 12 was found in eight tumours, five from patients with AIDS, suggesting that chromosome 12 has a site or gene whose allelic dosage is selected for in AIDS related lymphoma cells. Cytogenetic studies of adult Burkitt lymphoma and leukemia suggest several likely loci for gene alterations that in conjunction with myc translocations can lead to tumorigenesis.
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PMID:Chromosomal abnormalities in adult non-endemic Burkitt's lymphoma and leukemia: 22 new reports and a review of 148 cases from the literature. 186 43

Trisomy 12 is the most common chromosomal aberration in chronic B lymphocytic leukemia (B-CLL). In this study we have investigated trisomy 12 and posed two major questions: (a) What is the origin of the third copy of chromosome 12? and (b) What is the proportion of trisomy 12 cells in malignant clones with this aberration? The origin of an extra copy of chromosome 12 in lymphocytes from patients with B-CLL was studied by the use of probes detecting restriction fragment length polymorphisms on this chromosome. In all six patients that were evaluable, the third copy was derived from a simple duplication of one of the original chromosomes. In none of these patients nor in four patients with two copies of chromosome 12 were losses of the homologue observed. When studying metaphase cells from some CLL patients with trisomy 12, a large proportion of the cells are found to have a normal karyotype. In this study the fraction of normal metaphases was not matched by a similar fraction of cells lacking trisomy 12, as judged by scanning densitometry of hybridization bands. Thus, normal metaphases appear to be derived from a small fraction of easily stimulated probably nonmalignant cells and not from a large second population of malignant cells with a normal karyotype.
Leukemia 1989 Dec
PMID:Molecular analyses of chromosome 12 in chronic lymphocytic leukemia. 258 80

Cytogenetic analysis was successfully performed on 31 of 40 patients with chronic B cell leukemia. Clonal abnormalities were seen in 16 patients using various culture methods. Fourteen of these had unstimulated cultures established of which 13 had the clonal abnormality. Trisomy 12 was observed in seven patients while a 14q32 translocation was present in four. Race, age, hemoglobin, WBC, percentage of lymphocytes and prolymphocytes in BM and PB, platelets, Smig, lymph node, spleen, liver, pattern of bone marrow infiltration, therapy free interval, and overall survival were all compared. Significant correlations between the presence of clonal abnormalities and prior therapy (p less than 0.005) and an increase in prolymphocytes in bone marrow (p = 0.05) and/or peripheral blood (p = 0.0014) were observed.
Leukemia 1989 Mar
PMID:Chromosome abnormalities in B cell chronic lymphocytic leukemia and their clinical correlations. 291 55

The frequency of Burkitt lymphoma-leukemia (BL) is high in patients with acquired immunodeficiency syndrome (AIDS). We describe four such cases, three with a translocation t(8;14)(q24;q32) and one with a t(8;22)(q24;q11). No Epstein-Barr virus genome was found in the tumorous cells of this patient. Including these cases, 13 patients with AIDS-associated BL have been reported so far with specific translocations. Three had a t(8q+; 22q-) variant translocation and the other ten patients had the t(8q-; 14q+). Associated chromosomal abnormalities were as frequent as in ordinary BL and were comparable with those occurring in cases of other BL, such as partial duplication of 1q and 13q34 rearrangements. Trisomy 12, however, was observed in 3 out of 13 AIDS-associated BL cases.
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PMID:Cytogenetic studies of Burkitt lymphoma-leukemia in patients with acquired immunodeficiency syndrome. 316 8

We studied the B lymphocyte metaphases in 78 of 94 cases of CLL, 24 of our 28 hairy cell leukaemias, 4 CLL's which transformed into prolymphocytic leukaemia and 8 original prolymphocytic leukaemias. Twelve CLL's were carriers of trisomy 12, 13 of this trisomy 12 with other abnormalities and 15 had other abnormalities without trisomy 12. Trisomy 12 seemed to be more frequent in patients with CLL or prolymphocytic leukaemia with a monoclonal gammopathy. In contrast to our previous results, the isolated finding of a trisomy 12 had an influence on the median survival.
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PMID:Cytogenetic studies in chronic lymphocytic leukemia, prolymphocytic leukemia and hairy cell leukemia: a progress report. 322 49

Trisomy 12 and a deletion of chromosome 13 are the most common chromosome abnormalities in patients with B cell chronic lymphocytic leukemia (B-CLL). We determined the frequencies of these abnormalities in Japanese B-CLL patients by FISH in interphase nuclei. Specimens from 42 patients were analyzed using both DNA probes specific to the centromeric region of chromosome 12 and the retinoblastoma (RB) gene. Among 42 patients, eight had trisomy 12 and 12 had the RB gene deletion. We found aberrations of trisomy 12 and the RB gene deletion in a totally different group of patients. This suggested that the trisomy 12 and the RB gene deletion occur in different clones and the presence of which in the same patient may be rare. Furthermore, the frequency of trisomy 12 (19%) found in Japanese B-CLL was lower than that in Western countries (30-35%). On the contrary, the frequency of the RB gene deletion (28.6%) was almost the same as in European B-CLL (30-35%). These results will be helpful in understanding the leukemogenesis of B-CLL.
Leukemia 1995 Nov
PMID:Independent clones of trisomy 12 and retinoblastoma gene deletion in Japanese B cell chronic lymphocytic leukemia, detected by fluorescence in situ hybridization. 747 69

Chromosome analysis of more than 1200 patients with chronic lymphocytic leukaemia reported to the International Working Party on Chromosomes in CLL and in the literature is analysed. Clonal chromosomal abnormalities are found in about half of the patients, and one third of those with clonal aberrations have trisomy 12, with or without additional changes. The most common structural abnormalities involve the long arm of chromosome 13, usually as deletions involving 13q14, the site of the retinoblastoma gene. Other recurrent abnormalities are deletions of the long arms of chromosome 11 and 6. 14q+ markers are frequent in patients at advanced stage, but are almost always within complex abnormalities. The number of clonal abnormalities in the CLL cells has a strong prognostic impact. Trisomy 12 as a single abnormality is an adverse prognostic sign, whereas patients with 13q abnormalities generally do comparatively well. Lymphoid leukaemia with monoclonal immunoglobulin secretion frequently involves clonal chromosomal abnormalities, and the type of change is similar to that seen in true CLL. In B cell prolymphocytic leukaemia, t(11;14) is a common finding, together with trisomy 12. T cell prolymphocytic leukaemia is characterized by an inversion of the long arm of chromosome 14, with breaks at q11 and q32, and trisomy of 8q, whereas large granular lymphocytic leukaemia has shown no consistent abnormality. Hairy cell leukaemia seems to involve a specific set of non-random chromosome abnormalities, such as inv(5)9.
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PMID:Cytogenetics in CLL and related disorders. 803 92

Trisomy 12 has been shown to be one of the most common chromosome abnormalities in chronic lymphoid leukemias of B-cell origin, and some studies suggested that it predicts poor overall survival. We have prospectively studied 42 patients with B-cell chronic lymphocytic leukemia (B-CLL) and three patients with B-prolymphocytic leukemia (B-PLL) for the incidence of trisomy 12 and other chromosome 12 aberrations applying fluorescence in situ hybridization (ISH) and conventional G-banding analysis. Dual-color hybridization experiments using centromere-12-specific DNA probes were performed for interphase cytogenetics. A subset of patients (n = 11) was analyzed using a DNA library for painting of chromosome 12. The incidence of trisomy/partial trisomy 12 was 18% (8/45 patients; 6/42 with B-CLL and 2/3 with B-PLL) by fluorescence ISH, and 11% (5/45 patients; 4/42 with B-CLL including one patient with partial trisomy 12q13-qter, and 1/3 with B-PLL) on G-banding analysis. Four patients with trisomy 12 were detected by ISH alone. One of these patients only had 4.5% interphase cells with three fluorescence signals indicating the presence of a small subclone with trisomy 12. On G-banding analysis, three of the four patients had a normal karyotype, and one patient had no analyzable metaphases. In conclusion, fluorescence ISH to interphase nuclei is a sensitive method for detecting trisomy 12 in patients with chronic lymphoid leukemias.
Leukemia 1993 Apr
PMID:Trisomy 12 in chronic lymphoid leukemias--a metaphase and interphase cytogenetic analysis. 846 29

Cytogenetic analysis of patients with chronic B-cell leukemia (B-CLL) indicates that 50% have chromosome abnormalities, while fluorescence in situ hybridization (FISH) and molecular techniques reveal an even higher incidence. Trisomy 12 and deletions or translocation of chromosome 13q14 are the most common abnormalities, but in neither case has the gene or genes involved in the abnormalities been identified. Combined FISH and immunophenotyping studies suggest that both abnormalities are secondary events in B-CLL. Other recurring chromosome abnormalities include 6q-, 11q- and 12p-, but the genes involved in these abnormalities have not been identified. Involvement of the BCL1, BCL2, and BCL3 genes has been reported, but the numbers are low and the cases tend to be atypical. Trisomy 12 in association with complex karyotypic abnormalities is associated with a poor prognosis, and FISH studies show a strong correlation between trisomy 12, atypical morphology, and advanced disease. Ten to 15% of patients have mutations of p53 which is associated with advanced disease, resistance to treatment, and poor survival.
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PMID:Genes and chromosomes in chronic B-cell leukemia. 907 90


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