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Cytogenetic analysis has strong independent prognostic value in de novo myelodysplastic syndromes and can be incorporated in a new scoring system: a report on 408 cases.

Although the prognostic value of cytogenetic analysis has previously been demonstrated in myelodysplastic syndromes (MDS), karyotype had not been included in previously published scoring systems, such as Bournemouth and Sanz's scores. We studied karyotype at diagnosis in 408 cases of de novo MDS (after excluding therapy-related MDS). Karyotypes were classified in 10 groups: normal; isolated del 5q; del 5q and other rearrangements; isolated +8; isolated -7 or del 7q; del 20q; isolated -Y; miscellaneous single rearrangements; -7 or del 7q and other rearrangements; miscellaneous complex rearrangements. Karyotypes were considered complex when at least three chromosomes were rearranged. Complex karyotypes included all patients with del 5q and other rearrangements, -7 or del 7q and other rearrangements, and miscellaneous complex rearrangements (i.e. three of the 10 groups). Median actuarial survival of the 408 patients was 28 months, and 90 patients (22%) progressed to acute myeloid leukemia (AML). For survival, bone marrow (BM) blasts, circulating blasts, white blood cell (WBC), neutrophil count, platelet count, hemoglobin, age, sex, FAB classification, and Bournemouth and Sanz's scores had strong prognostic value. Cytogenetics also had strong prognostic value. An unfavorable cytogenetic group (patients with complex karyotypes) was identified. On the other hand, although patients with isolated del 20q and del 5q had a somewhat better prognosis than other patients with non-complex cytogenetic findings, they could not be statistically individualized as a favorable group, possibly owing to their relatively limited number. By multivariate regression analysis, a three-variable new scoring system could be designed based on karyotype (1 point for complex karyotype; 0 for other groups), platelets (0 for > 75 x 10(9)/l; 1 for < 75 x 10(9)/l), and BM blasts (0 for < 5%, 1 for 5-10%, 2 for > 10%). The total score (addition of points for the three variables) was able to separate patients in three groups with low (score 0) intermediate (score 1 or 2), and high risk (score 3 or 4) which included 34%, 47%, and 19% of the patients, and had a median survival of 55, 24, and 6 months, respectively (chi 2 = 110, p < 10(-4)). This new score (Lille score) was able to subdivide risk groups according to Bournemouth and Sanz's scores into further subgroups of different prognoses. For progression to AML, BM blasts, circulating blasts, WBC count, hemoglobin, FAB type, and karyotype had prognostic value by univariate analysis.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗

Abberant cytogenetic evolution pattern of Philadelphia-positive chronic myeloid leukemia treated with interferon-alpha.

The cytogenetic evolution of 32 Philadelphia (Ph)-positive chronic myeloid leukemias (CML) receiving interferon-alpha (IFN-alpha) therapy was compared to the patterns in untreated CML and cases treated with busulfan (Bu), hydroxyurea (Hy), and allogeneic bone marrow transplantation (BMT). Half of the CML receiving IFN-alpha had at least one of the well-known major or minor route aberrations whereas 16 cases displayed unusual secondary abnormalities, of which only del(7p) and del(13q) were recurrent; a frequency significantly higher than in CML without therapy or after Bu and Hy treatment (P < 0.001) but similar to the one found post-BMT. The incidence of cases with cytogenetically divergent subclones, ie cell populations with unrelated aberrations in addition to the t(9;22), was also higher in the IFN-alpha group compared to the untreated, Bu and Hy groups (P < 0.01) but similar to the post-BMT group. Finally, 14 of the 32 IFN-alpha-treated CML displayed cytogenetic evolution already during the chronic phase; again a higher incidence than in the untreated, Bu and Hy groups (P < 0.001) but not different from the post-BMT group. These findings strongly indicate that IFN-alpha, directly or indirectly, can induce clones with aberrant chromosomal evolution patterns to evolve and proliferate, but the mechanisms underlying these cytogenetic peculiarities remain to be elucidated.

Adult↗

Breast cancer cytogenetics: a review and proposal for clinical application.

Cytogenetic analyses of hematological neoplasms have proved to be relevant in the diagnosis, treatment, and prognosis of afflicted patients. Breast cancer (BC) cytogenetics is expected to contribute in the same fashion. Literature has shown that clone-specific chromosomal changes do occur in BC, yet, their clinical significance is unknown. Most of the studies have been conducted on patients with advanced stage tumor. Karyotypic analyses of the few reported cases from stage I BC tumors revealed a higher frequency of single clonal abnormalities. This work describes an ongoing BC cytogenic study on samples from stage I tumors to enhance and clarify this observation. Included as control are chromosomal analyses of peripheral blood and peritumoral normal tissue samples of these patients, which might provide information regarding predisposing cytogenetic aberrations. Non-random chromosomal abnormalities in BC include involvement of chromosomes 1, 3, 6, 11, 16, and 17. Three groups of non-random chromosomal alterations, ranging from specific abnormalities, partial monosomies, and secondary changes (eg, numerical loss of chromosomes) are described. Survival appears to be more favorable in patients without complex karyotypes. A better understanding of the clinical and etiologic implications of BC is expected to emerge from continued assessment of breast tumor cytogenetics.

Breast Neoplasms↗

[Complete cytogenetic remission of chronic myeloid leukemia with low-dose interferon alfa-2b and monthly high-dose busulfan].

Two patients with chronic myelogenous leukaemia were treated according to an original regimen consisting of the association of alpha-2b interferon, three days a week, plus hydroxyurea during ten months, followed by interferon (same doses) and intermittent high doses of busulphan (50 mg, one dose per month, up to 6 doses). Both patients achieved minor cytogenetic remission in the first stage (50% and 80% of Ph'-positive metaphases, respectively). Upon concluding the second phase, one patient attained complete cytogenetic remission and the other showed major cytogenetic remission (3% Ph'-positive metaphases); complete remission was achieved in the second patient after 4 more doses of busulphan. Both patients remain in complete cytogenetic remission after 4 and 2 years, respectively, with three weekly doses of interferon as maintenance therapy. This protocol is quite different to others applied so far and might represent a good choice for patients unsuitable for bone marrow transplantation.

Adult↗

[Cytogenetic abnormalities as prognostic factors in acute myeloid leukemia].

UNLABELLED: The study of chromosomal abnormalities in AML has become very important in the diagnosis and in the characterization of subtypes since they are related to defined clinical, morphological and immunological features as well as treatment outcome and survival. PURPOSE: To evaluate the relative importance of cytogenetic abnormalities may have in AML patients. METHODS: 13 AML patients were studied during diagnosis. Cytogenetic study was performed on bone marrow aspirate material. RESULTS: M1 and M2 FAB subtypes were the most frequent (61.6%). The patients' median age was 38 years. Cytogenetic analysis showed abnormal karyotype in 61.5% of the cases and 15.3% of whom had abnormalities considered as good prognosis [t(15;17) and t(8;21)]. At the evaluation day there were 3 patients alive, two in continuous complete remission and 1 in a second remission. The median total survival time was 7 months. Patients were divided into two groups: a "good prognosis" one, that joined 5 patients with normal karyotype and 2 with the translocations t(15;17) and t(8;21) and another, the "bad prognosis" one, with 8 patients with unfavorable chromosomal abnormalities. The good prognosis group had a median survival time of 9 months versus 6.2 months in the other, but this was not statistically significant (p = 0.18), probably owing to the small number of cases in the groups. But when one observes the cases separately see that patients with translocations (8;21) and (15;17), known as good prognosis, had longer survivals. CONCLUSION: The different survival time between the two groups showed the importance of cytogenetic study to distinguish the patient who will have favorable evolution.

Acute Disease↗

Rearrangement of ALL1 (MLL) in acute myeloid leukemia with normal cytogenetics.

Approximately 45% of adults with acute myeloid leukemia (AML) have normal cytogenetics and therefore lack structural abnormalities that can assist in the localization and characterization of molecular defects. The partial tandem duplication of the ALL1 (MLL) gene has been found in several such cases of AML, yet its frequency and clinical significance are unclear. We performed Southern analysis of the ALL1 gene in pretreatment samples from 98 AML patients with normal cytogenetics. Eleven of 98 such patients (11%; 95% confidence interval, 6-19%) showed rearrangement of ALL1 at diagnosis. The partial tandem duplication of ALL1 was responsible for ALL1 rearrangement in all such cases examined, making it a frequent molecular defect in adult AML patients with normal cytogenetics. Furthermore, patients with ALL1 rearrangement had a significantly shorter duration of complete remission when compared to patients without ALL1 rearrangement (P = 0.01; median, 7.1 versus 23.2 months). This defect defines for the first time a subset of AML patients with normal cytogenetics who have short durations of complete remission and thus require new therapeutic approaches.

Acute Disease↗

Combined metaphase, interphase cytogenetic, and flow cytometric analysis of DNA content of pediatric acute lymphoblastic leukemia.

Eleven pediatric acute lymphoid leukemia patients were investigated for chromosomal aneuploidy by interphase cytogenetics using chromosome specific (peri)centromeric probes for all the somatic and sex chromosomes. Results were compared with metaphase cytogenetic and flow cytometric derived DNA aneuploidy data. Experiments performed on normal human cells using chromosome specific (peri)centromeric probes indicated that disomy could be recognized in a range of 89.1+/-2.7% (12.9)-96.8+/-0.2% (0.9) for the somatic chromosomes and in 98.1+/-0.4% (1.3) for the sex chromosomes. Using the cutoff level of the mean false monosomy and trisomy in the control cells +2 S.D., chromosome loss or gain for the somatic chromosomes could be revealed beyond a clonal ratio of 3.6-13.2% and 1.1-6.8%, respectively. The same value for the sex chromosomes was 3.5% and 0%, respectively. In 5 of 11 patients the leukemic cells proved to be diploid with all three methods at both gross DNA and chromosome levels. Interphase cytogenetics revealed chromosome loss or gain in all of the remaining six patients, however, the metaphase analysis indicated numerical aberration in only two patients. In one of them only the increased chromosome number could have been detected without identifying the chromosomes involved and in the other one the two methods indicated trisomy for a different chromosome. Flow cytometric data showed aneuploidy in three of the six aneuploid leukemia patients. The results suggest that interphase cytogenetics might be more accurate compared with flow cytometry and metaphase analysis to reveal aneuploidy.

Adolescent↗

Molecular cytogenetic alterations in the early stage at human bronchial epithelial cell carcinogenesis.

Lung carcinogenesis is a multi-step process involving activation of oncogenes and inactivation of tumor suppress genes. Many molecular and cytogenetic alterations occur in the early stages of carcinogenesis. We have developed an effective culture system for human bronchial epithelial cells and lung cancer cells. Four immortalized human bronchial epithelial cell lines were established by transfecting the epithelial cells with plasmid DNA containing the early region of SV40. Some molecular and cytogenetic alterations, such as 3p-, 2q-, 9p-, c-myc translocation t(8;14) (q23; q32), were found in one immortalized bronchial epithelial cell line M when approaching malignant transformation. An increase in cell proliferation and decrease of apoptosis were noted in the late passages of the immortalized cell line M. Some molecular cytogenetic alterations were also observed in human primary non-small cell lung cancers. Molecular cytogenetic alterations during the early stage of carcinogenesis of human bronchial epithelial cells may be useful as biomarkers for both diagnosis and intermediate endpoint of chemoprevention of lung cancer.

Animals↗

Correlation of cytogenetic abnormalities with the outcome of patients with uveal melanoma.

BACKGROUND: Cytogenetic investigations of choroid and ciliary body melanomas have revealed that the majority of cases are characterized by recurrent clonal abnormalities involving chromosomes 3, 6, and 8. The authors sought to determine whether these abnormalities were associated with outcome. METHODS: Fifty-four patients who underwent enucleation for untreated uveal melanoma between 1988 and 1996 were subjected to complete cytogenetic analysis. The most recent follow-up data from the time of enucleation was obtained. Patient outcomes were divided into two groups: 1) alive with metastases or dead of disease, and 2) alive without known metastases or dead of other causes. The relative risk (RR) and 95% confidence interval (CI) of a poor outcome were calculated for each chromosomal abnormality and clinical characteristic. RESULTS: Patients were followed for a median of 38 months. No patients were lost to follow-up. Abnormalities of chromosomes 3 and 8 were associated with a poor prognosis, but only when these two chromosomal abnormalities were present together (RR = 4.1, 95% CI = 1.7-9.9). The presence of a chromosome 6 abnormality was predictive of a good outcome (RR = 0.2, 95% CI = 0.1-0.8), even in the presence of chromosome 3 and 8 abnormalities. The only clinical factor associated with a poor outcome was the presence of extrascleral extension. CONCLUSIONS: In this group of patients with large posterior uveal melanomas, the concurrent presence of cytogenetic abnormalities of chromosomes 3 and 8 was associated with a poor outcome. An abnormality of chromosome 6 appeared to have a protective effect. These data suggest that cytogenetic analysis may provide prognostic information on patients with uveal melanoma and that further investigation of the contributions of these chromosomal aberrations to disease progression is warranted.

Chromosome Aberrations↗

[An analysis of the cytogenetic sequelae of chronic low-dose irradiation in plantings of agricultural crops].

There is a tendency for a decrease in the yield of cytogenetic disturbances with time elapsed from the Chernobyl accident. But an increased rate of cytogenetical damages significantly dependent on the level of radioactive contamination was observed even in several years after the incident. The rate of decline with time in cytogenetic disturbances induced by chronic exposure considerably lagged behind that of radiation exposure. Analysis of genetic changeability in three sequential generations of winter rye and wheat revealed increased cytogenetic damage in crops grown on contaminated sites during 2 and 3 years.

Chromosome Aberrations↗

[The cytogenetic indices of participants in the cleanup of the aftermath of the accident at the Chernobyl Atomic Electric Power Station and their correction].

An analysis was performed of cytogenetic homeostasis in liquidators of the Chernobyl accident after-effects, which led to the belief that if the above contingent of subjects continue living in large industrial regions characterized by high levels of environmental contamination with industrial waste, such as that formed in the chemical, by-product coke, and metallurgical industries, they will not dispel disorders of the cytogenetic homeostasis (chromosomal and chromatic aberrations), which fact is believed to be due to the inhibition of the processes of elimination of somatic cells with a faulty genotype. Proposed for the correction of cytogenetic disorders are such options as a complex of antioxidants and intravascular laser irradiation of blood, that will, we believe, help in restoring the cytogenetic homeostasis.

Adult↗

Advances in cancer cytogenetics.

As the end of the millenium approaches, recognition of the milestones achieved in the field of cancer cytogenetics is mandatory. With regard to cancer cytogenetics, the turning century can be divided in three main era: the pre-banding period that has posed important hypothesis and technical premises, the fruitful banding era that led to the discovery of the critical chromosomal rearrangements and cloning of cancer genes and the more recent revolutionizing era of molecular cytogenetics where technological advances permit a global visualization and high-level resolution of chromosomal alterations. J. Cell. Biochem. Suppls. 32/33:173-182, 1999.

Animals↗

The new cytogenetics: blurring the boundaries with molecular biology.

Exciting advances in fluorescence in situ hybridization and array-based techniques are changing the nature of cytogenetics, in both basic research and molecular diagnostics. Cytogenetic analysis now extends beyond the simple description of the chromosomal status of a genome and allows the study of fundamental biological questions, such as the nature of inherited syndromes, the genomic changes that are involved in tumorigenesis and the three-dimensional organization of the human genome. The high resolution that is achieved by these techniques, particularly by microarray technologies such as array comparative genomic hybridization, is blurring the traditional distinction between cytogenetics and molecular biology.

Chromosome Aberrations↗

Molecular cytogenetics.

Refinements in cytogenetic techniques over the past 30 years have allowed the increasingly sensitive detection of chromosome abnormalities in haematological malignancies. In particular, the advent of fluorescence in situ hybridization techniques has provided significant advances in both diagnosis and research of leukaemias. The application of new multicolour karyotyping techniques has allowed the complete dissection of complex chromosome rearrangements and provides the prospect of identifying new recurrent chromosome rearrangements. Both comparative genomic hybridization and interphase fluorescence in situ hybridization avoid the use of metaphase chromosomes altogether and have allowed the genetic analysis of previously intractable targets. Recent developments in comparative genomic hybridization to DNA microarrays provide the promise of high resolution and automated screening for chromosomal imbalances. Rather than replacing conventional cytogenetics, however, these techniques have extended the range of cytogenetic analyses when applied in a complementary fashion.

Cytogenetic Analysis↗

Cytogenetic analyses of Arabidopsis.

For a long time, Arabidopsis thaliana was not a favorite of cytogeneticists because of its small chromosomes. Nevertheless, most cytogenetic approaches have become applicable to this model plant during the past decade. Recently, the very small genome, the low content, and strong clustering of repetitive sequences even turned out to be advantageous for the first establishment of chromosome painting in a euploid plant. Chromosome painting together with the high-resolution fluorescence in situ hybridization (FISH) mapping on Arabidopsis pachytene chromosomes has opened new perspectives for plant cytogenetics. In this chapter, we describe standard cytogenetic methods including preparation of chromosomes and chromatin fibers, isolation of interphase nuclei, FISH and immunostaining, painting of Arabidopsis chromosomes, and comparative chromosome painting in other Brassicaceae species.

Arabidopsis↗

Molecular cytogenetic characterization of a novel cell line established from a superficial spreading melanoma.

We report the complex cytogenetic analysis of a novel melanoma cell line (M35/01) established from a vertical growth phase of a superficial spreading melanoma. Similarly to its parental tumor, this cell line metastasizes to the liver. Using combined molecular cytogenetic techniques, we could identify a reservoir of chromosomal alterations in M35/01. In addition, we had sufficient amount of DNA from both the original primary tumor and the cell line which allowed for the comparison of their genetic patterns by chromosomal CGH. Several common alterations were found indicating the same clonal origin. These alterations included gains of 6p, 7q, 15q and deletions of 9, 10, 16q and 17p. Chromosomal losses present only in the cell line were detected on chromosome 4, 16p, 18 and gains on 20p12-qter. Array CGH analysis of the M35/01 cell line provided similar results with a much higher resolution, representing relatively high level gains on 7q31.2-q31.31, 15q25, 20q, and losses on 4q28, 9p21-p24, 9q21-q22, 10q25, 16q13-q23, 17p12-13 and 18q12-23. Using SKY-FISH, several structural alterations could be detected which were not recognized by conventional cytogenetics. Except for chromosome 18, none of the centromeres showed normal distribution by FISH. Our analysis shows that a high number of chromosomal alterations, which are known to be nonrandomly associated with melanoma progression, can be found by the combined use of different molecular genetic techniques. This new melanoma cell line would be an excellent model for investigating the mechanism of organ specific-metastatic events of malignant melanoma.

Aged↗

Human cytogenetics. A current overview.

Chromosomal abnormalities are the basis for a substantial proportion of human morbidity and mortality. During the past 35 years, the field of human cytogenetics has helped to elucidate the etiology of many congenital malformation/mental retardation syndromes. Through adaptation of technological advances and integration of molecular biological techniques, cytogenetics continues to contribute significantly to our knowledge of clinical genetics, chromosomal fine structure and function, gene mapping, and prenatal diagnosis. This review outlines the basic concepts, recent findings, and current laboratory approaches to cytogenetic diagnosis.

Amniocentesis↗

Cytogenetic studies on fine-needle aspiration samples from osteosarcoma and Ewing's sarcoma.

The preoperative multidrug chemotherapy of osteosarcoma and Ewing's sarcoma patients requires a reliable diagnosis. There are several advantages with obtaining the diagnosis by fine-needle aspiration (FNA) and cytologic examination. Although cytologic criteria have been defined, adjunctive methods such as cytogenetic analysis are valuable to support the diagnosis. We have cytogenetically analyzed FNAs from 18 primary bone sarcomas (six osteosarcomas and 12 Ewing's sarcomas). Two of the osteosarcomas showed abnormal, complex karyotypes seen in most highly-malignant osteosarcomas. Seven Ewing's sarcoma aspirates displayed abnormal karyotypes; five of these had the characteristic 11;22 translocation, and in one of these cases molecular genetic analysis revealed the hybrid EWS/FLI1 transcript. Since only two of six osteosarcomas showed clonal changes, chromosomal analysis of FNAs from suspected osteosarcoma seems to be of limited value, but may in some cases support the diagnosis of high-grade malignancy. In Ewing's sarcomas, however, the finding of an 11;22 translocation was valuable and strongly supported the cytologic diagnosis. As shown in one case, the material obtained by FNA is sufficient for cytologic, cytogenetic, and molecular genetic analysis.

Adolescent↗