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Cytogenetic effects of pesticides. IV. Cytogenetic effects of the insecticides Gardona and Dursban.

The cytogenetic effects of the insecticides Gardona and Dursban were investigated. The toxicity and ability of both insecticides to induce chromosome aberrations and sister-chromatid exchange in vitro was tested in a primary culture of mouse spleen cells, in order to assess the potential mutagenicity of both insecticides. The concentrations 10(-7)-10(-3) M were used for testing the toxic effects of the insecticides. Both Gardona and Dursban were toxic to spleen cell cultures and the percentage of viable cells decreased as the concentration of the insecticide was increased. It reached 76.8% and 77.8% of control after treatment with the highest concentration tested (10(-3) M) of Gardona and Dursban respectively. Gardona at 0.25, 0.50, 1.0 and 2.0 micrograms/ml, and Dursban at 0.50, 1.0, 2.0 and 4.0 micrograms/ml were tested for the induction of chromosome aberrations and sister-chromatid exchanges. All of the tested concentrations of both insecticides induced a high percentage of metaphases with chromosomal aberrations in cultured mouse spleen cells after 4-h treatment. The frequency of SCEs/cell increased with increasing concentration of the insecticides. It reached 11.92 +/- 0.14/cell and 13.40 +/- 0.20/cell after treatment with Gardona (2 micrograms/ml) and Dursban (4 micrograms/ml), respectively, compared with 8.2 +/- 0.19/cell and 7.6 +/- 0.15/cell in the solvent control. The presented results indicate that both Gardona and Dursban in the tested concentrations are mutagenic in mouse spleen cell cultures.

Animals

Cytogenetics in malignant lymphoma.

There appear to be four primary areas of interest in the application of cytogenetic techniques to the study of malignant lymphomas: (1) the role of cytogenetics in the diagnosis of lymphoma in problem cases, (2) as an aid to the classification of malignant lymphomas, (3) whether specific chromosomal patterns will have prognostic significance for response to therapy or survival, and (4) the role of cytogenetics in staging of malignant lymphomas. A case of reactive lymphoid hyperplasia is reported in which cytogenetic studies demonstrated an aneuploid clone suggesting that cytogenetic abnormalities of lymphoma may precede the diagnostic histopathologic picture. The occurrence of 14q+ marker chromosomes in plasmacytic myeloma, plasma cell leukemia, malignant lymphomas, Burkitt's lymphoma, and ataxia-telangiectasia suggest that a common etiologic or pathogenetic mechanism may be present in some of these disorders. A preliminary pilot study of spleens removed at staging laparotomy for Hdgkin's disease suggests that cytogenetic studies may be able to detect Hodgkin's disease that is not apparent histologically. Further studies are required to provide answers to these areas of interest in cytogenetics in malignant lymphoma.

Chromosome Aberrations

Correlation of cytogenetic analysis and loss of heterozygosity studies in human diffuse astrocytomas and mixed oligo-astrocytomas.

The aims of this study were to correlate cytogenetic studies and molecular genetic loss of heterozygosity (LOH) analyses in human astrocytomas and mixed oligo-astrocytomas, and to locate putative tumor suppressor genes on chromosome 10. Paired blood and tumor samples from 53 patients were analyzed. The tumors included 45 diffuse astrocytomas (39 grade 4, 4 grade 3, and 2 grade 2), 1 astroblastoma, and 7 mixed oligo-astrocytomas (2 grade 4, 4 grade 3, and 1 grade 2). By cytogenetic analyses the most common numeric chromosome abnormalities were +7, -10, -13, -14, -17, +19, -22, and -Y. The most common structural abnormalities involved chromosome arms 1p, 1q, 5p, and 9p. By LOH and dosage analysis the most common molecular genetic abnormalities were of chromosome arms 5p, 6p, 7q, 9p, 10p, 10q, 13q, 14q, 17p, and 19p. When the results of all methods were combined, the most commonly abnormal chromosomes were, in descending frequency, 10, Y, 17, 7, 13, and 9. In 80 percent of cases the cytogenetic and molecular genetic studies were concordant. LOH studies were more sensitive in detecting loss of genetic material than cytogenetic analyses and accounted for 60% of the discordant results. When there were structural abnormalities, such as translocations or inversions, cytogenetic analysis was more sensitive in detecting an abnormality than molecular genetic studies. In addition to the 24 tumors which appeared to lose an entire copy of chromosome 10, there were 10 tumors with molecular genetic or cytogenetic evidence of loss of only a portion of chromosome 10. The genetic analyses of these tumors suggest that there are 2 regions on chromosome 10 that may contain potential tumor suppressor genes. One lies distal to locus D10S22 from 10q22 to 10qter, and the other lies proximal to locus TST1 on the 10q arm near the centromere or on the 10p arm.

Adult

Is cancer cytogenetics reducible to the molecular genetics of cancer cells?

Whether cancer cytogenetics can be reduced to the molecular genetics of cancer cells is a question that must be addressed in three domains, focusing on its ontological, methodological, and epistemological dimensions. The possibility of ontological reduction hinges on whether chromosomes have other important constituents than molecules. Although this must obviously be answered in the negative, it should be emphasized that both cytogenetic and recombinant DNA investigations provide us with very selective pictures of genomic organization. This is of concern because the higher order packing of DNA and its joining with other molecules to form chromosomal structures give rise to emergent properties, functional features that become manifest only at higher levels of complexity and that may not be deducible from the base pair composition of the DNA. A position of extreme methodological reductionism would in our context be that the best research strategy is always to investigate the genetic changes of tumor cells at the highest possible resolution level, as alterations of genes and, ultimately, as changes in DNA primary structure. There are two fundamental differences between cytogenetic and molecular genetic techniques that make this stance untenable. First, whereas cytogenetic investigations are open-framed (all chromosome aberrations are revealed), molecular genetic analyses are highly specific (only those aberrations are revealed that one tests for). Second, whereas the molecular approach determines the genotypic constitution of an idealized, average tumor cell, cytogenetic analysis is of real, individual cells. These may not necessarily be representative of the main population of the tumor, but at least whatever karyotypic differences exist between them are detected. Heterogeneity and clonal evolution within the tumor can thereby be assessed.(ABSTRACT TRUNCATED AT 250 WORDS)

Chromosome Aberrations

[Contribution of a hematologic cytogenetic laboratory to the diagnosis, classification and prognosis of various hematologic malignancies].

The presence of an haematological cytogenetic laboratory into a clinical unit allowed to realize a close collaboration between clinicians and cytogeneticists, and to achieve a maximal exploitation of the results of the bone marrow cytogenetic studies in some haematological malignancies. It made it possible to perform sequential bone marrow karyotypes studies during the different phases of a disease: We could thus establish: The diagnostic value of cytogenetic findings for chronic myelocytic leukaemia, secondary acute leukaemia, but not for dysglobulinemias. The prognostic value of cytogenetic abnormalities in chronic myelocytic leukaemia where additional abnormalities to the Ph1 are a hallmark of blastic transformation; in primitive dysmyelopoiesis where they represent a bad prognostic factor; in dysglobulinemias, where they are a signal of terminal evolution. In all these diseases, only complex and multiple abnormalities have a prognostic significance pointing out the emergence of a malignant clone, where as rare and single abnormalities are of no significance. Nowadays, haematological cytogenetic must be bound to molecular biology.

Cytogenetics

Genetic and cytogenetic studies of four glycolytic enzymes in Drosophila melanogaster: aldolase, triosephosphate isomerase, 3-phosphoglycerate kinase, and phosphoglucomutase.

Four glycolytic enzymes in Drosophila melanogaster have been genetically and/or cytogenetically mapped. The structural gene for aldolase (Ald) has been genetically mapped to 3-91.5 and cytogenetically localized to 97A-B. Tpi, the structural gene for triosephosphate isomerase, has been genetically mapped to 3-101.3 and cytogenetically localized to 99B-E. Utilizing closer-flanking markers than the previous mapping, Pgk, the structural gene for 3-phosphoglycerate kinase, has been mapped to 2-5.9; cytogenetically it was found to lie in the interval between 22D and 23E3. The cytogenetic locataion of Pgm, the structural gene for phosphoglucomutase which has been located genetically at 3-43.4, was determined to be in 72D1-5.

Alleles

Intensive conventional chemotherapy can lead to a precocious overshoot of cytogenetically normal blood stem cells (BSC) in chronic myeloid leukemia and acute lymphoblastic leukemia.

Forty patients with Ph-positive blastic phase (BP) (28 patients) or chronic phase (CP)-CML (3 patients) and relapsed adult acute lymphoblastic leukemia (ALL) (9 patients) with cytogenetical translocations [t(8;14):2 patients; t(4;8):2 patients; t(4;11):3 patients; t(9;22):2 patients], received an intensive conventional chemotherapy. During early recovery from marrow aplasia, when WBC reached 0.3-1.5 x 10--9/L, peripheral blood stem cells (BSC) were collected by 4-8 leukapheresis consecutively. BSC collected from the 2/3 patients with CP-CML resulted Ph-negative and PCR negative. In 8 out of 26 BP-CML patients, BSC resulted Ph-negative and in two cases PCR negative. Of the nine ALL patients, 6 patients lost the cytogenetic translocations, one patient died during aplasia, two patients did not have cytogenetic modifications and died in few weeks of leukemia and one patient out of six responding patients relapsed before transplant. After complete recovery, 15 patients (BP-CML:8 patients; CP-CML:2 patients; ALL:5 patients) were subsequently given high-dose therapy (VP-16 +/- Cy+TBI in single dose) followed by reinfusion of "normal" BSC. Both the patients in CP-CML and 5/5 patients with ALL maintain clinical and cytogenetic remission; all the patients transplanted in BP-CML relapsed 5-18 months post-transplant. It is concluded that intensive conventional chemotherapy employed in CML and ALL can lead to a precocious overshoot of cytogenetically normal BSC.

Adolescent

Cytogenetic Diversity of Variant Philadelphia Translocations in Chronic Myeloid Leukemia.

INTRODUCTION: Chronic myeloid leukemia (CML) is a disease characterized by Philadelphia (Ph) translocations. These translocations can be classical or variant. The structural features and diagnostic implications of variant Philadelphia translocations remain incompletely defined, and they display considerable cytogenetic heterogeneity. METHODS: In this retrospective study, variant Ph translocations identified by conventional cytogenetic analysis and fluorescence in situ hybridization (FISH) were systematically classified among 639 patients diagnosed with CML. A total of 35 patients with variant Ph translocations were included in the analysis. Molecular follow-up data, when available, were assessed using RT-qPCR analyses in a subset of patients. RESULTS: Chromosome analysis revealed 2 simple and 33 complex variant Ph translocations. FISH analysis, performed in 20 patients, identified deletions involving BCR, ABL1, or both in a limited number of cases. Additional chromosomal abnormalities and secondary translocations accompanied variant Ph translocations in four patients. The partner chromosomes involved in variant Ph translocations showed marked diversity, involving multiple chromosomal loci. CONCLUSION: Variant Philadelphia chromosome translocations in CML exhibit substantial cytogenetic diversity, reflecting the complexity of their underlying genomic architecture. The rarity and heterogeneity of these rearrangements complicate their classification and interpretation in routine diagnostic practice. Descriptive reporting of variant Ph translocations may contribute to a better understanding of their diagnostic complexity and support more accurate cytogenetic interpretation in CML.

Humans

Prenatal cytogenetic diagnosis: first 1,000 successful cases.

From February 1969 to August 1976, we studied 1,048 amniotic fluids. Of these, 958 (91.4%) were primarily for prenatal cytogenetic diagnosis. Cytogenetic studies were attempted in 1,021 cases; the diagnosis was successful in 1,000 of these. The failure rate of obtaining a diagnosis from the amniotic fluid cell culture of the first amniocentesis was 5% (50 cases); 29 cases had a repeat tap and successful diagnosis was achieved in all. In 21 cases, a repeat tap was refused. Thus, the overall failure rate of obtaining a final cytogenetic diagnosis was 2.06% (21/1,021). There were 32 fetal losses after amniocentesis including 16 spontaneous second trimester abortions, 7 fetal deaths in utero and 9 stillbirths. In two additional cases, fetal death had occurred before amniocentesis. This number of fetal losses does not exceed the number that would be expected in the same maternal age group without amniocentesis. In our series, the frequencies of trisomy in maternal age groups 40 years and over, 37-39 years, 35-36 years, and under 35 years were 4.5, 3.14, 0 and 0% respectively. These frequencies are comparable to those reported from other prospective prenatal studies and higher than those of retrospective live born studies. Various problems and pitfalls in prenatal cytogenetic diagnosis are discussed.

Adult

Cytogenetic abnormalities in an ossifying fibroma from a patient with bilateral retinoblastoma.

Cytogenetic analysis of a cemento-ossifying fibroma from a patient with nonfamilial bilateral multicentric retinoblastoma revealed three reciprocal translocations with the karyotype 46,XY,t(1;18)(q21;q21.3),t(3;10)(p13;q22),t(6;11)(p22;p15). Routine and high-resolution cytogenetic analysis of peripheral blood leukocytes showed an apparently normal, 46,XY chromosome pattern with no deletion of chromosome 13. Molecular analysis demonstrated no gross differences in the retinoblastoma gene or the TP53 gene between constitutional and tumor DNA. This is the first cytogenetic analysis of a cemento-ossifying fibroma and the first report of this tumor in a retinoblastoma patient. The data may be added to the small, but growing literature on cytogenetic aberrations in benign tumors and may lend insight into genes involved in cell proliferation and neoplastic transformation.

Adolescent

Clinical impact of chromosome 1 aberrations in neuroblastoma: a metaphase and interphase cytogenetic study.

Neuroblastoma tumors are characterized by aberrations of chromosome 1. Rapid detection of these chromosomal aberrations at diagnosis could give important clues to outcome and therapy. We attempted to detect numerical and structural aberrations of chromosome 1 not only by classical metaphase cytogenetics but also by interphase cytogenetics in order to overcome difficulties of karyotyping due to diminished metaphase quality and quantity in primary neuroblastoma samples. Karyotypic changes of chromosome 1 in 53 primary neuroblastomas were evaluated. In addition, we successfully performed interphase cytogenetics using single and double in situ hybridization procedures with chromosome 1-specific repetitive DNA probes on nuclei preparations obtained from 46 and 20 tumors, respectively. Polysomies of structurally normal chromosomes 1 were predominantly seen in tumors with good prognosis, whereas deletions of 1p material were nearly exclusively confined to progressive tumors. Numerical and structural chromosome 1 aberrations as studied by metaphase and interphase cytogenetics are thus valuable prognostic markers in neuroblastoma.

Chromosome Deletion

Cytogenetic and survival adaptive responses in G1 phase human lymphocytes.

Human lymphocytes from six donors were treated with 5 cGy of X-rays followed by 200 or 400 cGy in the first G1 phase after PHA stimulation, and assayed for cytogenetic aberrations and cell survival. Four donors showed cytogenetic adaptive responses with 400 cGy, and one with both 200 cGy and 400 cGy. Both exchanges and deletions were reduced, indicating that the cytogenetic adaptive response acts by restitution of chromosome breaks. Good correlations were found between nonaberrant cells and survival, although the former were often higher than the later, especially with the 400 cGy dose. In four of six donors, 5 cGy alone had significant effects on cell survival; however, this was independent of the 5 cGy effect on high-dose-induced responses. Two donors had survival adaptive responses with 5 + 200 cGy, while none were found with the 5 + 400 cGy treatment. The comparisons between the cytogenetic and survival responses suggests that a survival adaptive response will only be seen with a sufficient increase in nonaberrant cells. To date, adaptive responses to ionizing radiation have been reported to occur in G0, G1 and late S/early G2 human lymphocytes.

Adaptation, Physiological

Griseofulvin-induced aneuploidy and meiotic delay in female mouse germ cells. II. Cytogenetic analysis of one-cell zygotes.

The effects of griseofulvin (GF) upon the first meiotic division of female mouse germ cells were evaluated by cytogenetic analysis of first-cleavage (1-Cl) zygotes. The present study is an extension of an investigation that began with the cytogenetic analysis of metaphase II (M II) oocytes. Different doses (200, 666, 1332, 2000 mg/kg) were tested by oral administration of GF to superovulated animals either at the time of human chorionic gonadotrophin (HCG) injection or 2 h post HCG. When GF was given at the time of HCG, significant dose-dependent increases of different types of cytogenetically abnormal cells were found. These included zygotes containing ostensibly female-derived M I or M II arrested chromosomes and polyploid zygotes. The total yields of these aberrations were 2.9, 4.3, 26.2, 60.6, and 64.1% for control, 200, 666, 1332, and 2000 mg/kg, respectively. The origin of these zygotes was attributed to the fertilization of oocytes that had been previously arrested at M I. No significant induction of hyperploidy was detected. Developmentally abnormal zygotes were still observed when GF was administered 2 h post HCG, although their frequencies were significantly lower than in the first series of experiments. The yields of developmentally abnormal zygotes were 49, 10.2, and 23.6% at 200, 666, and 2000 mg/kg. Additionally, a dose-dependent increase in the frequency of hyperploid zygotes was detected up to a maximum of 36.5% at 2000 mg/kg. These results confirm the cytogenetic observations from M II oocytes after GF treatment under the same experimental conditions; namely, a dramatic change in the oocyte target susceptibility to GF occurred within a short time period. Also, the present study demonstrated that most of GF-induced aneuploid oocytes were fertilized and reached first-cleavage metaphase.

Aneuploidy

Cytogenetic analysis of hematologic malignancies in Hong Kong. A study of 98 cases.

The karyotypes of 98 patients between the ages of 8 and 81 years with acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), myelodysplastic syndromes (MDS), and chronic myeloid leukemia (CML) are presented. Although the well-described cytogenetic abnormalities associated with particular FAB subtypes in the West were observed, certain important local differences were noted. In ALL, hyperdiploidy was rarely observed, whereas the Philadelphia chromosome was observed in 50% of abnormal karyotypes. In AML, the t(8;21) was infrequently observed in M2 case, whereas trisomy 4 and 6, rarely reported elsewhere, formed 12% of the abnormal cases. In MDS, the incidence of -5/5q- and/or -7/7q- was 83% of cases with aberrant cytogenetic findings. Neither i(17q) nor an extra Ph was seen in 26 cases of CML including 9 cases of accelerated phase/blast crisis. In addition, previously unreported cytogenetic abnormalities occurring as single cases are presented. These findings are discussed in the context of geographical heterogeneity of chromosomal abnormalities in leukemia and emphasize the importance of continued epidemiologic studies of cytogenetics in hematologic malignancies.

Adolescent

[Cytogenetic effect of cyclophosphamide in a culture of human lymphocytes following its activation in the bodies of mice].

Cytogenetic effect of cyclophosphamide in cultured human lymphocytes after its activation in C57BL/6 mice in vivo was investigated. Cyclophosphamide was injected intraperitoneally in mice for 30 min. at doses of 200, 400, 600, 800 and 1000 mg/kg. Blood serum with activated metabolites of cyclophosphamide was added to human lymphocyte culture. The dependence of the part of aberrant metaphases on the concentration of cyclophosphamide after the activation can be presented as equation rho==1-e-(KC+alpha)2 and the total number of breaks as X=e(KC+alpha)2-1, where rho is a part of aberrant metaphases, X is a number of breaks of chromosomes per cell, C is the concentration, K and alpha are coefficients. The part of chromatid breaks from the total number of chromosome damages is constant for all concentrations and the comprises on the average 79,11%. Only the chromatid type of exchanges are observed. Distribution of chromosome breaks in cells corresponds to geometrical, but not to Poisson's distribution. Cyclophosphamide belongs to the group of one-sited mutagens in its cytogenetic chatacteristics. The alkylating activity of cyclophosphamide metabolites, estimated by means of NBP test, increases up to the dose 400 mg/kg and then remains constant for the strain of mice studied, cytogenetic activity increasing. Cyclophosphamide does not produce cytogenetic activity without activation. To test chemical substances for mutagenic activity, it is suggested to activate them in the mouse organism with the following administrating blood serum of these animals with the metabolites of tested (or with primary) substances in the study of their mutagenic activity on human lymphocyte culture.

Animals

Polyclonal hematopoiesis in interferon-induced cytogenetic remissions of chronic myelogenous leukemia.

Interferon (IFN) therapy of early chronic myelogenous leukemia (CML) frequently produces partial or complete cytogenetic remission of the disease. Patients with complete cytogenetic remission often continue on therapy for several years with bone marrow showing only diploid (normal) metaphases. We studied hematopoiesis in five female patients with major cytogenetic remissions from CML during IFN therapy. Clonality analysis using the BstXI PGK gene polymorphism showed that granulocytes were nonclonal in all patients during cytogenetic remission. BCR region studies showed rearrangement only in the one patient whose remission was incomplete at the time of sampling. Granulopoiesis is nonclonal in IFN-induced remissions of CML and may be derived from normal hematopoietic stem cells.

Clone Cells