Melita Nakić

Cytogenetic analysis of hepatoblastoma

A cytogenetic investigation was performed in a case of hepatoblastoma; the analyses revealed a pseudodiploid karyotype.

Cytogenetic analysis in ataxia telangiectasia with malignant lymphoma

We present the results of cytogenetic analysis in a brother and sister with ataxia telangiectasia (AT), one of whom had malignant T-cell lymphoma. In both children, cytogenetic analysis of phytohemagglutinin (PHA)-stimulated lymphocytes showed chromosomal instability and inv(7) in 10% of the cells examined. The malignant lymphoma was analyzed cytogenetically on slides obtained from short-term culture of the lymph node cells; 64 cells were analyzed. A heterogeneous cell population was noted. Fourteen cells (21.9%) had a normal male karyotype; t(7;14)(p14;q12) and inv(7)(p14q35) were observed in 6.3% and 3.1% of metaphases. Owing to low frequency, these cells are probably a characteristic of the basic disease and have no features of malignant cells. Forty cells (62.5%) had a pseudodiploid karyotype 46,XY,dup(1)(p22p36),del(5)(q33),del(12)(p11), without cytogenetically evident aberrations of chromosomes 7 and 14. The results of these investigations suggest that the cells with rearrangements of chromosomes 1, 5, and 12 are malignant cells and did not originate by transformation of cells with inv(7) and t(7;14).

Cytogenetic analysis in children with acute nonlymphocytic leukemia

In this work we present the results of cytogenetic analysis of the malignant cells in 27 children with acute nonlymphocytic leukemia (ANLL). The aim of our investigations was to determine the frequency and types of chromosome aberrations in our population of children with ANLL. Successful cytogenetic analysis was carried out in 24 (89%) patients. Aberrant karyotypes of malignant cells were established in 58% of the cases. The most frequent chromosomal abnormality was t(8;21), identified in 5 (20.8%) patients, i.e., 4 of 10 M2-ANLL. Aberration frequency of chromosome 11 was 16.6% and was identified in 3 of 8 M5-ANLL. Trisomy 8 and monosomy 7 were identified in one patient each with M3 and M2-ANLL, respectively. del(13), a rare chromosome aberration in hemoblastoses, was found in a child with M1,t(8;21) and the loss of chromosome Y. Translocation t(1;11;21) with a break in regions 1q23, 11q23, and 21q22, is unusual and was identified in a boy with M2-ANLL; it can be considered as a variant form of the t(8;21).

Variability of chromosomes 1, 9, and 16 in children with malignant diseases

Heterochromatic segments of chromosomes #1, #9, and #16 were analyzed in 38 children with malignant disease and 42 healthy persons. The analysis was carried out on C-banded metaphases obtained by peripheral blood culture. Using a quantitative method of analysis, an association was established between C-segment length of chromosome #9 and malignant disease in children. A disturbed quantitative relation of C-heterochromatin of chromosomes #1, #9, and #16 was also found in the group of children with malignant disease.

Marker chromosome 1q+ in acute lymphocytic leukemia☆

This paper presents the results of a cytogenetic analysis on a patient with acute lymphocytic leukemia (ALL) type L2 according to the FAB classification. Of the metaphases examined, 69.3% belong to the aberrant clone of pseudodiploid karyotype. Marker chromosome 14q+ has been identified in all the cells of the clone. Duplication was found in 30% of the metaphases, and in 15% triplication of the proximal segment of the long arm of chromosome #1 (q11-q21). In one metaphase the long arm of chromosome #1 is made up of segment q11-q21 four times repeated. Aberrations of chromosome #1 support the idea that heterochromatic region may be related to the higher degree of the cell malignity.

Heterochromatic variability in children with acute lymphoblastic leukemia

An analysis of the C-segment variability of chromosomes 1, 9, and 16 was carried out in 38 children with ALL, and 90 control subjects. When studying location variants, no differences were found between group of patients and the normal controls. A larger quantity of structural heterochromatin was, however, observed on chromosomes 1, 9, and 16, and a higher frequency of homologous chromosomes heteromorphism in children with ALL when compared with the control group.

Premature chromosome condensation in children with acute lymphocytic leukemia (L1) and malignant histiocytosis

In this study we report the observation of premature chromosome condensation (PCC) in two children with acute lymphocytic leukemia L1 and one child with malignant histiocytosis. Cytogenetic analysis was performed on peripheral blood or bone marrow cells cultivated for 24 hours without mitogen. In all three reported cases the modal karyotype was normal, while 12.9%, 5.5%, and 5% of spreads with PCC was observed, respectively.

Direct cytogenetic analysis of primary neuroblastoma

In this paper the results of cytogenetic analysis of a metastatic neuroblastoma from a 14-month-old boy are described. Direct cytogenetic analysis was performed on tumor pieces obtained from surgery prior to therapy. Consistent numerical and structural chromosome aberrations were identified. The modal chromosome number was 48, with 9.4% of the cell population being in the near-tetraploid range. In all karyotyped cells, the Y chromosome was missing and additions of chromosomes 7 and 14 were identified. Two rearranged #1 were observed: del(1)(p22 or p31) and t(1;18)(p22 or p31;q11-12), resulting in monosomy of the distal segment of the short arm and trisomy of the long arm. In two cells, single minutes were found; this chromosomal aberration has been previously described in a case of metastatic neuroblastoma.

Heterochromatic segment length of Y chromosome in 55 boys with malignant diseases

By investigating heterochromatic segment variability in a group of boys with malignant disease a significantly greater value of the Yc:F index in relation to the control subjects was established.

Embryonal rhabdomyosarocoma with 92,XXYY, +dmin and evidence of spontaneous cell fusion

The results of a cytogenetic analysis in an embryonal rhabdomyosarcoma are presented. A tetraploid karyotype with double minute chromosomes (dmin) was identified using a direct method of tumor tissue treatment. In 5% of the examined cells, evidence of spontaneous cell fusion was observed.