Beyhan Durak

Prognostic impact of chromosome alterations detected by FISH in Turkish patients with B-cell chronic lymphocytic leukemia

The goal of this study was to evaluate the relation of chromosomal abnormalities detected by fluorescence in situ hybridization (FISH) in the prognosis of B-cell chronic lymphocytic leukemia (B-CLL) patients. We evaluated the common recurrent chromosomal aberrations in 79 B-CLL patients (51 men, 28 women; mean age 64.3+/-1.2) by FISH analysis using 11q22.3 (ATM), 13q14.3 (13S319 and 13S25), CEP12, and 17p13.1 (TP53) specific probes. Of the 79 patients analyzed by FISH, 40 or 50.6% had at least one aberration. In particular, 34 (43%) patients had a single abnormality and 6 (7.6%) patients had 2 abnormalities. The most frequent abnormality was 13q14.3 deletion, which was detected in 26 (32.9%) patients. Trisomy 12 was seen in 12 (15.2%) cases, and was followed by 17p13.1 (TP53) deletions and 11q22.3 (ATM) deletions in 6 (7.6%) and 4 (5.1%) patients, respectively. When the overall frequencies of these chromosomal aberrations were distributed according to RAI stages, the majority of patients with 13q14.3 deletion (55%), trisomy 12 (70%), and ATM or TP53 deletions (66.7 %) were in advanced stages of disease (RAI II-IV). The overall survival durations in good, intermediate, and poor prognostic groups were 51+/-1.3, 50.9+/-8.6, and 12+/-3.3 months, respectively. Our data suggests that FISH analysis of B-CLL patients provides important diagnostic, clinical, and prognostic information which may help clinicians assess the prognosis and make appropriate treatment decisions.

A rare case: mosaic trisomy 22

A 9-year-old female child of healthy parents (mother: 43 years, father: 44 years) was referred to our center because of severe mental retardation. While pedigree analysis was not contributory, two older sibs were normal and healthy. Physical examination revealed facial dysmorphism, microcephaly and hyperflexibility of all joints. Her chromosome constitution showed a mosaic pattern; mos 46,XX[98]/47,XX,+22[2]. So skin biopsy was performed and mosaic trisomy 22 was confirmed with FISH analysis (46,XX[73]/47,XX,+22[27]). Physical features of this case seemed consistent with her mosaic constitution. This report would be a demonstrative example to show the significant contribution of FISH in states of mosaicism.

FISH analysis with locus-specific probes in sperm from two translocation carrier men

Meiotic segregation of normal and derivative chromosomes was analysed in sperm samples from two balanced reciprocal translocation carrier men by use of dual‐colour fluorescence in situ hybridisation (FISH) technique. The translocations were t(4;8)(p15;p12) and t(15;22)(q(23;q13.2), and the digoxigenin‐labelled FISH probes were specific to either the translocated or centric segments of the chromosomes involved in the translocations. A total of 1000 spermatozoa for each probe were analysed and the modes of segregation were described on the basis of signals in each sperm cell. The mean frequency of alternate and/or adjacent‐1 (adj‐1) segregation types was 69.47%, whereas they were 30.51 and 78.70% for the adjacent‐2 (adj‐2) and alternate/adj‐2 segregation types, respectively. This study illustrated that FISH is a valuable technique for analysing the meiotic segregation products of the heterozygotes in respect to aneuploidy risk.

Trisomy 7 in synovial fluid cells of patients with rheumatoid arthritis

ObjectiveRecent studies revealed trisomy 7 as a chromosomal abnormality in non-neoplastic disorders such as rheumatoid arthritis (RA). In the present study, we investigated the presence of trisomy 7 in the synovial fluid cells of patients with RA using fluorescence in situ hybridisation (FISH) analysis.MethodsSynovial fluid from 15 patients with RA was collected from knee joints. The control group consisted of seven patients with traumatic synovial effusion in their knee joints. The arthrocenteses were performed under aseptic conditions. Dual-colour FISH analysis was performed using chromosome-7-specific LSI D7S522 (7q31) and chromosome-5-specific LSI EGR1 (5q31)/D5S721 (5p15.2) probes on the slides prepared from synovial fluid of RA patients and controls.ResultsThe slides of our cases were analysed using two different DNA probes. When the slides hybridised with chromosome-5-specific probes were analysed, no trisomic or monosomic cells were revealed in both patients and controls. However, in eight of 15 patients, trisomy 7 occurred in variable percentages of cells (23% to 48%) of synovial fluid. No monosomic 7 cells were detected in these specimens. All control cases were disomic for chromosome 7.ConclusionThe results of the present investigation suggest that trisomy 7 may play a role in the pathogenesis of synovial hyperproliferation in RA.

Langerhans cell histiocytosis with transformation to acute leukemia showing 45,X, t(8; 21), 5q-, -Y karyotype

A 31-year-old man was admitted to hospital with onset of difficulty in walking and urinary incontinence, leading to the diagnosis of Langerhans cell histiocytosis (LCH) which was replacing a thoracic vertebra. Four months after the completion of radiation therapy, he was referred to our department with persistent fever and severe pyogenic ulceration mainly affecting the right-hip. A diagnosis of acute non-lymphoblastic leukemia (ANLL) was made. Cytogenetic studies showed 45, X, t (8; 21), 5 q -, - Y. We report this case because, development of acute leukemia after LCH is rare and the literature searched for any cytogenetic study in these kind of cases yielded no data.

A New Case of dic(1;15)(p11;p11) in AML M1: Apropos of a Case and a Review of the Literature

Acute myelogenous leukemia (AML) develops as the consequence of a series of genetic changes in a hematopoietic precursor cell. Specific cytogenetic abnormalities have been identified by karyotype analysis in AML. One of the rare chromosomal abnormalities is a dicentric chromosome, which is defined as an aberrant chromosome having two centromeres. In the literature, a limited number of cases have been reported with dic(1;15) in myeloid disorders, but only one case has been reported with in acute megakaryoblastic leukemia. Herein, we report a case of acute myelogenous leukemia without maturation with a dic(1;15)(p11;p11), resulting in trisomy of the long arm of chromosome 1. To date, this is the second case of dic(1;15) in acute myelogenous leukemia and the first case in acute myeloblastic leukemia without maturation.

Conventional and molecular cytogenetic analyses in Turkish patients with multiple myeloma.

Objective: Multiple myeloma (MM) is characterized by the accumulation and proliferation of malignant plasma cells, secreting monoclonal immunoglobulins and genetic abnormalities in MM have implications for disease progression and survival. In the present study, we investigated the frequency of chromosomal abnormalities (CA) in Turkish patients with MM, using interphase FISH and CC and evaluated the relationship between the rearrangements detected, prognosis and stage of disease. Material and Methods: We performed conventional cytogenetic and FISH studies in 50 patients to detect chromosome anomalies associated with MM. FISH probes were used to detect 13q14, 13q34, 17p13 deletions, IGH rearrangements, and monosomy and/or trisomy of chromosomes 5, 9, and 15. Results: CC studies could be performed in 32 of 50 cases and five patients (15.6%) showed chromosomal aberrations while 27 (84.3%) had normal karyotypes. By FISH, eighteen percent (9/50) of cases were found to be normal for all parameters evaluated. Eighty-two percent (41/50) of the patients were positive for at least one abnormality. Chromosome 13 anomalies were detected in 54% (27/50) of cases. The second most common aberration observed is chromosome 15 aberrations (50%). Conclusion: Median survival rate was shorter in patients with one of the abnormalities including chromosome 13 aberrations, IGH rearrangements or P53 deletions. Chromosome 15 aberrations were significantly higher in patients with stage III disease (p=0.02). We conclude that FISH studies should be performed in conjunction with conventional cytogenetic analysis for prognosis in multiple myeloma patients.

Rapid molecular cytogenetic diagnosis of transfusion associated graft-versus-host disease by fluorescent in situ hybridization (FISH)

Transfusion associated graft-versus-host disease (TA-GVHD) is a rare, dreadful complication of transfusion in immunocompromized and immunologically competent individuals. The diagnosis is often delayed, because of lack of awareness and the non-specific clinical features. We describe a rapid molecular cytogenetic analysis of FISH for the diagnosis of two cases of TA-GVHD with sex-mismatched donors. The use of FISH is a rapid and sensitive technique for the early diagnosis of TA-GVHD when the recipient and donor are of different gender.

Performance of MLPA as a screening method for aneuploidy in uncultured amniocytes.

OBJECTIVE To test whether the Multiplex Ligation-dependent Probe Amplification (MLPA) technique can be used as a screening test for rapid diagnosis of aneuploidies in uncultured amniocentesis. MATERIAL AND METHODS In this prospective blind study, MLPA with chromosomes 13,18,21,X and Y specific probe mixes was performed in 500 amniotic fluid samples. Chromosome copy numbers were determined by analyzing size and peak area for each MLPA probe. Results were compared with those of karyotyping/FISH. RESULTS Conclusive test results were obtained in 98% of the samples, whereas 10 were inconclusive. In all conclusive tests, the MLPA results were concordant with that of cytogenetic and/or FISH analyses. There were no false-positive results. A case with 69,XXX triploidy could not be diagnosed by MLPA. In total, 28 aneuploidies were diagnosed. There were no false-positive results. The performance of each probe was determined. CONCLUSION MLPA is a rapid, simple and reliable assay for aneuploidy screening in uncultured amniocytes.