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Background/aims: Non-alcoholic fatty liver disease (NAFLD) and cryptogenic cirrhosis (CC), which is largely a late sequela of NAFLD, are considered pre-neoplastic conditions that might progress to hepatocellular carcinoma. Aneuploidy, telomere aggregates and synchronization of replication were evaluated as markers of genetic instability in these patients., Methodology: Peripheral blood lymphocytes from 22 patients with NAFLD, 20 patients with CC and 20 age-matched healthy controls were analyzed. To determine random aneuploidy, we used the fluorescence in situ hybridization (FISH) with probes for chromosomes 9 and 18. The rate of aneuploidy was inferred from the fraction of cells revealing one, three or more hybridization signals per cell. Aggregate size was divided into three fusion groups of 2-5, 6-10 and 11-15 telomeres, relative to the size of a single telomere. The replication pattern was determined by FISH in two pairs of alleles, 15qter and 13qter. Asynchrony was determined by the presence of one single and one set of double dots in the same cell., Results: Significantly higher random aneuploidy rate was found in the CC patients than in the control group, and to a lesser degree in NAFLD patients. Telomere aggregates were insignificantly higher in both groups. Only patients with CC showed significantly higher rate of asynchronous replication with proportionately more cells with two single dots among the normal cells (p<0.001)., Conclusions: These results likely reflect changes in gene replication and cell cycle progression in these conditions, possibly correlating with their malignant potential., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Objective: Individuals with chromosomal aneuploidies tend to develop malignancies. Telomerase is an enzyme complex that lengthens telomeres and has enhanced expression in numerous malignancies; one of its components is encoded by the TERC gene. In this study, we evaluated the TERC gene copy number in amniocytes from fetuses with aneuploidy, other than trisomy-21., Methods: In this prospective, basic research study, fluorescence in situ hybridization (FISH) for the TERC gene (3q26) was applied to amniocytes retrieved from 14 fetuses with various aneuploidies and from a control group of 6 fetuses with a normal karyotype, to determine the TERC gene copy number., Results: The percentage of cells with more than two copies of the TERC gene was lowest in the control group (x3=1.2 ± 0.4%; x4=0 ± 0%), higher in the sex chromosome aneuploidies (x3=4 ± 3%; x4=0.7 ± 0.95%) and even higher in trisomy 18 (x3=10.6 ± 2.3; x4=4.6 ± 1.8). The differences were statistically significant (P<0.05)., Conclusion: The TERC gene copy number is increased in aneuploid amniocytes, which demonstrates their genetic instability and is presumably related to their tendency to develop malignancies., (Copyright © 2012. Published by Elsevier B.V.)

Hepatitis C virus (HCV) has been recently recognized as a potential cause of B-cell lymphoma. Both chronic hepatitis B and C with or without cirrhosis represent major preneoplastic conditions, and the majority of hepatocellular carcinomas arise in these pathological settings. According to the aneuploidy-cancer theory, carcinogenesis is initiated by random aneuploidy, which is either induced by carcinogens or arises spontaneously. The aim of this study was to evaluate random aneuploidy rate in HCV patients during chronic infection and remission (past infection eradicated), compared with non-Hodgkin lymphoma (NHL) patients and healthy controls. To determine random aneuploidy, we applied the FISH technique with probes for chromosomes 9 and 18. Significantly higher random aneuploidy rate was found in the HCV-infected and lymphoma patients than in the control group; the past HCV group in remission had intermediate rates, between those of the control group and the chronically infected patients. Patients who have eradicated HCV infection may nonetheless carry higher risk for future malignancy and therefore need long-term follow-up.

Unlabelled: The cause of aneuploidy in fetuses of young women is not fully understood. As such women are considered to be at risk of repeating the "error", it is customary to recommend chromosomal evaluation (karyotyping) in subsequent pregnancies. Individuals predisposed to meiotic nondisjunction exhibit aneuploidy in their mitotic cells (mosaicism). The aim of this study was to assess the actual risk for repeated aneuploidy in patients who had a previous pregnancy with aneuploidy by estimating the rate of somatic random aneuploidy in their normal pregnancy and to assess whether this risk is heritable. With utilization of FISH, we assessed the number of chromosomes 9 and 18 in amniocytes from the following pregnancies: 1. Fourteen of the women had a history of chromosomal aneuploidy in a previous pregnancy (study group). 2. Ten women had previous normal pregnancies (control). 3. Nine samples were assessed in amniocytes taken from aneuploid pregnancies (positive controls). A mean of 458+/-65.66 amniocytes were evaluated (range 97-500 nuclei). There was no significant difference in the rate of aneuploidy of both chromosomes between the study and control groups. However, this rate was significantly higher in the aneuploid pregnancies (p < 0.05)., Conclusion: The known tendency for repeated nondisjunction shown in women with previous aneuploid babies could not be demonstrated in their offsprings.

Objective: In this study, we applied the fluorescent in situ hybridization (FISH) technique and compared the common numerical abnormalities with chromosomes 13, 16, 18, 21, X, and Y in spontaneous to artificial abortion. This would cover about 75% of the common aneuploidy in spontaneous abortion., Methods: Placentas were taken from 59 patients with a first trimester spontaneous abortion and 61 patients who underwent an elective first trimester pregnancy termination. The range of growth was from 5 to 12 gestational weeks. Placentas were processed according to direct chorionic villi preparation. Direct dual color FISH was performed according to Vysis protocol with the probes for the following chromosomes: 13, 16, 18, 21, X, and Y., Results: The aneuploidy rate in spontaneous abortion was 55.9% and in artificial abortion 8.2%. There was a significant difference between the two groups in the aneuploidy rate (P = 6 x 10(-9))., Conclusion: FISH is a rapid, efficient, and relatively inexpensive tool in detecting aneuploidy in placentas from cases of spontaneous abortions. Our rate of detected aneuploidy is compatible with other reports in which conventional cytogenetics was utilized.

Objective: Because the effect of granulocyte colony-stimulating factor (G-CSF), which is widely used for allogeneic stem cell transplantation, on DNA function and stability has not yet been unequivocally elucidated, the aim of this study was to determine whether G-CSF leads to epigenetic and/or genetic modifications., Materials and Methods: Molecular cytogenetic techniques based on fluorescence in situ hybridization technology were used., Results: Lymphocytes of G-CSF mobilized donors displayed epigenetic (altered replication timing of alleles) and genetic (aneuploidy) alterations similar to those observed in lymphocytes of cancer patients. Specifically, in the donors' lymphocytes, biallelically expressed genes (TP53 and AML1) and a repetitive noncoding DNA sequence associated with chromosome segregation (CEN17) showed loss of synchrony in allelic replication timing (allele-specific replication). Each displayed a highly asynchronous pattern of allelic replication similar to that characterizing monoallelic expressed genes. This non-locus-specific epigenetic phenomenon, which also affects DNA sequences associated with chromosome segregation, was accompanied by aneuploidy. Although the loss of replication synchrony in the lymphocytes of G-CSF mobilized donors was a transient epigenetic modification, aneuploidy remained unchanged. The G-CSF effect also was observed after G-CSF administration in vitro. 5-Azacytidine, a DNA methylation blocking agent, inhibited G-CSF in vitro induction of allele-specific replication., Conclusion: G-CSF, probably via changes in DNA methylation capacity, leads to cancer-characteristic DNA modifications in lymphocytes of normal mobilized donors.

We hypothesize that coordination between the two DNA parental sets in somatic cells is essential for the stability of the diploid genome, and that its disruption is associated with the many alterations observed in the various cancerous phenotypes. As coordination between two allelic counterparts is well exemplified by synchrony in replication timing, we examined, in blood cells of patients suffering from various hematologic malignancies, replication patterns of five loci. These loci were three cancer-implicated genes (TP53, AML1, and RB1) and two nontranscribed sequences engaged in chromosome segregation. All five loci normally display synchrony in allelic replication timing. In addition, in order to exemplify an asynchronous mode of allelic replication, we followed the replication of allelic counterparts of an imprinted gene (SNRPN), which is distinguished by its asynchronous mode of allelic replication (allele-specific replication). Allelic replication patterns were studied by fluorescence in situ hybridization (FISH), which has been shown to distinguish between nonreplicated and replicated regions of the genome in interphase cells, based on the structure of the specific hybridization signals that are being detected. Using the FISH replication assay we observed, for all loci which normally exhibit synchrony in allelic replication, loss of synchrony when present in blood cells of patients with hematologic malignancies. The loss of synchrony in allelic replication in patients' cells was accompanied by aneuploidy (chromosome losses and gains), the hallmark of cancer. We were able to reinstate the normal pattern of replication in the patients' cells by introducing an inhibitor of DNA methylation. It thus appears loss of allelic coordination is an epigenetic alteration characterizing cancer, which is easily identified by simple cytogenetic means and has a potential use in both cancer investigation and detection.

We assessed possible inter- and intraindividual variations in the frequency of disomy in sperm cells from three men with abnormal sperm analysis parameters. Mono- and dual-color fluorescence in situ hybridization (FISH) was applied to sperm cells from different samples of the men. Four men with a normal sperm profile were used as controls. The samples were taken separately over a period of 6 months. FISH probes used for the disomy rate analysis were clones from the satellite region of chromosomes 8, 18, X, and Y. The study group showed a significantly higher disomy rate compared with the control group, whereas there was no significant difference in the disomy rate between three different samples from the same individuals. These results suggest that the sampling time has no importance in assessing the rate of nondisjunction in sperm cells.

Telomeres are TTAGGG repetitions at the ends of chromosomes. Functioning telomeres are essential for normal segregation and maintenance of chromosomes during mitotic and meiotic divisions. Dysfunctional telomeres support the survival of aneuploid cells, a characteristic of many human malignancies. In contrast to the non-overlapping nature of telomeres in normal nuclei, telomeres of tumor nuclei tend to form aggregates. In this study, our objective was to evaluate the number of telomere aggregates (TAs) in karyotype-balanced structural rearrangements. This is an additional parameter of genetic instability, which might suggest a possible increased risk for diseases related to genomic instability, such as cancer. Twenty-six amniotic fluid cell cultures were established following genetic amniocentesis. Telomere FISH protocol was applied to the samples. Telomere aggregates were counted using a 2D microscope. The results were statistically tested by analysis of variance (ANOVA) and Kruskal-Wallis tests. More telomere aggregates in the structural balanced rearrangements were found in both study groups (balanced translocations and inversions) compared to the control group (P < 0.05). The persistence of TAs in cells is probably related to Breakage-Bridge-Fusion (BBF) cycles, a mechanism of TAs described by Muller and McClintock, resulting in end-to-end fusion that contributes to the onset of genomic instability. BBF cycles contribute to deletions, gene amplification, non-reciprocal translocations, and overall genetic changes associated with tumor genesis. According to our studies, the individuals who are carriers of balanced structural chromosomal rearrangements show some of the genetic instability parameters that appear in other circumstances, such as premalignant and malignant conditions. [ABSTRACT FROM AUTHOR]

Objectives Genomic aneuploidy is a common cause of human genetic disorders. Individuals with aneuploidy tend to develop malignancies. Recent studies correlated aneuploidy with early aging, senescence and organ dysfunction. This study investigated potential explanations for these increased risks by evaluating random aneuploidy and senescence rates in amniocytes from fetuses with aneuploidy. Methods The rates of random aneuploidy in amniocytes from normal pregnancies were evaluated and compared to amniocytes from fetuses with trisomies 21, 18 and 47,XXY using a FISH technique with X + Y, 9 and 18 probes. Senescence was evaluated by calculating the percentage of amniocytes with fragmented nuclei: senescence associated heterochromatin foci (SAHF), using DAPI staining. Results Significantly increased rates of cells with aneuploidy were observed in trisomies 18 and 21, and 47,XXY (p < 0.001) compared to the control group for the somatic and sex chromosomes. Increased rates of amniocytes with SAHFs were observed among the trisomy samples compared to the control group. Conclusions Higher incidence of random aneuploidy and senescence were observed in amniocytes from fetuses with trisomy. These findings might explain the greater lifetime tendency to develop malignancies and diseases related to early aging in these individuals. [ABSTRACT FROM AUTHOR]

Abstract: Background: Fetal cells exfoliate in the uterine cavity during early pregnancy and are a potential source of material for NIPD. Aims: This study was designed to test the hypothesis that fetal cells obtained from the uterine cervix during the first trimester of pregnancy could be utilized for prenatal diagnosis of chromosomal aneuploidy. Study design: Fetal cells retrieved from the distal endocervical canal during the first trimester of pregnancy were hybridized with chromosome 21 specific FISH probes and analyzed with an automated fluorescence microscope. Subjects and outcome measures: Cells with 3 copies of chromosome 21 were detected in 5 out of 5 trisomy 21 pregnancies. Results: The number of trisomic cells detected ranged from 1 to 27 with a median value of 5. Conclusions: FISH-based scanning can identify trisomy 21 pregnancies by analysis of routine cervical brushings. The approach offers the potential for non-invasive prenatal diagnosis as early as 5weeks gestation. [Copyright &y& Elsevier]