Chromosome 9 aberrations by fluorescence in situ hybridisation in bladder transitional cell carcinoma.

To investigate the role of the monosomy 9 in bladder carcinogenesis, 96 cases of superficial bladder transitional cell carcinoma (TCC) were studied and followed periodically for around 3 years (mean+/-standard error of the mean (SEM); 3.46+/-0.34 years). Samples from bladder washings were analysed by fluorescent in situ hybridisation (FISH) to detect numerical anomalies of chromosome 9. Moreover, to evaluate the relative under representation of this chromosome, we detected numerical changes of chromosome 8 and DNA ploidy by flow cytometric analysis (FCM). Chromosome 8 copy number were related to FCM DNA ploidy and both were related with tumour grade. Monosomy 9 did not correlate with tumour grade, stage, chromosome 8 aneuploidies and abnormal DNA content, but correlated with tumour progression. Comparing the results in the primary and subsequent tumours, we observed an increase in the frequency of aneuploidies by FCM, associated with an increase of chromosome 8 polysomies. The mean chromosome 9 copy number/nucleus remained nearly the same in most of the primary and invasive tumours. Our results confirm that monosomy 9 is an early event and that it is retained during tumour progression and invasion and that the loss occurs before the tetraploidisation process. The relationship between the presence of a sub-population with monosomy 9 and tumour progression suggests the presence of a region that could have a role in the progression of superficial bladder TCC.

Health status and internal radiocontamination assessment in children exposed to the fallout of the Chernobyl accident.

The Chernobyl fallout caused release of radioisotope contaminants in a very large area that includes Belarus, the Ukraine, and the Russian Federation. In this study, the authors monitored the health status and level of internal contamination in 422 children who resided in the aforementioned areas and who were < or = 10 y of age at the time of the accident. The children came to Italy for a 1-mo period between 1991 and 1992. During this time, the children underwent pediatric checkups and biochemical, immunological, and thyroid analyses. All children underwent whole-body counter measurements, and urine radiotoxicological analysis was performed for 224 of them. The 24 children evacuated from Pripiat, a village very close to the Chernobyl reactor site, were selected for cytogenetic analysis. All of these children continue to have a detectable internal contamination of caesium radioisotopes. This condition is likely the result of ground and foodstuff contamination in the various areas. The children did not evidence overt pathologies related to ionizing radiation. However, minor alterations in immunological and thyroid parameters were observed in the group of the evacuated children. Traditional cytogenetic dosimetry was not possible, but the occurrence of acentric fragments was observed-indicating a persistent effect of continuous exposure to low doses of radiation.

Bladder transitional cell carcinomas: a comparative study of washing and tumor bioptic samples by DNA flow cytometry and FISH analyses.

OBJECTIVE AND METHODS: We compared information obtained from samples of tumor biopsy and bladder washing to evaluate the representatives of the latter type of sampling. Both types of samples from 44 cases of superficial bladder TCCs and one papilloma were analyzed by FCM, to evaluate cellular DNA content, and FISH, to detect numerical aberration of chromosome 9. RESULTS: The use of both tumor and washing samples by FCM and FISH analyses evidenced alterations in 95% of cases. FCM evidenced higher aneuploid frequency in bladder washing than in bioptic specimens. In bladder washing, FISH analysis showed higher frequency of monosomy and lower frequency of trisomy than in biopsy. No correlation was found between histological grade and centromeric chromosome 9 loss while correlation was evidenced with centromeric 9 gain. CONCLUSION: Irrigation specimens, analyzed by FCM and FISH, can complement information obtained by biopsy in cytodiagnosis and follow-up of patients with bladder TCC.

Children exposed to chronic contamination after the Chernobyl accident: cytogenetic and radiotoxicological analyses.

In this study, we describe cytogenetic studies of lymphocytes obtained from children who were exposed after the Chernobyl accident to low doses of ionizing radiation. We sought to determine possible chromosomal damage relative to internal contamination, as measured by whole-body counter and urine radiotoxicological analyses. The study was performed during a 1-mo period on the peripheral blood of children hosted in Italy, but who resided in contaminated regions of the Russian Federation and Belarus. We used conventional cytogenetics to detect chromosomal aberrations. In some cases, we also used "chromosome painting" to look for stable aberrations. There were more acentric fragments in subjects than in controls; a few chromosome and chromatid breaks werefound in the subjects, but this finding did not differ significantly between subjects and controls.

Cytometric DNA ploidy after different types of urinary diversions.

Patients undergoing uterosigmoidostomy (USS) have a high risk of developing colon cancer, while no evidence of an increased risk associated with rectal bladder (RB) has been reported. The purpose of the present study was to monitor the presence of aneuploidy by flow cytometry in patients who have undergone USS and RB as a possible basis for the identification of patients with an increased risk of malignant tumor occurrence. We have observed that 31% Of USS and 27% of RB cases were aneuploid. Data from the present investigation confirm that follow up studies may be useful in patients after urinary diversion.

Fluorescent in situ hybridization assessment of chromosome copy number in gestational trophoblastic disease.

The concurrence of congenital trisomy 8 mosaicism and gestational trophoblastic disease in a forty-two-year-old Gravida IV, Para IV female has been described. In contrast to other cases in the literature, this patient had no additional confounding chromosomal abnormalities other than trisomy 8. To the best of our knowledge, this was the only reported case of constitutional trisomy 8 mosaicism associated with gestational trophoblastic disease, a rare gynecological disease entity in and by itself. The present report describes fluorescent in situ hybridization (FISH) studies for assessing chromosome 8 copy number on various patient tissues. The results of the FISH studies are compared with each other and with the original cytogenetic studies. It is concluded that the overall frequency of trisomy 8 cells is lower in the FISH studies using archival material than in the original conventional cytogenetic studies. This is true for the uterus and lung tissues with a metastatic tumor. The possible reasons for the somewhat different frequencies found between conventional cytogenetics via GTG-banding and interphase cytogenetics via FISH are discussed.

Effects of 50 Hz magnetic fields on mouse spermatogenesis monitored by flow cytometric analysis.

Flow cytometry (FCM) was performed to monitor the cellular effects of extremely-low-frequency magnetic field on mouse spermatogenesis. Groups of five male hybrid F1 mice aged 8-10 weeks were exposed to 50 Hz magnetic field. The strength of the magnetic field was 1.7 mT. Exposure times of 2 and 4 h were chosen. FCM measurements were performed 7, 14, 21, 28, 35, and 42 days after treatment. For each experimental point, a sham-treated group was used as a control. The possible effects were studied by analyzing the DNA content distribution of the different cell types involved in spermatogenesis and using the elongated spermatids as the reference population. The relative frequencies of the various testicular cell types were calculated using specific software. In groups exposed for 2 h, no effects were observed. In groups exposed for 4 h, a statistically significant (P < 0.001) decrease in elongated spermatids was observed at 28 days after treatment. This change suggests a possible cytotoxic and/or cytostatic effect on differentiating spermatogonia. However, further studies are being carried out to investigate the effects of longer exposure times.

Interphase cytogenetics and flow cytometry analyses of renal tumours.

Fluorescent in situ hybridization (FISH) can be used to determine chromosome changes in human neoplasia. In our study, we have tested the feasibility of FISH to interphase cells of renal carcinoma to evaluate chromosome aneuploidies. We carried out in parallel in situ hybridization and flow cytometric studies in order to evaluate the possible correlation between numerical chromosome abnormalities and ploidies detected by flow cytometry (FCM). The ploidy of chromosomes 7, 11, 17 and 18 was investigated in three cases of this tumour utilizing specific probes. We found evaluable and comparable results in every case of renal carcinoma analyzed for both FISH and DNA FCM analyses and our results indicate that fluorescent in situ hybridization with chromosome-specific repetitive DNA probes can serve as a cytogenetic tool for the detection of numerical specific chromosome abnormalities of interphase nuclei of renal carcinoma.