Low incidence of SV40-like sequences in ependymal tumours.

Between 1955 and 1963, millions of children and adults were exposed to SV40-contaminated poliovirus vaccines. The oncogenic potential of this polyomavirus was revealed when intracerebral inoculation of SV40 into newborn hamsters resulted in the development of ependymomas and choroid plexus papillomas. Subsequently, SV40-like sequences were repeatedly detected in human ependymomas with broadly ranging incidence rates of 7-90%. Most epidemiological studies, however, have not described an increased occurrence of ependymomas. To gain more data on this controversial issue, this study examined 62 archived ependymal tumours from 31 children and 31 adults who underwent surgery between 1990 and 1999. Only three (5%) of the tumours--including 24 classical, 20 anaplastic, and 12 myxopapillary ependymomas; one subependymoma; and five ependymoblastomas--revealed subgenomic SV40 sequences. None of the ependymomas in patients born between 1920 and 1960 demonstrated SV40-like sequences. The positive tumours represent 7% of grade II and III ependymomas (two paediatric and one adult tumour). DNA sequencing of the PCR product revealed identical sequences of SV40 in the positive ependymal tumours. Compared with the results from other countries, this incidence rate is relatively low. Therefore, it seems likely that significant differences between individual countries exist regarding the prevalence of SV40-positive ependymomas. These differences may reflect different degrees of exposure to SV40-contaminated polio vaccine.

Genome-wide analysis of sixteen chordomas by comparative genomic hybridization and cytogenetics of the first human chordoma cell line, U-CH1.

Cytogenetic information on chordomas is rudimentary and restricted to GTG-banding analysis of 26 cases worldwide. In this study, we present the chromosomal imbalances detected in a series of 16 chordomas (10 sacrococcyeal, five sphenooccipital, and one spinal) from 13 patients using comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH). On average, 3.2 losses and 4.2 gains were detected per tumor. The most common DNA copy number alterations were losses on chromosomal arms 3p (50%) and 1p (44%). Losses of 3p were detected in five of seven primary chordomas. Therefore, the loss of 3p might be an early event in chordoma genesis. The most common gains involved 7q (69%), 20 (50%), 5q (38%), and 12q (38%). Additionally, we raised the first human chordoma cell line, U-CH1, from a recurrence of a sacral chordoma. U-CH1 and its parent tumor had almost the same CGH profile. According to GTG-banding and multicolor FISH, U-CH1 has the following clonal chromosomal abnormalities: der(1)t(1;22), del(4), +del(5), +del(6), +7, del(9), del(10), +der(20)t(10;20), +21. Thus, the novel permanent human chordoma cell line U-CH1 has chordoma-typical cytogenetic aberrations. Our data suggest that tumor suppressor genes or mismatch repair genes (located at 1p31 and 3p14) and oncogenes (located in 7q36) might be involved in chordoma genesis.

Fatal outcome in a patient developing Epstein-Barr virus-associated lymphoproliferative disorder (EBV-LPD) without measurable disease.

A 51-year-old female patient in the first chronic phase of CML received an allogeneic PBSCT from a matched unrelated donor. The transplant was manipulated by CD34+ cell selection. On day +193 after transplantation the patient was readmitted to the hospital with recurrent fever of unknown origin and cough. Clinical, radiographic and sonographic evaluation revealed no characteristic findings besides a mild splenomegaly. Screening for EBV, CMV, RSV and HSV did not indicate an active infection. On day +203 the patient developed generalized seizures, respiratory failure and died within 24 h in multiorgan failure. The macroscopic postmortem was still not enlightening; the histological examination however, demonstrated diffuse organ infiltration by monoclonal lymphoblastoid cells due to EBV-LPD.

Low frequency of chromosomal imbalances in anaplastic ependymomas as detected by comparative genomic hybridization.

We screened 26 ependymomas in 22 patients (7 WHO grade I, myxopapillary, myE; 6 WHO grade II, E; 13 WHO grade III, anaplastic, aE) using comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH). 25 out of 26 tumors showed chromosomal imbalances on CGH analysis. The chromosomal region most frequently affected by losses of genomic material clustered on 13q (9/26). 6/7 myE showed a loss on 13q14-q31. Other chromosomes affected by genomic losses were 6q (5/26), 4q (5/26), 10 (5/26), and 2q (4/26). The most consistent chromosomal abnormality in ependymomas so far reported, is monosomy 22 or structural abnormality 22q, identified in approximately one third of Giemsa-banded cases with abnormal karyotypes. Using FISH, loss or monosomy 22q was detected in small subpopulations of tumor cells in 36% of cases. The most frequent gains involved chromosome arms 17 (8/26), 9q (7/26), 20q (7/26), and 22q (6/26). Gains on 1q were found exclusively in pediatric ependymomas (5/10). Using FISH, MYCN proto-oncogene DNA amplifications mapped to 2p23-p24 were found in 2 spinal ependymomas of adults. On average, myE demonstrated 9.14, E 5.33, and aE 1.77 gains and/or losses on different chromosomes per tumor using CGH. Thus, and quite paradoxically, in ependymomas, a high frequency of imbalanced chromosomal regions as revealed by CGH does not indicate a high WHO grade of the tumor but is more frequent in grade I tumors.

Demonstration of p53 protein and TP53 gene mutations in oligodendrogliomas.

Paraffin embedded tissue of 84 oligodendrogliomas (63 primary tumours, 21 recurrences), 21 glioblastomas with oligodendroglial growth pattern (15 primaries, 6 recurrences) and 17 mixed gliomas was investigated for the presence of mutations in exons 5-9 by means of single stranded conformation polymorphism (SCCP), temperature gradient gel electrophoresis (TGGE) and direct DNA sequencing. In parallel, p53 protein accumulation was determined by means of immunohistochemistry. The percentage of mutations was found to be higher than previously reported (6 of 44 grade II oligodendrogliomas, 4 of 19 grade III oligodendrogliomas, 4 of 15 glioblastomas). In 4 cases, the mutations lead to distinct changes in the primary or secondary structure of the protein (cysteine-->tyrosine, proline-->leucine) and were associated with marked accumulation of p53 protein. A significant correlation between p53 protein accumulation and TP53 gene aberrations was found (P < 0.001), although p53 protein accumulation was detected more often than TP53 gene anomalies, indicating that factors other than TP53 gene mutation may also lead to a p53 protein accumulation in the tumour cells. A significant correlation was found for p53 protein accumulation and tumour grade but not TP53 gene mutations. In conclusion, evaluation of p53 protein accumulation reflected the clinical course of oligodendrogliomas better than the mere presence of TP53 gene mutations.

An object-oriented software for fate and exposure assessments.

The model system CemoS(1) (Chemical Exposure Model System) was developed for the exposure prediction of hazardous chemicals released to the environment. Eight different models were implemented involving chemicals fate simulation in air, water, soil and plants after continuous or single emissions from point and diffuse sources. Scenario studies are supported by a substance and an environmental data base. All input data are checked on their plausibility. Substance and environmental process estimation functions facilitate generic model calculations. CemoS is implemented in a modular structure using object-oriented programming.

Interleukin-1 beta and interferon gamma interact with fibroblast growth factor-2 in the control of neuroblastoma cell proliferation and differentiation.

Based on our previous observations that neuroblastoma (NB) cells express fibroblast growth factor-2 (FGF-2; basic FGF) and respond to it [Janet T. et al. (submitted); Wewetzer K. et al. (1993) J. Neurosci. Res. 36, 209-215), we attempted to find to what extent selected cytokines [interleukin (IL)-1 beta and interferon gamma (IFN gamma)] may modulate FGF-mediated proliferative activity and differentiation. The NB cell lines IMR-32, SH-SY5Y, GIMEN and LAN-1 and colorimetric assays were used for the determination of cell numbers. IL-1 beta (and several other ILs, including IL-1 alpha, -2, -3, and 6) per se did not affect proliferation of any cell line studied. IFN gamma inhibited growth of GIMEN and LAN-1 cells, but was uneffective on IMR-32 and SH-SY5Y cells. FGF-2 was antimitogenic for GIMEN cells. IFN gamma reversed and IL-1 beta enhanced this antimitogenic effect of FGF-2. FGF-2 per se did not affect LAN-1 cells and did not modulate the growth inhibitory actions of IFN gamma on these cells. FGF-2 induced proliferation of IMR-32 and SH-SY5Y cells. This effect was not modulated by IFN gamma or IL-1 beta. These results suggest a heterogeneous response pattern of human NB cell lines towards the cytokines studied and complex interactions of FGF-2, IL-1 beta and IFN gamma.