1/4. Isochromosome 1q as an early genetic event in a child with intracranial ependymoma characterized by molecular cytogenetics.Data concerning cytogenetic features of childhood ependymoma are rare. In this article, a gain of 1q was identified as the sole alteration in a primary childhood infratentorial ependymoma by comparative genomic hybridization (CGH). A recurrence of this brain tumor was studied using multiplex-fluorescence in situ hybridization (M-FISH) in addition to CGH and G-banding analysis. In accordance with the primary tumor, a gain of 1q corresponding to an isochromosome 1q was observed indicating an early event in the tumor development. Furthermore, M-FISH classified several other rearranged chromosomes including 6q and 17p that have previously been found to be involved in the development and progression of childhood ependymoma.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/4. Loss of chromosome 1 in myxopapillary ependymoma suggests a region out of chromosome 22 as critical for tumour biology: a FISH analysis of four cases on touch imprint smears.OBJECTIVE: Ependymomas are glial tumours. They constitute approximately 5-10% of intracranial tumours and are tumours which can recur. Predictive factors of outcome in ependymomas are not well established. Karyotypic studies are relatively scarce and loss of chromosome 22 has been described to correlate with recurrence. We are unaware of any reports involving chromosome 1 aberrations in the malignant progression of ependymomas. methods: cytogenetic analysis of four myxopapillary ependymomas was performed using double target fluorescent in situ hybridization (FISH), focusing on chromosomes 1 and 22. RESULTS: One patient's tumour had recurred. FISH was performed on 500 nuclei/tumours. All four cases showed a loss of chromosome 22q while only one showed an additional loss of chromosome 1p, and this was the one that recurred. CONCLUSIONS: We support the presence of a tumour suppressor gene on 1p associated with relapse in myxopapillary ependymomas and suggest that status of chromosome 1p by FISH may indicate a high-risk group of patients harbouring this tumour. More studies of this type are needed towards this direction as our results refer to a minimal number of individuals analysed.- - - - - - - - - - ranking = 0.5keywords = hybridization (Clic here for more details about this article) |
3/4. Recurrent anaplastic ependymoma with an abnormal karyotype and c-myc proto-oncogene overexpression.cytogenetic analysis on a supratentorial, recurrent, anaplastic ependymoma from a 29-year-old female disclosed the presence of an abnormal clone with the karyotype 46,XX,der(8)t(8;11)(q24;p11),-11,add(?)t(?;11)(?;q13). By the Northern hybridization assay and immunohistochemical staining, tumor cells revealed overexpression of c-myc proto-oncogene, although no evidence of amplification or structural rearrangement of this gene was found.- - - - - - - - - - ranking = 0.5keywords = hybridization (Clic here for more details about this article) |
4/4. Constitutional de novo t(1;22)(p22;q11.2) and ependymoma.There is a body of evidence suggesting the presence of a tumor suppressor gene on chromosome 22 which plays a role in the pathogenesis of ependymomas. We report a patient with a de novo constitutional t(1;22)(p22;q11.2) who developed a malignant ependymoma at age 5. The patient is otherwise phenotypically normal. By fluorescence in situ hybridization (FISH) analysis, the chromosome 22 breakpoint has been localized to the region between the DiGeorge locus and BCR. Since NF2 and EWS are both distal to BCR, the are presumable not involved in this rearrangement. This patient may offer a unique opportunity to identify the chromosome 22 ependymoma tumor suppressor gene by cloning the translocation breakpoint.- - - - - - - - - - ranking = 0.5keywords = hybridization (Clic here for more details about this article) |