Goike HM, Asplund AC, Pettersson EH, Liu L, Sanoudou D, Collins VP.
Acquired rearrangement of an amplified epidermal growth factor receptor (EGFR) gene in a human glioblastoma xenograft. J Neuropathol Exp NeurolJ Neuropathol Exp NeurolJ Neuropathol Exp Neurol. 1999;58:697-701.
AbstractAmplification of the epidermal growth factor receptor (EGFR) occurs in about 40% of human glioblastomas. In half of these cases, rearrangements of the amplified gene result in aberrant transcripts and proteins. The most frequent rearrangement affects the external domain of the receptor and results in nonbinding of ligand and constitutive activity. Less frequent rearrangements involve changes resulting in the loss of cytoplasmic amino acid sequences necessary for downregulation of the receptor following ligand binding. Here we report the development and selection for a rearranged amplified EGF receptor, which lacks cytoplasmic amino acid sequences in a human glioblastoma xenograft. An identical aberration has previously been reported in glioblastoma tissue. The patient tumor material, as well as the first passages of the xenograft showed amplification of the EGFR gene, but no evidence of gene rearrangement or an aberrant transcript. Interphase FISH data show the amplified gene on double minutes. Between passages 3 and 16, the growth rate of the xenograft almost doubled, the rearranged amplicon became dominant, as did the aberrant transcript, indicating selection under these conditions.
Ding X, Sanoudou D, Yang F, Chen H.
[Determination of trisomy 9p by molecular cytogenetic technology]. Zhonghua Yi Xue Yi Chuan Xue Za ZhiZhonghua Yi Xue Yi Chuan Xue Za ZhiZhonghua Yi Xue Yi Chuan Xue Za Zhi. 1999;16:383-5.
AbstractOBJECTIVE: To use molecular cytogenetic techniques for the determination of complex chromosomal aberrations that could not be distinguished by conventional cytogenetic method. METHODS: Chromosome painting, comparative genomic hybridization (CGH) and color banding chromosome analysis (RxFISH) were used to identify a case with chromosome 9 aberration by G-banding. RESULTS: The patient has a karyotype of 46,XX,9p+ by G-banding. Both chromosomes 9 were uniformly painted, including the extra segment on one of the 9p alleles. CGH revealed a duplication of the entire 9p short arm. After analysis with RxFISH the patient's karyotype could be accurately described as 46,XX,dup9p (p11-->p24::p24-->qter). CONCLUSION: The present report shows that some late technological developments in the field of cytogenetics can facilitate the study of the diseases linked to complex chromosomal aberrations and may find significant application in basic and clinical medical studies.
