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E Meese

Publications and source records attributed to E Meese.

At least 55 records · Page 3Linked to original sources
PubMed1996

Human endogenous retroviral element k10 (HERV-K10): chromosomal localization by somatic hybrid mapping and fluorescence in situ hybridization.

The human endogenous retrovirus K10 (HERV-K10) was mapped to human chromosomes using HERV-K10 specific PCR primers on a somatic hybrid mapping panel. A non-random chromosomal location was demonstrated with PCR signals on chromosomes 1, 3, 4, 5, 6, 7, 10, 11, 12, 14, 15, 19, 20, 21, 22 and Y. There was a lack of PCR products on the other chromosomes, even after hybridization with a HERV-K10 specific probe. To further localize the HERV-K10 sequence we used fluorescence in situ hybridization. Chromosomes 1, 3, 6, 7, 10, 11, 12 and 22 were found to contain several HERV-K10 sequences in different regions. The presence of several integration sites on some chromosomes is consistent with previous studies demonstrating 30-50 copies of the HERV-K10 sequence per haploid genome. The mapping information reported in this study will assist the analysis of the biological significance of the HERV-K10 sequence.

Base Sequence↗
PubMed1995

Amplification of the MET gene in glioma.

We have previously reported the finding of MET amplification linked to double minutes (dmins) in a human glioblastoma (TX3095). Because dmins are found in approximately 50% of glioblastomas, 18 gliomas were analyzed for MET amplification. Three grade IV glioblastomas and one grade II astrocytoma showed amplification. We could also localize the MET amplicon to dmins in glioblastoma TX3095 by fluorescence in situ hybridization.

Base Sequence↗
PubMed1995

Assignment of Alu-repetitive sequences to large restriction fragments from human chromosomes 6 and 22.

We have employed a pulsed field gel electrophoresis and Alu hybridization approach for identification of large restriction fragments on chromosome 6 and 22. This technique allows large portions of selected human chromosomes to be visualized as discrete hybridization signals. Somatic cell hybrid DNA which contains chromosome 6 or chromosome 22 was restricted with either Notl or Mlul. The restriction fragments were separated by pulsed field gel electrophoresis (PFGE) and hybridized against an Alu repetitive sequence (Blur 8). The hybridization signals result in a fingerprint-like pattern which is unique for each chromosome and each restriction enzyme. In addition, a continuous pattern of restriction fragments was demonstrated by gradually increasing puls times. This approach will also be suitable to analyze aberrant human chromosomes retained in somatic cell hybrids and can be used to analyze flow sorted human chromosomes. To this end, our method provides a valuable alternative to standard cytogenetic analysis.

Chromosome Mapping↗
PubMed1995

Generation and characterization of a human chromosome 6-specific hncDNA library from a somatic cell hybrid.

Chromosome specific cDNA libraries are a useful source of candidate genes for disorders which have been linked to particular chromosomes. Here, we report the generation of a cDNA library made from a somatic cell hybrid retaining chromosome 6 as its only human component. In order to ascertain the chromosomal location of cDNAs the library was amplified by inter-Alu-PCR and used as probe for competitive in situ suppression (CISS). To identify human specific cDNA clones the library was screened with PD39, a highly human specific Alu consensus probe. Out of 350,000 clones 360 were found to hybridize with PD39. Nucleotide sequences were determined for 40 clones with inserts larger than 500 basepairs (bp) and a sequence comparison was performed at the National Center for Biotechnology Information using BLASTN. One clone was shown to be identical to Manganese Superoxide Dismutase (MnSOD/SOD2) which has previously been assigned to chromosome 6q25. Localization of 11 clones was determined using PCR and clone-specific primer pairs on a hybrid mapping panel DNA set. Two PCR-localized clones and five additional clones were localized by fluorescence in situ hybridization. Transcripts for five clones were identified by RT-PCR. The generation of chromosome 6-specific hncDNAs from a somatic cell hybrid should aid in the identification of disease-associated genes localized on this chromosome.

Animals↗
PubMed1995

Isolation and localization of transcribed sequences on human chromosome 22.

Recently, we reported the generation of a heteronuclear (hn) cDNA library from a human x rodent somatic cell hybrid retaining human chromosome 22. Here, we report the characterization and localization of 12 cDNA derived clones from this library. Human-specific cDNA sequences have been selectively amplified by inter-Alu PCR. To exclude Alu transcripts, only clones with inserts larger than 500 bp were analyzed. Ten of the 12 clones were localized by PCR on chromosome 22, with four clones mapping on additional chromosomes. One PCR-localized clone and two additional clones were mapped on chromosome 22 by in situ hybridization. Transcripts in human cells were identified for seven of the eight clones analyzed by RT-PCR. None of the clones showed significant sequence similarities within the GenBank and EMBL databases, indicating that these clones represent previously unknown genes. This is the first report on the isolation of chromosome 22-specific transcripts from a human x rodent somatic cell hybrid.

Animals↗
PubMed1995

Lack of isodisomy for chromosome 22 in disomic meningiomas.

Loss of one copy of chromosome 22 is the most prevalent chromosomal change in meningioma, indicative of a tumor suppressor on chromosome 22. Meningioma retaining both copies of chromosome 22 could be possibly be explained by isodisomy for a meningioma suppressor gene. To investigate whether the chromosomal situation in meningioma is consistent with this hypothesis, we studied 53 cases, using polymorphic probes localized on chromosome 22. loss of one copy of chromosome 22 was found in 14 cases when polymorphic DNA markers were used. Thirty-nine meningiomas studied by karyotyping and molecular probes retained both copies of chromosome 22. The majority of cases (30/39, or 77%) displayed heterozygous banding patterns, indicating the presence of heterologous copies of chromosome 22. Hence, our data provide no evidence for duplication of one parental homolog as a general mechanism in diploid meningioma.

Chromosome Aberrations↗
PubMed1994

Coamplification on chromosomes 7p12-13 and 9q12-13 identified by reverse chromosome painting in a glioblastoma multiforme.

DNA amplification is known to occur in approximately 50% of glioblastomas, with the epidermal growth factor receptor (EGFR) gene being the most frequently amplified. Whereas previous amplification studies have largely been limited to the analysis of known tumor-related genes, reverse chromosome painting allows us to search for as yet unidentified amplified domains. Here, we report the analysis of a glioblastoma multiforme by reverse chromosome painting. Hybridization signals were found on chromosome 7p12-13 and chromosome 9q12-13. Standard Southern blot analysis revealed amplification of the EGFR gene, which is localized on band 7p13. These findings corroborate previous reports on coamplification of sequences on different chromosomes in glioblastoma.

Aged↗
PubMed1994

Debrisoquine hydroxylase gene polymorphism in meningioma.

Cytochrome P450 CYP2D6 polymorphism is an autosomal recessive trait associated with impaired debrisoquine metabolism in 5-10% of caucasian populations. This polymorphism has been associated with susceptibility to Parkinson's disease, bladder cancer, various forms of leukemia and possibly melanoma. In many other cancer forms, the data remained contradictory due to the technical limitations for identifying affected individuals (poor metabolizers). A recently developed polymerase chain reaction-based assay allows convenient screening of approximately 80% of known mutations. We have tested brain tumors correlated with chromosome 22 deviations for genetic polymorphism in the cytochrome P450 CYP2D6 locus localized on chromosome 22q13. Thirty-one meningioma samples were analyzed and the observed frequency of heterozygotes and homozygotes for the G to A mutation did not deviate significantly from the distribution in a normal population. These data are comparable to previous observations in for example breast and colon cancer and indicate that the CYP2D6 locus on chromosome 22q13 is not involved in the pathogenesis of meningiomas.

Alleles↗
PubMed1994

DNA amplifications on chromosomes 7, 9 and 12 in glioblastoma detected by reverse chromosome painting.

Biopsies and cell culture, respectively, of four human glioblastoma multiforme (WHO 4) have been evaluated for gene amplification using reverse chromosome painting. Three of the tumours showed amplified domains within chromosome bands 12q13-15. The exact localisation and extension of the amplified domains, however, varies within this region. Southern blot analysis revealed amplification of the GLI oncogene in two of the glioblastomas which were found to contain amplified domains within 12q13-15. Reverse chromosome painting also identified amplified domains within bands 7q21 and 9p23-24. Amplification within region 9p23-24 has previously not been reported in glioblastoma. The amplified domain encompassing 9p23-24 was detected in the same glioblastoma which contained an amplification unit within bands 12q13-14. These data, together with previous reports, indicate that amplifications are predominantly found on chromosomes 7, 9 and 12 in glioblastoma. In addition, this study provides further evidence that coamplification is not a rare event in glioblastoma.

Chromosomes, Human, Pair 12↗
PubMed1994

Strategy for chromosomal assignment of expressed sequences derived from heteronuclear RNA.

The chromosomal localization of transcribed sequences/genes is one of the objectives of the human genome project. Here, we describe a novel strategy for fast and dependable chromosomal assignment of expressed sequences that contain Alu sequences. Alu-PCR was performed on cDNA that was derived from heteronuclear (hn) RNA. hn-cDNA libraries are utilized for the identification of genes from extended human chromosomal regions or entire chromosomes. For chromosomal assignment, Alu-PCR products larger than 500 bp were hybridized against genomic DNA of somatic cell hybrids that was also amplified by Alu-PCR. Hybridization signals obtained within 2-3 h of exposure allow localization of cDNA-derived Alu-PCR products to single chromosomes. This technique is particularly useful for the analysis of cDNA libraries derived from hn-RNA. Using hn-cDNA clones from different chromosomes, we demonstrate the accuracy and reliability of the mapping strategy.

Animals↗
PubMed1993

Cosmid mapping and locus linkage within the human chromosomal region 22q13.1.

Many human meningiomas show loss of heterozygosity at distal loci but retain constitutional heterozygosity at one or more proximal loci of 22q. Molecular analysis indicted deletions involving at least the region 22q12.3-qter. In this region, distal to myoglobin, the putative meningioma locus ought to be expected. Long-range mapping was performed around two loci from 22q12.3-q13.1 (D22S16 and PDGFB, the most proximal locus to be lost in meningioma). D22S16, originally assigned to 22q13-qter by isotopic in situ hybridization, was placed in the vicinity of PDGFB by utilizing a set of somatic cell hybrids, an assignment confirmed by fluorescence in situ hybridization (FISH) of a cosmid clone containing the D22S16 locus. Moreover, pulsed field gel electrophoresis suggests a close linkage of both markers within 630 kb.

Arachnoid↗
PubMed1993

Generation of a chromosome-22-specific c-DNA library as confirmed by FISH analysis.

We have recently developed a strategy for the rapid enrichment of c-DNA fragments from selected human chromosomes. Heteronuclear RNA (hn-RNA) is isolated from a somatic cell hybrid that retains a single human chromosome in a rodent background. Following c-DNA synthesis, human sequences are selectively amplified by the Alu polymerase chain reaction (Alu-PCR). Here we have applied this protocol for the selective isolation of novel c-DNAs encoded by chromosome 22. Fluorescence in situ hybridization has been used to confirm the chromosome-22-specific origin of the c-DNA fragments. Controls show DNAse-free RNase-treated hn-RNA results in no c-DNAs or Alu-PCR products. As demonstrated by competitive in situ suppression hybridization (CISS), the majority of the Alu-PCR products from hybrid GM 10027 are located on chromosome 22. Without competition, hybridization signals have also been identified on other human chromosomes. These unspecific hybridization signals result from Alu sequences and can successfully be reduced by competition with cot 1 DNA. This is the first report of the use of CISS for the localization of chromosome-specific c-DNAs.

Animals↗
PubMed1993

Amplified met gene linked to double minutes in human glioblastoma.

The met proto-oncogene was found to be amplified in a human glioblastoma cell line (T3095) established from a glioblastoma multiform WHO grade IV. Amplification of epidermal growth factor receptor, transforming growth factor alpha and N-myc which have been described previously in glioblastoma were not observed in T3095. There was, however, an 8-fold met amplification. Giemsa-stained metaphases of T3095 cells revealed multiple (> 5) double minutes (dmins) in the majority of cells. Following xenografting in nude mice there was a significant increase in the number and frequency of dmins. The increase in dmins correlates with the level of met amplification (50-fold), suggesting localisation of the amplified met on dmins. Here we report the first case of met amplification in glioblastoma. Correlation between met amplification and extrachromosomal elements (dmins) has not been reported previously.

Animals↗
PubMed1993

Identification of chromosome-specific sequence-tagged sites by Alu-PCR.

Recently, methods have been developed for the isolation of expressed sequences from particular human chromosomes. Using Alu consensus sequences as primers, cDNA synthesis has been initiated from interspecies hybrid cell lines that contain single human chromosomes. Alu consensus sequences have also been utilized to amplify human genomic sequences via polymerase chain reaction (PCR). Here, we describe the use of Alu-PCR to isolate expressed sequences from human chromosomes selectively. Heteronuclear (hn) RNA is transcribed into cDNA by using poly-(dT)15 primer sequences. Subsequently, human specific cDNA sequences are amplified by Alu-PCR and cloned into pBluescript. To verify the chromosomal assignment, cloned PCR products are sequenced, converted into STS markers, and tested on a different somatic hybrid that contains human chromosome 22. The method provides a fast, reliable way to identify expressed sequence tagged sites from selected human chromosomes.

Animals↗
PubMed1991

Loss of heterozygosity for loci on the long arm of chromosome 6 in human malignant melanoma.

Malignant melanoma has been documented to display recurring abnormalities of chromosome 6, particularly the long arm (6q). Restriction fragment length polymorphism analysis was used as a molecular genetic approach to examine loci on chromosome 6q for loss of constitutional heterozygosity (LOH). Five DNA markers that recognize restriction fragment length polymorphisms along 6q and one polymorphic DNA marker for 6p were used to screen 20 autologous pairs of tumor DNA and normal DNA to determine the tumor and constitutional genotypes of each patient. LOH on chromosome 6q was identified at 21 of 53 informative loci (40%). Five patients with more than one informative locus had allele losses consistent with the loss of the entire long arm (or of an entire copy) of chromosome 6, while four other patients demonstrated terminal deletions of 6q. The chromosomal region bearing the highest frequency of 6q allelic loss (60%) is defined by the marker loci c-MYB and ESR (6q22-23 and 6q24-27). In contrast to the frequency of 6q loss, LOH was observed at loci on four other chromosomes (1, 11, 16, 17) in only 5% of cases. These results have led us to conclude that the loss of sequences from the long arm of chromosome 6 is a nonrandom and possibly biologically relevant event in human malignant melanoma.

Alleles↗
PubMed1991

Large-scale physical mapping within the region 22q12.3-13.1 in meningioma.

The lack of physical mapping data strongly restricts the analysis of the meningioma chromosomal region that was assigned to the bands 22q12.3-qter. Recently, we reported a new marker D22S16 for chromosome 22 that was assigned to the region 22q13-qter by in situ hybridization. Utilizing somatic cell hybrids we now sublocalized the marker D22S16 within the band region 22q12-13.1, thus placing it in the vicinity of the gene for the platelet derived growth factor (PDGFB). A physical map was established for the regions surrounding the PDGFB gene and the D22S16 marker. By means of pulsed-field gel electrophoresis (PFGE) D22S16 and PDGFB were found to be physically linked within 900 kb. We also identified two CpG clusters bordering the PDGFB gene. For the enzyme NotI, a variation of the PDGFB restriction pattern was found between different individuals. PFGE analysis of the two loci (PDFGB and D22S16) failed to identify major rearrangements in meningioma.

Animals↗
PubMed1989

Molecular mapping of the oncogene MYB and rearrangements in malignant melanoma.

The human cellular oncogene MYB has been mapped to 6q22-q23. Deletions and translocations involving this region of the long arm of chromosome 6 occur frequently in human malignant melanoma, and there are anecdotal reports of MYB gene rearrangements in this cancer. In the current study, Southern blotting and pulsed field gel electrophoresis (PFGE) have been performed to determine whether MYB or its flanking regions are commonly altered in malignant melanoma. Southern blotting failed to document obvious rearrangement of the MYB gene in 15 cases studied. To extend analysis of the MYB region, a long-range restriction map was established by PFGE. This map was then linked to the known restriction map of frequent cutting enzymes. Based on the mapping data and analysis of the MYB region in melanomas, ClaI tissue-specific variation due to methylation was demonstrated. Also, two melanomas (containing alterations in band 6q13) also demonstrated by PFGE a unique restriction fragment for the MYB gene. These results extend significantly the physical map surrounding the MYB locus and provide further evidence for the rearrangement of chromosome 6 in malignant melanoma.

Blotting, Southern↗