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E Meese

Publications and source records attributed to E Meese.

At least 19 recordsLinked to original sources
PubMed1999

Role of amplified genes in the production of autoantibodies.

A variety of previously published studies have shown the presence of autoantibodies directed against oncogenic proteins in the sera of patients with tumors. Generally the underlying genetic aberration responsible for the induction of an immune response directed against an abnormal protein is unknown. In our studies we analyzed the role of gene amplification in the production of autoantibodies in squamous cell lung carcinoma. We screened a cDNA expression library with autologous patient serum and characterized the isolated cDNA clones encoding tumor expressed antigens termed LCEA (lung carcinoma expressed antigens). As determined by sequence analysis, the 35 identified cDNA clones represent 19 different genes of both known and unknown function. The spectrum of different clones were mapped by polymerase chain reaction (PCR) and fluorescence in-situ hybridization, showing that a majority are located on chromosome 3, which is frequently affected by chromosomal abnormalities in lung cancer. Gene amplification of 14 genes was analyzed by comparative PCR. Nine genes (65% of all analyzed genes) were found to be amplified; furthermore, most of them are also overrepresented in the pool of cDNA clones, suggesting an overexpression in the corresponding tumor. These results strongly suggest that gene amplification is one possible mechanism for the expression of immunoreactive antigens in squamous cell lung carcinoma.

Antigens, Neoplasm↗
PubMed1999

Expression analysis of genes at 3q26-q27 involved in frequent amplification in squamous cell lung carcinoma.

Gene amplifications are known to occur frequently in lung cancer. Recently, we identified gene amplifications at 3q26 in squamous cell lung carcinoma (SCC) using reverse chromosome painting. Here, our aim was to analyse the expression of genes which map within the amplified chromosomal region. The genes which were selected for their known function and their potential involvement in tumour development included the genes for ribosomal protein L22 (RPL22), butyrylcholinesterase (BCHE), glucose transporter 2 (SLC2A2), transferrin receptor (TFRC), thrombopoietin (THPO) and the phosphatidylinositol-3 kinase catalytic alpha polypeptide (PIK3CA). While five genes were expressed in the majority of the 17 samples of SCC, the gene for the glucose transporter 2 (SLC2A2) was expressed in only three cases, excluding SLC2A2 as the target gene of the amplification unit. For a subset of tumours, we determined the amplification status of the six genes. The TFRC, PIK3CA, BCHE, THPO and SLC2A2 genes were amplified in several cases, whereas the RPL22 gene was amplified in only one case. The combined amplification and expression data of this and our previous studies indicate that the amplified region at 3q26 contains several genes that are transcribed in SCC, providing the possibility that several amplified and functionally important genes at 3q26 may be involved in the pathogenesis of SCC.

Blotting, Southern↗
PubMed1999

Five novel immunogenic antigens in meningioma: cloning, expression analysis, and chromosomal mapping.

Tumorigenesis of meningioma has been associated with chromosome 22, most notably the NF2 gene, but additional genes have been implicated in meningioma development. Here, we report the identification of five novel immunogenic antigens expressed in meningioma. An expression library was generated from a meningioma that retained both copies of chromosome 22. Screening with autologous patient serum identified seven cDNA clones that were indicated by antigen-antibody complexes. The clones were sequenced, and sequence comparison revealed that the seven clones represent five different genes, providing evidence that meningiomas express a spectrum of immunoreactive antigens, which were termed meningioma expressed antigens (MGEAs). One gene was identical with the connective tissue growth factor, one gene was in part homologous to an Alzheimer disease-associated gene, and a third gene was in part identical to Homo sapiens molybdenum cofactor biosynthesis proteins A and C mRNA. One gene was partially homologous to previously reported cDNA sequences of unknown function, and the fifth gene showed no significant homologies to sequences deposited in databases. Using somatic hybrid mapping, three genes were localized on chromosome 6, and two genes were localized on chromosomes 3 and 17, respectively. To distinguish the MGEAs from the so-called natural autoantigenes, we also screened the library with 12 sera from individuals without obvious disease. The clones identified by reactivity with normal sera were completely different from the clones identified by screening the same meningioma expression library with serum from the patient bearing the tumor. These data suggest that the newly identified MGEA genes may be useful for diagnosis and possibly therapy of meningioma.

Algorithms↗
PubMed1998

Lymphocyte-specific chemokine receptor CXCR3: regulation, chemokine binding and gene localization.

Expression of CXCR3, the receptor for the CXC chemokines IFN-gamma-inducible 10-kDa protein (IP10) and monokine induced by IFN-gamma (Mig), in human T lymphocytes and their responses to IP10 and Mig were analyzed. About 40 % of resting T lymphocytes (and low numbers of B cells and natural killer cells) stained positive for CXCR3 but these cells did not express CXCR3 transcripts and did not respond to these chemokines. However, treatment with IL-2 with or without addition of phytohemagglutinin for 10 or more days resulted in cultures of fully responsive, CXCR3-positive T lymphocytes. Treatment with anti-CD3 antibodies in the presence or absence of soluble anti-CD28 antibodies was inhibitory. Addition of chondroitin sulfate C to CXCR3-expressing murine pre-B cells allowed the determination of high-affinity binding for Mig and IP10 with Kd of 0.9-1.2 nM and 0.2-0.3 nM, respectively, and 1.3 x 10(4) binding sites per cell. The gene for CXCR3 was localized on human chromosome Xq13 which is in clear contrast to all other chemokine receptor genes, suggesting unique function(s) for this receptor and its ligands that may lie beyond their established role in T cell-dependent immunity.

Chemokine CXCL10↗
PubMed1998

Novel immunogenic antigen homologous to hyaluronidase in meningioma.

By screening a meningioma expression library with autologous serum we identified four cDNA clones representing a novel gene with striking homology to Caenorhabditis elegans hyaluronidase as indicated by BLASTP analysis. In humans hyaluronidase has been implicated in cancer development and three human genes are known to encode proteins with hyaluronidase activity. None of the human genes, however, showed any homology at the nucleotide or amino acid sequence level to the newly isolated antigen we termed meningioma expressed antigen 5 (MGEA5). Somatic cell hybrid mapping and fluorescence in situ hybridization mapped the gene for MGEA5 to chromosomal band 10q24.1-q24.3. Reverse transcription (RT)-PCR and northern blot hybridization revealed expression of the gene encoding MGEA5 in several meningioma and additional human tissues. Expression analysis also indicated an alternative splicing event giving rise to a shorter and altered transcript termed MGEA5s. The expression of MGEA5 and MGEA5s as fusion proteins revealed an approximate molecular weight of 92 and 54 kDa, respectively. Using heterologous sera we found antibodies against MGEA5s in five out of 23 meningioma patients, whereas no immune reaction was detected in 12 control sera from healthy individuals. Confirmation of hyaluronidase activity was independently achieved by turbidometric analysis and a gel matrix assay. A model for involvement of the novel hyaluronidase gene in meningioma development is proposed.

Acetylglucosaminidase↗
PubMed1998

Human endogenous retrovirus K homologous sequences and their coding capacity in Old World primates.

The coding capacity for retroviral Gag and Env proteins has been maintained in human endogenous retroviruses of the HERV-K family. HERV-K homologous sequences have been found in all Old World primates. Here, we examined Old World primate species for the presence of full-length HERV-K gag and env genes and the presence of gag and env open reading frames as determined by the protein truncation test. Full-length HERV-K env genes were found in DNAs of all Old World primate species, whereas open reading frames for Env protein were found solely in human, chimpanzee, and gorilla DNAs. The mutational event leading to two HERV-K types was found to have occurred after the separation of hominids from lower Old World primates and before the expansion of hominids. Full-length HERV-K gag genes in hominids displayed a 96-bp deletion compared to those in lower Old World primates. The ancient gag variant has not been maintained during hominid evolution. Open reading frames for HERV-K Gag have been found in all Old World primates except chimpanzees. Our study of the HERV-K family during Old World primate evolution contributes to the understanding of their possible biological functions in the host genomes.

Animals↗
PubMed1997

TYMSTR, a putative chemokine receptor selectively expressed in activated T cells, exhibits HIV-1 coreceptor function.

BACKGROUND: Chemokines bind to specific receptors and mediate leukocyte migration to sites of inflammation. Recently, some chemokine receptors, notably CXCR4 and CCR5, have been shown to be essential fusion factors on target cells for infection by human immunodeficiency virus (HIV); the chemokines bound by these receptors have also been shown to act as potent inhibitors of HIV infection. Here, we describe the isolation of a novel, putative chemokine receptor. RESULTS: We have isolated the cDNA for a putative human chemokine receptor, which we have termed TYMSTR (T-lymphocyte-expressed seven-transmembrane domain receptor). The TYMSTR gene is localized to human chromosome 3 and encodes a protein that has a high level of identity with chemokine receptors. TYMSTR mRNA was selectively expressed in interleukin-2-stimulated T lymphocytes but not in freshly isolated lymphocytes and leukocytes or related cell lines. The natural ligand for TYMSTR was not identified among 32 human chemokines and other potential ligands. Cells co-expressing TYMSTR and human CD4 fused with cells expressing envelope glycoproteins of macrophage (M)-tropic HIV-1 as well as T-cell line (T)-tropic HIV-1 isolates. Addition of infectious, T-tropic HIV-1 particles to TYMSTR/CD4-expressing cells resulted in viral entry and proviral DNA formation. CONCLUSIONS: Our findings demonstrate that TYMSTR, in combination with CD4, mediates HIV-1 fusion and entry. The high-level expression of TYMSTR in CD4(+) T lymphocytes and the selectivity of this receptor for T-tropic and M-tropic HIV-1 strains indicates that TYMSTR might function as HIV coreceptor at both early and late stages of infection.

Amino Acid Sequence↗
PubMed1997

Identification of an amplified gene cluster in glioma including two novel amplified genes isolated by exon trapping.

Gene amplification, which occurs in more than 50% of malignant gliomas, is considered to play a pivotal role in tumorigenesis. There are, however, few studies aimed toward the isolation of novel genes from amplified sequences. Previously, we reported amplification of the protooncogene MET (hepatocyte growth factor receptor; 7q31) in more than 20% of glioblastomas. For an approximate size estimation of the amplification unit we analyzed three glioblastomas all of which carried an amplified MET gene, by Southern blot analysis and/or competitive polymerase chain reaction using eight DNA markers. Although the extent of the amplified domain varied, the close vicinity of the MET gene was the only region consistently amplified in these glioblastomas. A yeast artificial chromosome (YAC) contig of 900 kb was refined spanning the amplified region flanking the MET gene. The YAC inserts were subcloned into 59 cosmids, which were used for exon trapping. Eight sequences were identical to parts of the genes MET and CAPZA2 (human actin capping protein alpha-subunit). Two newly identified exons and the CAPZA2 exons were amplified in tumor TX3095, which retains an amplified MET gene. The new exons were localized close to MET and CAPZA2. Characterization of the clones, which were termed glioma-amplified sequence (GAS)7-1 and GAS7-2, showed an open reading frame and a different expression pattern in multiple human tissues. This study reports the identification of a cluster of amplified genes including two novel genes in a region amplified in more than 20% of glioblastomas.

Actin Capping Proteins↗
PubMed1997

Translation initiation factor eIF-4gamma is encoded by an amplified gene and induces an immune response in squamous cell lung carcinoma.

Amplification of cellular oncogenes is an important mechanism of altered gene expression in human cancers. Using comparative genomic hybridization we recently identified an amplification at 3q26.1-q26.3 in 30% of squamous cell carcinomas of the lung. A variety of methods including microdissection-mediated procedures permit cloning of genes encoded within amplified domains but do not directly lead to the identification of biologically relevant genes. In this study, we have circumvented this problem by combining an immunological and molecular genetic approach to analyze squamous cell lung carcinoma. To identify both amplified and tumor relevant genes, we generated a cDNA expression library from a tumor with the 3q amplification and hybridized the expressed recombinant polypeptides with the autologous serum. Of 400000 cDNA clones we identified 17 antigens which induce an immune response in a patient with squamous cell lung carcinoma. While most clones represent individual genes sequence analysis revealed that four of the 17 cDNAs are nearly identical with the eukaryotic translation initiation factor (eIF)-4gamma recently assigned on 3q. We demonstrated that the gene for eIF-4gamma was amplified within 3q26-q27 in independent squamous cell lung carcinomas. In this study, we report the identification of several antigens which elicit an immune response in a squamous cell lung carcinoma patient including eIF-4gamma. eIF-4gamma is encoded by an amplified gene and possibly plays a crucial part in the development of squamous cell lung carcinoma.

Base Sequence↗
PubMed1997

Cloning of a novel transcription factor-like gene amplified in human glioma including astrocytoma grade I.

Gene amplification, which is generally considered to occur late in tumor development, is a common feature of high grade glioma. Up until now, there have been no reports on amplification in astrocytoma grade I. In this study, we report cloning and sequencing of a cDNA termed glioma-amplified sequence (GAS41) which was identified recently in a glioblastoma cell line by microdissection-mediated cDNA capture. This technique is tailored to isolate amplified genes from human tumors. An increased copy number of GAS41 was found in glioblastoma multiforme and astrocytoma III, and at a high frequency in astrocytoma grades I and II. Sequence comparison indicates a high homology between the GAS41 protein, the yeast and human AF-9 and the human ENL proteins. Both AF-9 and ENL belong to a new class of transcription factors, indicating that GAS41 might also represent a transcription factor. With GAS41 being the first gene found with increased copy number in low grade glioma, this study provides the first evidence that gene amplification can occur in early tumor development.

Amino Acid Sequence↗
PubMed1997

cDNA cloning and chromosomal mapping of a predicted coiled-coil proline-rich protein immunogenic in meningioma patients.

There is increasing evidence that tumor expressed genes induce immune responses in cancer patients. To identify meningioma expressed antigens, we established a meningioma expression library which was screened with autologous serum. Out of 20 positive cDNA clones eight share high sequence homologies as determined by sequence analysis. These eight clones can be grouped into three classes which differ in length and which are characterized by specific sequence variations. The longest open reading frame was found to be 2412 bp encoding an immunoreactive antigen termed meningioma expressed antigen 6 (MEA6). Using five sequence specific primer pairs, somatic hybrid panel mapping revealed locations of the three classes on several human chromosomes including chromosomes 2, 3, 6, 7, 9, 13 and 14. The mapping results were confirmed by fluorescence in situ hybridization. RT-PCR showed consistent expression of all classes in several meningiomas and additional tissues using the same set of primer pairs as for chromosomal mapping. The expression data were confirmed by northern blot analysis. For the predicted amino acid sequence BLASTX revealed a homology to a human C219-reactive peptide which was previously isolated by an antibody directed against p-glycoprotein. Sequence properties of the MEA protein include an acidic activation domain, a proline-rich region and two coiled-coil domains indicating protein binding and activation functions.

Amino Acid Sequence↗
PubMed1997

Multiple human endogenous retrovirus (HERV-K) loci with gag open reading frames in the human genome.

Human endogenous retrovirus HERV-K is present in 25-30 copies per haploid human genome. At least one of these loci is capable of producing full-length Gag protein, high amounts of which have been detected in germ cell tumors and derived cell lines. The latter display HERV-K Gag-encoded retroviral particles. Here, we employed the protein truncation test (PTT) in combination with a monochromosomal hybrid mapping panel to identify the human chromosomes harboring HERV-K gag genes with an open reading frame for Gag protein. Eight human chromosomes were found to contain intact HERV-K gag genes. PTT results were corroborated by partial sequencing of subregions from different HERV-K gag genes. The high number of HERV-K Gag open reading frames supports the idea of retroviral sequences retaining a biological benefit in the human genome.

Animals↗
PubMed1997

Chromosomal assignment of human endogenous retrovirus K (HERV-K) env open reading frames.

The haploid human genome contains at least one human endogenous retrovirus K (HERV-K) env gene displaying an open reading frame, as evidenced by the high antibody titers against HERV-K Env in germ cell tumor patients at the time of tumor detection. However, the chromosomal assignment of an intact HERV-K env sequence is complicated by the existence of 25-30 HERV-K copies per haploid human genome. Recently, we reported the application of the protein truncation test (PTT) to chromosomally assign HERV-K gag open reading frames. Here, we set out to determine the chromosomal distribution of full-length HERV-K env genes. As demonstrated by somatic hybrid mapping and the PTT, HERV-K env open reading frames were found on human chromosomes 7, 19, and Y. By sequencing chromosome-specific HERV-K env subregions, we assigned two recently reported intact HERV-K sequences on human chromosomes 7 and 19, respectively. Chromosomes 7 and 19 and the Y are furthermore candidates for harboring a putative completely intact HERV-K locus.

Chromosome Mapping↗
PubMed1997

Effect of changes in the CD44 gene on tumour cell invasion in gliomas.

Cell adhesion is a critical factor in the multistep process of tumour invasion. CD44 is one of the cell surface adhesion molecules responsible for interaction with hyaluronic acid, a component of the CNS extracellular matrix. The aim of the present study was to demonstrate whether alterations in the CD44 gene might account for different invasive behaviour. EcoRI restriction analysis by Southern blot hybridization revealed several additional hybridization signals in tissue specimens of two out of 16 patients with glioblastoma, indicating DNA rearrangements or point mutations, respectively, within the region of the CD44 gene. Expression patterns of CD44 isoforms in these two rearranged gliomas and in 28 other patients with malignant gliomas were analysed by RT-PCR. All cases displayed only the splice variant CD44H, which acts as hyaluronic acid receptor in glioma tumour cells. Tumour cell invasion was studied with Boyden chamber assays using hyaluronic acid as ligand and functional CD44H blocking antibody. Invasion of cells derived from those gliomas carrying the rearranged CD44 gene locus was decreased by about 50% compared with gliomas without rearrangement, indicating that the altered hybridization patterns in the two glioma samples influenced CD44H mediated glioma cell invasion through hyaluronic acid in vitro. Our results on CD44 isoform expression suggest that, in contrast to other solid tumours, gliomas seem to express only the CD44 variant. Genetic alterations within the CD44 gene might alter the binding domain of the receptor and thus account for different invasive behaviour in glioblastomas.

Alternative Splicing↗
PubMed1996

Regional localization of over 300 loci on human chromosome 22 using a somatic cell hybrid mapping panel.

A somatic cell hybrid panel, consisting of 25 cell lines, has been developed to localize loci subregionally on chromosome 22. Over 300 markers in the form of STSs or hybridization probes have been assigned to one of 24 unique regions or "bins" using this panel. This ordered collection of markers will aid in the assembly of physical maps and contigs of chromosome 22 and assist in positional cloning of disease loci mapped to chromosome 22.

Animals↗
PubMed1996

Twelve amplified and expressed genes localized in a single domain in glioma.

Gene amplification has been associated both with tumor stage and progression in human gliomas. Several distinct amplified loci have been identified by comparative genomic hybridization and Southern blot analysis. It has been increasingly recognized that amplified domains comprise multiple genes. Here, we demonstrate amplification of up to 12 different genes from an amplified domain at 12q13-15 that has been found in approximately 15% of astrocytomas and glioblastomas. The amplified genes were GLI, WNT1, MDM2, SAS, CDK4 OS-4, GAS16, GAS27, GAS41, GAS56, GAS 64 and GAS89. In one glioblastoma all 12 amplified genes were also found to be expressed. These results strongly warrant the search for as yet unidentified genes in regions previously reported to be amplified.

Animals↗