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S Strehl

Publications and source records attributed to S Strehl.

31 records · Page 2Linked to original sources
PubMed1994

Diagnostic value of the molecular genetic detection of the t(11;22) translocation in Ewing's tumours.

One consistent feature of the Ewing's tumour family is the presence of a balanced translocation involving band q12 and band q24 of chromosome 22 and chromosome 11. Recent cloning of the chromosome breakpoint regions of t(11;22)(q24;q12) Ewing's sarcoma translocation has revealed that the breakpoints were localized within the Ewing's sarcoma gene (EWS gene) on chromosome 22 and the Fli-1 gene on chromosome 11. Molecular genetic techniques can thus be applied to the detection of the t(11;22) translocation in Ewing's tumours. By reverse transcription and polymerase chain reaction technique (RT-PCR) 11 Ewing's tumour derived cell lines, 12 primary Ewing's tumours, and 11 tumours after treatment were analysed for the occurence of the t(11;22) translocation. Furthermore, blood and bone marrow samples from 5 patients were available for RT-PCR. In 78% of the cell lines and 91% of the primary Ewing's tumours the t(11;22) translocation was detectable by RT-PCR. In bone marrow samples from a Ewing's sarcoma patient presenting in relapse tumour cells were detected by molecular genetic analysis. Our results indicate that molecular genetic detection of the t(11;22) translocation is valuable in the differential diagnosis of small round cell tumours and will provide important information for the staging and prognosis of Ewing's tumour.

Base Sequence↗
PubMed1994

Variability of EWS chimaeric transcripts in Ewing tumours: a comparison of clinical and molecular data.

Ewing tumours (ET), including Ewing's sarcoma and peripheral primitive neuroectodermal tumour, are well characterised at the molecular level by a unique chromosomal rearrangement which fuses the EWS gene to one of two closely related ETS proto-oncogenes, FLI-1 or ERG. Expression of the resulting chimaeric transcripts can be readily detected by reversed transcriptase polymerase chain reaction (RT-PCR). This approach led to the identification of a number of different exon combinations at the junction site of coding sequences. The physiological consequences of the observed variability in the hinge region of EWS chimaeric proteins are not known. We have analysed tumour-derived material from 30 ET patients with well-documented clinical course (18 with localised and 12 with metastatic disease at diagnosis) for the presence of EWS/FLI-1 or EWS/ERG RNA. Karyotypes were obtained in 21 out of 27 cases and analysed by routine cytogenetics. A chromosome 22 rearrangement was demonstrated in 18 cases (67%). In contrast, RT-PCR revealed the presence of chimaeric transcripts in 28 tumours (93%), with fusions of EWS exon 7 to FLI-1 exons 6 (19/28), 5 (4/28) and 7 (1/28). In addition, EWS/FLI-1 exon combinations 10/5 and 9/4 were observed in one case each. In the last tumour, the presence of at least four additional splicing variants corresponding to fusion of EWS exon 7 to FLI-1 exons 4, 6, 8 and 9 was demonstrated. Two tumours expressed EWS/ERG fusion transcripts involving EWS exon 7 and ERG exon 6. In this study, EWS/FLI-1 exon combinations 7/6 (type I) predominated over 7/5 (type II) in localised ET (14 versus 1) and were more abundant in tumours affecting the long bones (9 versus 0), whereas in central axis tumours and metastatic disease there was only little difference in the frequency of the two types. So far, no correlations between different chimaeric EWS transcripts and any other clinical parameters have been identified.

Adolescent↗
PubMed1993

Non-random integration of Epstein-Barr virus in lymphoblastoid cell lines.

In order to examine the role of Epstein-Barr virus (EBV) in the immortalization of human B lymphocytes and in the pathogenesis of lymphoid malignancies, we investigated whether the EBV integration into the human genome is randomly distributed or whether the virus integrates preferentially at certain sites. Twelve in vitro immortalized human lymphoblastoid cell lines (LCLs), two in vivo infected LCLs, and one Burkitt's lymphoma cell line (EB2) were examined by non-radioactive in situ hybridization (ISH) with a biotinylated EBV probe. Recurrent hybridization sites were detected in all 15 cell lines. The chromosomes frequently carrying the EBV genome were chromosomes 1, 2, 4, and 5. In more than 70 chromosomal bands, a greater number of integration sites than expected was found (p < 0.05). Approximately half of these bands were involved in the majority of the cell lines (for example, 1p31, 1q43, 2p22, 3q28, 4q13, 5p14, 5q12, and 11p15) whereby band 5p14 was involved in all LCLs analyzed. Virtually no viral integrations were found on the sex chromosomes (X, Y). The majority of the EBV integrations was found in G-band-positive material (p < 0.0001). Thus, our findings clearly show that EBV integrates into the human genome in a non-random manner.

Adolescent↗
PubMed1993

Translocation (12;13) in a case of infantile fibrosarcoma.

Cytogenetic analysis of an infantile fibrosarcoma showed the presence of a t(12;13) and numerical changes of chromosomes 15 and 20. Until now only non-random gain or loss of total chromosomes as well as one case with a deletion at 17p have been reported for this kind of tumor. This report represents the first cytogenetic description of an aggressive infantile fibrosarcoma with a translocation.

Chromosomes, Human, Pair 12↗
PubMed1993

Fluorescence in situ hybridization combined with immunohistochemistry for highly sensitive detection of chromosome 1 aberrations in neuroblastoma.

The development and application of a highly sensitive double-target fluorescence in situ hybridization (FISH) method in combination with immunohistochemistry for detection of chromosome 1 abnormalities in interphase nuclei of neuroblastoma samples is reported. An alpha-satellite probe specific for chromosome 1 and a VNTR probe that hybridizes to chromosome band 1p36.3 were hybridized to GD2 prestained neuroblastoma cells in double-target FISH experiments. The ratio of intact to deleted chromosome 1 homologs in the neuroblastoma cells was assessed. To demonstrate the reliability of the method described, four selected samples derived from different neuroblastoma stages are presented. FISH results correlated well with data obtained by conventional cytogenetic procedures. The technique described allows sensitive detection of chromosome 1 abnormalities in interphase nuclei and enables partial cytogenetic analysis of nondividing cells with a defined immunological phenotype.

Antigens, Neoplasm↗
PubMed1992

Ewing's tumor X mouse hybrids expressing the MIC2 antigen: analyses using fluorescence CDD-banding and non-isotopic ISH.

We present a highly sensitive method that has been applied to map the chromosomal origin of the prominent cell surface antigen of Ewing's tumor cells recognized by monoclonal antibody HBA-71. The technique allows an unambiguous identification of human chromosomal material in interspecific cell hybrids. This is achieved by fluorescent in situ hybridization of biotinylated total human DNA, followed by high resolution fluorescence banding with the chromomycin/distamycin/DAPI triple stain. An advantage of this method is that all signals can be visualized in one single operation by simply switching the appropriate filter blocks. The protocol has proved extremely useful in gene mapping by means of interspecific cell hybrids, a technique that depends on the accurate and unambiguous recognition of the relevant (e.g., human) genetic material in the clonal genome. Our studies confirm that this antigen is the product of the MIC2 gene, which is so far the only well-studied pseudoautosomal gene in man, and which is located on the short arms of chromosomes X and Y. Furthermore, no influence of the Ewing's tumor-specific translocation t(11;22) on MIC2 expression could be discerned.

Animals↗
PubMed1992

Structure of the human TNF receptor 1 (p60) gene (TNFR1) and localization to chromosome 12p13 [corrected].

Clones encoding the entire coding and 3' untranslated region of the human type I tumor necrosis factor receptor (p60) gene (TNFR1) were isolated by hybridization using probes derived from TNFR-1 cDNA. The gene was characterized by restriction mapping. DNA blot analysis and sequence analysis. The coding region and the 3' untranslated region are distributed over 10 exons. Each of the four repeats, comprising the extracellular ligand binding domain and characterizing a receptor superfamily, is interrupted by an intron. However, the intron-exon structure is not conserved in the nerve growth factor receptor gene, another member of this superfamily. By PCR analysis of human-mouse somatic cell hybrids and in situ hybridization using biotinylated genomic TNFR1 DNA, we localized the gene to human chromosomal band 12p13. This corresponds to the homologous murine gene localized at the distal region of mouse chromosome 6.

Amino Acid Sequence↗
PubMed1991

MIC2 is a specific marker for Ewing's sarcoma and peripheral primitive neuroectodermal tumors. Evidence for a common histogenesis of Ewing's sarcoma and peripheral primitive neuroectodermal tumors from MIC2 expression and specific chromosome aberration.

This study reports on the specific expression of the MIC2 gene, a pseudoautosomal gene located on the short arms of the X and Y chromosomes, on Ewing's sarcoma (ES) and peripheral primitive neuroectodermal tumor (pPNET) cells. The gene product, a cell membrane protein, is recognized by the newly established monoclonal antibody (MoAb) HBA-71 and the previously described MoAb 12E7 and RFB-1. Furthermore, the reaction pattern of the MIC2 antibodies, especially HBA-71, with normal tissues and a great number of benign and malignant tumors (70 different tumors, 199 tumor samples), as well as the correlation between the specific chromosomal aberrations, i.e., the t(11;22) and the del(22) and the expression of this antigen, are demonstrated. Both ES and pPNET cells express the MIC2 gene in very high amounts, which represents a highly selective and almost unique feature of these cells, making an assignment of these tumors in one entity even more likely. The MIC2 antibodies are of great value for clinical and research purposes.

12E7 Antigen↗
PubMed1991

A novel putative tyrosine kinase receptor with oncogenic potential.

We have detected transforming activity by a tumorigenicity assay using NIH3T3 cells transfected with DNA from a chronic myeloproliferative disorder patient. Here, we report the cDNA cloning of the corresponding oncogene, designated UFO, in allusion to the as yet unidentified function of its protein. Nucleotide sequence analysis of a 3116bp cDNA clone revealed a 2682-bp-long open reading frame capable of directing the synthesis of a 894 amino acid polypeptide. The predicted UFO protein exhibits characteristic features of a transmembrane receptor with associated tyrosine kinase activity. The UFO proto-oncogene maps to human chromosome 19q13.1 and is transcribed into two 5.0 kb and 3.2 kb mRNAs in human bone marrow and human tumor cell lines. The UFO locus is evolutionarily conserved between vertebrate species. A 4.0 kb mRNA of the murine UFO homolog is expressed in a variety of different mouse tissues. We thus have identified a novel element of the complex signaling network involved in the control of cell proliferation and differentiation.

Amino Acid Sequence↗
PubMed1990

Overexpression of the pseudoautosomal gene MIC2 in Ewing's sarcoma and peripheral primitive neuroectodermal tumor.

Ewing's Sarcoma (ES), the second most frequent bone tumor in childhood and adolescence, and the probably closely related peripheral primitive neuroectodermal tumor (pPNET) share a unique cytogenetic translocation between chromosomes 11 and 22. Both of them expose high amounts of a glycoprotein on their cell surface, which can be specifically detected by the mAb HBA-71. The cDNA coding for the HBA-71 antigen was isolated by screening a cDNA expression library constructed from a pPNET-derived cell line. Nucleotide sequencing revealed the HBA-71 antigen to be the product of the pseudoautosomal gene MIC2 previously identified by the mAb 12E7 in haematopoietic cells. This antigen is a glycoprotein with a molecular weight of about 29,000 and is expressed in low amounts in most human cell lines and probably normal tissues and tumors with only a few exceptions. In T-cells the antigen is involved in cell adhesion processes. In ES- and pPNET-derived cell lines MIC2 expression is significantly enhanced. No gross changes in posttranslational modification could be observed. The high expression results in easy and specific detection of the antigen in immunocytochemical analysis of paraffin embedded tissue sections making HBA-71 a useful tool in tumor diagnosis.

12E7 Antigen↗
PubMed1985

Prognostic significance of immunologic phenotype in hairy cell leukemia: does it exist?

Of 94 hairy cell leukemia (HCL) patients studied for immunologic phenotype of their hairy cells, 89 patients had B cell markers and five patients were both surface immunoglobulin (slg) negative and E rosette negative. Forty of the 77 cases that had the heavy chains individually determined had IgG only (52.0%); 23 others had IgG in addition to other Ig heavy chains. Seventy-nine patients had monoclonal light chains; 65 with kappa chain and 14 with lambda chain. The only significant difference with respect to survival among the various slg groups occurred between the kappa chain and the lambda chain groups. Within the first 46 months after diagnosis of HCL, 20 deaths occurred among the 65 kappa chain patients, whereas the first and only death among the lambda chain patients occurred at 68 months after diagnosis. The only clinical or laboratory parameter that was significantly different between these two immunologic subgroups was the incidence of infections. Among the lambda chain patients, an infectious complication rate of 28.6% was observed subsequent to the diagnosis of HCL, whereas this rate was 68.8% in kappa chain patients (P = .005). The survival of lambda patients was found to exceed that of the kappa patients by the generalized Wilcoxon test (P = .03). However, when the log rank test was used, no significant difference was detected (P = .13).

Humans↗
PubMedDate not supplied

[Cytogenetic aspects of pediatric germ cell tumors].

We have performed in situ hybridization (ISH) studies predominantly on paraffin sections and on isolated nuclei of 22 pediatric germ cell tumors (GCTs) from 18 patients including 4 recurrences from three patients. In addition, we performed conventional cytogenetic analyses in three tumor samples. Because reports on cytogenetic studies in pediatric GCTs are scarce we focused our studies on those chromosome abnormalities frequently observed in adult GCTs. These included numeric and structural abnormalities of chromosomes 1 and 12 (e.g. isochromosome 12p) and numeric deviations of chromosomes 8, 10, X and Y. The histological subsets of the tumors investigated included two dysgerminomas (DGE), one seminoma (SE), one combined seminoma, two embryonal carcinomas (EC), two recurrent ECs, six pure yolk sac tumors (YST), five combined teratomas, one immature teratoma (IT) and two recurrences of IT, and three differentiated teratomas (TD). Similar to the GCTs in adults, additional copies of chromosome 12 were the most frequently observed numeric abnormalities. The analysis of two paraffin-embedded tumors suggested that changes in the size of the pericentromeric hybridization signals of chromosome 12 may be attributed to the presence of i(12)(p10). This was confirmed following the karyotype analysis of one EC which unequivocally revealed the presence of two i(12)(p10). Interestingly, using these probes, no chromosomal abnormalities were found in the pure TD or in the TD cells of mixed tumors containing a YST component. In the YST portion, however, the 1p deletions and/or numeric chromosome changes were present. Surprisingly, deletions at the short arm of chromosome 1, del(1)(p36.3), were frequently observed in malignant pediatric GCTs and were the sole abnormality detected in one case.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗