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E Thiel

Publications and source records attributed to E Thiel.

At least 163 records · Page 9Linked to original sources
PubMed1994

Expression of the wt1 Wilms' tumor gene by normal and malignant human melanocytes.

We report expression of the wt1 (Wilms' tumor) gene by cultured human melanoma cells. Using RNA polymerase chain reaction analysis, wt1 transcripts were detected in 7 of 9 melanoma cell lines but not in 5 normal melanocyte strains. In Northern blot analysis, steady-state wt1 mRNA levels were found in 2 of 4 melanoma lines but not in normal melanocytes. Sequence analysis of the wt1 cDNA expressed by melanoma cell line WM 902-B revealed the presence of 4 previously published splice variants but no evidence for mutations in the coding region. Previous work has shown that WT1 modulates transcription after binding to the early growth response (EGR)-1 sites present in the platelet-derived growth factor (PDGF)-A chain promoter; the PDGF-A chain gene is known to be expressed by various melanoma cell lines. Based on these findings, we studied the relationship of wt1 and PDGF-A chain gene expression in melanoma cell lines. Co-expression of the wt1 and the PDGF-A chain genes was observed in 2 melanoma cell lines with mutated p53 but not in 2 melanoma cell lines with wild-type p53; this result is consistent with a previous report showing that, in the context of absent or mutated p53, WT1 acts as a transcriptional activator, whereas in the presence of wild-type p53 it acts as a repressor.

Base Sequence↗
PubMed1994

Peroxidase expression in acute unclassified leukemias: ultrastructural studies in combination with immunophenotyping.

The lineage affinity of 61 cases of acute unclassified leukemias (AUL) was reevaluated by ultrastructural analysis of peroxidase expression (POEM) in combination with immunophenotyping. In 24 cases a significant proportion of the blasts displayed ultrastructural myeloperoxidase (UMPO) and in another 3 cases platelet peroxidase (UPPO) suggesting the allocation of these leukemias to the myeloid or megakaryoblastic lineage. No significant correlation between myeloid surface marker expression and POEM positivity could be detected, while the presence of the CD 19 or CD 24 antigen significantly correlated with POEM negativity. The detection of lymphoid markers on POEM+ blasts indicates, that these leukemias might be derived from bipotential progenitors, which have retained their lymphoid antigens during myeloid differentiation. In one case a bilineage leukemia with a POEM+/CD 19- and a POEM-/CD 19+ population could be identified by immunoelectron microscopical studies (IEM). The remaining 34 AUL cases were POEM negative. Combined data suggest that these cases probably derive from early lymphoid progenitors. Taken together, AUL are heterogenous in presentation and in their cellular origin including a major portion of cases with an unequivocal myeloid differentiation detectable by ultrastructural analysis of myeloperoxidase expression.

Acute Disease↗
PubMed1994

Immunophenotypic features of childhood and adult acute lymphoblastic leukemia (ALL): experience of the German Multicentre Trials ALL-BFM and GMALL.

Immunophenotyping prospectively performed in about 2800 children and adults within the framework of the German multicentre ALL trials revealed marked differences in frequency distribution of immunologic subgroups with a higher incidence of immature B-cell precursor and pre-T/T phenotypic features in adults. Detailed immunophenotypic characterization by applying monoclonal antibodies to lymphoid- and myeloid-associated antigens as well as non-lineage-restricted molecules underlined the diagnostic value of pan-B and pan-T antigens that were expressed in virtually all cases of B-cell precursor (CD19, CD24) or T-cell ALL (cytoplasmic CD3, CD7) for lineage affiliation of leukemic blasts. About 10% of children and 20% of adults disclosed simultaneous expression of lymphoid markers and at least one myeloid-lineage-associated antigen. Our data confirm that immunophenotyping in ALL provides a solid basis for a biologically oriented and reliable classification of this heterogeneous disease.

Adult↗
PubMed1994

Combination of mitoxantrone and etoposide in the treatment of myelodysplastic syndromes transformed into acute myeloid leukemia.

Mitoxantrone and etoposide have both been shown to be effective in de novo acute myeloid leukemia. Therefore, the combination of mitoxantrone and etoposide, the NOVE regimen, was examined in the treatment of myelodysplastic syndromes (MDS) transformed into acute myeloid leukemia (AML). Twenty-one previously untreated patients (eight females, thirteen males) with a median age of 56 years (range 28-67 years) were studied. Diagnosis of MDS was made within the range of six months to three years before transformation into AML occurred. The NOVE regimen consisted of mitoxantrone 10 mg/m2 day 1-5, and of etoposide 100 mg/m2 day 1-5. After one single course of therapy eleven patients achieved a complete remission (CR) and three patients a partial remission (PR). Nine patients (six in CR and three in PR) received a second course, and the PR was completed to a CR in one patient. Thus, the overall response rate was 66% (14/21 patients), and the CR rate was 57% (12/21 patients). Median duration of CR was 7 months (range 2-10 months). Median survival was 10 months (range 3-20 months) for complete responders and 3 months (range 1-10 months) for patients who did not achieve a CR. For patients with subsequent CR, median time of granulocytopenia (< 500/microliters) and thrombocytopenia (< 20.000/microliters) was 20 days and 18 days, respectively. In conclusion, the NOVE regimen appears to be effective in AML secondary to MDS. However, strategies for remission maintenance are warranted.

Adult↗
PubMed1994

Detection of HRX-FEL fusion transcripts in pre-pre-B-ALL with and without cytogenetic demonstration of t(4;11).

The t(4;11)(q21;q23) characterizes a distinct clinical entity of childhood and adult acute lymphoblastic leukemia (ALL) with a pre-pre-B-phenotype, monocytoid features, coexpression of CD15 and/or CDw65 and a dismal prognosis. The molecular correlate of the t(4;11) has been identified as a fusion transcript of HRX, a gene on 11q23 with homology to drosophila trithorax gene, and FEL, a serine-proline-rich gene on 4q21 of unknown function. The aim of the current study was to establish a reverse transcription-polymerase chain reaction (RT-PCR) approach for the rapid and sensitive detection of the HRX-FEL fusion transcript associated with the t(4;11). For this purpose, two groups of patients were studied: group A comprised cases with cytogenetically proven t(4;11) including three infant and four adult pre-pre-B-ALL, as well as the two cell lines RS4;11 and MV4;11. Group B consisted of ten adult pre-pre-B-ALL with the identical phenotype, but without cytogenetic confirmation of t(4;11). Using primers complementary to HRX and FEL cDNA sequences 300 to 500 bp 5' and 3' of published breakpoints, respectively, specific amplification products were obtained in all nine cases of group A and in nine of the ten cases of group B. Three different types of fusion transcripts were identified by sequence analysis with HRX breakpoints at nucleotides 4086 and 4218 and FEL breakpoints at nucleotides 1413, 1416, and 1458. These data indicate that RT-PCR allows the detection of HRX-FEL fusion transcripts in the vast majority of cytogenetically proven and immunophenotypically suspected t(4;11) ALL. Hence, this technique may allow identification of a further subset of high risk ALL and may also be useful for the monitoring of minimal residual disease in t(4;11) ALL.

Adult↗
PubMed1994

[Immunophenotyping of acute lymphatic leukemia: diagnostic aspects and clinical relevance].

During the past two decades immunophenotyping has yielded significant new information regarding the biological heterogeneity of ALL and has provided a solid basis for a biologically oriented and reliable classification of this disease. At present, lineage commitment of acute leukaemias can be achieved in more than 98% of cases by applying a standardized panel of mAbs to pan-B-cell (CD19, cyCD22), pan-T-cell (cyCD3, CD7) and pan-myeloid antigens (CD13, CD33, MPO) that are expressed either on the surface or in the cytoplasm of the earliest progenitors of the respective cell lineage. Further subclassification of ALL based on the analysis of antigens more closely associated with different maturational stages of B- and T-cell lineage has proven useful for the identification of biologically and clinically distinct entities in both B-cell precursor and T-lineage ALL. Immunophenotyping in about 2800 patients recruited for the German multicentre trials has shown that children and adults differ markedly in frequency distribution of immunological subgroups, with a higher adult incidence of immature B-cell precursor (i.e., pre-pre-B ALL) and T-lineage ALL immunophenotypes (i.e., pre-T ALL). Detailed immunological analyses using a broad panel of mAbs have recently documented typical ALL cases inappropriately expressing myeloid antigens (My+ ALL) as well as morphologically/cytochemically defined acute myeloid leukaemia (AML) with lymphoid-associated markers (Ly+ AML). Based on our own results and a critical review of published data, leukaemic blasts in 5-20% of ALL patients disclose My+ ALL, whereas a coexpression, mostly of T-cell-associated antigens, can be identified in 10-25% of AML cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Correlation of cytogenetic findings with clinical features in 18 patients with inv(3)(q21q26) or t(3;3)(q21;q26).

An inversion in the long arm of chromosome 3--inv(3)(q21q26)--or a translocation between both homologous chromosomes 3--t(3;3)(q21;q26)--is found specifically in myeloid neoplasias characterized by disturbances of thrombopoiesis and megakaryocyte development. Cytogenetic findings were correlated with clinical and hematological data in altogether 18 patients with acute nonlymphocytic leukemia (ANLL) and with inv(3) (13 patients) or t(3;3) (five patients), six of whom were male and 12 who were female. Chromosomal changes in addition to the 3q anomalies were demonstrated in 14 out of 18 patients, predominantly numerical and structural aberrations of chromosome 7 (12 cases) and/or abnormalities of 5q (five cases). Complex karyotype abnormalities were observed in six of 13 patients with inv(3), but in only one of five patients with t(3;3). In ten out of our 18 patients a preceding myelodysplastic syndrome (MDS) and/or exposure to mutagenic/carcinogenic agents had been established. In eight patients the morphology of ANLL blasts was immature (FAB subtype M1); in three patients ANLL-M4, and in two patients each ANLL-M5, M6, and M7 was diagnosed; in one patient with antecedent MDS the leukemic blasts were not classifiable according to the FAB criteria. A disturbed megakaryocyte development, characterized by an excess of micromegakaryocytes was observed in 14 patients, seven of them showed normal or elevated platelet counts as an unusual feature in patients with ANLL. The clinical course and outcome was extremely poor: 15 of 18 patients died within 10 months after the diagnosis of ANLL. Because of their missing response to conventional chemotherapy, patients with inv(3) or t(3;3) have to be estimated as at high risk. The characterization of genes affected by inv(3) or t(3;3) could help to elucidate molecular changes leading to impaired proliferation and differentiation of hematopoietic cells, also of the megakaryocytic lineage. Based on molecular genetic findings new therapeutical approaches could be designed.

Adult↗
PubMed1993

Selective targeting of human lymphokine-activated killer cells by CD3 monoclonal antibody against the interferon-inducible high-affinity Fc gamma RI receptor (CD64) on autologous acute myeloid leukemic blast cells.

The potential of the CD3 monoclonal antibody (MoAb) OKT3 to selectively target lymphokine-activated killer (LAK) cells and T-cell clones in vitro against autologous tumor cells was studied using material from patients with acute leukemias (19 acute myeloid leukemias [AML], and 3 acute lymphoblastic leukemias [ALL]). Cytotoxicity mediated by patient LAK cells against AML blasts, but not against ALL cells and autologous Epstein-Barr virus-transformed B cells, was enhanced 1.5-fold to 9.3-fold by OKT3 in all AML patients studied. The following findings suggest that the major target molecule on AML cells for OKT3-coated LAK cells is the high-affinity Fc receptor for IgG (Fc gamma RI; CD64): (1) susceptibility to killing by OKT3-coated effector LAK cells segregated with target cell expression of CD64; (2) preincubation of AML blasts with monomeric OKT3 (murine IgG2a), the Fc portion of which is known to have preferential binding affinity to CD64, resulted in lysis by autologous T cells that were not spontaneously cytotoxic; (3) OKT3-dependent increase in lysis of primary and relapsed AML cells by autologous T-cell clones correlated with the amount of target cell expression of CD64; (4) anti-leukemic cytotoxicity of OKT3-coated T cells could partially be inhibited by monomeric human Ig, the natural ligand of CD64; and (5) expression of CD64 (Fc gamma RI) on fresh AML cells could be increased by interferon-gamma (IFN-gamma) and IFN-alpha translating into further enhancement of lysis by autologous OKT3-coated LAK cells. Nonmalignant CD34+ cells sorted from peripheral blood were found to lack expression of CD64 and hence were not affected by OKT3-triggered T-cell targeting, as detected by colony formation assays. In conclusion, the in vitro data presented provide a rationale for the combined clinical use of recombinant interleukin-2, IFN-gamma, and low doses of CD3 MoAb to eliminate AML cells while sparing nonmalignant hematopoietic progenitor cells, for example, in the setting of purging procedures for autologous bone marrow transplantation.

Antigens, CD↗
PubMed1993

Recombinant human interleukin-4 inhibits growth of some human lung tumor cell lines in vitro and in vivo.

Cytokines play an important role in activating the immune system against malignant cells. One of these cytokines, interleukin-4 (IL-4) has entered clinical phase I trials because of its immunoregulatory potency. In the present study we report that recombinant human (rh) IL-4 has major direct antiproliferative effects on one human lung cancer cell line (CCL 185) in vitro as measured by a human tumor cloning assay (HTCA), tritiated thymidine uptake, and counting cell numbers and marginal activity in a second cell line (HTB 56) in the HTCA. This activity could be abolished by neutralizing antibody against rhIL-4. The biological response of the tumor cells to the cytokine is correlated with expression of receptors for human IL-4 on both the mRNA level and the protein level. The responsive cell line, CCL 185, secretes IL-6 after being incubated with rhIL-4. On the other hand, neutralizing antibodies against IL-6 showed no influence on the growth modulatory efficacy of rhIL-4 in this cell line. Furthermore, CCL 185 does not show detectable production of IL-1, tumor necrosis factor alpha or interferon gamma after incubation with rhIL-4. Thus, the response to rhIL-4 is not mediated through autocrine production of these cytokines triggered by rhIL-4. In a next series of experiments some of the cell lines were xenotransplanted to BALB/c nu/nu mice. Subsequently, the mice were treated for 12 days with two doses of 0.5 mg/m2 rhIL-4 or control vehicle subcutaneously per day. Treatment with rhIL-4 yielded a significant inhibition of tumor growth versus control in two of the non-small cell lung cancer cell lines being responsive in vitro (CCL 185, HTB 56). Histology of the tumors in both groups showed no marked infiltration of the tumors with murine hematopoietic and lymphocytic cells consistent with the species specificity of IL-4. In contrast, no tumor growth inhibition was found in the small cell lung cancer cell lines (HTB 119, HTB 120) being nonresponsive in vitro. We conclude that rhIL-4 has direct antiproliferative effects on the growth of some human non-small cell lung cancer cell lines in vitro and in vivo, which together with its regulatory effects on various effector cell populations makes this cytokine an interesting candidate for further investigation in experimental cancer treatment.

Animals↗
PubMed1993

[Late cardiac toxicity in Hodgkin's disease. A study with pulsed Doppler echocardiography].

49 patients (22 women, 27 men, mean age 43.7 [21-65] years) with Hodgkin's disease were examined by Doppler echocardiography a median of 5.37 (2-10) years after the end of chemotherapy (given according to the COPP/ABVD scheme, with or without mediastinal irradiation) for possible chronic changes in myocardium, pericardium or cardiac valves, as well as for any haemodynamic sequelae. Maximal and integrated early (E, Ei) and late (A, Ai) diastolic flow velocities and their ratio (E/A, Ei/Ai) were measured by pulsed Doppler over the mitral and tricuspid valves. Although on two-dimensional echo 21 patients (42.9%) were found to have valvar thickening, 19 (38.8%) pericardial thickening and 9 (18.4%) a reduced fibre shortening fraction, the Doppler indices were statistically not significantly different from those in 25 controls with normal hearts. These echocardiographic data of functional and morphological parameters indicate that there was no effect on various measurements of diastolic function after chemotherapy with or without mediastinal radiation. In successfully treated patients with Hodgkin's disease the described changes are of minor significance.

Adult↗