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E Thiel

Publications and source records attributed to E Thiel.

At least 55 records · Page 3Linked to original sources
PubMed2002

CSF evaluation in primary CNS lymphoma patients by PCR of the CDR III IgH genes.

BACKGROUND: Cytologic evaluation of CSF does not consistently detect malignant cells in patients with primary CNS lymphoma (PCNSL). The potentially more sensitive molecular assessment of monoclonality has not been shown in CSF samples. METHODS: The authors studied nested PCR of the complementary determining region III (CDR III) on 76 CSF specimens of patients with PCNSL. Patients with systemic disseminated B-cell non-Hodgkin's lymphoma (n = 17) and 17 patients with no history of lymphoma were compared. PCR products were evaluated by automated fluorescent fragment analysis (ALF). RESULTS: In 68 patients with PCNSL, the authors analyzed the first obtained CSF sample. Nevertheless, 60 patients were taking corticosteroids. In 16 PCNSL samples, amplifiable DNA was not yielded. Taking into account that at least two independent assays have to be performed, CDR III PCR consistently revealed monoclonal products in eight PCNSL and polyclonal results in 52 PCNSL specimens. CDR III PCR detected no monoclonal PCR products in patients without history of lymphoma. In 10 patients with PCNSL, the PCR result and the CSF cytology were discordant. Concerning therapeutic impact, leptomeningeal tumor spread did not predict tumor response in this group of patients with PCNSL. CONCLUSIONS: This study performed CDR III PCR as a routine diagnostic technique applicable even on CSF samples with low cell counts. These data present low incidence of leptomeningeal involvement in this subset of pretreated PCNSL patients. Because the CSF evaluation did not predict outcome in our patients, further analysis in patients with PCNSL should focus on CSF samples that are obtained very early after diagnosis.

Adult↗
PubMed2002

Response to topotecan of symptomatic brain metastases of small-cell lung cancer also after whole-brain irradiation. a multicentre phase II study.

The purpose of this multicentre phase II study was to evaluate the efficacy and toxicity of topotecan in pretreated patients with small-cell lung cancer (SCLC) who relapsed with symptomatic brain metastases. 30 patients with a median age of 62 years were entered into the study. 22 patients received the initially planned dose of 1.5 mg/m(2) topotecan as a 30-min intravenous (i.v.) infusion for 5 consecutive days every 3 weeks. Due to the observed thrombocytopenia, the dose was reduced to 1.25 mg/m(2) in the last 8 patients. All 30 patients were pretreated with chemotherapy: 14 with one and 16 with at least two protocols. 8 patients had prior whole-brain iradiation (WBI): 7 in the prophylactic and 1 in the palliative setting. Concomitant systemic metastases were recorded in 24 patients at the time of brain relapse. Cerebral metastases responded in 33% of patients (10/30; three complete responses (CR) and seven partial responses (PR)). Noteworthy is the fact that response was achieved in 4 of 8 patients pretreated by WBI (3 in prophylactic and 1 in palliative setting). The systemic response rate was 29% (7/24). Median time to progression was 3.1 months (range 0.25-14.2+ months), median survival from the beginning of this study was 3.6 months (range 0.25-14.2+ months). Therapy was generally well tolerated, with myelotoxicity being the most common adverse event. Grade 3 leucocytopenia according to the Common Toxicity Criteria (CTC) occurred in 28% (23/83) of the courses and grade 4 in 22% (18/83). Grade 3 thrombocytopenia was observed in 17% of the courses (14/83) and grade 4 in 11% (9/83). 17% of patients (5/30) had a documented grade 3 infection. These results using topotecan are promising in heavily pretreated patients with SCLC brain metastases and merit further evaluation.

Adult↗
PubMed2002

Quantitative real-time RT-PCR detects elevated Wilms tumor gene (WT1) expression in autologous blood stem cell preparations (PBSCs) from acute myeloid leukemia (AML) patients indicating contamination with leukemic blasts.

High-dose chemotherapy with subsequent autologous stem cell transplantation is believed to be of therapeutic benefit in patients with acute myeloid leukemia (AML), especially when no allogeneic bone marrow donor is available. One of the main risks is contamination of the stem cell preparations with leukemic blasts, which may account for a higher relapse rate compared to allogeneic bone marrow transplantation. Since overexpression of WT1 is common in leukemic blasts, we investigated, whether PBSCs from AML patients express WT1 at a higher level as compared to patients with solid cancers. PBSCs of seven patients with AML and of five patients with solid cancers were investigated for WT1 expression. Total WT1 copy count was determined in a standardized quantitative real time RT-PCR. WT1 expression was found in all AML PBSCs with an average copy number of 49.99 +/- 61.09. In solid cancers WT1 expression was statistically significantly lower with a copy number of 3.51 +/- 1.92. In AML patients with sustained complete remission we found a nearly significantly lower WT1 expression than in patients who relapsed within the first year after stem cell transplantation. Our data show a higher WT1 expression in PBSCs of AML patients compared to patients with solid cancers. This finding might indicate a contamination with leukemic blasts. Quantification of WT1 in PBSCs might therefore be useful to estimate the risk of relapse after autologous stem cell transplantation in AML patients.

Acute Disease↗
PubMed2002

Dual effects of arsenic trioxide (As2O3) on non-acute promyelocytic leukaemia myeloid cell lines: induction of apoptosis and inhibition of proliferation.

Clinical efficacy of As2O3 has been shown in patients with relapsed acute promyelocytic leukaemia (APL). There is evidence that the effects of As2O3 are not restricted to events specific for APL. As2O3 might target mechanisms involved in the pathogenesis of other malignancies. We assessed susceptibility to induction of apoptosis by As2O3 and cytostatics in 22 myeloid and non-myeloid malignant cell lines. As2O3 was used in concentrations of 0.01-10 micromol/l. Cell lines displayed different kinetics of response and different sensitivity to As2O3. The minimum concentration of As2O3 for induction of apoptosis was 0.1 micromol/l. High concentrations of As2O3 (5 micromol/l) induced apoptosis in a large proportion of cells in all cell lines tested. Low (1 micromol/l As2O3) concentrations induced apoptosis in NB-4, HL-60, U-937, CEM, HL-60, KG-1a, PBL-985, ML-2 and MV-4-11, but not in HEL, K-562, KG-1 and Jurkat up to 35 d of incubation. However, the non-apoptotic population of 1 micromol/l As2O3-treated HEL, K-562, K-562 (0.02), K-562(0.1) and Jurkat showed reduced proliferation. CEM as well as its' multidrug-resistant derivatives were sensitive to 1 micromol/l As2O3. In summary, these data demonstrate that As2O3-induced apoptosis is not restricted to cell lines with t(15;17). Apoptosis was induced in vitro by As2O3 concentrations that are achievable in vivo after infusion of well-tolerated As2O3 doses. Thus, As2O3 might be a suitable therapeutic agent for malignancies other than APL provided the adequate dose and duration of As2O3 treatment are used.

Antineoplastic Agents↗
PubMed2002

Flow cytometric CD34+ determination in stem cell transplantation: before or after cryopreservation of grafts?

Various attempts have been made to standardize and improve the reproducibility of flow cytometric determination of CD34+ hematopoietic progenitor cells. It is still not clear, however, whether the quantification of CD34+ cells in a stem cell graft should be done before or after cryopreservation. To address this issue, we investigated 78 unselected and 32 immunomagnetically selected autologous and allogeneic leukapheresis products (LA) before and after cryopreservation using pilot vials. Cell numbers were quantified within a Neubauer chamber, and CD34+ content was determined by flow cytometry; propidium iodide staining was used to exclude dead cells from analysis. Before freezing, the mean viable CD34 cell content in the unselected samples was 1.22% and increased after thawing to a mean of 2.16% of viable cells. Taking into account cell loss and cell death, the overall recovery of viable cells was 64.5%; all CD34+ cells could be recovered. Mean purity in the CD34-selected cell fraction was 85% (48-97) before and 91.3% (67-99) after thawing. The number of viable cells was 86.8% before and 86.1% after freezing with a 93.9% recovery of total cells. This leads to a mean 93.7% (SD +/- 23.1) recovery of viable cells and 100% (SD +/- 22.3) recovery of viable CD34+ cells. There was no significant difference in tolerance to freeze/thaw stress between cells from heavily pretreated autologous patients and healthy allogeneic donors. Our data show that freezing significantly increases the percentage of CD34(+) cells in unmanipulated LA, probably due to the death of granulocytes and mononuclear cells (MNCs). Nevertheless, the overall number of viable CD34+ cells in unselected as well as selected samples remains unchanged. Thus, CD34 data from different laboratories, for example, within multicenter trials, should be comparable independent of the different time points of acquisition.

Antigens, CD34↗
PubMed2002

Successful treatment of extracranially metastasized pineal gland germinoma with high-dose methotrexate.

Germinoma of the pineal gland is a rare disease usually confined to the brain which responds well to radiotherapy. Spinal seeding occurs in approximately 4% of cases and distant metastases are extremely rare. We report on a 27-year-old female with an intracranially metastasized pineal gland germinoma, meningeal carcinomatosis and distant bone metastases. Treatment was initiated with intrathecal methotrexate (MTX) and continued with high-dose intravenous MTX. The therapy was very well tolerated apart from reversible hepatic toxicity requiring a dose reduction. The patient was in complete remission after three courses followed by two consolidation cycles; the patient has now been in continuous complete remission for more than 22 months. This is the first report to show that MTX is a potent drug in treating pineal gland germinoma. Long-term side effects of radiotherapy such as reduced mental function or hypopituitarism can probably be avoided. Single-agent high-dose MTX may provide high efficacy with limited adverse effects, especially at a more advanced tumor stage with spinal seeding and extracranial disease.

Adult↗
PubMed2001

Targeting of a B7-1 (CD80) immunoglobulin G fusion protein to acute myeloid leukemia blasts increases their costimulatory activity for autologous remission T cells.

Transfection of tumor cells with the gene encoding the costimulatory molecule B7-1 (CD80), the ligand for CD28 and cytotoxic T lymphocye antigen-4 on T cells, has been shown to result in potent T-cell-mediated antitumor immunity. As an alternative approach, this study analyzed the costimulatory capacity of a human B7-1 immunoglobulin G (IgG) fusion protein targeted to the cell membrane of human acute myeloid leukemia (AML) blasts. Flow cytometric analysis revealed a low constitutive expression of B7-1 on human AML blasts (on average, 3.0 +/- 4.3%; n = 50). In contrast, the expression of B7-2 (CD86) was highly heterogeneous and higher in AML blasts of French-American-British classification types M4 and M5 (P <.0001). The B7-1 IgG fusion protein used in this study efficiently costimulated the proliferation of resting and preactivated T cells when immobilized on plastic. After preincubation with B7-1 IgG, specific binding of the fusion protein to the high-affinity Fcgammareceptor I (CD64) on leukemic cells was demonstrated and was found to increase the proliferation of both allogeneic and autologous T cells in costimulation experiments. Furthermore, targeting of B7-1 IgG to the tumor membrane resulted in increased proliferation of autologous remission T cells and had the potential to generate an enhanced redirected cytotoxic T-cell response against autologous AML blasts. In summary, the targeting of B7-1 IgG fusion protein described in this study represents a strategy alternative to gene therapy to restore the expression of the costimulatory molecule B7-1 on human AML blasts, thereby enhancing their immunogenicity for autologous T cells. This new approach may have implications for T-cell-mediated immunotherapy in AML.

B7-1 Antigen↗
PubMed2001

Flow cytometric determination of intracellular or secreted IFNgamma for the quantification of antigen reactive T cells.

The detection of antigen-induced IFNgamma secretion at the single cell level can be used to identify and enumerate antigen-reactive T cells from peripheral blood. This study was performed to analyze the suitability of T cell enumeration by flow cytometry in comparison with the ELISPOT assay. Peripheral blood mononuclear cell (PBMC) samples from six HLA-A2+ healthy subjects were analysed for the frequency of influenza-reactive CD8+ T cells by flow cytometry detecting either intracellular IFNgamma (IC-FC) or secreted IFNgamma (S-FC). All samples were also analysed by IFNgamma ELISPOT assay. The frequency of influenza peptide-reactive T cells determined by IC-FC was 0.01 to 0.34% of CD8+ T cells and by ELISPOT assay 0.02 to 0.23% of CD8+ T cells (n=6 subjects) with a high inter-assay reproducibility and a close correlation between the assays (r=0.77, P<0.001). Little or no IFNgamma production was observed in unstimulated PBMC samples using either the IC-FC or the ELISPOT assay. In contrast, using S-FC large numbers of IFNgamma-secreting CD8+ T cells (0.37% to 5.55%, n=6 subjects) were detected in unstimulated PBMC. The frequency of influenza-reactive CD8+ T cells (0.57-5.19%, n=6 subjects) determined by S-FC did not correlate with the values from the IC-FC or ELISPOT assays. This comparative study shows the suitability of the determination of frequencies of antigen reactive T cells in PBMC by IC-FC. The advantage of IC-FC is the possibility to phenotype simultaneously antigen-reactive T cells.

Antigens↗
PubMed2001

Application of the IFN-gamma ELISPOT assay to quantify T cell responses against proteins.

The ELISPOT assay has been established for the direct ex vivo quantification of peptide-reactive T lymphocytes from peripheral blood mononuclear cells (PBMC). In this report we studied the ELISPOT assay conditions for the detection of T cell responses against protein antigens including Tetanus toxoid (TT), purified-protein-derivative (PPD) and a synthetic 30 mer peptide derived from influenza matrix protein (IMP) containing the HLA-A*0201-restricted 9 mer peptide epitope GILGFVFTL as a model for a viral protein. We found several aspects to be crucial for a sensitive detection of T cell responses against proteins including a pellet preincubation step and the monocyte concentration. Using optimized assay conditions specific CD4+ T cell responses against TT and PPD as well as CD8+ T cell responses against IMP can be quantified directly ex vivo from peripheral blood mononuclear cells.

Amino Acid Sequence↗
PubMed2001

Neurofilament-immunoreactive neurons are not selectively vulnerable in Alzheimer's disease.

Abnormal neurofilament protein distribution and phosphorylation contributes to the cytoskeletal pathology of Alzheimer's disease. Anatomical studies suggest that cortical neurons immunoreactive for nonphosphorylated 200-kDa neurofilament are most vulnerable. We repeated these studies in formalin-fixed temporal lobe tissue from five Alzheimer's disease cases with tissue volume loss compared to five controls without tissue loss. Immunohistochemistry for nonphosphorylated and phosphorylated forms of the neurofilament protein was counterstained for Nissl substance and immuno-positive and -negative pyramidal neurons quantified using areal fraction counts. Compared with controls, cases with Alzheimer's disease had similar numbers of neurons expressing the nonphosphorylated neurofilament protein, suggesting these neurons are largely spared by the disease process. In Alzheimer's disease there was a significant increase in neurons containing phosphorylated neurofilament and tau proteins and a decrease in neurons devoid of neurofilament protein. Our results challenge the theory that neurons containing 200 kDa neurofilament are selectively vulnerable in Alzheimer's disease.

Aged↗
PubMed2001

Nested quantitative real time PCR for detection of occult tumor cells.

Quantification of tumor mRNA markers expressed by occult circulating tumor cells may be of prognostic value in a variety of neoplasms and disease stages. We therefore developed a novel real time nested polymerase chain reaction (PCR) assay to quantify rare transcripts using the light cycler system. Tyrosinase mRNA expressed by melanocytes and melanoma cells was used as a model. Ten-milliliter samples of ethylenediaminetetra-acetate (EDTA) blood from healthy volunteers were spiked with 10-10(4) RVH melanoma cells. Following RNA extraction and cDNA synthesis, a nested PCR with specific primers was performed. Resonance energy transfer between fluorescently labeled hybridization probes specific for the amplified portion of the tyrosinase transcript allowed continuous monitoring of the second round of PCR. The number of preamplification cycles in the first round was varied between 20 and 35. Our results show that nested PCR revealed quantitative data, regardless of the number of cycles used in the first round. The range of real time data can span four logs of target mRNA concentrations (1-10(3) tumor cells/ml of blood) and the x-intercepts of the log phases were always consistent with the amount of transcripts in the sample. These experiments indicate that nested PCR, which is much more sensitive than single-round PCR, is a useful tool for the quantification of rare transcripts--a result with important implications for the study of minimal residual disease. The assay is currently being adapted for other tumor types including leukemias as well as other solid tumors.

DNA Primers↗
PubMed2001

5. Report on workshop: Primary CNS lymphoma.

The increase in primary CNS lymphoma (PCNSL) has resulted in a growing interest in this disease. Despite efforts to optimize the management of PCNSL, several therapeutic questions remain unanswered. Due to methodological pitfalls in the clinical trials published thus far, particulary their uni- or oligocenter setting and the small number of patients, it has been difficult to draw definitive conclusions. Future efforts should concentrate on identifying optimal chemotherapy combinations, evaluating the efficacy of modern therapy options such as high-dose chemotherapy supported by autologous blood stem cell transplantation, and clarifying the impact of radiotherapy delay in complete responders to chemotherapy. Standardized neuropsychological testing and quality-of-life assessment are indispensable in future PCNSL trials. Important questions regarding management of PCNSL should be preferably addressed in large multicenter prospective randomized trials.

Antineoplastic Agents↗
PubMed2001

Molecular genetics in acute and chronic leukemias.

The application of molecular biological techniques in malignant hematologic diseases, particularly leukemias, has led to a rapid increase in knowledge and a deeper insight into the pathobiology of these diseases. Leukemia is a very heterogeneous disease on the molecular level. Clonal chromosomal abnormalities can be found in the vast majority of cases. A broader understanding of the underlying molecular changes has enabled the development of risk-adapted therapy regimens with improved outcome. One example is the application of molecular genetic techniques for detecting small numbers of leukemia cells after therapy ("minimal residual disease"). This allows the early preclinical recognition and prevention of relapse. This study gives a short overview of the current status of molecular genetics in human leukemias and its implications for the therapy and prognosis of these diseases. The following topics are covered: generation of oncogenic fusion genes or dysregulation of protooncogenes by chromosomal translocations, detection of minimal residual disease based on clonally rearranged immunoglobulin or T-cell receptor genes or on leukemia-specific fusion genes, monitoring bone marrow chimerism after allogeneic transplantation by molecular genetic techniques, and the role of oncogenic herpesviruses and retroviruses in human hematologic malignancies.

Acute Disease↗
PubMed2001

Comparison of ethidium bromide-stained agarose gel electrophoresis and automated fragment analysis for evaluation of IgH gene products.

In acute lymphoblastic leukemia (ALL) patients, automated fluorescence fragment analysis (ALF) has been reported to improve the monoclonality detection rate of immunoglobulin heavy chain genes (IgH) polymerase chain reaction (PCR) analysis. This study performed complementary determining region (CDR) I and III PCR on samples from 135 patients with B-cell neoplasias and 25 healthy controls. The value of ALF was investigated in comparison to the widely used ethidium bromide (ETB)-stained agarose gels (AGGE). ETB-stained AGGE detected monoclonal CDR III PCR products in 53/72 ALL, in 22/34 non-Hodgkin's lymphoma (NHL), 13/22 multiple myeloma (MM), and 2/7 monoclonal gammopathies (MGUS). ALF identified monoclonal CDR III amplificates in 55/72 ALL, 23/34 B-NHL, 14/22 MM, and 2/7 MGUS. AGGE achieved clonal CDR I PCR results in 30/64 samples, while ALF detected 34 clonal CDR I product patterns. Taking together, ETB-stained AGGE revealed monoclonality in 120/199 PCR products versus 129/199 by ALF. Compared with AGGE and ETB-staining, ALF offers a slightly increased sensitivity and can be recommended for the evaluation of difficult samples.

DNA, Neoplasm↗
PubMed2001

Cyclophosphamide, adriamycin and dexamethasone (CAD) is a highly effective therapy for patients with advanced multiple myeloma.

BACKGROUND: Patients with advanced multiple myeloma (stage III or progressive myeloma) received the CAD protocol every three weeks: cyclophosphamide 200 mg/m2 i.v./orally days 1-4, adriamycin 30 mg/m2 i.v. on day 1 and dexamethasone 40 mg p.o. days 1-4. PATIENTS AND METHODS: Forty-six patients with a median age of sixty years (range 34-84 years) were enrolled. According to Durie-Salmon 44 patients were in stage III, 2 in stage II; 6 patients had renal insufficiency (stage B). Twenty-three patients were pre-treated at least with melphalane/prednisone. RESULTS: Remission rates were as follows: complete remission 4%, partial remission 70%, minimal change 11%, no change 11%, progressive disease 4%. After an observation time of 14 months the median progression free interval for 33 patients not treated with subsequent high-dose chemotherapy with stem-cell support was more than 14 months. Overall, treatment was well tolerated. After 209 cycles given febrile neutropenia occurred in 11% of cycles including one fatal outcome. Neutropenia or thrombocytopenia grade 3-4 WHO was recorded in 18% and 6% of the cycles, respectively. CONCLUSIONS: This study shows that CAD is an effective regimen with an overall remission rate of 74%. The CAD protocol should be further evaluated in prospective trials.

Administration, Oral↗
PubMed2001

Testicular germ cell tumor with rhabdomyosarcoma successfully treated by disease-adapted chemotherapy including high-dose chemotherapy: case report and review of the literature.

Treatment and prognosis have not been well characterized in germ cell tumors (GCT) with a malignant nongerm cell component. Patients with a mediastinal tumor, neural or rhabdomyosarcomatous differentiation and distant metastases have the poorest prognosis. We report a rare case of mixed GCT composed of seminoma, teratoma and rhabdomyosarcoma with the rhabdomyosarcomatous component metastasized into the liver and bone marrow (BM) causing hypercalcemia. The patient was treated with differentiation-tailored chemotherapy (CHT) including a disease-adapted high-dose (HD) CHT regimen with purified autologous PBSCT (APBSCT) and pamidronate. To date, remission has lasted for 4 years. Tumor-adapted CHT including HD-CHT with APBSCT can induce long term remissions in high-risk patients with transformed GCT. A review of the literature is given.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

Prospective BCR-ABL analysis by polymerase chain reaction (RT-PCR) in adult acute B-lineage lymphoblastic leukemia: reliability of RT-nested-PCR and comparison to cytogenetic data.

The reliability of routine BCR-ABL RT-nested-PCR was evaluated in 1453 B-lineage ALL or hybrid leukemia at initial diagnosis by RT-nested-PCR. All BCR-ABL-positive (n = 642) and 176 BCR-ABL-negative samples underwent a second RT-PCR. In 518 patients, karyotyping and/or FISH was compared to the BCR-ABL status. The second RT-PCR revealed in 155/642 initially positive samples a divergent result (153 BCR-ABL-negative, two other transcripts) that in most cases turned out to be caused by contaminations in the first RT-nested-PCR. Confirmatory RT-PCR detected 2/176 false negative first RT-nested-PCR results. Thirty-nine specimens remained ambiguous despite different RT-PCR approaches. As far as cytogenetic evaluation and FISH is available (n = 23), the majority but not all patients with an ambiguous RT-PCR result were Ph-negative (n = 18). RT-nested-PCR and cytogenetics yielded in 346 of 383 evaluable samples a concordant result. Differing results are given and account in part to the lower sensitivity of karyotyping. Taken together, confirmed RT-PCR detected BCR-ABL fusion transcripts consistently in 487 out of 1453 ALL samples (c-ALL: 43%, pre-B ALL: 34%, pro-B ALL: 5%, B-ALL: 0%, hybrid leukemia: 5/11). Since false positive initial RT-nested-PCR data were frequent, either confirmatory second RT-PCR or FISH analysis is warranted to guarantee sensitive and reliable results of utmost clinical relevance.

Adult↗