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Biomedical subjects

E Thiel

Publications and source records attributed to E Thiel.

At least 199 records · Page 11Linked to original sources

Synergistic antitumor interactions between newly synthesized ruthenium complexes and cytokines in human colon carcinoma cell lines.

The purpose of these studies was to assess the antiproliferative properties of newly synthesized, heterocyclic ruthenium complexes alone and in combination with cytokines (tumor necrosis factor-alpha, interferon alfa, beta, and gamma) against various human colon carcinoma cell lines. To determine whether any of these ruthenium compounds possesses antitumor activity and reveals synergistic interaction with cytokines six new ruthenium complexes were studied. All six compounds exerted dose-dependent antitumor effects in all colon cancer cell lines tested. The most effective compounds were trans-indazolium[tetrachloro(2H-indazole)ruthenate (III, N1)] and trans-indazolium[tetrachlorobis(1 H-indazole)ruthenate (III, N2)]. Interferon alfa, beta, and gamma as well as tumor necrosis factor-alpha exerted only minimal antiproliferative effects in colon carcinoma cell lines. The data were further analyzed to determine whether preincubation with cytokines altered sensitivity of the cells to synergistically potentiating growth-inhibitory effects. Although simultaneous incubation of ruthenium complexes and interferon did not result in synergistic or additive interactions, 24-hour preincubation with interferon alfa, beta, and gamma significantly enhanced antitumor activity. We conclude from these data that two of six newly synthesized ruthenium complexes possess antiproliferative activity against a panel of human colon carcinoma cell lines. Moreover, biological modulation with interferon using 24-hour preincubation resulted in synergistic interactions. We are planning a phase I trial, since antitumor activity of these ruthenium compounds has been demonstrated in vitro and in vivo, and toxicity as well as stability data are now available.

Carcinoma↗

GM-CSF-mediated proliferation induction improves the susceptibility of leukemia cells to lymphokine-activated killer cells.

Our studies on the susceptibility of fresh noncultured leukemia cells to interleukin-2 (IL-2)-induced lymphokine-activated killer (LAK) cells have shown that about two thirds of the leukemias are susceptible to the LAK-cell-mediated cytolysis. Analysis of 214 acute leukemias revealed considerable variation in the degree of cytotoxicity achieved. Cytolysis was substantially lower in fresh noncultured acute leukemia samples than in K562 and Daudi cell lines (mean Cr-release 21.0 +/- 16.0% versus 69.2 +/- 6.6% and 70.8 +/- 7.9%). Augmentation of susceptibility to LAK-cell lysis is desirable in connection with therapeutic application of IL-2-induced effector mechanisms. We observed a relationship between the LAK-cell susceptibility of leukemia cells and their spontaneous proliferation rate, which is significantly higher in LAK-cell-sensitive than in LAK-cell-resistant leukemias. It was therefore considered useful to examine the possibility of augmenting LAK-cell sensitivity by proliferation induction. These studies demonstrate that incubation of blast cells from acute myeloid leukemia (AML) and chronic myelogenous leukemia in myeloid blast crisis (CML-BC) with recombinant granulocyte-macrophage colony stimulating factor (GM-CSF) significantly augments LAK-cell susceptibility and that this is associated with an increased cell proliferation.

Cell Cycle↗

Detection of chimeric BCR-ABL genes in acute lymphoblastic leukaemia by the polymerase chain reaction.

Philadelphia chromosome-positive acute lymphoblastic leukaemia (ALL) is most common in adults and is associated with poor prognosis. Since karyotypic identification of the Philadelphia translocation has been hampered by technical difficulties, we used the polymerase chain reaction (PCR) to look for the BCR-ABL rearrangement in stored samples from a selected group of 314 German ALL patients. BCR-ABL transcripts were found in 77 of 179 adults and were restricted to those with B-precursor leukaemias. 55% of adult common ALL patients had BCR-ABL and its presence correlated with poor overall survival and remission duration. Of 135 children with common ALL, 5 (6%) primary cases and 8 (17%) with recurrent neoplasias were PCR-positive. We recommend prospective evaluation of BCR-ABL analysis with PCR in patients with a B-precursor leukaemia.

Adult↗

Ultrastructural demonstration of peroxidase expression in acute unclassified leukemias: correlation to immunophenotype and treatment outcome.

The lineage affinity of 57 cases of acute unclassified leukemias (AUL) was reevaluated by ultrastructural analysis of peroxidase expression (POEM) in combination with immunophenotyping and analysis of immunoglobulin gene configuration. Twenty-three cases of myeloid and three cases of megakaryocytic differentiation were identified by detection of ultrastructural myeloperoxidase (UMPO) and platelet peroxidase (UPPO). No significant correlation was noted between myeloid marker expression and POEM positivity, whereas presence of CD 19 or CD 24 antigen significantly correlated with POEM negativity (P = .001 and .023, respectively). Ig gene rearrangements including oligoclonal patterns were also recorded in 8 of 14 UMPO+ patients tested. Fourteen UMPO+ patients responded poorly to an ALL/AUL chemotherapy regimen with a low complete remission (CR) rate of 29% and a short median remission duration (MRD) of 5 months. The POEM- patients proved very heterogenous with respect to immunophenotype and Ig gene rearrangement. Seventeen of 21 patients tested had Ig gene rearrangements, including oligoclonal patterns. Combined data suggest that a proportion of these cases probably derive from a very immature lymphoid progenitor cell, particularly because 15 POEM- AUL patients showed a response to ALL/AUL chemotherapy comparable to that observed in patients with definitive acute lymphoblastic leukemia (ALL) (CR rate 80%, MRD 20 months). Thus, ultrastructural analysis of peroxidase expression can provide decisive prognostic information in AUL patients.

Acute Disease↗

Studies on the role of recombinant human erythropoietin in the growth regulation of human nonhematopoietic tumor cells in vitro.

Recombinant human (rh) erythropoietin (EPO) is attracting increasing interest as an agent for treating cancer-related anemia. Thus, we have tested the effects of rhEPO on the clonal growth of 22 different cell lines derived from a wide range of human solid tumors (head and neck 3, lung 2, breast 2, stomach 1, colorectal 3, hepatocellular 1, pancreas 1, ovary 1, choriocarcinoma 1, osteogenic sarcoma 1, glioblastoma 2, neuroblastoma 1, prostate 1, renal 2) in vitro. RhEPO (dose range 0.01-100 U/ml) caused no significant and reproducible stimulation of clonal growth as measured by a capillary modification of the human tumor cloning assay in agar in any of the cell lines tested. In particular, there was no sensitivity for rhEPO of those cell lines which were shown to be responsive to interleukin-3 and GM-CSF. On the other hand, there were no growth inhibitory effects of rhEPO on the cell lines of this study. Finally, neutralizing anti-human EPO antibody had no effect on the clonal growth of two kidney carcinoma cell lines, making autocrine growth regulation by hEPO in these lines unlikely.

Antibodies↗

Visceral leishmaniasis mimicking a flare of systemic lupus erythematosus.

Fever in systemic lupus erythematosus (SLE) may be caused by exacerbation of the disease itself or by infection. We report on a patient with a long standing history of SLE that was complicated by fever and pancytopenia with no splenomegaly. SLE disease activity was suspected because of an elevated DNA-antibody titer. The early positive response to corticoid therapy may have masked the underlying infection. Visceral leishmaniasis was diagnosed by a repeated bone marrow biopsy and serological testing.

Animals↗

Review of the incidence and clinical relevance of myeloid antigen-positive acute lymphoblastic leukemia.

An increasing number of papers document cases of acute leukemia in which individual blast cells co-express markers normally restricted to a single cell lineage. Numerous terms are used to refer to cases with unscheduled expression of lineage-foreign proteins; the best defined categories were hybrid acute leukemia and acute mixed-lineage leukemia. The incidence of phenotypically variant acute leukemia varies with the quality and quantity of parameters used and the stringency of the criteria employed for its definition. Considerable interest has focused on acute lymphoblastic leukemia (ALL) cells expressing one or several myeloid lineage-associated antigens (My+ ALL), CD13, CD14, CD15, CD33, and CDw65. Owing to legitimate and cryptic expression on lymphoid cells, CD11b and CD15 reagents may not be considered as specific indicators of myeloid differentiation. The reported incidence ranged from 5 to 46% in 14 studies on My+ ALL, totalling 3817 patients. Several detailed reports documented a higher incidence of My+ ALL in adults (realistically in the range 10-20%) than in children (5-10%) and in B-lineage ALL as opposed to T-lineage ALL. My+ ALL cases are more likely to display unique cytogenetic [t(9;22), 11q23, 14q32] features than My-neg ALL. There appears to be no predominant expression of a single myeloid-associated antigen among those analyzed. As the morphological diagnosis of a leukemia subtype is often imprecise, some T-neg B-neg My+ ALL cases might actually contain FAB AML-M0 populations. While the expression of myeloid-associated antigens has no apparent prognostic significance in the majority of childhood ALL subtypes, in adults myeloid antigens seem to identify a high risk group of ALL patients with a poorer response to standard ALL therapy.

Adult↗

Prognostic implication of ecto-5'-nucleotidase activity in acute lymphoblastic leukemia.

Ecto-5'-nucleotidase (5'-N) activity was determined in 191 patients (71 children and 120 adults) with acute leukemia. Elevated values for 5'-N were registered in common acute lymphoblastic leukemia (ALL), but blast cells of T-cell ALL (T-ALL) and common ALL antigen-negative non-T-ALL had low enzyme activity comparable with the values of acute non-lymphocytic leukemia. Dependence of remission duration on 5'-N activity was analyzed in 74 adults with ALL, treated similarly in a prospective multicenter trial. The remission curves for ALL patients with 5'-N activity lower than 10 nmol/h x 10(6) cells were substantially and significantly better than those of patients with high activity (greater than 10 nmol/h x 10(6) cells). This difference was also evident in the immunologic subclass common ALL. Statistical evaluation showed that an interaction between immunologic subtype of the blast cells and their 5'-N activity had prognostic significance for remission duration. In addition to the independent factor, initial age, this interaction was also prognostic for survival.

5'-Nucleotidase↗

Mitoxantrone/high-dose Ara-C and recombinant human GM-CSF in the treatment of refractory non-Hodgkin's lymphoma. A pilot study.

Previous study has shown that the combination of mitoxantrone (Novantrone, NO) and Ara-C (AC) (NOAC) was active in refractory non-Hodgkin's lymphoma (NHL) but myelosuppression was dose-limiting. In a pilot study, we investigated the effects of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) after NOAC chemotherapy in patients with refractory NHL. NO was applied at a dosage of 10 mg/m2/day on days 2 and 3 and AC at 3 g/m2/12h on days 1 and 2. RhGM-CSF was administered at 250 ug/m2/day as a continuous i.v. infusion from day 6 until the neutrophils were greater than 3.0/nl for 3 consecutive days. Twenty-three patients from five of the nine participating centers were treated with NOAC chemotherapy plus rhGM-CSF, whereas 14 patients from the other four centers received chemotherapy alone. With rhGM-CSF, the median duration of severe neutropenia (less than 0.5/nl) after NOAC was 8 days versus a median of 13 days without rhGM-CSF (P = 0.0058), and that of thrombocytopenia (less than 20.0/nl), 3 days versus 7 days (P greater than 0.4, NS). The rates of infections and stomatitis were 25% and 17%, respectively, for patients treated with rhGM-CSF as compared to 53% (P = 0.0547, NS) and 60% (P = 0.0078), respectively, without rhGM-CSF. The following side effects were associated with the administration of rhGM-CSF: pleural and/or pericardial effusions in five patients, thrombosis in two patients, bone pain in two patients, and respiratory distress syndrome in one patient. A complete remission was achieved in nine of the 23 patients treated with NOAC plus rhGM-CSF, and in two of the 14 patients treated with chemotherapy alone. The median survival of patients treated with rhGM-CSF was not reached at 400 days and seemed to be longer than that of patients treated with chemotherapy alone (median, 109 days; P = 0.036). RhGM-CSF after chemotherapy can be applied safely to patients with NHL, shorten the period of severe cytopenia, reduce the rates of stomatitis, and did not seem to cause adverse effects on response.

Adolescent↗

[Interferon alfa-2B in chronic lymphatic leukemia of the B-cell type].

In a clinical phase II study nine patients (five men and four women; mean age 48 [42-58] years) in an early stage of chronic lymphatic leukaemia (CLL) of the B-cell type were treated with recombinant alpha-2b interferon (IFN alpha-2b), initially at a dosage of 5 mega units subcutaneously three times weekly, but in some cases reduced to 2.5 or raised to 10 mega units. Duration of treatment has been 15-36 months. Through-flow cytometry in seven patients demonstrated a definite fall in circulating B1-positive lymphocytes. Lasting partial remission (duration of 106-134 weeks) was achieved in four patients, in a further four the condition remained stable. A recurrence was noted in the patient with the initially highest lymphocyte count (52,000/microliters) after 28 weeks, control being achieved only after 64 weeks of chemotherapy. Side effects were flu'-like symptoms and (in two instances) depression. In three patients there was a clear rise in serum immunoglobulin concentrations as sign of IFN alpha-2b-induced increased immune response, while in four HLA-DR expression on monocytes was doubled. It is concluded that early treatment of CLL with IFN alpha-2b may delay the onset of necessary chemotherapy, any antibody-deficiency may be improved and survival time may ultimately be lengthened.

Adult↗