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Biomedical subjects

E Thiel

Publications and source records attributed to E Thiel.

At least 19 recordsLinked to original sources

Lack of therapeutic effects of platelet activating factor antagonists in WEHI-3B leukemia, human xenotransplanted colorectal and lung cancer and Lewis-lung tumor in vivo.

Four new antagonists of platelet activating factor (PAF) from two different chemical classes (imidazoisoquinolines: SDZ 62-434, SDZ 63-135, SDZ 62-759; imidazopiperidines: SDZ 62-293) were tested for in vivo therapeutic activity in various tumor models including the murine myelomonocytic leukemia WEHl-3B, xenografts of human colon (HTB 38) and lung (HTB 119) cancer cell lines and the murine Lewis-lung tumor. After intraperitoneal (i.p.) injection of 1 x 10(3), 5 x 10(3) and 1 x 10(4) WEHl-3B cells into Balb/c mice, the drugs were given per os (p.o.) or i.p. over 6-14 days. Drug doses were pushed to exceed the lethal dose for 10% of the animals (LD10) and ranged from 1 to 100 mg/kg daily for p.o. treatment and from 1 to 75 mg/kg daily for i.p. treatment. In the xenotransplants and the Lewis-lung tumor experiments, PAF antagonists were given i.p. to nude Balb/c and C57 Black mice after intracutaneous (i.c.) tumor cell inoculation. None of the four compounds induced reproducible prolongation of life span, significant numbers of long term survivors, reduction of tumor size, or delay of tumor growth in any of the therapeutic models. Oral SDZ 62-759 had some activity in experiments in which there was slow WEHl-38 tumor growth in the controls. Toxicity of equivalent drugs doses was higher in the i.p. than in the p.o. schedules.

Animals

Recombinant human stem cell factor stimulates growth of a human glioblastoma cell line expressing c-kit protooncogene.

The growth of a panel of eight different human glioblastoma cell lines was examined in a human tumor cloning assay in agar, a tritiated thymidine uptake assay, and by counting cell numbers, in cultures performed in the absence or presence of increasing concentrations (1 to 100 ng/ml) of recombinant human stem cell factor (SCF). Growth of 7 of 8 cell lines was not significantly and reproducibly affected by recombinant human SCF. However, growth of the CRL 1620 cell line could be stimulated up to 5-fold by the cytokine. In contrast to the other cell lines investigated, CRL 1620 expressed the c-kit protooncogene assessed on the mRNA and protein level. Furthermore, SCF-induced proliferation of CRL 1620 cells was sensitive to the tyrosine kinase inhibitor erbstatin. Our data suggest that SCF can be operative in growth modulation of malignant cells outside the hematopoietic system, and this finding should be further studied for its possible clinical implications.

Cell Division

Cytotoxicity of interleukin 2-induced lymphokine-activated killer (LAK) cells against human leukemia and augmentation of killing by interferons and tumor necrosis factor.

Adoptive immunotherapy with interleukin 2-induced lymphokine-activated killer (LAK) cells or tumor-infiltrating lymphocytes (TIL) and the induction of anti-tumor responses by IL-2 alone having proven to be promising approaches in cancer therapy. The present study investigated the cytotoxicity of LAK cells towards human leukemia cells. LAK cells were generated by culturing peripheral blood mononuclear cells from normal donors for six days in the presence of recombinant interleukin 2 (IL-2). Cytotoxicity was evaluated using a standard 4-h chromium-release assay. A significant lysis of fresh uncultured leukemia cells by IL-2-activated killer cells could be detected in 77 of 150 leukemias examined. The mean Cr-release was 35.7 +/- 12.9% in the LAK cell-sensitive vs 9.9 +/- 5.9% in the resistant leukemias. With a view to the therapeutic utilization of the LAK-cell system, we attempted to improve the efficiency of its cytotoxic mechanisms. Combined application of IL-2 and interferon-alpha, interferon-gamma, or tumor necrosis factor-alpha in cultures for generation of activated killer cells significantly improved the effectiveness of cytotoxic mechanisms. Our results suggest that the performance of adoptive immunotherapy with ex vivo-activated LAK cells and the in vivo induction of cytotoxic immune responses by IL-2 alone or combined with different lymphokines or cytokines may be of value in treating human leukemia, especially when the tumor burden is low, e.g. during maintenance therapy or after bone marrow transplantation to eliminate minimal residual disease or in early relapse.

Cytokines

Effect of interleukin-3 and granulocyte-macrophage colony-stimulating factor on growth of xenotransplanted human tumour cell lines in nude mice.

The clonal growth of cell lines from some human solid tumours can be stimulated by haematopoietic growth factors such as recombinant human (rh) interleukin-3 (IL-3) and rh granulocyte-macrophage colony-stimulating factor (GM-CSF) in vitro. Among these cell lines are the human colorectal adenocarcinoma cell line HTB 38 and the human small-cell lung cancer cell line HTB 119. Here we report on a series of experiments studying the influence of subcutaneously administered rhIL-3 and rhGM-CSF on the in vivo growth of HTB 38 and HTB 119 cell lines as xenografts in athymic nu/nu BALB/c mice. Beginning 1 day after transplantation of the tumour the cytokines were administered daily for 20 days as a subcutaneous bolus distant from the tumour lesion at dose levels up to 1 mg/m2/day. The cytokines caused no significant and reproducible growth modulation of the tumours in vivo.

Adenocarcinoma

Long-term gonadal dysfunction and its impact on bone mineralization in patients following COPP/ABVD chemotherapy for Hodgkin's disease.

Only limited data is currently available on long-term gonadal toxicity and its impact on bone mineralization in men and women treated for Hodgkin's disease. The present study was therefore conducted to evaluate gonadal toxicity and bone loss in 49 patients with Hodgkin's disease 2-10 (median 5.37) years after chemotherapy. Most patients were treated with the COPP/ABVD regimen +/- irradiation according to the protocols of the German Hodgkin Study Group. Blood samples were tested for gonadotropins (FSH, LH), gonadal steroids, parathyroid hormone, osteocalcin, and calcitonin. Bone mineral density was measured using single- and dual-energy quantitative computed tomography as well as single-photon absorptiometry. FSH serum levels were significantly increased in 21/27 (80%) men demonstrating germ-cell aplasia. 13/15 (86%) men showed azoospermia after the COPP/ABVD regimen. In contrast, testosterone levels were within normal limits in all men tested, suggesting normal Leydig-cell function. 17/22 (77%) women exhibited increased FSH and LH levels, indicating premature ovarian failure. Women with therapy-induced ovarian failure had a significantly lower trabecular (98 +/- 34) and cortical (292 +/- 48 mg/cm3) spinal bone density than those with normal ovarian function. Men showed no evidence of bone loss after therapy. These data suggest severe gonadal toxicity in both men and women treated with the COPP/ABVD regimen. In female patients, drug-induced ovarian failure has a significant impact on bone mineralization.

Adolescent

Rearrangements of T-cell receptor delta, gamma and beta genes in acute myeloid leukemia coexpressing T-lymphoid features.

In order to investigate the role of T-cell receptor (TcR)-delta and TcR-gamma gene rearrangements and/or deletions in acute myeloid leukemia (AML) coexpressing T-cell-associated antigens (i.e. CD2 and/or CD4 and/or CD7), we examined blasts from a selected group of 56 AML cases (25 children, 31 adults) coexpressing either of these antigens without cytoplasmic CD3 expression. Forty-four typical AML cases (7 children, 37 adults) without T-cell associated antigens were further studied as controls. Germline configuration of the TcR-delta gene was observed in 91 out of the total of 100 AML cases investigated. Eight of nine cases with rearranged or deleted TcR-delta genes coexpressed T-cell-associated antigens. Blast cells of 7/9 cases were classified as FAB M1, two as FAB M2. In six of these cases TcR-gamma gene rearrangements were also detected. TcR-delta alterations were predominantly found in children whose blasts coexpressed T-lymphoid associated antigens (6/25, 24%), but were rarely detected in adult AML with or without coexpression of T-cell antigens (2/31 and 0/37, respectively).

Acute Disease

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