PubMed Health⌕ Search

Biomedical subjects

R Handgretinger

Publications and source records attributed to R Handgretinger.

At least 91 records · Page 5Linked to original sources
PubMed1996

Immunohistochemical and cytogenetic findings in malignant rhabdoid tumor.

BACKGROUND: The histogenesis of malignant rhabdoid tumor (RT) remains a matter of controversy. From published reports it appears that some extrarenal RT (ERRT) exhibit neural or neuroectodermal features. Systematic investigation of renal RT (RRT) for neural differentiation has not yet been published. In this study, two RRT and two ERRT were investigated by light and electron microscopy, immunocytochemistry, and cytogenetic analysis. RESULTS: All four cases exhibited similar morphology and a largely consistent immunohistochemical staining profile. Both tumor types showed immunoreactivity for various cytokeratins, epithelial membrane antigen (EMA), vimentin, neurofilaments, S100 protein, neuron specific enolase, Leu7, CD34, p53, MB2, MIC2, VS38c, laminin and fibronectin. Reactivity was usually confined to a small proportion of the tumor cells, especially in the case of antibodies against neurofilaments, NSE, S100 proteins Leu7, CD34 and p53. Only a few of the antibodies (anti-vimentin, MB2, MIC2, anti-EMA, and VS38c) stained the majority of the tumor cells. Chromosome analysis revealed a discrete aberration in 11p (most probably a paracentric inversion in 11p15) in the one RRT investigated. One ERRT had a normal karyotype, but the other one exhibited various structural abnormalities on chromosomes 18 and 22. CONCLUSIONS: The immunohistochemical investigations revealed many similarities between RRT and ERRT, and all four tumors investigated exhibited neuroectodermal differentiation. As far as histogenetic classification is concerned, our findings point in the direction of the group of tumors that includes Ewing's sarcoma and primitive neuroectodermal tumors.

Cytogenetics↗
PubMed1995

The receptor tyrosine kinase p185HER2 is expressed on a subset of B-lymphoid blasts from patients with acute lymphoblastic leukemia and chronic myelogenous leukemia.

The class I receptor tyrosine kinase (RTK) HER2 is an oncoprotein that is frequently involved in the pathogenesis of tumors of epithelial origin. Here we report mRNA expression in peripheral blood and bone marrow cells from healthy donors in hematopoietic cell lines and leukemic blasts from patients with acute lymphoblastic leukemia (ALL), acute myeloblastic leukemia (AML), chronic lymphoblastic leukemia (CLL), and chronic myeloid leukemia (CML). However, cell surface expression of HER2 protein (p185HER2) was found exclusively on a subset of leukemic cells of the B-lymphoblastic lineage. p185HER2 expression was found on blasts in 2 of 15 samples from infants, 9 of 19 samples from adult patients with C-ALL (CD19+CD10+), and 1 of 2 samples from patients with pro-B ALL (CD19+CD10-), whereas none of the leukemic cells from patients with AML (0/30), T-ALL (0/7), CLL (0/5) (CD19+CD5+), or CML in chronic and accelerated phase (0/5) or in blast crisis with myeloid differentiation (0/14) were positive for p185HER2. However, cells from 3 of 4 patients with CML in B-lymphoid blast crisis (CD19+CD10+) expressed high levels of p185HER2, which was also found on the surface of the CML-derived B-cell lines BV-173 and Nalm-1. Our study shows p185HER2 expression on malignant cells of hematopoietic origin for the first time. Aberrant expression of this oncogenic receptor tyrosine kinase in hematopoietic cell types may be an oncogenic event contributing to the development of a subset of B-lymphoblastic leukemias.

3T3 Cells↗
PubMed1995

Presence of iron catalytic for free radical reactions in patients undergoing chemotherapy: implications for therapeutic management.

We investigated the kinetics of generation of iron 'catalytic' for free radical reactions in children with diagnosed acute lymphoblastic leukaemia (ALL) who received high-dose methotrexate infusions. In 76% of the chemotherapy courses studied, 'catalytic' iron appeared in plasma in the concentration range from 0.1 to 3 mumol/l. Positive correlations between maximum levels of 'catalytic' iron and plasma hepatic enzymes could be established in the majority of cases and in one subset of patients (low and medium risk ALL) mean 'catalytic' iron levels correlated well to clinically observable toxicities. The damaging potential of 'catalytic' iron was also demonstrated experimentally: oxidative damage to proteins was significantly (P < 0.05) higher in plasma samples showing the presence of 'catalytic' iron and in addition a strong correlation (r = 0.95, P < 0.02) was seen between plasma concentration of 'catalytic' iron and the ability of the plasma to stimulate lipid peroxidation. Our data show that chemotherapy releases 'catalytic' iron which may relate to toxic side effects. Hence binding this 'catalytic' iron by judicious co-administration of iron chelating agents could be beneficial in minimizing the iatrogenic adverse effects of chemotherapy of acute leukaemia.

Adolescent↗
PubMed1995

Non-syntenic amplification of MDM2 and MYCN in human neuroblastoma.

Amplification of the MYCN gene is a well documented genetic alteration of aggressively growing human neuroblastomas. Through cytogenetic studies we have identified neuroblastoma cell lines which, in addition to amplified MYCN, carry amplified DNA not harbouring MYCN. In situ hybridization of biotinylated total genomic DNA to metaphase chromosomes of normal human lymphocytes by reverse genomic hybridization revealed the amplified DNA to be derived from chromosome 12 band q13-14. Subsequent filter analyses showed a 20- to 40-fold amplification of the MDM2 gene, located at 12q13-14, both in three cell lines and in an original tumor, in addition to amplified MYCN. As the apparent consequence of amplification abundant MDM2 protein was present, a part of which was complexed with p53.

Chromosomes, Human, Pair 12↗
PubMed1995

Superantigen-staphylococcal-enterotoxin-A-dependent and antibody-targeted lysis of GD2-positive neuroblastoma cells.

Superantigens such as the staphylococcal enterotoxin A (SEA) are among the most potent T cell activators known. They bind to major histocompatibility complex (MHC) class II molecules and interact with T cells depending on their T cell receptor (TCR) V beta expression. Superantigens also induce a variety of cytokines and trigger a direct cytotoxic effect against MHC-class-II-positive target cells. In order to extend superantigen-dependent cell-mediated cytotoxicity (SDCC) to MHC-class-II-negative neuroblastoma cells, SEA was linked to the anti-ganglioside GD2 human/mouse chimeric monoclonal antibody (mAb) ch14.18. Ganglioside GD2 is expressed on most tumours of neuroectodermal origin but is expressed to a lesser extent on normal tissues. The linkage of ch14.18 to SEA was achieved either with a protein-A-SEA fusion protein or by chemical coupling. Both constructs induced T-cell-mediated cytotoxicity towards GD2-positive neuroblastoma cells in an effector-to-target(E:T)-ratio- and dose-dependent manner in vitro. To reduce the MHC class II affinity of SEA, a point mutation was introduced in the SEA gene (SEAm9) that resulted in 1000-fold less T cell killing of MHC-class-II-expressing cells as compared to native SEA. However, a protein-A-SEAm9 fusion protein mediated cytotoxicity similar to that of protein-A-SEA on ch14.18-coated, MHC-class-II-negative neuroblastoma cells. Taken together, these findings suggest that superantigen-dependent and monoclonal-antibody-targeted lysis may be a potent novel approach for neuroblastoma therapy.

Antibodies, Monoclonal↗
PubMed1995

A phase I study of human/mouse chimeric antiganglioside GD2 antibody ch14.18 in patients with neuroblastoma.

9 patients with stage IV neuroblastoma were treated with 19 courses of human/mouse chimeric monoclonal antiganglioside GD2 antibody ch14.18 at dose levels of 30, 40 and 50 mg/m2/day for 5 days per course. The maximum tolerated dose (MTD) per injection was 50 mg/m2/day. 7 patients received more than one course of treatment, and none revealed any human anti-mouse antibody (HAMA) response. Clinical side-effects of patients treated with ch14.18 were abdominal and joint pains, pruritus and urticaria. One patient presented with a transient pupillatonia, while 2 others showed a unilateral atrophy of the optical nerve that was probably attributable to prior therapies. A complete remission was seen in 2 patients, partial remission in 2 patients, a minor response in 1 patient and stable disease in 1 patient. 3 patients showed tumour progression. Thus, our results indicate that treatment with chimeric MAb ch14.18 can elicit some complete and partial tumour responses in neuroblastoma patients.

3-Iodobenzylguanidine↗
PubMed1995

Cytogenetic evolution of MYCN and MDM2 amplification in the neuroblastoma LS tumour and its cell line.

Amplification of the MYCN gene is frequently seen either in extrachromosomal double minutes (DMs) or in homogeneously staining regions (HSRs) of aggressively growing neuroblastomas. Total genomic DNA from cell line LS, from early passages of the same line and from original tumour material was biotinylated and hybridised to metaphase chromosomes of normal human lymphocytes. The reverse genomic hybridisation revealed the amplified DNA to be derived both from chromosome 2p23-24, which is the position of MYCN, and from chromosome 12 band q13-14. The MDM2 gene, located at 12q13-14, was found amplified both in early and late passages of LS, in addition to amplified MYCN. Amplification units of MYCN and MDM2 appear first to develop within DMs, which then integrate into different chromosomes to develop to HSRs.

Chromosomes, Human, Pair 12↗
PubMed1995

Clinical strategies for the treatment of neuroblastoma.

Neuroblastoma is the most common solid extracranial tumour in childhood. In spite of intensive efforts of clinicians and scientists the prognosis for advanced disease is still poor. This paper presents a short review of the state-of-the-art in conventional treatment including surgery, chemotherapy, and radiation. This is followed by a review of the treatment attempts with high dose chemotherapy followed by autologous bone marrow or stem cell transplantation. One of the main problems with this approach is the contaminating tumour cells. Finally the various immunotherapeutic strategies are summarised which are used to remove minimal residual disease. Later, our new approach, combining various treatment modalities, is described.

Child↗
PubMed1995

Autologous transplantation with peripheral blood stem cells in children and young adults after myeloablative treatment: nonrandomized comparison between GM-CSF and G-CSF for mobilization.

Recombinant human granulocyte-monocyte colony-stimulating factor (rhGM-CSF) was compared with recombinant granulocyte colony-stimulating factor (rhG-CSF) in 34 patients for mobilization of peripheral blood stem cells (PBSC) and for posttransplantation use. Peripheral blood stem cell mobilization was initiated by a single 1 h infusion of cyclophosphamide (4 g/m2) in all patients, followed by either a continuous infusion of rhGM-CSF (250 micrograms/m2/day) in 17 patients (group A) or a daily subcutaneous injection of rhG-CSF (10 micrograms/kg/day) in 17 patients (group B). PBSC were collected using a Fenwal CS 3000 continuous flow blood cell separator in one to three sessions. All patients suffered from various childhood malignancies. No difference in the number of collected cells among both groups was found. A mean of 2.7 x 10(8)/kg mononuclear cells (MNC) and of 7.9 x 10(4)/kg CFU-GM (colony-forming unit-granulocyte-macrophage) were collected in group A. In group B, 2.3 x 10(8)/kg MNC and 11.8 x 10(4)/kg CFU-GM were collected. In 33 patients, PBSC were reinfused after myeloablative therapy. Patients of group A (n = 17) were treated with rhGM-CSF (250 micrograms/m2/day) starting day +1, and patients in group B (n = 16) were treated with rhG-CSF (10 micrograms/kg/day) i.v. All patients showed a rapid and complete hematopoietic recovery without significant differences in both groups. Time to achieve 0.5 x 10(9)/L granulocytes was 10.9 days in group A and 11 days in group B.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

Expression of mdr1, mrp, topoisomerase II alpha/beta, and cyclin A in primary or relapsed states of acute lymphoblastic leukaemias.

In a series of 60 ALL samples drawn during different stages of the disease we used a cDNA-PCR approach to analyse the relative mRNA levels of the MDR-associated genes encoding mdr1/P-glycoprotein, mrp, and the topoisomerase II isozymes alpha and beta. Expression analysis of the cyclin A gene was included to examine cellular proliferation activity. The expression of gapdh served as an internal standard. Calculating the mean values we found: (i) a distinctly lower mdr1 gene expression in primary ALL and first relapses compared to bone marrow from healthy donors, (ii) no change in mdr1 and mrp, but a decreased topoisomerase II alpha gene expression in first relapses of ALL compared to the primary leukaemia, and (iii) increased mdr1 and mrp levels combined to decreased topoisomerase II alpha levels in recurrent relapses of ALL showing significant correlations (mdr1/mrp: rs = +0.6833, P < 0.05; mdr1/topoII alpha: rs = -0.6727, P < 0.05). The expression of the topoisomerase II alpha gene was correlated to that of cyclin A, indicating a link of its expression to cellular proliferation. Our findings suggest that a multifactorial MDR including mrp appears particularly in recurrent relapses of ALL, which often do not respond to chemotherapy. Nonetheless, some individual samples showed gene expression levels very different from the mean values calculated for a particular state of the leukaemia, indicating the need of an individual expression analysis of MDR-associated genes.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1995

Evidence for a lymphotropic nature of circulating plasmacytoid monocytes: findings from a case of CD56+ chronic myelomonocytic leukemia.

Because the cells previously designated plasmacytoid T cells share major immunophenotypic features with cells of the mononuclear-phagocyte system, they have been re-named and are now known as plasmacytoid monocytes (PM). We describe a unique case of chronic myelomonocytic leukemia with circulating PM. The patient, a 48-year-old man, presented initially with refractory anemia. Four years later his general condition deteriorated, accompanied by an increase in leukocytes to 200,000/microliters blood. The bone marrow histology was interpreted as compatible with a diagnosis of chronic myelomonocytic leukemia. Two months before he died, the patient developed generalized lymphadenopathy clinically simulating malignant lymphoma. Histologic examination of an axillary lymph node revealed diffuse infiltration by PM. The PM in the lymph node and some circulating cells closely resembling PM expressed L-selectin, a finding that could be interpreted as a morphologic correlate of their marked lymphotropism. The detection of large numbers of CD56/CD33 double-positive circulating blast cells by FACS analysis strongly supported the diagnosis of a leukemia of myelogenous origin. The patient died of tumor cachexia. Autopsy revealed widespread leukemic infiltrates (always containing clusters of PM) in bone marrow, spleen, liver, lymph nodes, and mucosa-associated lymphoid tissue of the oropharynx. The final diagnosis was one of chronic myelomonocytic leukemia with marked lymphotropism and partial differentiation towards PM. We consider that the rare instances of a hematologic tumor with differentiation towards PM should be classified amongst the myelogenous leukemias.

Antigens, CD↗
PubMed1995

Comparative analysis of the immunophenotypes of decidual and peripheral blood large granular lymphocytes and T cells during early human pregnancy.

PROBLEM: The functional role of the leukocytes in the decidual is not clear. They may regulate the maternal immune response to the fetal allograft. However, the factors controlling maternal and fetal communication have not yet been identified. METHOD: A comparative analysis of the phenotypes of decidual and peripheral blood large granular lymphocytes (LGLs) and T lymphocytes in early human pregnancy was performed on decidual tissue and blood samples obtained from ten patients at therapeutic abortion. RESULTS: Whereas most of the decidual LGLs were found to have a CD56bright++ phenotype, most of the peripheral blood NK cells (90%) showed the classical CD56dim+ phenotype, and only a small proportion were CD56bright+ cells. Another striking difference was found in the expression of very late antigen 1 (VLA-1, CD49a): Almost all the decidual CD56bright++ LGLs, but virtually none of the peripheral blood CD56+ NK cells expressed this antigen. Further differences were found in the expression of CD16, CD44, CD45RA, CD54, and CD57. There were also differences in phenotype between T cells derived from decidual tissue and those derived from peripheral blood. Approximately 31% of the CD3+ decidual T cells expressed VLA-1, but this antigen was virtually absent on peripheral blood T cells. A further difference was seen in the expression of HLA-DR. This activation antigen was found on 32 +/- 13% of the decidual T cells but only 8 +/- 5% of the peripheral blood T cells. Additionally, the proportion of cells expressing CD38 was higher among decidual than peripheral blood T cells. CONCLUSION: The findings suggest that both decidual LGLs and a subset of decidual T cells are activated and possibly play a role in the control of trophoblast growth and placental development.

CD56 Antigen↗
PubMed1995

[Functional significance of CD56 large granular lymphocytes in the decidua in early pregnancy in the human].

OBJECTIVE: The study was undertaken to characterize the large granular lymphocytes (LGL) found in large numbers in the decidua of early pregnancy, in order to investigate their functional significance in placentation. METHODS: The LGL were investigated by immunohistochemical, flow cytometric and molecular biological techniques. RESULTS AND CONCLUSIONS: The LGL resemble a small subpopulation of Natural Killer cells (NK-cells) in the peripheral blood, express activation antigens and produce cytokines that may have a regulatory/modulatory influence on trophoblast growth.

CD56 Antigen↗
PubMed1995

Remission of a lymphoproliferative disorder occurring after second BMT from an unrelated donor in a 5-year-old boy with severe aplastic anemia.

A 5-year-old boy with severe aplastic anemia failed to respond to cyclosporine (CYA), prednisolone and antilymphocyte globulin (ALG). No suitable sibling marrow donor was available, but an HLA-matched unrelated donor was identified. The patient was conditioned with cyclophosphamide (CY), 50 mg/kg/day for 4 days, total nodal irradiation (8 Gy), and ALG 30 mg/kg/day for 3 days. GVHD prophylaxis consisted of daily CYA, methotrexate (MTX) and ALG. The patient failed to achieve sustained engraftment. He was reconditioned with high-dose prednisolone and anti-T lymphocyte monoclonal antibody OKT3. The boy was reinfused with the same donor marrow on day 0 (+49/first BMT). No GVHD prophylaxis was given the second time. He received G-CSF on days 0 to +20 after the second transplant. Full engraftment was achieved on day +16 (+65). However, on day +31 (80) he developed a biopsy-proven B cell lymphoproliferative disorder (BLPD). After the OKT3 administration was stopped and treatment with ganciclovir and high-dose immunoglobulin was initiated, the BLPD resolved and the patient was discharged on day +50 (99). He is currently well with a functioning graft 266 (305) days posttransplant, with no sign of GVHD.

Anemia, Aplastic↗
PubMed1995

Allogenic peripheral blood stem cell (PBSC) transplantation in two patients with graft failure.

Allogenic peripheral blood stem cells (PBSC) were used for graft failure after BMT in two patients. These PBSC were mobilized by G-CSF in the same donors, harvested and given without reconditioning to the patients. In one patient, PBSC with a very high T cell number were given unprocessed, in the other patient, CD34+ cells were positively enriched due to a 2-antigen difference. None of the patients had hyperacute GVHD. Trilineage engraftment was seen after 13 days. Acute GVHD grade II to III developed on days +31 in patient 1 and +16 in patient 2, involving predominantly gut and liver, but sparing the skin. Thus, allogeneic PBSCT for graft failure did not cause hyperacute GVHD even with very high T cell numbers in patient 1, and graft failure with CD34 selected PBSC was successfully reversed even with a low number of T cells in patient 2.

Adolescent↗
PubMed1994

Rapid method for purification of CD56+ natural killer cells with preferential enrichment of the CD56bright+ subset.

A rapid method for the purification of CD56+ natural killer (NK) cells with the preferential enrichment of the CD56bright+ subset is described. The method is based on the adsorption of CD56+ cells indirectly stained with a biotinylated antibody on an avidin-coated column. The adsorbed CD56+ cells can then be squeezed out mechanically without damaging the viability or the function of the cells. Starting from peripheral mononuclear cells from adult donors, the recovery of the CD56+ cells was 11.9 +/- 9.0% (n = 8), the purity 93.0 +/- 4.9% (n = 10), and the enrichment factor 7.5 +/- 1.7 (n = 8). Further phenotypic classification of the CD56+ cells into CD56dim+ and CD56bright+ cells showed a preferential enrichment of the CD56bright+ phenotype with a recovery of 40.5 +/- 19.6% (n = 8), a purity of 30.3 +/- 13.2% (n = 8), and an enrichment factor of 29.8 +/- 7.2 (n = 8). In conclusion, the described method allows the rapid purification of CD56+ NK cells with the preferential enrichment of the CD56bright+ subset.

Adult↗