Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The molecular basis of the differential sensitivity of normal hematopoietic stem cells and of leukemia, lymphoma, and neuroblastoma cells to merocyanine 540 (MC540)-mediated photodynamic therapy (PDT) is not yet completely understood. While the capacity to bind dye molecules appears to be the major determinant of a cell's susceptibility of MC540-mediated PDT, we here present evidence that under certain experimental conditions a cell's capacity to repair MC540-mediated photodynamic damage is also an important factor. Two parameters, temperature and intracellular glutathione (GSH) content, were varied to investigate the role of cellular defense mechanisms in the dye-sensitized photoinactivation of normal murine granulocyte/macrophage progenitors (CFU-GM) and K562, L1210, and melphalan-resistant L1210/L-PAM1 leukemia cells. When exposed to MC540 and light at room temperature, the three leukemia cell lines bound similar amounts of dye and accumulated similar amounts of lipid hydroperoxide (LOOH) but differed markedly in their sensitivity to MC540-mediated PDT. Performing MC540-mediated PDT at 4 degrees C instead of at room temperature reduced dye binding and LOOH generation and enhanced cytotoxicity in some but not all cell lines. A brief (< or = 120 minutes) incubation at 37 degrees C immediately following MC540-mediated PDT accelerated the decay of LOOH in all leukemic cell lines and reduced cell kill by about 2 log in both CFU-GM and leukemia cells. The effect of post-PDT incubation at 37 degrees C on LOOH decay was most pronounced in K562 and least pronounced in L1210/L-PAM1 cells, whereas its effect on cell survival was less pronounced in L1210 cells than in the remaining cell types. L1210/L-PAM1 cells whose GSH content had been reduced from 8.2 to 1.6 micrograms/mg protein by incubation with buthionine sulfoximine recovered from potentially lethal photodynamic damage as rapidly as untreated L1210/L-PAM1 cells and more rapidly than wild-type L1210 cells with a GSH content of 4.5 micrograms/mg protein. Thus, with regard to capacity of L1210/L-PAM1 cells to recover from photodynamic damage, the cells' enhanced capacity to synthesize GSH appeared more decisive than intracellular GSH levels per se. Taken together, these data suggest that temperature-dependent cellular defense mechanisms are significant determinants of a cell's susceptibility to MC540-mediated PDT. The data emphasize the need for temperature control during and immediately after the photochemical purging of autologous bone marrow or peripheral blood stem cells.
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PMID:Role of cytoprotective mechanisms in the photochemical purging of autologous bone marrow grafts. 921 39

To evaluate the feasibility and efficacy of CD34+ cell immunoselection from routine peripheral blood stem cell (PBSC) harvests in very small children a prospective study was performed in 15 children with advanced neuroblastoma weighing 20 kg or less. Products of two consecutive leukaphereses carried out on a COBE Spectra separator after G-CSF alone mobilization were pooled for immunoselection on Ceprate column. The median number of CD34+ cells and total CFU-GM collected were respectively 5.9 x 10(6)/kg (range 2.3-23.4) and 126.9 x 10(4)/kg (range 52.9-559.9). After separation the median number of CD34+ cells in the adsorbed fraction was 2.6 x 10(6)/kg (range 1-9.8) with a median purity of 54% (range 21-82) and a median of 95.7-fold (range 35-250) enrichment. Thirteen patients underwent autografts with CD34+ PBSCs after a busulfan 600 mg/m2 + melphalan 180 mg/m2 preparative regimen. The median number of days to achieve an absolute granulocyte count of 0.5 x 10(9)/l and a platelet count of 20 x 10(9)/l were respectively, 12 (range 10-24) and 35 (range 25-43). The median number of platelet transfusions was nine (range 2-15). We conclude that safe and effective immunoselection and transplantation of CD34+ PBSC can be accomplished in children with low body mass.
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PMID:Feasibility of a PB CD34+ cell transplantation procedure using standard leukapheresis products in very small children. 925 86

Hematological and clinical data of 14 children with neuroblastoma treated according to the German neuroblastoma therapy study NB 90 were analyzed. Therapy included 4 or 8 intensive therapy elements N1 (Etoposide 125 mg/m2 day 1-4, Vindesine 3 mg/m2 day 1, Cisplatin 40 mg/m2 day 1-4) and N2 (Vincristine 1.5 mg/m2 day 1 + 8, Dacarbazine 200 mg/m2 day 1-5, Ifosfamide 1500 mg/ m2 day 1-5, Doxorubicin 30 mg/m2 day 6 + 7) in alternating order. The hematological recovery was studied after 86 therapy elements N1/N2. G-CSF had been given in 23 therapy courses, while no cytokine was administered in 63 therapy courses. Mobilization of CD34+ cells was studied in 13 therapy courses with G-CSF. Severe myelosuppression with an absolute neutrophil count < 500/microL was noted 2-4 weeks after each therapy element. The use of G-CSF did not prevent, but shortened neutropenia. There was no difference in the number of infections nor time delay of therapy between the courses with or without G-CSF. In 11 therapy courses G-CSF was started on the day following the last chemotherapy dose (N1: day 5; N2: day 9). In 12 therapy courses G-CSF was given delayed, starting day 12 after the initiation of therapy. Kinetics of granulocyte recovery was similar in the early or delayed application of G-CSF. Neutrophil recovery after the therapy element N1 was earlier and faster compared to that of therapy element N2. The more rapid rise of the neutrophils after the N1 element was accompanied by an effective mobilization of CD34+ cells. Taking into account the limitations of this retrospective study, the data may help to optimize the application of G-CSF in a very intensive therapy study like NB90.
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PMID:[Kinetics of myelopoietic regeneration and mobilization of CD34-positive cells within the scope of the NB90 Neuroblastoma Therapy Study]. 934 Apr 28

We have examined vaccination effects of cytokine-producing murine neuroblastoma cells (C1300). C1300 cells retrovirally transduced with interleukin-2 (IL-2) or granulocyte macrophage-colony stimulation factor (GM-CSF) gene were established. Their in vitro proliferation rates and the class I expression of major histocompatibility complex were not different from those of wild-type cells. Five-Gy irradiation of the respective cytokine producers slightly reduced the in vitro cell growth but treatment with 15 Gy significantly impaired the proliferation. In contrast, the secretion of both cytokines from the respective transduced cells was retained compared with the cell growth. We immunized syngeneic mice with irradiated wild-type cells as a control or cytokine-producing cells and challenged the mice with unirradiated wild-type cells. The control mice developed tumors of the challenged wild-type cells, on the contrary, the mice which had received irradiated IL-2 or GM-CSF producers did not. Thus, IL-2- or GM-CSF-expressing syngeneic tumor cells can be potentially used as a tumor vaccine by inducing protective immunity against low immunogenic neuroblastomas in the inoculated hosts.
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PMID:Antitumor vaccine effect of irradiated murine neuroblastoma cells producing interleukin-2 or granulocyte macrophage-colony stimulating factor. 962 5

Hemopoiesis is disturbed in bone marrow-involving cancers like leukemia and neuroblastoma. Shedding of gangliosides by tumor cells may contribute to this tumor-induced bone marrow suppression. We studied in vitro the inhibitory effects of murine neuroblastoma cells (Neuro-2a and C1300) and their gangliosides on hemopoiesis using normal murine hemopoietic progenitor colony-forming assays. Transwell cultured neuroblastoma cells showed a dose-dependent inhibition on hemopoiesis, indicating that a soluble factor was responsible for this effect. Furthermore, the supernatant of Neuro-2a cultured cells inhibited hemopoietic proliferation and differentiation. To determine whether the inhibitory effect was indeed due to shed gangliosides and not, for instance, caused by cytokines, the effect of DL-threo-1 -phenyl-2-decanoylamino-3-morpholino-1-propanol (DL-PDMP) on Neuro-2a cells was studied. DL-PDMP is a potent inhibitor of glucosylceramide synthase, resulting in inhibition of the synthesis and shedding of gangliosides. The initially observed inhibitory effect of supernatant of Neuro-2a cells was abrogated by culturing these cells for 3 days in the presence of 10 microM DL-PDMP. Moreover, gangliosides isolated from Neuro-2a cell membranes inhibited hemopoietic growth. To determine whether the described phenomena in vitro are a reflection of bone marrow suppression occurring in vivo, gangliosides isolated from plasma of neuroblastoma patients were tested for their effects on human hemopoietic progenitor colony-forming assays. These human neuroblastoma-derived gangliosides inhibited normal erythropoiesis (colony-forming unit-erythroid/burst-forming unit-erythroid) and myelopoiesis (colony-forming unit-granulocyte/macrophage) to a higher extent compared with gangliosides isolated from control plasma. Altogether these results suggest that gangliosides shed by neuroblastoma cells inhibit hemopoiesis and may contribute to the observed bone marrow depression in neuroblastoma patients.
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PMID:Inhibition of hemopoiesis in vitro by neuroblastoma-derived gangliosides. 980 88

We have evaluated the anti-tumor effect of anti-GD2 mouse monoclonal antibody (mAb) 220-51 against human neuroblastoma cell line TGW in vitro and in vivo. The mAb 220-51 was able to mediate complement-dependent cytotoxicity (CDC) and antibody-dependent cellular cytotoxicity (ADCC) using human effector cells. In the presence of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte ADCC was significantly augmented in vitro. When mAb 220-51 was administered to tumor-bearing nude mice, tumor growth was significantly inhibited as compared with untreated controls. Administration of recombinant murine GM-CSF in combination with mAb 220-51 significantly enhanced the anti-tumor effect of mAb in vivo. Recombinant human granulocyte colony-stimulating factor (G-CSF) combined with mAb 220-51 was also able to enhance it, although granulocyte ADCC was not affected by the presence of recombinant human G-CSF in vitro. Moreover, GM-CSF and G-CSF work additively to enhance the anti-tumor effect of mAb 220-51 in vivo. The GM-CSF and G-CSF may have a clinical potency in immunotherapy with anti-GD2 mAb for the treatment of neuroblastoma.
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PMID:Enhancement of in vitro and in vivo anti-tumor activity of anti-GD2 monoclonal antibody 220-51 against human neuroblastoma by granulocyte-macrophage colony-stimulating factor and granulocyte colony-stimulating factor. 985 37

Retroviral constructs were designed to express the novel cytokine interleukin 18 (IL-18), also known as interferon-gamma-inducing factor, in a murine neuroblastoma cell line [neuro-2a (N-2a)] to examine the effects of IL-18 expression on tumorigenicity. N-2a cells expressing proIL-18 (N-2a/IL-18p) were as tumorigenic as parental N-2a cells, whereas N-2a cells engineered to secrete mature IL-18 (N-2a/IL-18m) were nontumorigenic. Inoculation of mice with N-2a/IL-18m generated immediate immunity to parental N-2a. N-2a/IL-18m formed tumors in mice depleted of CD4+ and CD8+ T cells, suggesting that the antitumor immune response was T cell mediated. The resulting T-helper (Th) immune response was also characterized in vitro and had a large Th1 component based on in vitro production of the cytokines IFN-gamma and granulocyte macrophage colony-stimulating factor in response to tumor cells and IL-18.
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PMID:Neuroblastoma cells expressing mature IL-18, but not proIL-18, induce a strong and immediate antitumor immune response. 1040 34

The disease-free survival of children with malignant disorders has increased impressively over the last three decades due to better understanding of tumour biology and the resultant improvement in diagnosis and therapy. Children with advanced and relapsed solid tumours, such as brain tumour, alveolar rhabdomyosarcoma, Ewing's sarcoma, or neuroblastoma, have not benefited from this progress. The concept of myeloablative high-dose chemotherapy (HDT) is based on the observation that certain cytostatic drugs have a steep linear dose-response curve, and thus escalating the dose may increase the tumour cell kill. The interest in HDT intensified when autologous stem cells mobilised from the peripheral blood became available, in view of the possibility of increasing the cell dose, which correlates directly with the time period of haematopoietic recovery and thus reduces therapy-associated toxicity. The aim of the study was to evaluate the feasibility of single or double HDT by autologous peripheral blood stem cell transplantation (PBSCT) after each cycle in children, and to obtain pilot data for future prospective clinical trials. 11 children aged between 2.8 and 17.2 years with brain tumours, soft tissue sarcomas, germ-cell tumours and neuroblastomas were analysed over a 2-year-period. 7 of the 11 children are in complete remission 2+ and 24+ months after HDT, 3 died of progressive disease and one child died of therapy-associated complications. The median hospital stay was 29.5 (22-104) days. An absolute neutrophil granulocyte count of 0.5 x 10(9)/l was achieved after a median stay of 11 days and a platelet count of > 20 x 10(9)/l independent of platelet transfusions was achieved after 11 days. Painful stomatitis leading to total parenteral nutrition (9 children) and intravenous morphine therapy (6 children) was the most serious toxicity. Single or double HDT with autologous PBSCT after each cycle is feasible in children and offers basic data for conducting phase III paediatric clinical studies.
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PMID:[Single and double high-dose chemotherapy with autologous stem cell transplantation in children with advanced solid tumors: first experiences]. 1078 56

AC133, a newly discovered antigen on human progenitor cells, demonstrating 5-transmembranous domains is expressed by 30-60% out of all CD34+ cells. Our aim therefore was to investigate the extent of human stem-/progenitor cells expressing AC133 antigen in umbilical cord blood, peripheral blood without or following an application of granulocyte-colony stimulating factor (rhG-CSF). The main task was the investigation of bone marrow aspirates derived from children suffering from newly diagnosed acute leukemias, as well as from patients with a relapse or during a complete remission. The determination of antigen expression was done by application of flow cytometry (FACScan analysis) and the usage of newly developed monoclonal antibodies (AC133/1 and AC133/2; Miltenyi Biotec GmbH) in combination with monoclonal antibody directed against CD34-antigens (HPCA-2; BD). Our studies till now show average percentages in umbilical cord blood derived from 43 newborns about 0.294 +/- 0.165% AC133+ vs. 0.327 +/- 0.156% CD34+ hematopoietic stem-/progenitor cells (HSPC). In peripheral blood from 11 healthy donors we verified up to 0.15% CD34+ as well as AC133+ HSPC's. The concentration of progenitor cells was found to be obviously higher in peripheral blood from children with various diseases (neuroblastoma, rhabdomyosarcoma, ALL/AML) and undergoing application with rhG-CSF in order to be prepared for PBSC-transplantation. In those cases we found up to 3.51% AC133+ cells as well as slightly higher values (3.94%) for CD34 antigens. Additionally we quantified 128 bone marrow (BM) samples for AC133+ and CD34+ cells. In 10 BM samples, derived from patients without any neoplasia, the CD34+ cells were about 0.03% and 1.49%, whereas AC133 values were up to 0.64%. Bone marrow aspirates from 53 children with acute leukemias at time of diagnosis (ALL: n = 41/AML: n = 12) have been immunophenotyped and leukemic blast cells have been proved for AC133- and CD34 antigen expression. 32/41 (78%) of lymphoblastic leukemic cells showed to be positive for CD34 antigen and 24/41 (58%) demonstrated AC133 antigens. Interestingly there were 2 ALL-patients with pathological blast cells positive for AC133 but lacking of any CD34 antigens. 42% (5/12) of investigated AML patients showed CD34+ phenotype, on the other hand there were only 25% (3/12) with AC133+ phenotype. Similar values were found in relapsed patients (n = 18). In BM samples from patients during complete remission (n = 47) we could detect percentages up to 5.55% for CD34 and up to 1.25% for AC133 positive stem-/progenitor cells. Such quite high data may be explained by occasionally application of rhG-CSF therapy. Our results till now lead to the conclusion, that it seems to be useful, to recruit quantification of CD34+ HPSC by additionally detecting AC133 antigens. This new stem cell marker (AC133) may be of great value in case of autologous peripheral blood stem cell transplantation (PBSCT) because it could be an alternative to the usual CD34+ MACS selection system.
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PMID:[Expression of AC133 vs. CD34 in acute childhood leukemias]. 1091 77

Dendritic cells (DCs) have been shown to be a promising adjuvant for inducing immunity to cancer. We evaluated tumor lysate-pulsed DC in a Phase I trial of pediatric patients with solid tumors. Children with relapsed solid malignancies who had failed standard therapies were eligible. The vaccine used immature DC (CD14-, CD80+, CD86+, CD83-, and HLA-DR+) generated from peripheral blood monocytes in the presence of granulocyte/monocyte colony-stimulating factor and interleukin-4. These DC were then pulsed separately with tumor cell lysates and the immunogenic protein keyhole limpet hemocyanin (KLH) for 24 h and then combined. A total of 1 x 10(6) to 1 x 10(7) DC are administered intradermally every 2 weeks for a total of three vaccinations. Fifteen patients (ages 3-17 years) were enrolled with 10 patients completing all vaccinations. Leukapheresis yields averaged 2.8 x 10(8) peripheral blood mononuclear cells (PBMC)/kg, and DC yields averaged 10.9% of starting PBMC. Patients with neuroblastoma, sarcoma, and renal malignancies were treated without obvious toxicity. Delayed-type hypersensitivity (DTH) response was detected in 7 of 10 patients for KLH and 3 of 6 patients for tumor lysates. Priming of T cells to KLH was seen in 6 of 10 patients and to tumor in 3 of 7 patients as demonstrated by specific IFN-gamma-secreting T cells in unstimulated PBMCs. Significant regression of multiple metastatic sites was seen in 1 patient. Five patients showed stable disease, including 3 who had minimal disease at time of vaccine therapy and remain free of tumor with 16-30 months follow-up. Our results demonstrate that it is feasible to generate large numbers of functional DC from pediatric patients even in those highly pretreated and with a large tumor burden. The DC can be administered in an outpatient setting without any observable toxicity. Most importantly, we have demonstrated the ability of the tumor lysate/KLH-pulsed DC to generate specific T-cell responses and to elicit regression of metastatic disease.
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PMID:Vaccination of pediatric solid tumor patients with tumor lysate-pulsed dendritic cells can expand specific T cells and mediate tumor regression. 1173 36


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