High dose chemotherapy and autologous hematopoietic cell transplantation for Wilms tumor: a study of the European Society for Blood and Marrow Transplantation.

Survival for subgroups of patients with Wilms tumor (WT), such as those who suffer from relapse, is disappointing. Some patients' treatment plans include high-dose chemotherapy (HDT) with autologous hematopoietic cell transplantation (aHCT), although proof for its benefit is lacking. To increase the level of evidence regarding children with WT receiving aHCT as consolidation of first or second remission (after first relapse), we extracted relevant data from the European Blood and Marrow Transplantation Registry concerning 69 patients. Different HDT regimens were administered, mostly either melphalan-containing (n = 34) or thiotepa-containing (n = 14). For the whole population, 5-year overall survival (OS) and event-free survival (EFS) probabilities were 0.67 (±0.06) and 0.63 (±0.06), respectively (median observation time 7.8 years); for children transplanted in first remission, OS and EFS were 0.69 (±0.09) and 0.72 (±0.08). In univariate analysis, male gender and relapse in multiple sites were associated with lower OS probabilities. The use of a given pretransplant regimen (i.e. melphalan alone versus regimens with multiple drugs) did not seem to influence EFS/OS probability after aHCT, but significantly influenced platelet engraftment (more delayed with thiotepa). We here provide further data to improve the basis for future evidence-based clinical decision-making when using HDT and aHCT in relapsed/refractory WT.

An open-label, multicentre, randomised phase 2 study of recombinant human granulocyte colony-stimulating factor (filgrastim) as an adjunct to combination chemotherapy in paediatric patients with metastatic neuroblastoma.

Administration of combination chemotherapy to children with metastatic neuroblastoma induces profound myelosuppression resulting in chemotherapy treatment delays and febrile neutropenic episodes. The objective of this randomised multicentre study was to assess the incidence, duration and severity of neutropenia when filgrastim is added to induction chemotherapy administered to patients with metastatic neuroblastoma. In this study, 59 patients with metastatic neuroblastoma were randomised to receive chemotherapy (control group, n = 28) or chemotherapy plus filgrastim (filgrastim group, n = 31). Chemotherapy consisted of four cycles of cyclophosphamide, vincristine and doxorubicin (CADO) alternating at 21-day intervals with cisplatin and etoposide (CDDP-VP16). Filgrastim was administered subcutaneously at a dose of 5 micrograms/kg/day from day 7 for up to 14 days. The incidence of neutropenia (absolute neutrophil count [ANC] < 0.5 x 10(9)/l) in the filgrastim group was not reduced after the first CADO course. However, significant reductions were observed after courses 2, 3 and 4. The duration of neutropenia and of intravenous antibiotic use were significantly reduced in the filgrastim group over the whole study period (9 days versus 26 days, P < 0.001; 12 days versus 20 days, P = 0.04, respectively). However, the duration of hospitalisation and the incidence of febrile neutropenia were not significantly reduced. Compliance to treatment was good and the ability to administer chemotherapy without treatment delays was significantly better in the filgrastim group (P < 0.05). Event-free survival was greater in the filgrastim than in the control group (2.4 years versus 1.3 years; P = 0.072). Filgrastim is a beneficial adjunct to combination induction chemotherapy used in the treatment of metastatic neuroblastoma.

In vivo induction of functional Fc gammaRI (CD64) on neutrophils and modulation of blood cytokine mRNA levels in cancer patients treated with G-CSF (rMetHuG-CSF).

Neutrophils from 13 children who received G-CSF for the collection of peripheral blood progenitors while they were in haematological steady state were studied at various times after G-CSF injection for Fc gammaR expression (Fc gammaRI or CD64, Fc gammaRII or CD32, and Fc gammaRIII or CD16) and for their ability to exert antibody-dependent cell cytotoxicity (ADCC) through Fc gammaRI. Changes in IFNgamma, IL8, IL10, MCP1 and TNF alpha mRNA levels in peripheral blood cells were also studied 4 h and 24 h after the first G-CSF injection. Fc gammaRI expression increased strongly after 24 h and then remained at the same level throughout treatment. In contrast, Fc gammaRIII expression sharply decreased at day 1 and diminished even further thereafter. No change in Fc gammaRII was observed. ADCC exerted by neutrophils through Fc gammaRI started to increase after 24 h with the peak level at day 5. Cytokine mRNA analyses indicated a reproducible and strong increase of IL8 mRNA (11/13 children) after 24 h, whereas the changes in the mRNA levels of the other cytokines tested were more heterogenous (TFNgamma: three; IL10: six; MCP1: five: TNF alpha: four, of the 13 children). Therefore this study opens the way to an optimized therapeutic schedule for the combined use of G-CSF and monoclonal antibodies in adjuvant immuno-intervention.

Induction of natural killer effectors from human thymus with recombinant IL-2.

The NKH1 Ag is expressed on all cells in human peripheral blood capable of mediating spontaneous non-MHC restricted cytolytic function (i.e., natural killing). The majority of NK cells do not express CD3 Ag and do not express TCR gene products. However, approximately 20 to 25% of NKH1+ cells coexpress CD3 and TCR proteins. Both NKH1+CD3+ and NKH1+CD3- effectors can proliferate in response to IL-2 which also results in enhancement of cytolytic function. In the present studies, we examined thymocytes after incubation with rIL-2 for the presence of NKH1+ cells and for the development of non-MHC restricted cytolytic function. NKH1+ cells and NK activity could not be detected in fresh thymus. After culture with rIL-2 only, NK activity appeared in 3 days, reached a maximum after 7 days, and was effective against a panel of NK-sensitive targets. NK activity was correlated with the expression of NKH1 on the surface of in vitro proliferating thymocytes and immunofluorescent cell sorting demonstrated that almost all cytolytic activity was mediated by NKH1+ cells. As expected given the thymic origin of these cells, the majority of NKH1+ cells in culture expressed CD3. However, all cultures contained NKH1+CD3- effector cells which represent 15 to 40% of the NKH1+ population. As in peripheral blood, both NKH1+CD3- and NKH1+CD3+ exhibited non-MHC-restricted cytotoxicity, but only CD3+ effectors could be inhibited by anti-T3 mAb. These findings demonstrate that rIL-2 alone can induce subpopulations of thymocytes to proliferate, to express the NKH1 marker and become NK active in vitro. Furthermore, they suggest that the thymus which plays a role in the differentiation of NKH1+CD3+ NK effectors may also play a role in the differentiation or maturation of NKH1+CD3- NK effectors.

Enhancement of natural killer function through activation of the T11 E rosette receptor.

Natural killer (NK) cells, which represent a small fraction of normal peripheral blood mononuclear cells, were purified by immunofluorescent cell sorting of NKH1+ cells. cytotoxicity of NKH1+ cells could be enhanced through activation by monoclonal antibodies (anti-T11(2) and anti-T11(3)) specific for epitopes of the sheep erythrocyte receptor or by recombinant interleukin-2 (rIL-2). After 18 h, incubation with both anti-T11(2/3) and rIL-2 resulted in similar levels of enhanced cytotoxicity against NK-resistant as well as NK-sensitive targets. Before and after induction, cytotoxicity was found predominantly within the NKH1+ population. These results suggest that several distinct mechanisms may be capable of enhancing NK activity and that the cells responsible for lymphokine-activated killing are likely to be the same population capable of spontaneous or natural killing before activation in vitro.