Search

The design of biomimetic coatings capable of improving the osseointegration of bone biomaterials is a current challenge in the field of bone repair. Toward this end, layer-by-layer (LbL) films composed of natural components are suitable candidates. Chondroitin sulfate A (CSA), a natural glycosaminoglycan (GAG), was used as the polyanionic component because it promotes osteoblast maturation in vivo. In their native state, GAG-containing LbL films are generally cytophobic because of their low stiffness. To stiffen our CSA-based LbL films, genipin (GnP) was used as a natural cross-linking agent, which is much less cytotoxic than conventional chemical cross-linkers. GnP-cross-linked films display an original combination of microscale topography and tunable mechanical properties. Structural characterization was partly based on a novel donor/acceptor Förster resonance energy transfer (FRET) couple, namely, FITC/GnP, which is a promising approach for further inspection of any GnP-cross-linked system. GnP-cross-linked films significantly promote adhesion, proliferation, and early and late differentiation of preosteoblasts.

Allogeneic hematopoietic SCT (HSCT) appears to be an efficient tool to cure high-risk AML in first CR but the choice between BU-based or TBI-based conditioning regimens still remains controversial. In order to analyze the impact of conditioning regimen on long-term survival, we conducted a retrospective analysis from French registry data including all consecutive patients under 18 years old (n=226) from 1980 to 2004 transplanted for AML in CR1 from sibling (n=142) or matched unrelated donors and given either TBI-1200 cGy and CY 120 mg/kg (TBI-Cy, n=84) or BU 16 mg/kg and CY 200 mg/kg (BuCy200, n=142). Patient subgroups were comparable for all criteria except for median age at diagnosis and HSCT and for donor type. Both 5-year OS and disease-free survival (DFS) were significantly better in BuCy200 group (P=0.02 and 0.005, respectively). In multivariate analysis, both HLA matching and BuCy200 appeared as good prognostic factors for treatment-related mortality and DFS. Grade 2-4 acute GvHD and chronic GvHD rates were statistically higher in TBI-Cy group than in Bu-Cy200 one with a RR at 2 (P=0.002). In total, Bu-Cy200 conditioning regimen gives better outcome compared with TBI-Cy irrespective of the stem cell source and the donor type.

Voltage-gated Na+ channels (VGSCs) are highly expressed in several types of carcinomas including breast, prostate and lung cancers as well as in mesothelioma and cervical cancers. Although the VGSCs activity is considered crucial for the potentiation of cancer cell migration and invasion, the mechanisms responsible for their functional expression and regulation in cancer cells remain unclear. In the present study, the role of the small GTPase RhoA in the regulation of expression and function of the Nav1.5 channel in the breast cancer cell lines MDA-MB 231 and MCF-7 was investigated. RhoA silencing significantly reduced both Nav1.5 channel expression and sodium current indicating that RhoA exerts a stimulatory effect on the synthesis of an active form of Nav1.5 channel in cancer cells. The inhibition of Nav1.5 expression dramatically reduced both cell invasion and proliferation. In addition, a decrease of RhoA protein levels induced by Nav1.5 silencing was observed. Altogether, these findings revealed: i) the key role of the small GTPase RhoA in upregulation of Nav1.5 channel expression and tumor aggressiveness, and ii) the existence of a positive feedback of Nav1.5 channels on RhoA protein levels.

Haematopoietic stem cells (HSCs) and haematopoietic progenitor cells (HPCs) grow in a specified niche in close association with the microenvironment, the so-called 'haematopoietic niche'. Scaffolds have been introduced to overcome the liquid culture limitations, mimicking the presence of the extracellular matrix (ECM). In the present study the hyaluronic acid scaffold, already developed in the laboratory, has been used for the first time to maintain long-term cultures of CD34⁺ haematopoietic cells obtained from human cord blood. One parameter investigated was the impact on ex vivo survival of CD34⁺ cord blood cells (CBCs) on the hyaluronic acid surface, immobilized with peptides containing the RGD motif. This peptide was conjugated by coating the hyaluronan hydrogel and cultured in serum-free liquid phase complemented with stem cell factor (SCF), a commonly indispensable cytokine for haematopoiesis. Our work demonstrated that these hyaluronan hydrogels were superior to traditional liquid cultures by maintaining and expanding the HPCs without the need for additional cytokines, and a colonization of 280-fold increment in the hydrogel compared with liquid culture after 28 days of ex vivo expansion., (Copyright © 2012 John Wiley & Sons, Ltd.)

Neuroblastoma malignant cell growth is dependent on their undifferentiated status. Arsenic trioxide (As2O3) induces neuroblastoma cell differentiation in vitro, but its mechanisms still remains unknown. We used three human neuroblastoma cell lines (SH-SY5Y, IGR-N-91, LAN-1) that differ from their MYCN and p53 status to explore the intracellular events activated by As2O3 and involved in neurite outgrowth, a morphological marker of differentiation. As2O3 (2μM) induced neurite outgrowth in all cell lines, which was dependent on ERK activation but independent on MYCN status. This process was induced either by a sustained (3 days) or a transient (2h) incubation with As2O3, indicating that very early events trigger the induction of differentiation. In parallel, As2O3 induced a rapid assembly of promyelocytic leukemia nuclear bodies (PML-NB) in an ERK-dependent manner. In conclusion, mechanisms leading to neuroblastoma cell differentiation in response to As2O3 appear to involve the ERK pathway activation and PML-NB formation, which are observed in response to other differentiating molecules such as retinoic acid derivates. This open new perspectives based on the use of treatment combinations to potentiate the differentiating effects of each drug alone and reduce their adverse side effects., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

We report French prospective experience with reduced-intensity conditioning-allo-SCT in 46 patients (median age: 15.5 years, 4.8-20.2) presenting high-risk AL (n=11), Hodgkin's lymphoma (n=15) or solid tumors (n=20). Graft sources were BM (n=21), PBSC (n=20) and cord blood (CB; n=5) from related (n=20) or unrelated (n=26) donors. For CB grafts, only one patient out of five achieved sustained engraftment. For PBSC/BM grafts, engraftment rate was 95%, hematopoietic recovery times were not significantly different between BM, PBSC, sibling or unrelated grafts, day+100. Full donor chimerism was achieved in 94% of patients, and incidences of primary acute GVHD and chronic GVHD were 49% and 14%, respectively. Underlying disease was fatal in 39% of patients. TRM was 6.9%. Three-year OS was 49.15%. OS and EFS were not significantly different between patients transplanted with different grafts and with or without primary GVHD. Patients with solid tumor or measurable disease at transplant had poorer outcomes. Three-year EFS: 33.3% for ALL, 75.0% for AML, 51.8% for Hodgkin's lymphoma, 28.6% for neuroblastoma and 22.2% for sarcoma patients. This multicentre study concluded that Bu/fludarabine/anti-thymocyte globulin conditioning with PB or BM, related or unrelated grafts in patients with various malignancies at high-risk for transplantation toxicity results in high engraftment rates, low TRM and acceptable survival.

The toxicity of cancer therapies can affect all organs and tissues. Some treatments damage spermatogonial stem cells (SSCs), with a risk of infertility. Storage and reimplantation of frozen testicular tissue is a recent approach tofertilitypreservationfor young boys. However, thawed frozen prepubertal testicular tissue must undergo a maturation process to restore sperm production. This process, currently being studied in animal models, can be achieved by in vivo transplantation of SSCs into seminiferous tubules or by testicular grafting, possibly following in vitro maturation.

Unlabelled: The aim of this study was to show that steroid therapy taken before the diagnosis of acute lymphoblastic leukemia (ALL) can alter the management of the disease., Patients and Methods: We conducted a multicenter retrospective study on 11 children treated between 2005 and 2011, who received oral steroids ranging from 0.6 to 3.3mg/kg/day prednisolone equivalent for a duration of 2 to 15 days during the 2 months prior to diagnosis of ALL., Results: Four children had febrile pancytopenia. Among them, 2 had severe infections and a noncontributive bone marrow aspiration. One of them presented a severe tumoral lysis syndrome and was hospitalized twice in the intensive care unit. Two teenagers had central nervous system involvement at diagnosis of T-ALL, 1 having associated cutaneous locations, the second one showing pulmonary and central nervous system (CNS) leukostasis with renal failure and disseminated intravascular coagulation. One child died of septic shock during the induction phase of steroid-resistant T-ALL. Four children had no complications during the induction phase. Steroid resistance occurred in 5 cases and steroid sensitivity could not be evaluated in 3 cases. Three allogeneic bone marrow transplants were performed: the first one because of early CNS relapse, the 2 others because of initial treatment resistance., Conclusion: Steroids can induce a delay in the management of ALL and seem to favor initial complications, and possibly increase diffuse locations as well as steroid resistance. Their prescription needs to be carefully managed, especially for uncharacteristic infectious symptoms. Then a complete blood count should be done., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Background: Rho GTPases are involved in cellular functions relevant to cancer. The roles of RhoA and Rac1 have already been established. However, the role of Rac3 in cancer aggressiveness is less well understood., Methods: This work was conducted to analyze the implication of Rac3 in the aggressiveness of two breast cancer cell lines, MDA-MB-231 and MCF-7: both express Rac3, but MDA-MB-231 expresses more activated RhoA. The effect of Rac3 in cancer cells was also compared with its effect on the non-tumorigenic mammary epithelial cells MCF-10A. We analyzed the consequences of Rac3 depletion by anti-Rac3 siRNA., Results: Firstly, we analyzed the effects of Rac3 depletion on the breast cancer cells' aggressiveness. In the invasive MDA-MB-231 cells, Rac3 inhibition caused a marked reduction of both invasion (40%) and cell adhesion to collagen (84%), accompanied by an increase in TNF-induced apoptosis (72%). This indicates that Rac3 is involved in the cancer cells' aggressiveness. Secondly, we investigated the effects of Rac3 inhibition on the expression and activation of related signaling molecules, including NF-κB and ERK. Cytokine secretion profiles were also analyzed. In the non-invasive MCF-7 line; Rac3 did not influence any of the parameters of aggressiveness., Conclusions: This discrepancy between the effects of Rac3 knockdown in the two cell lines could be explained as follows: in the MDA-MB-231 line, the Rac3-dependent aggressiveness of the cancer cells is due to the Rac3/ERK-2/NF-κB signaling pathway, which is responsible for MMP-9, interleukin-6, -8 and GRO secretion, as well as the resistance to TNF-induced apoptosis, whereas in the MCF-7 line, this pathway is not functional because of the low expression of NF-κB subunits in these cells. Rac3 may be a potent target for inhibiting aggressive breast cancer.

The vasculature of bone marrow differs from that in other organs, and its characteristics should be considered when exploring the medullar angiogenesis associated with hematological malignancies. We show here that the human bone marrow sinusoidal cell line HBME-1 has a specific expression pattern of angiogenic factors and receptors, characterized by a unique VEGFR3(+), Tie2(-) signature, that resembles the in vivo pattern. Moreover, the HBME-1 cultured for up to 3 days in hypoxic conditions, similar to those found in the bone marrow, specifically downregulated expression of VEGFR1, VEGFR2 and ETAR. Thus, a model using bone marrow sinusoidal cells cultured under reduced oxygen tension may be more relevant than classical in vitro endothelial cultures for understanding the interactions between endothelial and malignant cells in the medullar microenvironment., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The report describes the case of a young male with a malignant teratoma which was followed by an acute megakaryoblastic leukaemia sharing similar chromosomal abnormalities. In leukemic cells, the authors have obtained cytogenetic evidence by fluorescent in situ hybridisation technique suggesting that this leukaemia arose directly from the germ cell tumour (GCT). The patient received allogenic bone marrow transplantation, which unfortunately, did not prevent the patient to relapse with an undifferentiated sarcoma containing rhabdomyosarcoma components, as well as reappearance of a residual teratoma with metastasis. The treatment strategy for malignant transformation of a GCT seems to be unpredictable and should be dictated by the malignant tissue counterpart. Except for acute leukaemia, unresectable or metastatic settings will generally require multi-modal therapy including chemotherapy, in addition to loco regional approaches. Additionally, long or even a life time follow-up is necessary in patients with poor prognostic characteristics.

Aim of the Study: To determine whether a risk factor adapted chemotherapy would improve the outcome of non-metastatic bone Ewing's sarcoma., Methods: Standard risk tumours (SR, good histological response to chemotherapy or small unresected tumours) received the previous EW88 chemotherapy. Ifosfamide/etoposide (IE) were introduced after 3 courses of cyclophosphamide/doxorubicine when tumour regression was <50% or during consolidation therapy for the intermediate risk tumours (IR, intermediate histological response 5-30% residual cells or large unresected tumours >100ml). High risk tumours (HR, histological poor response >30% residual cells or clinical poor response <50% for unresectable tumours), received IE prior high dose busulfan/melphalan with stem cell rescue., Results: From 1993 to 1999, 214 patients were enrolled. 5 y-EFS and OS were 60% (95% confidence interval (CI), 53-66) and 69% (95% CI, 63-75), respectively. 116 (54%), 46 (21%), 48 (22%) patients were considered as SR, IR and HR of relapse, respectively. No advantage to IE was observed in the IR group. As compared to previous study, tumour with poor histological response to induction chemotherapy seemed to benefit from the consolidation strategy including busulfan/melphalan: EFS were 45% (95% CI, 30-60) and 20% (95% CI, 7-43) for EW93 and EW88, respectively. Despite a risk-adapted strategy, histological response to chemotherapy remains the main prognostic factor in resected tumours, while initial tumour volume is the main prognostic factor for unresected tumours., Conclusion: These results showing a potential benefit of a consolidation strategy including busulfan/melphalan as compared to conventional chemotherapy needed confirmation by a randomised trial and were one of the bases of the ongoing EuroEwing99., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Transfusion programs are sometimes necessary to take care of severe sickle-cell patients. Treatment of cerebrovascular disease in sickle-cell disease is the most common indication. Periodic automated red blood cell exchange (erythrocytapheresis) is an alternative treatment. Sixteen patients less than 20 years old have been treated with chronic erythrocytapheresis since 2004 in the pediatric hematology and oncology department of the University Hospital of Rouen, 10 patients for cerebrovascular disease (1 was on secondary prevention and 9 were on primary prevention), 5 patients for pain crisis recurrence, and the last one for mild psychocognitive deficit disorder. This treatment was unsuccessful for 4 patients, 3 on primary prevention and 1 treated for pain crisis recurrence. These failures were caused by alloimmunization for 2 patients and venous access problems for 2 patients. For the other 12 patients, 5 of the 6 patients on primary prevention showed clear improvement (normalization of transcranial Doppler ultrasound or improvement on magnetic resonance angiography), the patient on secondary prevention had stability on cerebral MRI after 2 years of treatment, the 5 patients with pain crisis recurrence had good improvement, and psychocognitive abilities improved for the last patient. One hundred and ninety-nine erythroexchange sessions were performed for the 9 patients treated over a period of 10 to 30 months. Erythrocytapheresis sessions ran on average less than 1.5h. Three patients showed high ferritin levels at the beginning of erythroexchange, which normalized 2 to 10 months later. All patients reported better quality of life. Periodic erythroexchanges are an effective treatment for complicated sickle-cell anemia and iron overload. It requires human, material, and financial support, but not as much as simple transfusion or manual erythroexchange. Practical experience shows problems of venous access because of coagulation when sampling., (Copyright © 2012. Published by Elsevier SAS.)

Seeking to improve ovarian cancer therapy, we compared biological characteristics of the moderately-aggressive OVCAR-3 cell line with two highly aggressive ovarian cancer cell populations: the SK-OV-3 cell line, and HASCJ primary cells isolated from the ascitic fluid of a patient with FIGO stage IV ovarian cancer. Secretion of angiogenic factors was not discriminative, whereas cell invasion through Matrigel and vasculogenic mimicry were much greater in the more aggressive cells. Among 10 agents tested for their ability to decrease cancer cell aggressivity using these two models, inhibitors of Stat3, IGF-IR and Rho GTPase were found to be the most promising., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Viral respiratory infections are potentially life-threatening among children treated for cancer. We report a nosocomial outbreak of six cases of pandemic influenza A/H1N1/2009 on a paediatric haematology and oncology ward. Three patients developed pneumonia and two of them sustained haemodynamic collapse. The source was probably a relative of the first infected patient. The outbreak was probably spread by cross-infection between patients during communal activities. A few days' delay in identifying the outbreak promoted spread of the influenza. Infection control measures included the use of oral oseltamivir treatment for all hospitalised patients, isolation of the infected patients, strict personal protective controls and a restriction on visitors. No new cases occurred after implementation of these containment measures. At the time when the outbreak was identified, all the patients were already isolated for other reasons. We conclude that A/H1N1/2009 influenza may spread rapidly and cause severe infection in paediatric cancer patients but can be efficiently contained. Identification of isolated or clustered cases should lead to the rapid implementation of appropriate infection control measures., (Copyright © 2011 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.)

Background: Tetraspanins are transmembrane proteins known to contribute to angiogenesis. CD9 partner-1 (CD9P-1/EWI-F), a glycosylated type 1 transmembrane immunoglobulin, is a member of the tetraspanin web, but its role in angiogenesis remains to be elucidated., Methods: We measured the expression of CD9P-1 under angiogenic and angiostatic conditions, and the influence of its knockdown onto capillary structures formation by human endothelial cells (hECs). A truncated form of CDP-1, GS-168AT2, was produced and challenged vs hEC proliferation, migration and capillaries' formation. Its association with CD9P-1, CD9, CD81 and CD151 and the expressions of these later at hEC surface were analysed. Finally, its effects onto in vivo tumour-induced angiogenesis and tumour growth were investigated., Results: Vascular endothelial growth factor (VEGF)-induced capillary tube-like formation was inhibited by tumour necrosis factor α and was associated with a rise in CD9P-1 mRNA expression (P<0.05); accordingly, knockdown of CD9P-1 inhibited VEGF-dependent in vitro angiogenesis. GS-168AT2 dose-dependently inhibited in vitro angiogenesis, hEC migration and proliferation (P<0.05). Co-precipitation experiments suggest that GS-168AT2 corresponds to the sequence by which CD9P-1 physiologically associates with CD81. GS-168AT2 induced the depletion of CD151, CD9 and CD9P-1 from hEC surface, correlating with GS-168AT2 degradation. Finally, in vivo injections of GS-168AT2 inhibited tumour-associated angiogenesis by 53.4±9.5% (P=0.03), and reduced tumour growth of Calu 6 tumour xenografts by 73.9±16.4% (P=0.007) without bodyweight loss., Conclusion: The truncated form of CD9P-1, GS-168AT2, potently inhibits angiogenesis and cell migration by at least the downregulation of CD151 and CD9, which provides the first evidences for the central role of CD9P-1 in tumour-associated angiogenesis and tumour growth.

Background: Complications of bone marrow transplantation (BMT) are usually considered to be related to the secretion of inflammatory cytokines, which generate membrane microparticles rich in procoagulant phospholipids (PPL) from different cellular origins and release of endothelial proteins such as thrombomodulin (TM). The use of soluble TM quantified by ELISA (TM:Ag) as a marker of endothelial injury is complex in children since it is age-dependent., Materials and Methods: Using a functional assay which quantifies the activity of sTM activity (TMa), we performed a pilot study to analyze the ratio TMa/TM:Ag in a control group of 25 healthy children, 8 children with autologous and 16 children with allogeneic BMT. In this last group, 8 experienced BMT complications. In addition, we used a functional assay which quantifies PPL., Results: In healthy children the ratio TMa/TM:Ag was independent of age and stable in children with a favorable outcome but significantly (p<0.05) reduced by the use of antithymocyte globulin during the conditioning regimen, and regularly decreased in children with BMT complications. Surprisingly, low plasma PPL levels were associated with a poor outcome., Conclusion: The ratio TMa/TM:Ag could constitute a marker of endothelium injury, and its follow-up could be of interest for an early discrimination of children with high risk of complications during allogeneic BMT. The decrease of PPL could be also another marker of a poor evolution and deserves further investigations., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Acute lymphoblastic leukaemia (ALL) is characterized by malignant cell infiltration of bone marrow, requiring chemotactic response to SDF-1α. Using time-lapse video, we measured the velocity of ALL cells on fibronectin, and found that SDF-1α increased their migration activity for 2 h, but had no effect after 4h, following internalization of its receptor CXCR4. Transfection of ALL cells with dominant-negative Rac1 mutant significantly prolonged their chemotactic response to SDF-1α, and this effect was associated with an alteration of CXCR4 internalization. These data suggest a regulatory role for Rac1 in the chemotactic response of ALL cells to SDF-1α via receptor processing., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Gaucher disease is the most frequent lysosomal storage disease. It is a progressive chronic disease that can lead to substantial bone and joint damage and hematological cytopenias. This progressive disease severely worsens the patients' quality of life. Over the past 20 years, enzymatic treatment has considerably improved both symptoms and quality of life. Yet, bone and joint damage may be irreversible. This emphasizes the importance of rigorous follow-up so as to begin uninterrupted treatment before lesion onset. The transition from pediatric to adult care is a major concern for chronic patients. This step is often associated with follow-up problems and may lead to disease worsening. We present three cases of patients who were lost to follow-up during the transition phase. For all 3 patients, the disease notably worsened because follow-up was interrupted during this period., (Copyright © 2010 Elsevier Masson SAS. All rights reserved.)

In children, lymphoblastic lymphomas represent 30% of Non-Hodgkin lymphomas (NHL), and approximately 15% are precursor B-cell lymphomas (PBLL). Our study evaluated their main clinical characteristics, evolution, and prognosis in three trials. From 1989 to 2008, 53 children with PBLL (median age 7·75 years) were included in three protocols: Malignant Lymphoma Therapy (LMT) 96, European Organization for Research and Treatment of Cancer (EORTC) 58881, and EORTC 58951 using Berlin-Frankfürt-Münster-derived acute lymphoblastic leukaemia (ALL) therapy. There were 10 stage I disease, 9 stage II, 9 stage III and 25 stage IV. Clinical presentation was heterogeneous with a majority of bone lesions and cutaneous or subcutaneous manifestations. At diagnosis 23 patients had bone marrow involvement, and only three had central nervous system involvement. The median follow-up was 74 months. At last follow-up, 45 patients were in continuous complete remission, whereas eight had progressed or had relapsed (7 Stages IV and 1 Stage III) and died. Two patients had a secondary neoplasia, and are still alive. Disease stage was a major prognostic factor, with better overall survival (OS) and event-free survival (EFS) (P < 0·05) rates observed in patients with Stage I to III as compared to those with Stage IV. Treatment with protocols derived from ALL therapy are efficient with an 82% EFS and an 85% OS at 5 years., (© 2011 Blackwell Publishing Ltd.)

Background: Loss of CD9 expression has been correlated with a higher motility and metastatic potential of tumour cells originating from different organs. However, the mechanism underlying this loss is not yet understood., Methods: We produced a truncated form of partner 1 of CD9 (CD9P-1), GS-168AT2, and developed a new monoclonal antibody directed towards the latter. We measured the expression of CD9 and CD9P-1 in human lung tumours (hLTs), and monitored the level of CD9 in NCI-H460, in vitro and in vivo, in the presence and absence of GS-168AT2., Results: Loss of CD9 is inversely related to the expression of CD9P-1, which correlates with the metastatic status of hLT (n=55). In vitro, GS-168AT2 is rapidly internalised and degraded at both the membrane and cytoplasm of NCI-H460, and this correlates with the association of GS-168AT2 with both CD9 and CD81. Intraperitoneal injections of GS-168AT2 in NCI-H460-xenografted Nude mice led to drastic inhibition of tumour growth, as well as to the downregulation of CD9, but not of CD81, in the tumour core., Conclusion: These findings show for the first time that CD9P-1 expression positively correlates with the metastatic status of hLT, and that the upregulation of CD9P-1 expression could be one of the mechanisms underlying the loss of CD9 in solid tumours. Our study also reveals that, under certain conditions, loss of CD9 could be a tumour growth-limiting phenomenon rather than a tumour growth-promoting one.

Infantile fibrosarcoma is a rare malignant tumor that usually occurs during the 1st year of life. It accounts for approximately 5-10% of all sarcomas in infants younger than 1 year of age. It usually has indolent progression and metastatic spread is rare. We report the case of a patient who had infantile fibrosarcoma of the trunk. At birth, the baby presented a soft tissue mass of the scapulothoracic region. Histopathological examination after complete surgical resection at first suggested an angioma. Reanalysis of the histology after a metastatic relapse resulted in the diagnosis of infantile fibrosarcoma, which was confirmed by the presence of the specific translocation seen in infantile fibrosarcoma (ETV6/NTRK3). This patient's progression was uncommon because he developed 3 metastatic relapses. The treatment consisted of surgery, chemotherapy, and radiation therapy. The patient is alive with persistent complete remission. We discuss the diagnostic and therapeutic issues of infantile fibrosarcoma. There is a risk of erroneous diagnosis in newborn infants between benign angiomatous tumor and infantile fibrosarcoma. The fusion transcript ETV6-NTRK3 resulting from the specific chromosomal translocation t(12;15)(p13;q25) is now a useful diagnostic tool for infantile fibrosarcoma. Surgery with wide resection is the mainstay of treatment. However, infantile fibrosarcoma is a chemosensitive tumor. If initial surgery cannot be done without mutilation or is impossible, preoperative chemotherapy should be given. The role of radiation therapy is still debated., (Copyright © 2010 Elsevier Masson SAS. All rights reserved.)

The role of angiogenesis in acute leukaemia has been discussed since the cloning of the gene of vascular endothelial growth factor (VEGF) from the acute myelogenous leukemia cell line (HL60) and, thereafter, when the first studies reported increased bone marrow vascularity and elevation of angiogenic cytokines in acute lymphoblastic leukaemia (ALL). VEGF and basic fibroblast growth factor (bFGF) are the major proangiogenic cytokines that have been studied, and evaluation of their prognostic impact in childhood ALL has been reported in several studies, though with controversial results. The antiangiogenic response, contributing to the angiogenic balance, has scarcely been reported. The origin of the factors, their prognostic value, and their relevance as good markers of what really happens in the bone marrow are discussed in this paper. The place of antiangiogenic drugs in ALL has to be defined in the global treatment strategy.

Transient receptor potential canonical (TRPC) channels are key players in calcium homeostasis and various regulatory processes in cell biology. Little is currently known about the TRPC subfamily members in mesenchymal stem cells (MSC), where they could play a role in cell proliferation. We report on the presence of TRPC1, 2, 4 and 6 mRNAs in MSC. Western blot and immunofluorescence staining indicate a membrane and intracellular distribution of TRPC1. Furthermore, the decrease in the level of TRPC1 protein caused by RNA interference is accompanied by the downregulation of cell proliferation. These results indicate that MSC express TRPC1, 2, 4 and 6 mRNA and that TRPC1 may play a role in stem cell proliferation.

Vascular endothelial-specific cadherin (VE-cadherin) is an endothelial cell-specific adhesion molecule, localized at cell-cell contact sites. It is involved in physiological and pathological angiogenesis. In this study, we showed that in vitro a soluble N-terminal fragment of VE-cadherin (EC1-3) corresponding to cadherin 1-3 ectodomains inhibited vascular endothelial growth factor-stimulated endothelial cell proliferation and capillary tube structure formation in the matrigel model. In vivo, EC1-3 was tested in a murine colon cancer model. EC1-3-expressing colon cancer C51 cells were subcutaneously grafted into nude mice, and tumor growth and angiogenesis were evaluated. At day 33, the mean volume of the tumors developed was reduced (510±104 versus 990±120 mm(3) for control). Similarly, injection of EC1-3 virus-producing cells into established C51 tumors resulted in an inhibition by 33% of tumor growth. Immunohistological staining of vessels on tumor sections showed a significantly reduced intratumoral angiogenesis. Furthermore, EC1-3 did not induce vessel injury in the lung, liver, spleen, heart and brain in the mice. These results suggest that the soluble N-terminal fragment of VE-cadherin EC1-3 could exert an antitumoral effect by targeting tumor angiogenesis, which included blocking endothelial cell proliferation and capillary tube formation with no obvious toxicity on normal organs.

Background: Infiltration by macrophages (Mphi) indicates a poor prognosis in breast cancers, in particular by inducing angiogenesis. Our study aimed 1) to investigate the mechanism by which cooperation between Mphi and aggressive breast cancer cells (MDA-MB-231) induces angiogenesis; 2) to examine the effect of tetrathiomolybdate (TM) on this angiogenic activity., Methods: Mphi coincubated with MDA-MB-231 were used as a model to mimic the inflammatory microenvironment. Angiogenesis induced by the culture media was tested in the chick chorioallantoic membrane (CAM). Mphi phenotype was evaluated by 1) expression of the M1 marker CD80, and secretion of interleukin 10 (IL-10), an M2 marker; 2) capacity to secrete Tumour Necrosis Factor alpha (TNFalpha) when stimulated by lipopolysaccharide/interferon gamma (LPS/IFNgamma); 3) ability to induce MDA-MB-231 apoptosis. To explore the molecular mechanisms involved, cytokine profiles of conditioned media from MDA-MB-231, Mphi and the coculture were characterised by an antibody cytokine array. All experiments were carried out both in presence and in absence of TM., Results: Incubation of Mphi with MDA-MB-231 induced a pro-angiogenic effect in the CAM. It emerged that the angiogenic activity of the coculture is due to the capacity of Mphi to switch from M1 Mphi towards M2, probably due to an increase in Macrophage Colony Stimulating Factor. This M1-M2 switch was shown by a decreased expression of CD80 upon LPS/IFNgamma stimulation, an increased secretion of IL-10, a decreased secretion of TNFalpha in response to LPS/IFNgamma and an inability to potentiate apoptosis. At the molecular level, the angiogenic activity of the coculture medium can be explained by the secretion of CXC chemokines/ELR+ and CC chemokines. Although TM did not modify either the M2 phenotype in the coculture or the profile of the secreted chemokines, it did decrease the angiogenic activity of the coculture medium, suggesting that TM inhibited angiogenic activity by interfering with the endothelial cell signalling induced by these chemokines., Conclusions: Cooperation between Mphi and MDA-MB-231 transformed M1 Mphi to an angiogenic, M2 phenotype, attested by secretion of CXC chemokines/ELR+ and CC chemokines. TM inhibited this coculture-induced increase in angiogenic activity, without affecting either Mphi phenotype or cytokine secretion profiles.

The use of L-asparaginase (L-ASP) in paediatric patients with acute lymphoblastic leukaemia (ALL) is associated with thrombotic complications. We evaluated the activities of tissue factor (TFa), thrombomodulin (TMa) and procoagulant phospholipids (PPL) in 26 consecutive children with ALL (25 B-ALL and one T-ALL) treated by the French Acute Lymphoblastic Leukemia group (FRALLE)-2000 protocol. Samples were obtained at diagnosis, after glucocorticoid (GC) therapy, during the induction phase with L-ASP, vincristine (VCR) and adriamycin (ADR), during the re-induction and within the week after treatment. Plasma levels of TFa, TMa and PPL increased gradually and significantly during the different phases of the treatment, with higher levels observed during the induction period, and decreased after treatment discontinuation. In vitro studies showed that the different drugs used for ALL treatment could induce a weak expression of TF and procoagulant activity (PCA) on normal and leukaemia blood cells, while a marked effect was observed on endothelial cells. In conclusion, these data indicate that, in addition to the well-identified increased in coagulation factors and inhibitor deficiencies, the injury of the endothelium could lead to the release of TF and PPL and could contribute to the hypercoagulability of children treated for ALL.

Matrix metalloproteases (MMPs) are endopeptidases involved in tumor cell invasion. Childhood acute lymphoblastic leukemia (ALL) is characterized by its capacity to infiltrate different organs. We analyzed the expression of MMP-2, -9, -14 and TIMP-1 and -2 in a prospective study on 86 children with newly diagnosed ALL (73 B- and 13 T-lineage) and 9 children at relapse with B-ALL. Membrane-bound and intracytoplasmic MMPs and TIMPs were analyzed by flow cytometry, and secreted MMPs were quantified by ELISA. In patients at relapse, MMP-14 was present in a greater proportion of the B-ALL cell population than at diagnosis. In patients with peripheral infiltration, intracytoplasmic MMP-9 was significantly higher than in patients without infiltration. ROC curve and Kaplan-Meier curve analysis showed that a high secretion of MMP-9 (>2450 pg/ml/10(6) cells) was associated with a lower overall survival rate, suggesting that the secretion of MMP-9 is an independent prognostic factor in childhood B-ALL., (2009 Elsevier Ltd. All rights reserved.)

Aims: To examine the efficacy and safety of pegfilgrastim in patients with congenital neutropenia (CN)., Methods: Seventeen patients enrolled in the French Severe CN Register received pegfilgrastim., Results: Median age at pegfilgrastim introduction was 19.1 years (range 3.9-52.3 years). In 14 cases pegfilgrastim replaced GCSF (filgrastim or lenograstim), after a median of 6.9 years of GCSF therapy. The dose of pegfilgrastim was usually one full vial per injection (except in five children, who received 1/6 to 1/2 a vial), resulting in a dose of between 50 and 286 microg/kg. The pegfilgrastim schedule ranged from two injections every 7 days to one injection every 30 days, with treatment-free periods. The median interval between the first and last dose of pegfilgrastim was 0.8 years (0.01-4.1 years). The absolute neutrophil count tended to increase more strongly on pegfilgrastim than on GCSF, but the difference was not statistically significant. During pegfilgrastim therapy, a severe infection occurred in two patients and recurrent ENT infections in two other patients. Bone pain was reported by nine patients, anemia and thrombocytopenia occurred in one patient (WHO grade III), chronic urticaria occurred in one patient (WHO grade III), and a single pegfilgrastim injection was followed by respiratory distress and death 15 days later in a patient with GDSIb. At the last update, 10 patients had stopped receiving pegfilgrastim and seven patients were still receiving pegfilgrastim., Conclusion: Compared to conventional GCSF, pegfilgrastim is more difficult to use in congenital neutropenia, with more frequent adverse events and sometimes poor efficacy.

In the most common primary brain tumors, malignant glioma cells invade the extracellular matrix (ECM) and proliferate rapidly in the cerebral tissue, which is mainly composed of hyaluronan (HA) along with the elastin present in the basement membrane of blood vessels. To determine the role of ECM components in the invasive capacity of glioma cell lines, we developed a 3-D cell-culture system, based on a hydrogel in which HA can be coreticulated with kappa-elastin (HA-kappaE). Using this system, the invasiveness of cells from four glioma cell lines was dramatically increased by the presence of kappaE and a related, specific peptide (VGVAPG)(3). In addition, MMP-2 secretion increased and MMP-12 synthesis occurred. Extracellular injections of kappaE or (VGVAPG)(3) provoked a pronounced and dose-dependent increase in [Ca(2+)](i). kappaE significantly enhanced the expression of the genes encoding elastin-receptor and tropoelastin. We propose the existence of a positive feedback loop in which degradation of elastin generates fragments that stimulate synthesis of tropoelastin followed by further degradation as well as migration and proliferation of the very cells responsible for degradation. All steps in this ECM-based loop could be blocked by the addition of either of the EBP antagonists, lactose, and V-14 peptide, suggesting that the loop itself should be considered as a new therapeutic target.

In children with acute lymphoblastic leukemia (ALL), leukemic cells express several members of the VEGF family and the three VEGF receptors which, via an autocrine loop are responsible for secretion of MMP-2/-9. MMP activity and the presence of elements of the autocrine loop are correlated with clinical and prognostic parameters as follows: i) high basal MMP-9 activity with tumoral syndrome, ii) MMP-2 activity with treatment failure, iii) VEGFR-1/-3 co-expression with high hemoglobin level and iv) expression of the VEGF-A 121 isoform and favorable response to treatment. These data implicate autocrine VEGF-induced secretion of MMP-2/-9 in the physiopathology of childhood ALL.

Invasive hospital-acquired aspergillosis (IA) is responsible for lethal outbreaks. In 2002, an interdisciplinary team was created in the teaching hospital of Rouen in order to organize the surveillance of construction sites by the implementation of environmental measures of prevention. The aim of our study was to estimate the efficiency of these measures using an indirect indicator, reflecting the incidence of the cases of invasive nosocomial aspergillosis (AI): the consumption of antifungals. From the nominative prescriptions established, we studied the medical files about 210 patients to track down the number of IA cases in intensive care unit (ICUI) and in pediatric hematology-oncology units between 2002 and 2006. The incidence of the cases was put in parallel with the various periods of level 5-risk works during these five years. The relative risk of appearance of the disease was calculated. In pediatric haematology-oncology unit, 35 cases were diagnosed on 99 medical files which have been studied and in ICU 19 cases were classified on 93 studied files. The follow-up of the incidence in both units stake in parallel with the periods of level 5-risk works does not show increase of the number of cases. The calculated relative risk indicates the same result: the level 5-risk works are not a factor facilitating the appearance of invasive aspergillosis cases. This study shows the importance of the environmental measures of prevention during the periods of works within services for risk. The coordination of the actors within an interdisciplinary cell seems thus essential for the prevention of AIN.

Background: We explored the heterogeneity of philadelphia chromosome-positive acute lymphoblastic leukemia (Ph1-ALL) in a study of the effect of early features on prognosis in children. Here we report the long-term results of the FRALLE 93 study conducted in the era before the use of tyrosine kinase inhibitors., Methods: Between 1993 and 1999, 36 children with Ph1-ALL were enrolled into the FRALLE 93 protocol. After conventional four-drug induction, children were stratified by availability of an HLA-matched sibling., Results: Complete remission (CR) was observed in 26 children (72%), of which 13 underwent allogeneic bone marrow transplantation (BMT). Thirty-one children were good responders to prednisone, defined on day 8, and 21 were good responders to chemotherapy, defined by day-21 bone marrow (M1). Overall five-year disease-free survival (DFS) was 42 +/- 9.7%. Based on multivariate analysis, two groups showed marked differences in five-year outcome: children with age<10, leukocyte count <100,000/mm3 and day-21 M1 marrow had a more favorable prognosis (14 pts: 100% CR, event free survival [EFS]: 57%, overall survival [OS]: 79%), than the high-risk group (22 patients: 55% CR, EFS: 18%, OS: 27%) (p < 0.005). We also observed a non statistically significant difference (p = 0.14) in outcome between these groups for transplanted patients (5-year DFS: 83 +/- 14% and 33 +/- 15%, respectively)., Conclusion: Age, leukocyte count and early response to treatment defined by the D21 bone marrow response provide an accurate model for outcome prediction. The combination of available tools such as minimal residual disease assessment with determination of these simple factors could be useful for refining indications for BMT in the current era of tyrosine-kinase inhibitor-based therapy.

Background: Sperm banking is a suitable procedure to prevent infertility after cancer therapy in male adolescents. We evaluated the feasibility of semen preservation in 156 adolescents aged between 13 and 20 years and then we assessed fertility outcome after treatment., Methods: Age, urogenital history, indications for cryopreservation, histological diagnosis and semen parameters were recorded. Fertility status after treatment was assessed by a questionnaire addressed to those patients who had utilized sperm storage. Post-treatment semen analysis was performed for 22 patients., Results: Cryopreservation was possible in 88.5% of cases. Azoospermia was detected in 2.6% of the patients at the time of diagnosis. Malignant disease accounted for 84% of our male adolescents. In this type of disease, semen parameters were significantly altered only among patients with metastatic malignant bone tumour. After treatment, nine patients presented azoospermia, five patients achieved pregnancy spontaneously, two achieved it after assisted reproductive technique using fresh ejaculated spermatozoa and one following sperm donation. Three failed with cryopreserved sperm., Conclusions: Semen cryopreservation is possible for most adolescents and, regardless of disease type, may be a means of preserving fertility prior to gonadotoxic treatment that might impair the spermatogenesis process.

Primary germ cell tumors (PGCT) of the central nervous system usually develop in the third ventricle area, and most frequently in the pineal region. The suprasellar region is the second preferential site for development of these tumors which are rarely simultaneously present in these two sites. We report five new cases of PGCT with pineal and suprasellar localizations, which appeared in late puberty in four boys and one girl aged 17-19 years. The clinical picture associated signs of intracranial hypertension, convergence and verticality palsies, diabetes insipidus and pituitary deficiency. Encephalic MRI revealed a double localization. Endocrine tests revealed a particular pattern associating central diabetes insipidus and a hypothalamic-pituitary disconnection syndrome. Following identification of the pathological type of lesions via a neurosurgical approach, treatment was based on a combined method using chemotherapy, radiotherapy and hormone replacement. Based on this treatment, prolonged remissions were obtained with a good quality of life.

According to biologic features, there is a substantial "gray zone" between nodular lymphocyte predominant Hodgkin lymphomas (NLPHLs) (Poppema lymphomas) and T-cell/histiocyte-rich B-cell lymphomas (T/HRBCLs). Transformation from an NLPHL to a T/HRBCL can occur and is associated with a worsening of the prognosis. Here is described a case of a 16-year-old boy who presented with an NLPHL with features of T/HRBCL. Clinical evolution was complicated by 2 relapses leading to autologous and then to allogeneic bone marrow transplantation.

Since neuroblastoma occurs very early in children's lives, it has been hypothesized that pre- and perinatal factors may play a role in its etiology. This study investigated the role of birth characteristics, congenital malformation and maternal reproductive history in neuroblastoma. The data used were generated by the national population-based case-control study, ESCALE, conducted in France in 2003-2004. The mothers of 191 neuroblastoma cases and 1,681 controls, frequency-matched by age and gender, were interviewed by telephone, using a standardized questionnaire, on several factors including pregnancy, medical history, lifestyle, childhood medical conditions and exposures. A positive association between congenital malformation and all neuroblastoma cases was observed [Odds ratio (OR) = 2.2, 95% confidence interval (95% CI): 1.1-4.5]. Congenital malformations were highly associated to neuroblastoma in children aged less than 1 year (OR = 16.8, 95% CI: 3.1-90), while no association was observed in children aged 1 year or more (OR = 1.0, 95% CI: 0.3-2.9). A negative association with a maternal history of spontaneous abortions was also found (OR = 0.6, 95% CI: 0.4-0.9). The results strongly support the hypothesis that congenital anomalies may be associated with neuroblastoma, particularly in infant (less than 1 year of age)., ((c) 2008 Wiley-Liss, Inc.)

Acute lymphoblastic leukemia is the main type of leukemia in children. An infectious etiology has been suspected and the role of the Human herpesvirus-6 (HHV-6) has been suggested. Several studies have tried to establish a link between HHV-6 infections and hematological malignancies, with discordant results. The potential role of HHV-6 in the pathogenesis of pediatric acute lymphoblastic leukemia was investigated. HHV-6 genome copy number was measured by quantitative real-time PCR (RQ-PCR) in bone marrow or peripheral blood samples obtained from 36 children (median age = 4 years) with B acute lymphoblastic leukemia (n = 31) and T acute lymphoblastic leukemia (n = 5) at diagnosis and during complete remission. Positive samples were further characterized to define viral variant, A or B. A total of 24.7% of samples were positive for HHV-6 genome: 13.9% were leukemia samples and 34.1% were complete remission samples. Viral load was low with values lower at diagnosis (median viral copy number = 22.9) than at complete remission (median copy number = 60.1). Among the 17 patients with positive samples, 15 were typed as B-variant whereas 2 could not be typed. These results argue against a role of HHV6 infection in the development of pediatric acute lymphoblastic leukemia. They also suggest that HHV-6 may infect latently bone marrow progenitors but seems not able to infect leukemic cells, raising again the question of the mechanism of virus fusion and entry. This observation shows that a reactivation may be observed during complete remission supporting the possibility of virus reactivation in immunocompromised hosts.

Transitional B cells have been recently identified in human peripheral blood. However, their precise role in human B cell differentiation has not been established. Therefore, besides characterizing them further in the blood of healthy adults and children and cord blood, we used the immune reconstitution after hematopoietic stem cell transplantation (HSCT) model to define their role in human B cell development. Human transitional B cells are reliably identified as CD19(+) CD24(high) CD38(high) lymphocytes and represent approximately 4% of B cells in healthy adult peripheral blood. In contrast, they are abundant in cord blood (near 50% of B cells) and their percentage progressively decreases during infancy. Similarly, after HSCT, all B cells first appearing in peripheral blood are transitional B cells; afterwards, the transitional B cell percentage progressively decreases while the mature naïve B cell proportion rises. Our results now formally demonstrate that transitional B cells are necessary developmental intermediates for human mature B cell generation.

Objective: Beyond to control of cell migration, differentiation and proliferation, the extracellular matrix (ECM) also contributes to invasiveness of human cancers. As the roles of hyaluronan (HA) and collagens in this process are still controversial, we have investigated their involvement in cancer pathogenesis., Materials and Methods: With this aim in view, we developed a three-dimensional matrix, as reticulate HA hydrogel alone or coated with different collagens, in which cells could invade and grow., Results: We show that cancer cells, which were non-invasive in a single HA hydrogel, acquired this capacity in the concomitant presence of type I or III collagens. Both types of ECM compound, HA and collagens, possess the capacity to stimulate production of metalloprotease-2, recognized otherwise as a factor for poor cancer prognosis. HA-provoked cellular invasiveness resulted from CD44-mediated increase in cytosolic [Ca2+] and its subsequent hydrolysis due to ADAM (a disintegrin and metalloprotease) proteolytic activity. Interestingly, this mechanism seemed to be absent in non-invasive cancer cell lines., Conclusion: Furthermore, using basic fibroblast growth factor and stromal cell-derived factor-1alpha, we also show that this three-dimensional reticulate matrix may be considered as a valuable model to study chemokinetic and chemotactic potentials of factors present in tumour stroma.

Background: Daunoxome (DNX) is an encapsulated form of daunorubicin in liposomal vesicles with suggested better pharmacokinetics, pharmacodynamics and lesser cardio toxicity than the free form. Polyethyl glycol asparaginase (PEG-ASPA), a modified form of L-asparaginase, has better activity and lesser immunogenicity than its native molecule., Aim: To evaluate on a compassionate basis, the combination of Daunoxome and PEG-ASPA, as regard to efficacy and toxicity, as a salvage treatment in refractory/relapsed childhood ALL., Methods: The combination of these 2 drugs were used in 9 multiple relapsed or refractory ALL children on the basis of: DNX weekly 100 mg/m2 D1, 8, 15. PEG-ASPA single, 2500IU/m2 dose D15. Vinca alkaloids and corticosteroids were associated., Results: Median hospital stay was 4 days (0-55)., Complications: Neutropenia grade IV n=4, grade III infection n=6, grade II cardiac toxicity n=1, grade III allergy, grade III hemostasis disorders, thrombosis, n=1 respectively. All patients achieved complete remission (CR) except one who died from disease progression. 8 patients were subjected to hematopoietic stem cell transplantatation (HSCT). Two patients of them are alive and well, 4 died from transplant related causes and 2 from disease progression., Conclusion: Salvage treatment containing DNX and PEG-ASPA, of small sample childhood ALL with very advanced disease, is feasible as regard toxicity and response rate allowing to HSCT and possible cure.

The extracellular polysaccharide hyaluronan (HA) controls cell migration, differentiation and proliferation, and contributes to the invasiveness of human cancers. In order to investigate the sensitivity of cancer cells to antimitotic agents, we developed a cross-linked HA hydrogel, a three-dimensional matrix in which cells can invade and grow. We have studied three cell lines (SA87, NCI-H460 and H460M), from primary tumors and metastases, that migrated into the HA hydrogel and proliferated giving rise to clusters and colonies. Concurrently, we studied the growth of these cell lines in a usual monolayer culture system. In these two models, increasing concentrations of doxorubicin and 5-fluorouracil were evaluated for their ability to inhibit tumor cell growth and colony formation. Taken together, our data suggest that the cancer cells were more resistant in the three-dimensional model than in monolayer cell systems. The antimitotic drugs were efficient after 24h of treatment in the monolayer cultures, whereas they were significantly efficient only after one week of incubation in the HA hydrogels. Herein, we show that this cross-linked matrix provides a three-dimensional model particularly appropriate for investigating mechanisms involved in cancer cell line sensitivity to antimitotic drugs.

Neuroblastoma is one of the most common cancers in children. Neuroblastoma differentiation is linked to the presence of the promyelocytic leukemia (PML) protein. Retinoic acid, a powerful differentiation-inducer in vitro, is a potent agent for the treatment of neuroblastoma. Using two different human neuroblastoma cell lines, SH-SY5Y and LA-N-5, we show here that PML protein leads to the formation of nuclear bodies (PML-NB) after only 1 h of retinoic acid treatment and that this formation is mediated by the extracellular signal-regulated kinase (ERK) pathway. Inhibition of protein kinase C also leads to formation of PML-NB via the ERK pathway. Both sumoylation and phosphorylation of PML in an ERK-dependent pathway are also required for formation of PML-NB. Finally, we show that PML-NB formation in neuroblastoma cells is associated with neurite outgrowth. These results support the proposal that the formation of PML-NB is correlated with the differentiation of neuroblastoma cells.

Allogeneic hematopoietic stem-cell transplantation (HSCT) is the only curative treatment for sickle cell disease (SCD); nevertheless, its use has been limited by the risk of transplantation-related mortality (TRM). Between November 1988 and December 2004, 87 consecutive patients with severe SCD ranging from 2 to 22 years of age received transplants in France. Cerebral vasculopathy was the principal indication for transplantation (55 patients). All the patients received grafts from a sibling donor after a myeloablative conditioning regimen (CR). The only change in the CR during the study period was the introduction of antithymocyte globulin (ATG) in March 1992. The rejection rate was 22.6% before the use of ATG but 3% thereafter. With a median follow-up of 6 years (range, 2.0 to 17.9 years), the overall and event-free survival (EFS) rates were 93.1% and 86.1%, respectively. Graft versus host disease (GVHD) was the main cause of TRM. Importantly, cord blood transplant recipients did not develop GVHD. No new ischemic lesions were detected after engraftment, and cerebral velocities were significantly reduced. The outcome improved significantly with time: the EFS rate among the 44 patients receiving transplants after January 2000 was 95.3%. These results indicate that HLA-identical sibling HSCT after myeloablative conditioning with ATG should be considered as a standard of care for SCD children who are at high risk for stroke.

A case-control study was conducted to investigate the role of a familial history of cancer in the etiology of childhood acute leukemia. The history of cancer in the relatives of 472 cases was compared with that of 567 population-based controls. Recruitment was frequency matched on age, sex and region. The familial history of cancer in each child's relatives was reported by the mother in response to a standardized self-administered questionnaire. A familial history of solid tumor in first or second-degree relatives was associated with an increased risk of acute lymphoblastic leukemia (odds ratio (OR)=1.6 [95% confidence interval, 1.2-2.1]), while a familial history of hematopoietic malignancies in first or second-degree relatives was associated with an increased risk of acute myeloid leukemia (OR=4.3 [1.4-13]). The ORs for the histories of cancer increased with the number of relatives with cancer (OR=1.5 [1.1-2.0] for one relative and OR=2.3 [1.3-3.8] for two relatives or more; Ptrend<0.0001). Significant associations between childhood acute leukemia and familial history of genital cancers and brain tumor were also observed (OR=2.7 [1.2-5.8] and OR=10.7 [1.3-86], respectively). This study supports the hypothesis that a familial history of cancer may play a role in the etiology of childhood acute leukemia. It also evidences some specific associations that require further investigation.

Angiogenic factors such as basic fibroblast growth factor (bFGF) or vascular endothelial growth factor (VEGF) were previously studied in childhood acute lymphoblastic leukaemia (ALL) but little is known concerning the anti-angiogenic response in ALL. At diagnosis, the plasma levels of the anti-angiogenic factor endostatin were significantly higher in 33 children with ALL than in controls (median values 17.7 and 7.6 ng/ml, respectively, p=0.0192) but no relationship was observed with plasma bFGF or VEGF levels. The highest levels were observed in patients with an hyperdiploïd karyotype. Expression of mRNA for collagen XVIII/endostatin in lymphoblasts was detected in 19/24 cases but protein secretion was found only in 14/28 supernatants of cultured lymphoblasts. No direct relationship appeared between secretion of endostatin by lymphoblasts and plasma levels. In addition, endostatin levels remained elevated in remission, suggesting that endostatin could have a stromal origin as well. No prognostic value of plasma endostatin could be assessed. In conclusion, the present data indicate that an anti-angiogenic response is observed in some ALL children, but its physiopathological importance remains to be established.

The objective of the study was to assess acute neurotoxicity associated with triple intrathecal therapy (TIT)+/-high-dose methotrexate (HD MTX) in children with acute lymphoblastic leukemia (ALL). 1395 children were enrolled on FRALLE 93 protocol from 1993 to 1999. Lower-risk group (LR, n=182) were randomized to weekly low-dose MTX at 25 mg/m(2)/week (LD MTX, n=81) or HD MTX at 1.5 g/m(2)/2 weeks x 6 (n=77). Intermediate-risk group (IR, n=672) were randomized to LD MTX (n=290) or HD MTX at 8 g/m(2)/2 weeks x 4 (n=316). Higher-risk group (HR, n=541) prednisone-responder patients received LD MTX and cranial radiotherapy. HR group steroid resistant cases were grafted (autologous or allogenic). TIT (MTX, cytarabine and methylprednisolone) was given every 2 weeks during 16-18 weeks and every 3 months during maintenance therapy in LR and IR patients. 52 patients (3.7%) developed neurotoxicity. Isolated seizures: n=15 (1.1%), peripheral and spinal neuropathy: n=17 (1.2%) and encephalopathy: n=20 (1.4%). Age >10 years was significantly associated with neurotoxicity (P=0.01) and use of HD MTX is associated with encephalopathy (P=0.03). Sequels are reported respectively in 60 and 33% of spinal neuropathy and encephalopathy cases. Current strategies tailoring risk of neurological sequels has to be defined.

Fondaparinux is a synthetic pentasaccharide consisting of the minimal sequence of heparin which interacts with antithrombin (AT). It represents a new class of selective factor Xa inhibitors without any antithrombin activity. It has been shown to exhibit potent antithrombotic properties in clinical studies. However, the mechanism of its antithrombotic action has not yet been fully established. In the present study it was shown that fondaparinux, used at pharmacological concentration (500 ng/ml), rendered the clot more susceptible to fibrinolysis induced by t-PA: plasma fibrin clots formed in the presence of fondaparinux and perfused with t-PA were degraded at a faster rate than those formed in the absence of fondaparinux. This fibrinolytic activity of fondaparinux is mainly due to a modification of clot structure characterized by a loose fibrin conformation with less branched fibers and the presence of large pores in comparison to control clots which present a tighter conformation. The difference in fibrin structure was responsible for an increase in clot porosity leading to a better availability of t-PA to the fibrin network. It is related to the decrease in thrombin generation, in an AT-dependent pathway. It was also demonstrated that in the presence of exogenous thrombomodulin, the inhibition of TAFI activation by fondaparinux could contribute, to a lesser extent, to the increased thrombus lysis. The increase in t-PA induced thrombus lysis could contribute to the antithrombotic activity of fondaparinux.