Nimotuzumab and radiotherapy for treatment of newly diagnosed diffuse intrinsic pontine glioma (DIPG): a phase III clinical study.

BACKGROUND: Diffuse intrinsic pontine glioma (DIPG) is a devastating cancer of childhood and adolescence. METHODS: The study included patients between 3 and 20 years with clinically and radiologically confirmed DIPG. Primary endpoint was 6-month progression-free survival (PFS) following administration of nimotuzumab in combination with external beam radiotherapy (RT). Nimotuzumab was administered intravenously at 150 mg/m2 weekly for 12 weeks. Radiotherapy at total dose of 54 Gy was delivered between week 3 and week 9. Response was evaluated based on clinical features and MRI findings according to RECIST criteria at week 12. Thereafter, patients continued to receive nimotuzumab every alternate week until disease progression/unmanageable toxicity. Adverse events (AE) were evaluated according to Common Terminology Criteria for Adverse Events (CTC-AE) Version 3.0 (CTC-AE3). RESULTS: All 42 patients received at least one dose of nimotuzumab in outpatient settings. Two patients had partial response (4.8%), 27 had stable disease (64.3%), 10 had progressive disease (23.8%) and 3 patients (7.1%) could not be evaluated. The objective response rate (ORR) was 4.8%. Median PFS was 5.8 months and median overall survival (OS) was 9.4 months. Most common drug-related AEs were alopecia (14.3%), vomiting, headache and radiation skin injury (7.1% each). Therapy-related serious adverse events (SAEs) were intra-tumoral bleeding and acute respiratory failure, which were difficult to distinguish from effects of tumor progression. CONCLUSIONS: Concomitant treatment with RT and nimotuzumab was feasible in an outpatient setting. The PFS and OS were comparable to results achieved with RT and intensive chemotherapy in hospitalized setting.

Laparoscopic Adrenalectomy is Feasible for Suspected Adrenal Tumors in Children Younger than 24 Months of Age - But is it Always Justified?

INTRODUCTION: Tumors of the adrenal gland are rare in children younger than 24 months of age. While neuroblastomas are most important in this age group, adrenal hemorrhage and other tumors are sometimes difficult to distinguish. Harvesting biopsies is mandatory in these young patients to obtain information on molecular markers, namely, MYCN and 1p deletion. PATIENTS: Between 03/2012 and 10/2013, 11 patients younger than 24 months of age with suspicious adrenal tumors were operated on laparoscopically. METHODS: The diagnostic workup was coordinated by our pediatric oncologists according to the terms of the NB2004 trial protocol. RESULTS: 9 out of 11 had a diagnosis of neuroblastoma, the others were adenoma respective complete necrosis of the adrenal gland. All of the neuroblastomas were negative for both MYCN amplification and 1p deletion. A complete resection was successful in 9 out of 11 cases. 3 complications occurred, 1 major and 2 minor. DISCUSSION AND CONCLUSION: Behind the recognition that laparoscopic adrenalectomy is technically feasible, the fact that all neuroblastomas were negative for MYCN amplification and 1p deletion raises the issue of whether biopsy is mandatory for risk stratification in this age group.

MiRNome and transcriptome aided pathway analysis in human regulatory T cells.

Owing to their manifold immune regulatory functions, regulatory T cells (Treg) have received tremendous interest as targets for therapeutic intervention of diverse immunological pathologies or cancer. Directed manipulation of Treg will only be achievable with extensive knowledge about the intrinsic programs that define their regulatory function. We simultaneously analyzed miR and mRNA transcript levels in resting and activated human Treg cells in comparison with non-regulatory conventional T cells (Tcon). Based on experimentally validated miR-target information, both transcript levels were integrated into a comprehensive pathway analysis. This strategy revealed characteristic signal transduction pathways involved in Treg biology such as T-cell receptor-, Toll-like receptor-, transforming growth factor-ß-, JAK/STAT (Janus kinase/signal transducers and activators of transcription)- and mammalian target of rapamycin signaling, and allowed for the prediction of specific pathway activities on the basis of miR and mRNA transcript levels in a probabilistic manner. These data encourage new concepts for targeted control of Treg cell effector functions.

[Pilot project of a pediatric antibiotic stewardship initiative at the Hauner children's hospital]. / Pilotprojekt einer pädiatrischen Antibiotic-Stewardship-Initiative am Dr. von Haunerschen Kinderspital - neue Wege der pädiatrischen Infektiologie.

The steady increase in antimicrobial resistance is of growing concern in healthcare. Antibiotic Stewardship [ABS] Strategies are important tools to control antibiotic use and -prevent antimicrobial resistance. An increasing number of institutions are developing ABS initiatives also in pediatrics. However, few data are available assessing the implementation and efficiency of these pediatric ABS programs.At the Dr. von Hauner Children's Hospital, Ludwig-Maximilian University, a tertiary care pediatric reference center, a pediatric ABS Team has been implemented. Key structural elements were the same as for adult patients, but antimicrobials agents selected for monitoring and appropriate clinical endpoints are different in pediatrics.Key features were: 1. prospective-audit with feedback and formulary restriction and 2. pre-authorization (also referred to as prior approval). The ABS team consisted of one pediatric infectious disease specialist, one clinical fellow in pediatric infectious diseases, and one clinical pharmacist with training in infectious diseases.With the implementation of a pediatric ABS strategy we could significantly influence antimicrobial consumption in our hospital. Cost-savings are estimated to be above 330 000 € per year, and concomitantly the use of broad-spectrum antibiotics and antifungal compounds was significantly reduced.Antibiotic Stewardship [ABS] Strategies may be an effective tool to control antibiotic use in the setting of a large tertiary pediatric teaching hospital. A national guideline for ABS initiatives may help to further improve rational use of antibiotics in the hospital setting.

Free asymmetric dimethylarginine (ADMA) is low in children and adolescents with classical phenylketonuria (PKU).

INTRODUCTION: Free asymmetric dimethylarginine (ADMA) is a competitive inhibitor of the nitric oxide synthases (NOS). Suppression of nitric oxide (NO) synthesis increases the risk of atherosclerosis. Nevertheless, in the condition of oxidative stress, NOS blockade by ADMA may exert protective effects. Protein metabolism is altered in patients with phenylketonuria (PKU) on dietary treatment and as shown recently, oxidative stress is high in PKU. Since free ADMA concentrations are determined by both protein metabolism and oxidative stress we hypothesized, that free ADMA levels may be elevated in PKU patients. DESIGN: Sixteen patientswith PKU on dietary treatment (mean age 10.1 ± 5.2 yrs), and 91 healthy children (mean age 11.6 ± 3.7 yrs) participated in a cross sectional study. RESULTS: ADMA, total homocysteine (tHcy) and blood glucose were lower and the L-arginine/ADMA ratio was higher in PKU patients compared to controls. No significant correlation was present between phenylalanine (Phe) concentrations, protein intake, and lipid profile, history of cardiovascular disease or ADMA. DISCUSSION: In contrast to our hypothesis, ADMAwas lower and the L-arginine/ADMA ratio was higher in PKU patients. Therefore, in PKU patients, the regulating function of ADMA on NO synthesis is altered and may thus contribute to oxidative stress.

Exchange bias and domain evolution at 10 nm scales.

For a fixed 2 µm×2 µm area of a Co/Pt-CoO perpendicular exchange bias system we image the ferromagnetic (FM) domains for various applied fields with 10-nm resolution by magnetic force microscopy (MFM). Using quantitative MFM we measure the local areal density of pinned uncompensated spins (pinUCS) in the antiferromagnetic (AFM) CoO layer and correlate the FM domain structure with the UCS density. Larger applied fields drive the receding domains to areas of proportionally higher pinUCS aligned antiparallel to FM moments. The data confirm that the evolution of the FM domains is determined by the pinUCS in the AFM layer, and also present examples of frustration in the system.

Successful long-term correction of autosomal recessive hyper-IgE syndrome due to DOCK8 deficiency by hematopoietic stem cell transplantation.

Autosomal dominant hyper-IgE syndrome (AD-HIES), characterised by eczema, increased susceptibility to skin and lung infections, elevated IgE and skeletal abnormalities is associated with heterozygous STAT3 mutations. The autosomal recessive variant (AR-HIES) has similar immunological findings but mainly lacks extraimmune manifestations. Several AR-HIES patients have recently been shown to harbour mutations in the gene for dedicator of cytokinesis 8 (DOCK8). Here, we present the long-term outcome of a girl having received a hematopoietic stem cell graft for an at that time genetically undefined combined immunodeficiency associated with severe eczema, multiple food allergies, excessively elevated serum IgE levels and eosinophilia. She was recently found to carry a homozygous nonsense mutation in the DOCK8 gene. HSCT resulted in complete immunological correction, even though mixed donor chimerism occurred. Clinically, the outcome was characterised by disappearance of skin manifestations and severe infections, improvement of pulmonary function and constant decline of IgE levels. Outcome in untransplanted DOCK8 deficient patients is poor because of frequent life-threatening infections, CNS bleeding and infarction, and increased susceptibility to malignancy. This argues for early curative therapeutic approaches, supported by this report of successful long-term outcome after HSCT.

A novel FIP1L1-PDGFRA mutant destabilizing the inactive conformation of the kinase domain in chronic eosinophilic leukemia/hypereosinophilic syndrome.

BACKGROUND: The Fip1-like-1-platelet-derived growth factor receptor alpha (FIP1L1-PDGFRA) gene fusion is a common cause of chronic eosinophilic leukemia (CEL)/hypereosinophilic syndrome (HES), and patients suffering from this particular subgroup of CEL/HES respond to low-dose imatinib therapy. However, some patients may develop imatinib resistance because of an acquired T674I mutation, which is believed to prevent drug binding through steric hindrance. METHODS: In an imatinib resistant FIP1L1-PDGFRA positive patient, we analyzed the molecular structure of the fusion gene and analyzed the effect of several kinase inhibitors on FIP1L1-PDGFRA-mediated proliferative responses in vitro. RESULTS: Sequencing of the FIP1L1-PDGFRA fusion gene revealed the occurrence of a S601P mutation, which is located within the nucleotide binding loop. In agreement with the clinical observations, imatinib did not inhibit the proliferation of S601P mutant FIP1L1-PDGFRA-transduced Ba/F3 cells. Moreover, sorafenib, which has been described to inhibit T674I mutant FIP1L1-PDGFRA, failed to block S601P mutant FIP1L1-PDGFRA. Structural modeling revealed that the newly identified S601P mutated form of PDGFRA destabilizes the inactive conformation of the kinase domain that is necessary to bind imatinib as well as sorafenib. CONCLUSIONS: We identified a novel mutation in FIP1L1-PDGFRA resulting in both imatinib and sorafenib resistance. The identification of novel drug-resistant FIP1L1-PDGFRA variants may help to develop the next generation of target-directed compounds for CEL/HES and other leukemias.

Overexpression of cyclin D1, D3, and p21 in an infantile renal carcinoma with Xp11.2 TFE3-gene fusion.

Renal carcinomas harboring the TFE-3 translocation are rare and occur predominately in children and adolescents. Here, we report a case of infantile renal carcinoma with TFE3 translocation and show that the cell cycle is deregulated in this type of carcinoma. It is characterized by nuclear accumulation of cyclin D1 and D3 in combination with high levels of cyclin-dependent kinase inhibitor p21Cip1/Waf1 but without accumulation of p53, p16INK4a, or mdm2. The combined overexpression of p21, cyclin D1, and cyclin D3 was found exclusively in this type but not in other, more common types of renal carcinoma/oncocytoma (n=27). These results further underscore that renal carcinomas with Xp11. 2 translocations/TFE3-gene fusion represent a special type of renal neoplasm showing deregulation of specific cell cycle components. The analysis of further cases has to prove whether the derangement of the cell cycle is uniform and correlates with the specific type of molecular genetic derangement.

[Digital ischemia of a patient with undifferentiated large cell lung cancer]. / Digitale Ischämien bei einer Patientin mit grosszelligem Lungenkarzinom.

A Raynaud's phenomenon with acral ischemia till necrosis is a rare form of a paraneoplasia. We report about a woman with a metastatic lung cancer, who was admitted because of pain in her left hand with necrosis of the fingertips and of the fifth right toe. We started a treatment with the intravenous vasodilator Iloprost, but the necroses progressed to gangrene. The course of a paraneoplastic syndrome is often determined by the underlying malignoma and if the antineoplastic treatment is ineffective, the chances to treat the paraneoplasia may be limited.

A human immunodeficiency syndrome caused by mutations in CARMIL2.

Human T-cell function is dependent on T-cell antigen receptor (TCR) and co-signalling as evidenced by immunodeficiencies affecting TCR-dependent signalling pathways. Here, we show four human patients with EBV+ disseminated smooth muscle tumours that carry two homozygous loss-of-function mutations in the CARMIL2 (RLTPR) gene encoding the capping protein regulator and myosin 1 linker 2. These patients lack regulatory T cells without evidence of organ-specific autoimmunity, and have defective CD28 co-signalling associated with impaired T-cell activation, differentiation and function, as well as perturbed cytoskeletal organization associated with T-cell polarity and migration disorders. Human CARMIL2-deficiency is therefore an autosomal recessive primary immunodeficiency disorder associated with defective CD28-mediated TCR co-signalling and impaired cytoskeletal dynamics.

Bone marrow Th2 cytokine expression as predictor for relapse in childhood acute lymphoblastic leukemia (ALL).

The immunological environment of leukemic blasts in the bone marrow might play a decisive role in determining an individual's risk for relapse. In order to identify potential predictors of relapse and to elucidate the mechanisms of immune control of leukemic blasts we examined the expression of cytokines, costimulatory molecules and members of the TNF family in leukemic marrow samples in a prospective study. Samples from 49 consecutive pediatric patients with B cell precursor acute lymphocytic leukemia (BCP ALL) were analyzed by semiquantitative RT-PCR. We identified interleukin (IL)-10 expression as a significant adverse prognostic indicator in childhood BCP-ALL. The event free survival (EFS) of patients expressing IL-10 mRNA in high quantity was significantly lower compared with patients expressing low IL-10 mRNA. Taqman RT-PCR of sorted cell populations showed that IL-10 mRNA was synthetized almost exclusively by NK or T cells. In addition, we found an increased expression of IL-1, IL-4, CD86 and VEGF mRNA in patients with late relapses. Possibly, ALL cells mediate a Th2 shift through increased expression of CD86 and thereby influence the individual relapse risk. These findings emphasize the role of the immune system for the outcome of childhood ALL.

Effects of soluble TNF receptor II (sTNF-RII), IL-1 receptor antagonist (IL-1ra), tumor load and hypermetabolism on malnutrition in children with acute leukemia.

OBJECTIVE: Soluble tumor necrosis factor receptor II (sTNF-RII) and interleukin-1 receptor antagonist (IL-1ra) might modulate nutritional status in acute leukemia since they are inhibitors of tumor necrosis factor-alpha and interleukin-1 that can induce tissue wasting. On the other hand, tumor load and hypermetabolism may induce malnutrition. We determined whether serum levels of sTNF-RII and IL-1ra are upregulated to prevent overt malnutrition and whether tumor load and hypermetabolism induce overt malnutrition. METHODS: We examined 31 children with newly diagnosed acute leukemia and correlated sTNF-RII, IL-1ra, tumor load and energy expenditure to anthropometric characteristics (weight, weight for height, height, body mass index, fat free mass) and serum protein concentrations (albumin, transferrin, prealbumin). As controls, 68 healthy children were examined for anthropometric characteristics; 33 healthy controls were included for cytokine analysis and biochemical indices. RESULTS: We found no correlations between sTNF-RII, IL-1ra, tumor load and energy expenditure and anthropometric characteristics or protein concentrations. Mean sTNF-RII level was significantly, mean IL-1ra level slightly increased (223% and 113% of the controls). 29% of the children had a high tumor load (> 100.000/microl white blood cells) and 53% had hypermetabolism (resting energy expenditure > 110% of predicted). Anthropometric characteristics were similar to those in controls, however, serum protein concentrations were decreased. CONCLUSION: sTNF-RII and IL-1ra are upregulated in children with leukemia and may therefore prevent overt malnutrition. Tumor load and hypermetabolism do not induce overt malnutrition. The children presented with an early stage of malnutrition as evidenced by low serum protein concentrations but normal anthropometric characteristics.

Differential tropism of HIV-1 isolates for distinct thymocyte subsets in vitro.

OBJECTIVE: Understanding the interaction between HIV and developing thymocytes is crucial in determining how HIV infection perturbs the immune system. We determined which thymocyte subsets can harbor and express HIV. DESIGN: HIV expression in mature and immature thymocytes obtained from surgical specimens from non-infected children was determined after in vitro infection with the syncytium-inducing, cytopathic NL4-3 and the non-syncytium-inducing, relatively noncytopathic JR-CSF isolates. METHODS: Intracellular staining for the HIV p24gag antigen was combined with cell surface phenotyping to determine thymocyte subsets expressing HIV. Infection was quantitated by polymerase chain reaction on sorted subsets. RESULTS: NL4-3 replicated faster and to higher titers and caused a more severe decrease of all CD4-bearing thymocytes than did JR-CSF. In addition, both immature CD1+ and mature CD1-thymocytes expressed NL4-3, whereas only mature CD1-cells expressed JR-CSF. The tropism of NL4-3 for these immature cells suggests a mechanism for a more profound impact on T-cell maturation than that seen with JR-CSF. We also found that thymocytes lacking cell surface CD4 (CD4-CD8- and CD4-CD8+ subsets) expressed virus with either isolate late in infection, when viral levels were high. The CD4-CD8- cells expressing HIV were mature CD3bright T-cell receptor (TCR) alpha/beta bright cells. CONCLUSIONS: These results show that NL4-3 can be expressed by thymocytes at immature and mature stages of differentiation and cause severe loss of CD4+ cells. Thus, tropism of a virus for immature cells can affect the capability of the thymus to produce new T lymphocytes leading to a greater impact on development and functions of the immune system. It is proposed that this in vitro model can be used to study pathogenic mechanisms in the thymus.

Atypical apoptotic cell death induced in L929 targets by exposure to tumor necrosis factor.

The mechanism by which tumor necrosis factor (TNF) induces cytotoxicity of murine fibroblasts was investigated. Electrophoresis of DNA extracted from TNF-treated L929 targets showed fragmentation of DNA into a ladder-like pattern, typical of cells dying by apoptosis. Morphologic analysis also indicated apoptotic cell death, demonstrating clumping and crescentic condensation of chromatin. In contrast, chromatin condensation and ladder-like DNA fragmentation were not detected in L929 targets dying by necrosis from exposure to heat, repeated cycles of freeze-thaw, and sodium azide. Chromatin condensation was an early event, detected as early as 6 h of incubation. However, DNA fragmentation (assayed by double-stranded fragmentation assay and gel electrophoresis), as well as the apoptotic changes detected by Hoechst fluorescence, both occurred later and did not precede TNF cytotoxicity (membrane permeabilization detected by trypan blue or propidium iodide staining). This atypical pattern of apoptosis was a characteristic of L929 target cells rather than a generalized cytotoxic response to TNF because TNF-treated squamous cancer cells showed typical features of apoptosis (DNA fragmentation before cytotoxicity) and etoposide-treated L929 cells demonstrated the same atypical kinetics as TNF-treated cells. Zinc significantly inhibited TNF cytotoxicity as well as DNA fragmentation of L929. However, because DNA fragmentation occurred belatedly in TNF-treated targets, lagging behind cytotoxicity, the protection by zinc against TNF appears mediated by events that occur before the ultimate endonuclease-induced cleavage of DNA into small fragments.

A novel B cell stimulation/proliferation assay using simultaneous flow cytometric detection of cell surface markers and DNA content.

Assessment of the specific B cell proliferative response by thymidine incorporation following polyclonal stimulation (e.g. with pokeweed mitogen or B cell growth factor) is problematic whenever the proportion of B cells in a particular sample is low as in blood samples. Here we describe a simple assay consisting of identifying the cultured B cells with anti-CD19/CD20 fluorescein-conjugated antibody and simultaneously using propidium iodide DNA staining to determine the percent of S/G2/M phase cells among the gated B cells. This assay can be used to determine B cell responsiveness even in individuals with very low blood B cell counts (e.g., in recipients of bone marrow transplant), does not require laborious B cell purifications and does not involve radiation hazard.

Measurement of lymphocyte subset proliferation by three-color immunofluorescence and DNA flow cytometry.

We developed a method for simultaneous flow cytometric analysis of three-color immunofluorescence and DNA content. We show here that staining with 7-amino-actinomycin D (7-AAD) at 10 microg/ml using a phosphate-citrate buffer at low pH containing saponin for cell membrane permeabilization yields good resolution DNA histograms with low coefficients of variation. Furthermore, light scatter properties of cells are preserved after permeabilization; this permits gating on cell populations that differ in scatter signals on the flow cytometer. Because of the low pH of the phosphate-citrate staining buffer, Alexa488, a pH-independent green-fluorescent fluorochrome is used instead of fluorescein-isothiocyanate (FITC) for cell surface staining in combination with phycoerythrin (PE) and with allophycocyanin (APC) which are both pH insensitive. Removal of 7-AAD after staining and replacing it with non-fluorescent actinomycin D (AD) retains DNA staining and allows detection of Alexa488, PE and APC cell surface immunofluorescence without interference from fluorescent 7-AAD in solution for clear identification of cell subpopulations even after prolonged stimulation in culture. Thus, using a four-color benchtop flow cytometer, measurement of Alexa488, PE and APC three-color immunofluorescence can be combined with 7-AAD DNA content analysis. Furthermore, we demonstrate that sample storage overnight without fixation for later analysis on the flow cytometer is possible without compromising results. Application of the method to the assessment of the differential proliferative responses of lymphocyte subsets of human peripheral blood mononuclear cells (PBMC) that were costimulated with CD3 and with CD28.2 is presented.

A rapid method for measuring apoptosis and dual-color immunofluorescence by single laser flow cytometry.

A sensitive method for quantification of cells undergoing apoptosis that permits the simultaneous measurement of dual-color cell surface immunofluorescence is presented. Unfixed cells are stained with 7-amino-actinomycin D (7-AAD) for discrimination of live from early apoptotic cells and from cells which have lost membrane integrity (late apoptotic or necrotic, dead cells). Owing to its spectral characteristics 7-AAD can be combined with fluorescein-isothiocyanate (FITC) and phycoerythrin (PE) cell surface staining. After staining, the samples can be treated with paraformaldehyde (PF) solution to eliminate the risk for exposure of laboratory personnel to biohazardous agents and to preserve the cells through fixation for later analysis on the flow cytometer. The value of the method is shown on the measurement of apoptosis in human thymocytes and in human peripheral blood mononuclear cells (PBMC) exposed to various inducers of active cell death. The method is validated by fluorescent activated cell sorting in combination with morphologic examination of the sorted cells. The technique we are presenting is particularly valuable in a clinical setting because it allows rapid multiparameter analysis of apoptosis in combination with cell surface phenotype on biohazardous samples with single laser instrumentation.