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Supplementary Figure 2 from A Sensitized RNA Interference Screen Identifies a Novel Role for the PI3K p110γ Isoform in Medulloblastoma Cell Proliferation and Chemoresistance

Supplementary Figure 1 from A Sensitized RNA Interference Screen Identifies a Novel Role for the PI3K p110γ Isoform in Medulloblastoma Cell Proliferation and Chemoresistance

Supplementary Figure 3 from A Sensitized RNA Interference Screen Identifies a Novel Role for the PI3K p110γ Isoform in Medulloblastoma Cell Proliferation and Chemoresistance

Supplementary Table 1 from A Sensitized RNA Interference Screen Identifies a Novel Role for the PI3K p110γ Isoform in Medulloblastoma Cell Proliferation and Chemoresistance

Supplementary Figure 4 from A Sensitized RNA Interference Screen Identifies a Novel Role for the PI3K p110γ Isoform in Medulloblastoma Cell Proliferation and Chemoresistance

The quassinoid analogue NBT-272 has been reported to inhibit MYC, thus warranting a further effort 7to better understand its preclinical properties in models of embryonal tumors (ET), a family of childhood malignancies sharing relevant biological and genetic features such as deregulated expression of MYC oncogenes. In our study, NBT-272 displayed a strong antiproliferative activity in vitro that resulted from the combination of diverse biological effects, ranging from G1/S arrest of the cell cycle to apoptosis and autophagy. The compound prevented the full activation of both eukaryotic translation initiation factor 4E (eIF4E) and its binding protein 4EBP-1, regulating cap-dependent protein translation. Interestingly, all responses induced by NBT-272 in ET could be attributed to interference with 2 main proproliferative signaling pathways, that is, the AKT and the MEK/extracellular signal-regulated kinase pathways. These findings also suggested that the depleting effect of NBT-272 on MYC protein expression occurred via indirect mechanisms, rather than selective inhibition. Finally, the ability of NBT-272 to arrest tumor growth in a xenograft model of neuroblastoma plays a role in the strong antitumor activity of this compound, both in vitro and in vivo, with its potential to target cell-survival pathways that are relevant for the development and progression of ET. Mol Cancer Ther; 9(12); 3145–57. ©2010 AACR.

Supplementary Figures 1-4 from Disabling c-Myc in Childhood Medulloblastoma and Atypical Teratoid/Rhabdoid Tumor Cells by the Potent G-Quadruplex Interactive Agent S2T1-6OTD

We investigated here the effects of S2T1-6OTD, a novel telomestatin derivative that is synthesized to target G-quadruplex–forming DNA sequences, on a representative panel of human medulloblastoma (MB) and atypical teratoid/rhabdoid (AT/RT) childhood brain cancer cell lines. S2T1-6OTD proved to be a potent c-Myc inhibitor through its high-affinity physical interaction with the G-quadruplex structure in the c-Myc promoter. Treatment with S2T1-6OTD reduced the mRNA and protein expressions of c-Myc and hTERT, which is transcriptionally regulated by c-Myc, and decreased the activities of both genes. In remarkable contrast to control cells, short-term (72-hour) treatment with S2T1-6OTD resulted in a dose- and time-dependent antiproliferative effect in all MB and AT/RT brain tumor cell lines tested (IC50, 0.25–0.39 μmol/L). Under conditions where inhibition of both proliferation and c-Myc activity was observed, S2T1-6OTD treatment decreased the protein expression of the cell cycle activator cyclin-dependent kinase 2 and induced cell cycle arrest. Long-term treatment (5 weeks) with nontoxic concentrations of S2T1-6OTD resulted in a time-dependent (mainly c-Myc–dependent) telomere shortening. This was accompanied by cell growth arrest starting on day 28 followed by cell senescence and induction of apoptosis on day 35 in all of the five cell lines investigated. On in vivo animal testing, S2T1-6OTD may well represent a novel therapeutic strategy for childhood brain tumors. Mol Cancer Ther; 9(1); 167–79

Purpose: The phosphoinositide 3-kinase (PI3K)/Akt pathway is frequently activated in human cancer and plays a crucial role in neuroblastoma biology. We were interested in gaining further insight into the potential of targeting PI3K/Akt signaling as a novel antiproliferative approach in neuroblastoma.Experimental Design: The expression pattern and functions of class IA PI3K isoforms were investigated in tumor samples and cell lines. Effects on cell survival and downstream signaling were analyzed following down-regulation of p110α or p110δ in SH-SY5Y and LA-N-1 cells by means of RNA interference.Results: Overexpression of the catalytic p110δ and regulatory p85α isoforms was detected in a panel of primary neuroblastoma samples and cell lines, compared with normal adrenal gland tissue. Although down-regulation of either p110α or p110δ led to impaired cell growth, reduced expression of p110δ also had a selective effect on the survival of SH-SY5Y cells. Decreased levels of p110δ were found to induce apoptosis and lead to lower expression levels of antiapoptotic Bcl-2 family proteins. SH-SY5Y cells with decreased p110δ levels also displayed reduced activation of ribosomal protein S6 kinase in response to stimulation with epidermal growth factor and insulin-like growth factor-I.Conclusions: Together, our data reveal a novel function of p110δ in neuroblastoma growth and survival.

Supplementary Data from The Quassinoid Derivative NBT-272 Targets Both the AKT and ERK Signaling Pathways in Embryonal Tumors

Supplementary Methods, Figure Legends 1-4 from Disabling c-Myc in Childhood Medulloblastoma and Atypical Teratoid/Rhabdoid Tumor Cells by the Potent G-Quadruplex Interactive Agent S2T1-6OTD

Supplementary Figures S1-S2 from Targeting the Phosphoinositide 3-Kinase Isoform p110δ Impairs Growth and Survival in Neuroblastoma Cells

The global food production for the worldwide population mainly depends on the huge contributions of the agricultural sector. The cultivated crops of foods need various elements or nutrients to complete their growth, and these are indirectly consumed by humans. During this production, several environmental constraints or stresses may cause losses in the global agricultural production. These obstacles may include abiotic and biotic stresses, which have already been studied in both individual and combined cases. However, there are very few studies on multiple stresses. On the basis of the myriad benefits of nanotechnology in agriculture, nanofertilizers (or nanonutrients) have become promising tools for agricultural sustainability. Nanofertilizers are also the proper solution to overcoming the environmental and health problems that can result from conventional fertilizers. The role of nanofertilizers has increased, especially under different environmental stresses, which can include individual, combined, and multiple stresses. The stresses are most commonly the result of nature; however, studies are still needed on the different stress levels. Nanofertilizers can play a crucial role in supporting cultivated plants under stress and in improving the plant yield, both quantitatively and qualitatively. Similar to other biological issues, many open-ended questions still require further investigation: Is the right time and era for nanofertilizers in agriculture? Will the nanofertilizers be the dominant source of nutrients in modern agriculture? Are nanofertilizers, and particularly biological synthesized ones, the magic solution for sustainable agriculture? What are the expected damages of multiple stresses on plants?

High messenger RNA (mRNA) expression of the tropomyosin receptor kinase C gene (TrkC) has been associated with favorable survival in medulloblastoma patients. Untested is whether it plays a role through modulating the response to therapy or whether it might be a surrogate marker for a favorable molecular subgroup. The medulloblastoma-derived cell line DAOY was stably transfected to overexpress TrkC (clone DAOY-TrkC) and compared to a control (clone DAOY-EV, empty vector transfected). Cell viability (MTS assay) was tested after irradiation or incubation with chemotherapeutic drugs. Neuroradiologic response to postoperative chemotherapy or craniospinal irradiation (CSI) of medulloblastoma patients aged 3–21 years with postoperative residual disease treated within the consecutive trials HIT’91/HIT2000 was compared to TrkC mRNA expression in their tumor samples. Five well-characterized independent expression-profiling studies covering together 686 medulloblastoma patients were analyzed for TrkC levels according to the molecular subgroups. Cell viability of DAOY-TrkC compared to DAOY-EV was not different after exposure to increasing doses of irradiation, cisplatin, etoposide, or vincristine. While TrkC mRNA expression tended to be higher in non-responders (n = 5/19) to postoperative CSI (p = 0.03, ratio 15.5, 95% CI 9–267), this was the case in responders (n = 23/43) to chemotherapy (p = 0.04, ratio 6.1, 95% CI 1.1–35), both analyzed with Mann–Whitney U test (not significant after Bonferroni adjustment). The highest TrkC mRNA levels were found in the SHH subgroup across all expression-profiling studies. High TrkC mRNA expression appears to be frequent in the SHH subgroup and seems not to have a major effect on therapy responsiveness in medulloblastoma patients.

Blockchain is a distributed secure ledger that eliminates the need for centralized authority to store data. The centralized approach has several limitations as it is a Single-Point-of-Failure and a third-party might be needed. Blockchain, on the other hand, provides decentralized, secure and trustless framework that eliminates the need for a third party and enhances fault tolerance. In this paper, we investigate the potentials of customizing the behavior of Blockchain network based on the applications' requirements. In particular, we conduct several experiments to evaluate the performance of the Hyperledger Fabric (HLF) - a permissioned blockchain framework. Seven different scenarios were tested to depict the Blockchain behavior in terms of end-to-end transaction latency and network throughput. Moreover, in these scenarios, the impact of different parameters, such as the batch-timeout, batch size, and number of endorsing peers, has been studied. 2020 IEEE. Qatar University Scopus

Item does not contain fulltext Primitive neuroectodermal tumors of the central nervous system (CNS-PNETs) are highly aggressive, poorly differentiated embryonal tumors occurring predominantly in young children but also affecting adolescents and adults. Herein, we demonstrate that a significant proportion of institutionally diagnosed CNS-PNETs display molecular profiles indistinguishable from those of various other well-defined CNS tumor entities, facilitating diagnosis and appropriate therapy for patients with these tumors. From the remaining fraction of CNS-PNETs, we identify four new CNS tumor entities, each associated with a recurrent genetic alteration and distinct histopathological and clinical features. These new molecular entities, designated "CNS neuroblastoma with FOXR2 activation (CNS NB-FOXR2)," "CNS Ewing sarcoma family tumor with CIC alteration (CNS EFT-CIC)," "CNS high-grade neuroepithelial tumor with MN1 alteration (CNS HGNET-MN1)," and "CNS high-grade neuroepithelial tumor with BCOR alteration (CNS HGNET-BCOR)," will enable meaningful clinical trials and the development of therapeutic strategies for patients affected by poorly differentiated CNS tumors.

Cerebrospinal fluid (CSF) is a readily reachable body fluid that is reflective of the underlying pathological state of the central nervous system (CNS). Hence it has been targeted for biomarker discovery for a variety of neurological disorders. CSF is also the major route for seeding metastases of CNS malignancies and its analysis could be informative for diagnosis and risk stratification of brain cancers. Recently, modern high-throughput, microRNAs (miRNAs) measuring technology has enabled sensitive detection of distinct miRNAs that are bio-chemicallystable in the CSF and can distinguish between different types of CNS cancers. Owing to the fact that a CSF specimen can be obtained with relative ease, analysis of CSF miRNAs could be a promising contribution to clinical practice. In this review, we examine the current scientific knowledge on tumor associated CSF miRNAs that could guide diagnosis of different brain cancer types, or could be helpful in predicting disease progression and therapy response. Finally, we highlight their potential applications clinically as biomarkers and discuss limitations.

The amount of raw data related to electricity consumption is increasing rapidly with the increase of construction sites, population and Qatar preparation for 2022 world cup. By this increase, managers will find difficulties in studying the data and keeping track of the consumption. Thus, taking actions and future planning will be a hard task and the decisions taken might not be beneficial because of the miss understanding of data. In this project, a customized web application is developed to visualize the data on an interactive map. The idea behind the project is to help decision makers to take actions in an efficient and easy way based on the data visualized thus, it supports Qatar's 2030 vision for saving time and electricity. Instead of reading big tables with huge incomprehensible numbers, the application easily visualizes the average consumption on the map. It also provides different chart types to help the user in comparing the data and consequently take the right decision. The rapid increase of data challenges the ability of using such data in decision-making, the challenge also extends to the ability of avoiding the risk of getting lost in these big numbers. Reading such data and trying to analyze it could be wasteful in terms of time and money. Moreover, it could cut down industrial and scientific opportunities. The current solution in Qatar for electric consumption analysis is using Microsoft Excel. The stakeholders only use professional software for operational purposes, but not for analyzing the data. As a result, they are going to see what they asked for only and they would waste any opportunity for deeper insight into these data. Visual analytics is a powerful tool to visualize and transparent processes to provide a means of communicating about them rather than providing results. Data visualization is an effective tool for communication regardless of the communicators’ expertise. It is also viewed as an important analytical tool for effective research communication. It is not limited to the display of raw data sets, but rather all static and interactive visual representations of research data, which may include interactive charts, queries, etc. Combining the visualization aspect with the analytics of big data will significantly help resolving the problem of reading the electricity consumption data. One of the project's goals is to improve the readability of data insights and unlock the ultimate power of data visualization; the data presentation element is where alternative representations will be used to test the persuasive power of visualization. The project aims to make data understandable using data visualization techniques. It provides several features such as an interactive map that indicates the average consumption. The zooming levels are divided into three levels: 1) The Whole Country 2) Municipalities 3) Areas level. In addition, the data is visualized using different graph types: line graphs, pie charts, bar charts and others. This helps the managers and decision makers to effectively analyze the data and compare between different areas and the average consumption through years. Furthermore, it provides different utilities such as emailing the results, printing, saving and showing the table.

The amount of raw data related to electricity companies is increasing rapidly with the increase of construction sites, population and Qatar preparation for 2022 world cup. A question arises from this situation is: How can top level managers keep track of the consumption and plan ahead for the future? The solution is a customized web application that provides an easy way for visualizing the electricity consumption in Qatar. The research aims to help the top-level managers in understanding Qatar's consumption data set to take actions and save for future resources using the proposed software. Our goal is to improve the readability of data insights and unlock the ultimate power of data visualization. 1 2017 IEEE. The authors would like to thank Undergraduate Research Experience Program (UREP) project number UREP19-108-1-012 for funding this project.In-addition to KINDI Center for Computing Research under Qatar University for providing us with workspace and laptops for testing. Scopus

Embryonal tumors of the central nervous system represent a heterogeneous group of childhood cancers with an unknown pathogenesis; diagnosis, on the basis of histological appearance alone, is controversial and patients’ response to therapy is difficult to predict. They encompass medulloblastoma, atypical teratoid/rhabdoid tumors and a group of primitive neuroectodermal tumors. All are aggressive tumors with the tendency to disseminate throughout the central nervous system. The large amount of genomic and molecular data generated over the last 5–10 years encourages optimism that new molecular targets will soon improve outcomes. Recent neurobiological studies have uncovered the key role of microRNAs (miRNAs) in embryonal tumors biology and their potential use as biomarkers is increasingly being recognized and investigated. However the successful use of microRNAs as reliable biomarkers for the detection and management of pediatric brain tumors represents a substantial challenge. This review debates the importance of miRNAs in the biology of central nervous systemembryonal tumors focusing on medulloblastoma and atypical teratoid/rhabdoid tumors and highlights the advantages as well as the limitations of their prospective application as biomarkers and candidates for molecular therapeutic targets.

Embryonal tumors of the nervous system are the leading cause of childhood cancer-related morbidity and mortality. Medulloblastoma, supratentorial primitive neuroectodermal tumors, atypical teratoid/rhabdoid tumor and neuroblastoma account for more than 20% of childhood malignancies and typify the current neural embryonal tumor model in pediatric oncology. Mechanisms driving the formation of these tumors point towards impaired differentiation of neuronal and neuron-associated cells during the development of the nervous system as an important factor. The importance of microRNAs (miRNAs) for proper embryonic cell function has been confirmed and their aberrant expressions have been linked to tumor development. The role of miRNAs in controlling essential regulators of key pathways implicated in tumor development makes their use in diagnostics a powerful tool to be used for early detection of cancer, risk assessment and prognosis, as well as for the design of innovative therapeutic strategies. In this review we focus on the significance of miRNAs involved in the biology of embryonal neural tumors, delineate their clinical significance and discuss their potential as a novel therapeutic target.

Background: microRNA-9 is a key regulator of neuronal development aberrantly expressed in brain malignancies, including medulloblastoma. The mechanisms by which microRNA-9 contributes to medulloblastoma pathogenesis remain unclear, and factors that regulate this process have not been delineated. Methods: Expression and methylation status of microRNA-9 in medulloblastoma cell lines and primary samples were analysed. The association of microRNA-9 expression with medulloblastoma patients' clinical outcome was assessed, and the impact of microRNA-9 restoration was functionally validated in medulloblastoma cells. Results: microRNA-9 expression is repressed in a large subset of MB samples compared with normal fetal cerebellum. Low microRNA-9 expression correlates significantly with the diagnosis of unfavourable histopathological variants and with poor clinical outcome. microRNA-9 silencing occurs via cancer-specific CpG island hypermethylation. HES1 was identified as a direct target of microRNA-9 in medulloblastoma, and restoration of microRNA-9 was shown to trigger cell cycle arrest, to inhibit clonal growth and to promote medulloblastoma cell differentiation. Conclusions: microRNA-9 is a methylation-silenced tumour suppressor that could be a potential candidate predictive marker for poor prognosis of medulloblastoma. Loss of microRNA-9 may confer a proliferative advantage to tumour cells, and it could possibly contribute to disease pathogenesis. Thus, re-expression of microRNA-9 may constitute a novel epigenetic regulation strategy against medulloblastoma.

MB-108. EXPRESSION OF TROPOMYOSIN RECEPTOR KINASE C (TrkC) HAS NO MAJOR IMPACT ON THE RESPONSE TO THERAPY OF MEDULLOBLASTOMA IN VITRO AND IN A CLINICAL PATIENT COHORT Carsten Friedrich1, Tarek Shalaby2, Christoph Oehler3,4, Martin Pruschy5, Burkhardt Seifert6, Monika Warmuth-Metz7, Rolf-Dieter Kortmann8, Stefan Rutkowski9, Michael A. Grotzer2, and Andre O. von Bueren10,11; Division of Pediatric Oncology, Hematology and Hemostaseology, Department of Woman’s and Children’s Health, University Hospital Leipzig, Leipzig, Germany; Department of Oncology, University Children’s Hospital, Zurich, Switzerland; Department of Radiation Oncology, University Hospital Zurich, Zurich, Switzerland; Department of Radiation Oncology, Hospital Graubuenden, Chur, Switzerland; Laboratory for Molecular Radiobiology, Radiation Oncology, University Hospital Zurich, Zurich, Switzerland; Department of Biostatistics; Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Zurich, Switzerland; Department of Neuroradiology, University of Wuerzburg, Wuerzburg, Germany; Department of Radiation Oncology, University of Leipzig, Leipzig, Germany; Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; Department of Pediatrics, Division of Pediatric Hematology and Oncology, University Medical Center Goettingen, Goettingen, Germany; Department of Pediatrics and Adolescent Medicine, Division of Pediatric Hematology and Oncology, University Hospital of Geneva, Geneva, Switzerland BACKGROUND: High mRNA expression of the tropomyosin receptor kinase C (TrkC) has been associated with favorable survival in medulloblastoma patients. A not yet tested explanation could be that TrkC mRNA expression modulates the response to therapy. PATIENTS AND METHODS: Medulloblastoma-derived cell line DAOY, stably transfected to overexpress TrkC (clone DAOY-TrkC) and compared to a control (clone DAOY-EV, empty vector transfected), was grown under serum-free conditions (+ TrkC ligand neutrophin-3, NT-3) and cell viability was tested after irradiation or incubation with chemotherapeutic drugs after 72 h using the MTS-assay. Neuroradiologic response topostoperativechemotherapyorcraniospinal irradiation (CSI) of medulloblastoma patients aged 3-21 years with postoperative residual disease treated within the consecutive trials HIT’91/HIT2000 was compared to TrkC mRNA expression in their tumor samples. RESULTS: Cell viability of DAOY-TrkC compared to DAOY-EV was not different after incubation with increasing doses of cisplatin (0-4.8 mg/ml), etoposide (0-1.3 mg/ml), or vincristine (0-20 ng/ml), and irradiation (2, 5, 10 Gy). WhileTrkC mRNAexpression tended tobe higher in non-responders (n 1⁄4 5/19) to postoperative CSI (p 1⁄4 0.03, ratio 15.5, 95% CI 9-267), this was the case in responders (n 1⁄4 23/43) to chemotherapy (p 1⁄4 0.04, ratio 6.1, 95% CI 1.1-35, both analyzed with Mann-Withney U test and not significant after Bonferroni adjustment). CONCLUSIONS: TrkC mRNA expression was not associated with a considerable improvement in response to therapy neither in vitro nor in a MB patient cohort. The study is limited by a relatively small medulloblastoma patient cohort and the availability of only one TrkC mRNA overexpressing medulloblastoma cell line. Neuro-Oncology 18:iii97–iii122, 2016. doi:10.1093/neuonc/now076.103 #The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Medulloblastoma (MB), the most common malignant brain tumour in children, is characterised by a high risk of leptomeningeal dissemination. But little is known about the molecular mechanisms that promote cancer cell migration in MB. Aberrant expression of miR-21 is recognised to be causatively linked to metastasis in a variety of human neoplasms including brain tumours; however its function in MB is still unknown. In this study we investigated the expression level and the role of miR-21 in MB cell migration. miR-21 was found to be up-regulated, compared to normal cerebellum, in 29/29 MB primary samples and 6/6 MB-derived cell lines. Inverse correlation was observed between miR-21 expression and the metastasis suppressor PDCD4, while miR-21 repression increased the release of PDCD4 protein, suggesting negative regulation of PDCD4 by miR-21 in MB cells. Anti-miR-21 decreased protein expression of the tumour cell invasion mediators MAP4K1 and JNK, which are also known to be negatively regulated by PDCD4, and down-regulated integrin protein that is essential for MB leptomeningeal dissemination. Moreover miR-21 knockdown in MB cells increased the expression of two eminent negative modulators of cancer cell migration, E-Cadherin and TIMP2 proteins that are known to be positively regulated by PDCD4. Finally and importantly, suppression of miR-21 decreased the motility of MB cells and reduced their migration across basement membranes in vitro. Together, these compelling data propose miR-21 pathway as a novel mechanism impacting MB cell dissemination and raises the possibility that curability of selected MB may be improved by pharmaceutical strategies directed towards microRNA-21.

MicroRNAs (miRNAs) regulate a variety of cellular processes via the regulation of multiple target genes. We screened 48 medulloblastomas for mutation, deletion and amplification of nine miRNA genes that were selected on the basis of the presence of potential target sequences within the 3'-untranslated region of the MYCC mRNA. Differential PCR revealed deletions in miR-186 (15%), miR-135a-1 (33%), miR-548d-1 (42%), miR-548d-2 (21%) and miR-512-2 (33%) genes, whereas deletion or amplification was detected in miR-135b (23%) and miR-135a-2 (15%). In miR-33b, deletion, amplification or a mutation at the precursor miRNA were detected in 10% of medulloblastomas. Overall, 35/48 (73%) medulloblastomas had at least one alteration. Real-time RT-PCR revealed MYCC overexpression in 11 of 37 (30%) medulloblastomas, and there was a correlation between MYCC overexpression and miR-512-2 gene deletion (P = 0.0084). Antisense-based knockdown of miR-512-5p (mature sequence of miR-512-2) resulted in significant upregulation of MYCC expression in HeLa and A549 cells, while forced overexpression of miR-512-2 in medulloblastoma/PNET cell lines DAOY, UW-228-2, PFSK resulted in the downregulation of MYCC protein. Furthermore, the results of luciferase reporter assays suggested that miR-512-2 targets the MYCC gene. These results suggest that alterations in the miRNA genes may be an alternative mechanism leading to MYCC overexpression in medulloblastomas.

Medulloblastoma (MB) is the most common malignant brain tumor in children. It is known that overexpression and/or amplification of the MYC oncogene is associated with poor clinical outcome, but the molecular mechanisms and the MYC downstream effectors in MB remain still elusive. Besides contributing to elucidate how progression of MB takes place, most importantly, the identification of novel MYC-target genes will suggest novel candidates for targeted therapy in MB. A group of 209 MYC-responsive genes was obtained from a complementary DNA microarray analysis of a MB-derived cell line, following MYC overexpression and silencing. Among the MYC-responsive genes, we identified the members of the bone morphogenetic protein (BMP) signaling pathway, which have a crucial role during the development of the cerebellum. In particular, the gene BMP7 was identified as a direct target of MYC. A positive correlation between MYC and BMP7 expression was documented by analyzing two distinct sets of primary MB samples. Functional studies in vitro using a small-molecule inhibitor of the BMP/SMAD signaling pathway reproduced the effect of the small interfering RNA-mediated silencing of BMP7. Both approaches led to a block of proliferation in a panel of MB cells and to inhibition of SMAD phosphorylation. Altogether, our findings indicate that high MYC levels drive BMP7 overexpression, promoting cell survival in MB cells. This observation suggests the potential relevance of targeting the BMP/SMAD pathway as a novel therapeutic approach for the treatment of childhood MB.

Medulloblastoma is the most common malignant brain tumor in children and is associated with a poor outcome. We were interested in gaining further insight into the potential of targeting the human kinome as a novel approach to sensitize medulloblastoma to chemotherapeutic agents. A library of small interfering RNA (siRNA) was used to downregulate the known human protein and lipid kinases in medulloblastoma cell lines. The analysis of cell proliferation, in the presence or absence of a low dose of cisplatin after siRNA transfection, identified new protein and lipid kinases involved in medulloblastoma chemoresistance. PLK1 (polo-like kinase 1) was identified as a kinase involved in proliferation in medulloblastoma cell lines. Moreover, a set of 6 genes comprising ATR, LYK5, MPP2, PIK3CG, PIK4CA, and WNK4 were identified as contributing to both cell proliferation and resistance to cisplatin treatment in medulloblastoma cells. An analysis of the expression of the 6 target genes in primary medulloblastoma tumor samples and cell lines revealed overexpression of LYK5 and PIK3CG. The results of the siRNA screen were validated by target inhibition with specific pharmacological inhibitors. A pharmacological inhibitor of p110γ (encoded by PIK3CG) impaired cell proliferation in medulloblastoma cell lines and sensitized the cells to cisplatin treatment. Together, our data show that the p110γ phosphoinositide 3-kinase isoform is a novel target for combinatorial therapies in medulloblastoma. Mol Cancer Res; 9(7); 925–35. ©2011 AACR.

Purpose: The phosphoinositide 3-kinase (PI3K)/Akt pathway is frequently activated in human cancer and plays a crucial role in medulloblastoma biology. We were interested in gaining further insight into the potential of targeting PI3K/Akt signaling as a novel antiproliferative approach in medulloblastoma. Experimental Design: The expression pattern and functions of class IA PI3K isoforms were investigated in medulloblastoma tumour samples and cell lines. Effects on cell survival and downstream signaling were analyzed following down-regulation of p110α, p110β, or p110δ by means of RNA interference or inhibition with isoform-specific PI3K inhibitors. Results: Overexpression of the catalytic p110α isoform was detected in a panel of primary medulloblastoma samples and cell lines compared with normal brain tissue. Down-regulation of p110α expression by RNA interference impaired the growth of medulloblastoma cells, induced apoptosis, and led to decreased migratory capacity of the cells. This effect was selective, because RNA interference targeting of p110β or p110δ did not result in a comparable impairment of DAOY cell survival. Isoform-specific p110αinhibitors also impaired medulloblastoma cell proliferation and sensitized the cells to chemotherapy. Medulloblastoma cells treated with p110α inhibitors further displayed reduced activation of Akt and the ribosomal protein S6 kinase in response to stimulation with hepatocyte growth factor and insulin-like growth factor-I. Conclusions: Together, our data reveal a novel function of p110α in medulloblastoma growth and survival.

Purpose: The phosphoinositide 3-kinase (PI3K)/Akt pathway is frequently activated in human cancer and plays a crucial role in neuroblastoma biology. We were interested in gaining further insight into the potential of targeting PI3K/Akt signaling as a novel antiproliferative approach in neuroblastoma.Experimental Design: The expression pattern and functions of class IA PI3K isoforms were investigated in tumor samples and cell lines. Effects on cell survival and downstream signaling were analyzed following down-regulation of p110α or p110δ in SH-SY5Y and LA-N-1 cells by means of RNA interference.Results: Overexpression of the catalytic p110δ and regulatory p85α isoforms was detected in a panel of primary neuroblastoma samples and cell lines, compared with normal adrenal gland tissue. Although down-regulation of either p110α or p110δ led to impaired cell growth, reduced expression of p110δ also had a selective effect on the survival of SH-SY5Y cells. Decreased levels of p110δ were found to induce apoptosis and lead to lower expression levels of antiapoptotic Bcl-2 family proteins. SH-SY5Y cells with decreased p110δ levels also displayed reduced activation of ribosomal protein S6 kinase in response to stimulation with epidermal growth factor and insulin-like growth factor-I.Conclusions: Together, our data reveal a novel function of p110δ in neuroblastoma growth and survival.

BACKGROUND: Patients with incomplete surgical resection of medulloblastoma are controversially regarded as having a marker of high-risk disease, which leads to patients undergoing aggressive surgical resections, so-called second-look surgeries, and intensified chemoradiotherapy. All previous studies assessing the clinical importance of extent of resection have not accounted for molecular subgroup. We analysed the prognostic value of extent of resection in a subgroup-specific manner. METHODS: We retrospectively identified patients who had a histological diagnosis of medulloblastoma and complete data about extent of resection and survival from centres participating in the Medulloblastoma Advanced Genomics International Consortium. We collected from resections done between April, 1997, and February, 2013, at 35 international institutions. We established medulloblastoma subgroup affiliation by gene expression profiling on frozen or formalin-fixed paraffin-embedded tissues. We classified extent of resection on the basis of postoperative imaging as gross total resection (no residual tumour), near-total resection (30 Gy vs no craniospinal irradiation). The primary analysis outcome was the effect of extent of resection by molecular subgroup and the effects of other clinical variables on overall and progression-free survival. FINDINGS: We included 787 patients with medulloblastoma (86 with WNT tumours, 242 with SHH tumours, 163 with group 3 tumours, and 296 with group 4 tumours) in our multivariable Cox models of progression-free and overall survival. We found that the prognostic benefit of increased extent of resection for patients with medulloblastoma is attenuated after molecular subgroup affiliation is taken into account. We identified a progression-free survival benefit for gross total resection over sub-total resection (hazard ratio [HR] 1·45, 95% CI 1·07-1·96, p=0·16) but no overall survival benefit (HR 1·23, 0·87-1·72, p=0·24). We saw no progression-free survival or overall survival benefit for gross total resection compared with near-total resection (HR 1·05, 0·71-1·53, p=0·8158 for progression-free survival and HR 1·14, 0·75-1·72, p=0·55 for overall survival). No significant survival benefit existed for greater extent of resection for patients with WNT, SHH, or group 3 tumours (HR 1·03, 0·67-1·58, p=0·89 for sub-total resection vs gross total resection). For patients with group 4 tumours, gross total resection conferred a benefit to progression-free survival compared with sub-total resection (HR 1·97, 1·22-3·17, p=0·0056), especially for those with metastatic disease (HR 2·22, 1·00-4·93, p=0·050). However, gross total resection had no effect on overall survival compared with sub-total resection in patients with group 4 tumours (HR 1·67, 0·93-2·99, p=0·084). INTERPRETATION: The prognostic benefit of increased extent of resection for patients with medulloblastoma is attenuated after molecular subgroup affiliation is taken into account. Although maximum safe surgical resection should remain the standard of care, surgical removal of small residual portions of medulloblastoma is not recommended when the likelihood of neurological morbidity is high because there is no definitive benefit to gross total resection compared with near-total resection. FUNDING: Canadian Cancer Society Research Institute, Terry Fox Research Institute, Canadian Institutes of Health Research, National Institutes of Health, Pediatric Brain Tumor Foundation, and the Garron Family Chair in Childhood Cancer Research.

Central nervous system (CNS) cancer is a devastating illness with unmet therapeutic needs. Establishing biomarkers that have the potential to guide accurate CNS cancer diagnosis or are helpful in predicting disease progression or therapy response is of great interest. Cerebrospinal fluid (CSF) has been extensively targeted for the detection of molecules that might be useful markers for cancer detection. However, so far very few of such markers have found a standardized routine clinical application. This review examines the current scientific knowledge about the biochemical elements in the CSF that have been reported in the literature as brain cancer biomarkers and highlight reasons why the role of most markers is not yet established in the managment of CNS tumors.