Deletion of 11q in neuroblastomas drives sensitivity to PARP inhibition [SEQ]
ABSTRACT: SNP arrays were combined with next generation sequencing (NGS) to precisely define the deleted region in 17 primary 11q-loss neuroblastomas and identify allelic variants in genes relevant for neuroblastoma aetiology. We assessed PARP inhibitor olaparib in combination with other chemotherapy medications using both in vitro and in vivo models. Overall design: Next generation sequencing of genes relevant for neuroblastoma aetiology and cancer
Clinical cancer research : an official journal of the American Association for Cancer Research 20170822 22
Purpose: Despite advances in multimodal therapy, neuroblastomas with hemizygous deletion in chromosome 11q (20%-30%) undergo consecutive recurrences with poor outcome. We hypothesized that patients with 11q-loss may share a druggable molecular target(s) that can be exploited for a precision medicine strategy to improve treatment outcome.Experimental Design: SNP arrays were combined with next-generation sequencing (NGS) to precisely define the deleted region in 17 primary 11q-loss neuroblastomas ...[more]
Project description:SNP arrays were combined with next generation sequencing (NGS) to precisely define the deleted region in 17 primary 11q-loss neuroblastomas and identify allelic variants in genes relevant for neuroblastoma aetiology. We assessed PARP inhibitor olaparib in combination with other chemotherapy medications using both in vitro and in vivo models. Overall design: CytoScan HD arrays (Affymetrix) were performed according to the manufacturer's directions on DNA extracted from 17 neuroblastoma tumor samples and 7 neuroblastoma cell lines.
Project description:The poly-ADP-ribose polymerase (PARP) is a protein from the family of ADP-ribosyltransferases that catalyzes poly adenosine diphosphate ribose (ADPR) formation in order to attract the DNA repair machinery to DNA damage sites. Inhibition of PARP activity by olaparib can cause cell death which is of clinical relevance in some tumor types. This demonstrates that quantification of PARP activity in the context of living cells is of great importance. In this work we present the design, synthesis and biological evaluation of photo-activatable affinity probes inspired by the olaparib molecule which are equipped with a diazirine for covalent attachment upon activation by UV light and a ligation handle for the addition of a reporter group of choice. SDS-PAGE, western blotting and label-free LC-MS/MS quantification analysis show that the probes target the PARP-1 protein and are selectively outcompeted by olaparib suggesting binding in the same enzymatic pocket.
Project description:The MYCN locus is amplified in about half of high-risk neuroblastoma tumors. To identify genomic loci occupied by MYCN protein in the MYCN-amplified neuroblastoma cell lines NGP, Kelly and NB-1643, we performed chromatin immunoprecipitation coupled with Next-Generation Sequencing (ChIP-seq) using an anti-MYCN antibody. Overall design: Identification of MYCN occupancy throughout the genome of MYCN-amplified neuroblastoma cells.
Project description:Neuroblastoma is the most common extra-cranial malignancy in childhood and accounts for approximately 15% of childhood cancer deaths. Amplification of N-Myc in neuroblastoma is associated with aggressive disease and predicts for poor prognosis. Novel therapeutic approaches are therefore essential to improving patient outcomes in this setting. The histone deacetylases are known to interact with N-Myc and regulate numerous cellular processes, including differentiation in neuroblastoma. We therefore investigated the antitumor activity of the histone deacetylase inhibitor, panobinostat in the setting of N-Myc amplified neuroblastoma using the TH-MYCN murine model. Continuous treatment of tumor bearing TH-MYCN transgenic mice with panobinostat for 9 weeks led to a significant improvement in survival as compared to mice treated with vehicle, or continuous treatment with panobinostat for a three week period. Panobinostat induced rapid tumor regression with no regrowth observed during the treatment period. Tumor response was associated with an initial apoptosis phenotype mediated via up-regulation of BMF and BIM. When treated was stopped at three weeks 100% of mice relapsed with aggressive neuroblastoma. Differentiation of neuroblastoma into benign ganglioneuroma, with a characteristic increase in S100 expression and reduction of N-Myc expression, was observed in mice treated for nine weeks, resulting in a sustained remission on 90% of mice treated. RNA-sequencing analysis of tumors from treated animals confirmed significant up-regulation of gene pathways associated with apoptosis and differentiation as early as 24 hours after treatment. Together our data demonstrate the potential of panobinostat as a therapeutic strategy for high-risk neuroblastoma patients. Eight homozygous TH-MYCN mice bearing neuroblastomas were treated with either 5mg/kg panobinostat (4 animals) or vehicle (4 animals) for 24hr (two doses) and tumours harvested 4hr post the second dose.
Project description:Next-generation proteomics of Vero E6 cells infected by Italy-INMI1 SARS-CoV-2 virus for defining relevant viral peptides for detection. Cells from Day4 post-infection at 0.01 multiplicity of infection.