0000000000709846
AUTHOR
Niloufar Javanmardi
Abstract 495: Amplification of chromosomal regions 12q13-14 and 12q15 defines a distinct subgroup of high-risk neuroblastoma patients and is associated with atypical clinical features
Abstract Neuroblastoma is a pediatric cancer of the sympathetic nervous system with wide heterogeneity regarding clinobiological subtypes, ranging from patients with tumors of spontaneous regression to patients with aggressive tumors with fatal outcome despite multimodal treatment. MYCN-amplification and 11q-deletion are important, although incomplete, markers of high-risk neuroblastoma. Thus, characterization of additional genomic alterations that can be used as prognostic and/or predictive markers is of clinical importance in order to provide best possible treatment. From genomic profiles generated through high-density SNP microarrays we identified a group of neuroblastomas (14 primary tu…
11q Deletion or ALK Activity Curbs DLG2 Expression to Maintain an Undifferentiated State in Neuroblastoma
High-risk 11q deleted neuroblastomas typically display undifferentiated/poorly differentiated morphology. Neuroblastoma is thought to develop from Schwann cell precursors and undifferentiated neural crest (NC) derived cells. It is therefore vital to understand mechanisms involved in the block of differentiation. We identify an important role for oncogenic ALK-ERK1/2-SP1 signaling in maintenance of undifferentiated NC-derived progenitors via repression of DLG2, a tumor suppressor in neuroblastoma. DLG2 is expressed in the ‘bridge signature’ that represents the transcriptional transition state when neural crest cells or Schwann Cell Precursors become chromaffin cells of the adrenal gland. We …
Abstract 2435: Amplification of CDK4 and MDM2 is associated with atypical clinical features in high risk neuroblastoma patients
Abstract MYCN-amplification and 11q-deletion are important, although incomplete, markers of high-risk neuroblastoma. Thus, characterization of additional genomic alterations that can be used as prognostic and/or predictive markers is of clinical importance in order to provide best treatment possible. By using SNP-microarrays we identified a small group of neuroblastomas with high grade amplification of one or multiple loci on 12q, commonly involving the potential oncogenic target genes CKD4 (12q13-14) and/or MDM2 (12q15). The CDK4 and MDM2 regions were co-amplified in 13/16 samples, two tumors had CDK4-amplification in absence of MDM2-amplification while one tumor had MDM2-amplification wit…
Abstract 4107: Targeted re-sequencing of neuroblastoma tumors reveals chromosomal rearrangements that involve the Anaplastic Lymphoma Kinase (ALK) gene.
Abstract Neuroblastoma (NBL) is a cancer of early childhood arising from the developing sympathetic nervous system. NBL tumors display a broad clinical and biological heterogeneity, ranging from highly aggressive tumors with fatal outcome to tumors with spontaneous regression. Recurrent mutations are mainly only observed in Anaplastic Lymphoma Kinase (ALK), which is involved in the pathogenesis of both familiar and sporadic NBL. ALK encodes a tyrosine kinase receptor with importance in neuronal development and was initially characterized in anaplastic large cell lymphoma from a translocation leading to the NPM-ALK fusion protein. Subsequent studies show that additional ALK chimeras have bee…
Intragenic anaplastic lymphoma kinase (ALK) rearrangements: Translocations as a novel mechanism ofALKactivation in neuroblastoma tumors
Anaplastic lymphoma kinase (ALK) has been demonstrated to be deregulated in sporadic as well as in familiar cases of neuroblastoma (NB). Whereas ALK-fusion proteins are common in lymphoma and lung cancer, there are few reports of ALK rearrangements in NB indicating that ALK mainly exerts its oncogenic capacity via activating mutations and/or overexpression in this tumor type. In this study, 332 NB tumors and 13 cell lines were screened by high resolution single nucleotide polymorphism microarray. Gain of 2p was detected in 23% (60/332) of primary tumors and 46% (6/13) of cell lines, while breakpoints at the ALK locus were detected in four primary tumors and two cell lines. These were furthe…