Referenced in: none

Automatically associated channels: TRP , TRPM , TRPM3

Title: High-resolution genomic analysis does not qualify atypical plexus papilloma as a separate entity among choroid plexus tumors.

Authors: Anna Sophia Japp, Marco Gessi, Martina Messing-Jünger, Dorota Denkhaus, Anja Zur Mühlen, Johannes Ernst Wolff, Stefan Hartung, Uwe Kordes, Ludger Klein-Hitpass, Torsten Pietsch

Journal, date & volume: J. Neuropathol. Exp. Neurol., 2015 Feb , 74, 110-20

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/25575132

Abstract
Choroid plexus tumors are rare neoplasms that mainly affect children. They include papillomas, atypical papillomas, and carcinomas. Detailed genetic studies are rare, and information about their molecular pathogenesis is limited. Molecular inversion probe analysis is a hybridization-based method that represents a reliable tool for the analysis of highly fragmented formalin-fixed paraffin-embedded tissue-derived DNA. Here, analysis of 62 cases showed frequent hyperdiploidy in papillomas and atypical papillomas that appeared very similar in their cytogenetic profiles. In contrast, carcinomas showed mainly losses of chromosomes. Besides recurrent focal chromosomal gains common to all choroid plexus tumors, including chromosome 14q21-q22 (harboring OTX2), chromosome 7q22 (LAMB1), and chromosome 9q21.12 (TRPM3), Genomic Identification of Significant Targets in Cancer analysis uncovered focal alterations specific for papillomas and atypical papillomas (e.g. 7p21.3 [ARL4A]) and for carcinomas (16p13.3 [RBFOX1] and 6p21 [POLH, GTPBP2, RSPH9, and VEGFA]). Additional RNA expression profiling and gene set enrichment analysis revealed greater expression of cell cycle-related genes in atypical papillomas in comparison with that in papillomas. These findings suggest that atypical papillomas represent an immature variant of papillomas characterized by increased proliferative activity, whereas carcinomas seem to represent a genetically distinct tumor group.