NCOA2 is a candidate target gene of 8q gain associated with clinically aggressive prostate cancer
GENES CHROMOSOMES & CANCER
Authors: Silva, Maria P.; Barros-Silva, Joao D.; Vieira, Joana; Lisboa, Susana; Torres, Lurdes; Correia, Cecilia; Vieira-Coimbra, Marcia; Martins, Ana T.; Jeronimo, Carmen; Henrique, Rui; Paulo, Paula; Teixeira, Manuel R.
Abstract
Prostate carcinomas harboring 8q gains are associated with poor clinical outcome, but the target genes of this genomic alteration remain to be unveiled. In this study, we aimed to identify potential 8q target genes associated with clinically aggressive prostate cancer (PCa) using fluorescence in situ hybridization (FISH), genome-wide mRNA expression, and protein expression analyses. Using FISH, we first characterized the relative copy number of 8q (assessed with MYC flanking probes) of a series of 50 radical prostatectomy specimens, with available global gene expression data and typed for E26 transformation specific (ETS) rearrangements, and then compared the gene expression profile of PCa subsets with and without 8q24 gain using Significance Analysis of Microarrays. In the subset of tumors with ERG fusion genes (ERG+), five genes were identified as significantly overexpressed (false discovery rate [FDR], 5%) in tumors with relative 8q24 gain, namely VN1R1, ZNF417, CDON, IKZF2, and NCOA2. Of these, only NCOA2 is located in 8q (8q13.3), showing a statistically higher mRNA expression in the subgroup with relative 8q gain, both in the ERG+ subgroup and in the whole series (P=0.000152 and P=0.008, respectively). Combining all the cases with NCOA2 overexpression, either at the mRNA or at the protein level, we identified a group of tumors with NCOA2 copy-number increase, independently of ETS status and relative 8q24 gain. Furthermore, for the first time, we detected a structural rearrangement involving NCOA2 in PCa. These findings warrant further studies with larger series to evaluate if NCOA2 relative copy-number gain presents prognostic value independently of the well-established poor prognosis associated with MYC relative copy-number gain. (c) 2016 Wiley Periodicals, Inc.
Helios expression coordinates the development of a subset of striatopallidal medium spiny neurons
DEVELOPMENT
Authors: Martin-Ibanez, Raquel; Pardo, Monica; Giralt, Albert; Miguez, Andres; Guardia, Ines; Marion-Poll, Lucile; Herranz, Cristina; Esgleas, Miriam; Garcia-Diaz Barriga, Gerardo; Edel, Michael J.; Vicario-Abejon, Carlos; Alberch, Jordi; Girault, Jean-Antoine; Chan, Susan; Kastner, Philippe; Canals, Josep M.
Abstract
Here, we unravel the mechanism of action of the Ikaros family zinc finger protein Helios (He) during the development of striatal medium spiny neurons (MSNs). He regulates the second wave of striatal neurogenesis involved in the generation of striatopallidal neurons, which express dopamine 2 receptor and enkephalin. To exert this effect, He is expressed in neural progenitor cells (NPCs) keeping them in the G(1)/G(0) phase of the cell cycle. Thus, a lack of He results in an increase of S-phase entry and S-phase length of NPCs, which in turn impairs striatal neurogenesis and produces an accumulation of the number of cycling NPCs in the germinal zone (GZ), which end up dying at postnatal stages. Therefore, He-/- mice show a reduction in the number of dorso-medial striatal MSNs in the adult that produces deficits in motor skills acquisition. In addition, overexpression of He in NPCs induces misexpression of DARPP-32 when transplanted in mouse striatum. These findings demonstrate that He is involved in the correct development of a subset of striatopallidal MSNs and reveal new cellular mechanisms for neuronal development.