TY - JOUR
T1 - Enhanced CRAd activity using enhancer motifs driven by a nucleosome positioning sequence
AU - Bravo, Soraya
AU - Núñez, Felipe
AU - Cruzat, Fernando
AU - Cafferata, Eduardo G.
AU - De Ferrari, Giancarlo V.
AU - Montecino, Martín
AU - Podhajcer, Osvaldo L.
N1 - Funding Information:
This study was supported by grants from the Programa Bicentenario— BancoMundial, Conicyt, Chile CTE-06 (to O.L.P. and M.M.) and FONDAP 15090007 (to M.M.). We are indebted to the continuous support of Amigos de la Fundación Instituto Leloir para la Investigación en Cancer (AFULIC) Foundation, Argentina. F.N. was supported by a postdoctoral fellowship from CONICET and the Organización de Estados Americanos. The authors declare no conflict of interest.
PY - 2013/7
Y1 - 2013/7
N2 - Cancer development involves changes driven by the epigenetic machinery, including nucleosome positioning. Recently, the concept that adenoviral replication may be driven by tumor specific promoters (TSPs) gained support, and several conditionally replicative adenoviruses (CRAd) exhibited therapeutic efficacy in clinical trials. Here, we show for the first time that placing a nucleosome positioning sequence (NPS) upstream of a TSP combined with Wnt-responsive motifs (pART enhancer) enhanced the TSP transcriptional activity and increased the lytic activity of a CRAd. pART enhanced the transcriptional activity of the gastrointestinal cancer (GIC)-specific REG1A promoter (REG1A-pr); moreover, pART also increased the in vitro lytic activity of a CRAd whose replication was driven by REG1A-Pr. The pART enhancer effect in vitro and in vivo was strictly dependent on the presence of the NPS. Indeed, deletion of the NPS was strongly deleterious for the in vivo antitumor efficacy of the CRAd on orthotopically established pancreatic xenografts. pART also enhanced the specific activity of other heterologous promoters; moreover, the NPS was also able to enhance the responsiveness of hypoxia- and NFκB-response elements. We conclude that NPS could be useful for gene therapy approaches in cancer as well as other diseases.
AB - Cancer development involves changes driven by the epigenetic machinery, including nucleosome positioning. Recently, the concept that adenoviral replication may be driven by tumor specific promoters (TSPs) gained support, and several conditionally replicative adenoviruses (CRAd) exhibited therapeutic efficacy in clinical trials. Here, we show for the first time that placing a nucleosome positioning sequence (NPS) upstream of a TSP combined with Wnt-responsive motifs (pART enhancer) enhanced the TSP transcriptional activity and increased the lytic activity of a CRAd. pART enhanced the transcriptional activity of the gastrointestinal cancer (GIC)-specific REG1A promoter (REG1A-pr); moreover, pART also increased the in vitro lytic activity of a CRAd whose replication was driven by REG1A-Pr. The pART enhancer effect in vitro and in vivo was strictly dependent on the presence of the NPS. Indeed, deletion of the NPS was strongly deleterious for the in vivo antitumor efficacy of the CRAd on orthotopically established pancreatic xenografts. pART also enhanced the specific activity of other heterologous promoters; moreover, the NPS was also able to enhance the responsiveness of hypoxia- and NFκB-response elements. We conclude that NPS could be useful for gene therapy approaches in cancer as well as other diseases.
UR - http://www.scopus.com/inward/record.url?scp=84879687160&partnerID=8YFLogxK
U2 - 10.1038/mt.2013.93
DO - 10.1038/mt.2013.93
M3 - Article
C2 - 23712038
AN - SCOPUS:84879687160
SN - 1525-0016
VL - 21
SP - 1403
EP - 1412
JO - Molecular Therapy
JF - Molecular Therapy
IS - 7
ER -