IIBBA   05544
INSTITUTO DE INVESTIGACIONES BIOQUIMICAS DE BUENOS AIRES
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Optimization of ROS-response promoter activity by the addition of hypoxia response motifs
Autor/es:
POLICASTRO L; IEZZI ME; WERBAJH S; CANZIANI G; PODHAJCER O
Lugar:
Buenos aires
Reunión:
Congreso; VIII Meeting of the Society for Free Radical Biology and Medicine-South American Group; 2013
Resumen:
Increased reactive oxygen species (ROS) production
appears as a distinctive feature of cancer microenvironment. Our group
developed a synthetic chimeric promoter, named E6(40)VE whose activity was
largely dependent on variations in intracellular ROS levels. Transient
expression of the thymidine kinase gene driven by E6(40)VE, followed by
gancyclovir administration, inhibited established human colorectal cancer and
melanoma cell growth in vitro and in vivo (Policastro et al, 2009, 2012).
In this work we optimized the activity of E6(40)VE by adding a hypoxic response
element (HRE). The 3 X HRE motif obtained from the VEGF promoter was placed upstream
of E6(40)VE. The 3 XHRE motif was placed 6 or 30 bp upstream of E6(40)VE to
obtain HRE(6)E6(40)VE and HRE(30)E6(40)VE, respectively. In normoxia the
HRE(6)E6(40)VE promoter exhibited only 50% of the basal activity of E6(40)VE
while HRE(30)E6(40)VE) activity was comparable to E6(40)VE. Several malignant
cell lines were transiently tranfected with HRE(30)E6(40)VE. We observed 2-3
fold increased activity in hypoxia compared to normoxia in almost all cell
lines. The highest effect was obtained in breast and pancreas cell lines. These
studies open the possibility of using this novel chimeric promoter for
therapeutic use.