TY - JOUR
T1 - As(III) transcriptionally activates the gadd45a gene via the formation of H2O2
AU - Bower, Jacquelyn J.
AU - Leonard, Stephen S.
AU - Chen, Fei
AU - Shi, Xianglin
PY - 2006/7/15
Y1 - 2006/7/15
N2 - Arsenic is a ubiquitous environmental contaminant associated with increased risks of human cancers of the skin, lung, bladder, and prostate. Intriguingly, it is also used to treat certain types of leukemia. It has recently been suggested that these paradoxic effects may be mediated by arsenic's ability to simultaneously activate DNA damage and apoptotic and transformation pathways. Here, we investigate the effects of arsenic exposure on the induction of the growth arrest and DNA damage protein 45α (GADD45α), which is thought to play roles in apoptosis, DNA damage response, and cell cycle arrest. We found that arsenic transcriptionally activates the gadd45α promoter located in a 153-bp region between -234 and -81, relative to the transcriptional start site. In addition, this transcriptional induction was abrogated in the presence of H2O2 scavengers, suggesting a role for H2O2 in the transcriptional control of the gadd45a gene through a Fenton-like free radical mechanism.
AB - Arsenic is a ubiquitous environmental contaminant associated with increased risks of human cancers of the skin, lung, bladder, and prostate. Intriguingly, it is also used to treat certain types of leukemia. It has recently been suggested that these paradoxic effects may be mediated by arsenic's ability to simultaneously activate DNA damage and apoptotic and transformation pathways. Here, we investigate the effects of arsenic exposure on the induction of the growth arrest and DNA damage protein 45α (GADD45α), which is thought to play roles in apoptosis, DNA damage response, and cell cycle arrest. We found that arsenic transcriptionally activates the gadd45α promoter located in a 153-bp region between -234 and -81, relative to the transcriptional start site. In addition, this transcriptional induction was abrogated in the presence of H2O2 scavengers, suggesting a role for H2O2 in the transcriptional control of the gadd45a gene through a Fenton-like free radical mechanism.
KW - Arsenic
KW - Arsenite
KW - As(III)
KW - BEAS-2B
KW - Cell cycle control
KW - DNA damage
KW - GADD45α
UR - http://www.scopus.com/inward/record.url?scp=33745232334&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33745232334&partnerID=8YFLogxK
U2 - 10.1016/j.freeradbiomed.2006.04.007
DO - 10.1016/j.freeradbiomed.2006.04.007
M3 - Article
C2 - 16814109
AN - SCOPUS:33745232334
SN - 0891-5849
VL - 41
SP - 285
EP - 294
JO - Free Radical Biology and Medicine
JF - Free Radical Biology and Medicine
IS - 2
ER -