As(III) inhibits ultraviolet radiation-induced cyclobutane pyrimidine dimer repair via generation of nitric oxide in human keratinocytes

Ding, W; Hudson, LG; Sun, X; Feng, C; Liu, KJ

HERO ID

834600

Reference Type

Journal Article

Year

2008

Language

English

PMID

18621123

HERO ID 834600
In Press No
Year 2008
Title As(III) inhibits ultraviolet radiation-induced cyclobutane pyrimidine dimer repair via generation of nitric oxide in human keratinocytes
Authors Ding, W; Hudson, LG; Sun, X; Feng, C; Liu, KJ
Journal Free Radical Biology and Medicine
Volume 45
Issue 8
Page Numbers 1065-1072
Abstract Inorganic arsenic enhances skin tumor formation when combined with other carcinogens including ultraviolet radiation (UVR). The inhibition of DNA damage repair by arsenic has been hypothesized to contribute to the cocarcinogenic activities of arsenic observed in vivo. Cyclobutane pyrimidine dimers (CPDs) are an important mutagenic UVR photoproduct and implicated in the genesis of nonmelanoma skin cancer. The current study demonstrates that low concentrations of arsenite (As(III)) inhibit UVR-induced CPD repair in a human keratinocyte cell line via nitric oxide (NO) and inducible nitric oxide synthase (iNOS). Following As(III) treatment, NO production and iNOS expression are elevated. Little is known about regulation of iNOS by As(III) and further investigations indicated that p38 mitogen-activated protein kinase (p38 MAPK) and NF-kappaB are required for As(III) induction of iNOS expression. This As(III)-stimulated signaling cascade was involved in inhibition of UVR-induced CPD repair as disruption of p38 MAPK activity and NF-kappaB nuclear translocation counteracted the effects of As(III) on CPD repair. Selective inhibition of iNOS ameliorated As(III) inhibition of CPD repair, thereby suggesting that iNOS is a downstream mediator of As(III) activity. These findings provide evidence that an As(III)-stimulated signal transduction cascade culminating in elevated iNOS expression and NO generation is an underlying mechanism for inhibition of UVR-induced DNA damage repair by arsenic.
Doi 10.1016/j.freeradbiomed.2008.06.022
Pmid 18621123
Wosid WOS:000260161300003
Is Certified Translation No
Dupe Override No
Comments |WOS:000260161300003
Is Public Yes
Language Text English
Keyword Arsenite; Arsenic; Nitric oxide; iNOS; UVR
Is Qa No