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Low concentration of arsenite exacerbates UVR-induced DNA strand breaks by inhibiting PARP-1 activity.

ABSTRACT: Epidemiological studies have associated arsenic exposure with many types of human cancers. Arsenic has also been shown to act as a co-carcinogen even at low concentrations. However, the precise mechanism of its co-carcinogenic action is unknown. Recent studies indicate that arsenic can interfere with DNA-repair processes. Poly(ADP-ribose) polymerase (PARP)-1 is a zinc-finger DNA-repair protein, which can promptly sense DNA strand breaks and initiate DNA-repair pathways. In the present study, we tested the hypothesis that low concentrations of arsenic could inhibit PAPR-1 activity and so exacerbate levels of ultraviolet radiation (UVR)-induced DNA strand breaks. HaCat cells were treated with arsenite and/or UVR, and then DNA strand breaks were assessed by comet assay. Low concentrations of arsenite (

SUBMITTER: Qin XJ

PROVIDER: S-EPMC2584354 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature

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Low concentration of arsenite exacerbates UVR-induced DNA strand breaks by inhibiting PARP-1 activity.

Qin Xu-Jun XJ Hudson Laurie G LG Liu Wenlan W Timmins Graham S GS Liu Ke Jian KJ

Toxicology and applied pharmacology 20080710 1

Epidemiological studies have associated arsenic exposure with many types of human cancers. Arsenic has also been shown to act as a co-carcinogen even at low concentrations. However, the precise mechanism of its co-carcinogenic action is unknown. Recent studies indicate that arsenic can interfere with DNA-repair processes. Poly(ADP-ribose) polymerase (PARP)-1 is a zinc-finger DNA-repair protein, which can promptly sense DNA strand breaks and initiate DNA-repair pathways. In the present study, we ...[more]

PMID: 18619636

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