In:
Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 114, No. 16 ( 2017-04-18), p. 4207-4212
Abstract:
Global distribution of hepatocellular carcinomas (HCCs) is dominated by its incidence in developing countries, accounting for 〉 700,000 estimated deaths per year, with dietary exposures to aflatoxin (AFB 1 ) and subsequent DNA adduct formation being a significant driver. Genetic variants that increase individual susceptibility to AFB 1 -induced HCCs are poorly understood. Herein, it is shown that the DNA base excision repair (BER) enzyme, DNA glycosylase NEIL1, efficiently recognizes and excises the highly mutagenic imidazole ring-opened AFB 1 -deoxyguanosine adduct (AFB 1 -Fapy-dG). Consistent with this in vitro result, newborn mice injected with AFB 1 show significant increases in the levels of AFB 1 -Fapy-dG in Neil1 −/− vs. wild-type liver DNA. Further, Neil1 −/− mice are highly susceptible to AFB 1 -induced HCCs relative to WT controls, with both the frequency and average size of hepatocellular carcinomas being elevated in Neil1 −/− . The magnitude of this effect in Neil1 −/− mice is greater than that previously measured in Xeroderma pigmentosum complementation group A (XPA) mice that are deficient in nucleotide excision repair (NER). Given that several human polymorphic variants of NEIL1 are catalytically inactive for their DNA glycosylase activity, these deficiencies may increase susceptibility to AFB 1 -associated HCCs.
Type of Medium:
Online Resource
ISSN:
0027-8424
,
1091-6490
DOI:
10.1073/pnas.1620932114
Language:
English
Publisher:
Proceedings of the National Academy of Sciences
Publication Date:
2017
detail.hit.zdb_id:
209104-5
detail.hit.zdb_id:
1461794-8
SSG:
11
SSG:
12
