Skip Navigation
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Your Environment. Your Health.

Publication Detail

Title: Killing and mutation of human lymphoblast cells by aflatoxin B1: evidence for an inducible repair response.

Authors: Kaden, D A; Call, K M; Leong, P M; Komives, E A; Thilly, W G

Published In Cancer Res, (1987 Apr 15)

Abstract: Diploid human lymphoblast cells exhibit apparent saturation of mutation induced by exposure to aflatoxin B1, despite a linear increase in the amount and proportion of the aflatoxin-DNA adducts formed. The saturation is neither a cell cycle phenomenon nor a result of a genetically heterozygous population. Examination of the biphasic nature of aflatoxin-DNA adduct loss in vivo shows initial, rapid removal of all adduct species, followed by a slow loss of the aflatoxin-N7-guanine adduct alone. We hypothesize that these data reveal two modes of adduct loss in these cells. The first is an inducible, error-free system that is short-lived, turning off as adduct levels fall below the induction threshold of some 1000 total adducts/cell. The second loss is slower and results from spontaneous depurination of remaining aflatoxin-N7-guanines. Our data are in agreement with the possibility that apurinic sites thus generated are responsible for the mutation observed. A major paradox arises from the fact that aflatoxin-related premutagenic depurinations are estimated to be only 10% of the number of spontaneous depurinations estimated by others to occur in human cells in a 1-h period.

PubMed ID: 3103909 Exiting the NIEHS site

MeSH Terms: Aflatoxin B1; Aflatoxins/metabolism; Aflatoxins/toxicity*; Cell Cycle/drug effects; Cell Line; Cell Survival/drug effects; DNA Repair/drug effects*; DNA/metabolism; Humans; Lymphocytes/drug effects*; Mutation*; Time Factors

Back
to Top