Please use this identifier to cite or link to this item: https://scholarbank.nus.edu.sg/handle/10635/111758
Title: A method for simultaneous identification of human active and active-site alkylated O6-methylguanine-DNA methyltransferase and its possible application for monitoring human exposure to alkylating carcinogens
Authors: Ayi, T.-C. 
Oh, H.-K.
Lee, T.K.-Y.
Li, B.F.L. 
Issue Date: 15-Jul-1994
Citation: Ayi, T.-C.,Oh, H.-K.,Lee, T.K.-Y.,Li, B.F.L. (1994-07-15). A method for simultaneous identification of human active and active-site alkylated O6-methylguanine-DNA methyltransferase and its possible application for monitoring human exposure to alkylating carcinogens. Cancer Research 54 (14) : 3726-3731. ScholarBank@NUS Repository.
Abstract: Cells resist the major mutagenic effects of alkylating agents by the action of O6-methylguanine-DNA methyltransferase (MGMT), which transfers the alkyl (R) group of O6-alkylguanine, produced in DNA by these chemicals, to a cysteine residue in its active site (formation of R-MGMT). We demonstrate that cellular R-MGMT (which represents a record or memory within the cells exposed to these chemicals) can be assayed by its sensitivity toward proteolysis by protease V8. The possible use of this assay for monitoring exposure to alkylating carcinogens was investigated by using cultured cells and a preliminary study with the use of human blood from normal subjects and patients undergoing chemotherapy. Cultured cell experiments show that R-MGMT is sufficiently stable for the monitoring purpose and its level bears a dose-response relationship to the concentrations of the alkylating agent used. Interestingly, experiments with blood from patients undergoing chemotherapy show a gradual formation of R-MGMT in 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea and an induced MGMT deficiency in cyclophosphamide-treated patients. The use of this methodology, which allows for the possible quantification of active MGMT (cellular DNA repair capacity) and R-MGMT (recent exposure) simultaneously, in monitoring human exposure to alkylating carcinogens is discussed.
Source Title: Cancer Research
URI: http://scholarbank.nus.edu.sg/handle/10635/111758
ISSN: 00085472
Appears in Collections:Staff Publications

Show full item record
Files in This Item:
There are no files associated with this item.

Page view(s)

59
checked on Jul 19, 2019

Google ScholarTM

Check


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.