ABSTRACT
Mutagens in the environment, tobacco, food, as well as endogenous metabolic products generate highly reactive electrophilic species that alkylate cellular DNA. Among those agents are food-specifi c N-nitrosamines, such as N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine (NDEA), N-nitrosopyrrolidine (NPYR) and N-nitrosopiperidine (NPIP), and the tobacco-specific nitrosamines 4-(methylnitrosamino)-1-(3-pyridyl)-1butanone (NNK) and N-nitrosonornicotine (NNN). In addition, alkylating agents are used in cancer chemotherapy due to their high cytotoxic properties (see Chapter 5). Examples of alkylating anticancer drugs are the methylating agents procarbazine, dacarbazine, streptozotocin and temozolomide(TMZ) and the chloroethylating agents carmustine (BCNU), lomustine (CCNU), nimustine (ACNU) and fotemustine.
