ATC Group: L01AD Nitrosoureas

Carmustine is a cell-cycle phase nonspecific antineoplastic agent of the nitrosourea type. As an alkylating agent, it can alkylate reactive sites on nucleoproteins, thus interfering with DNA and RNA synthesis and DNA repair. In addition, carmustine is known to carbamoylate lysine residues on proteins causing irreversible inactivation of enzymes including glutathione reductase.

Fotemustine is a chloroethylating nitrosourea with antineoplastic activity. Fotemustine alkylates guanine by forming chloroethyl adducts at the 6 position of guanine, resulting in N1-guanine and N3-cytosine cross linkages, inhibition of DNA synthesis, cell cycle arrest, and finally apoptosis. This agent is lipophilic and crosses the blood-brain barrier.

Lomustine’s mode of action is believed to be partly as an alkylating agent and partly by inhibition of several steps in the synthesis of nucleic acid and inhibition of the repair of single strand breaks in DNA chains.