Surgery Which of the following is the main mechanism by which the mechlorethamine exes its cell killing? A Alkylating DNA, causing cross-links between parallel DNA strands B Blocking microtubular assembly and mitosis during M-phase C Inhibiting topoisomerase, preventing repair of DNA strand breaks D Intercalating in DNA strands, there by preventing DNA replication by Mrna 💡 Explanation Which of the following is the main mechanism by which the mechlorethamine exes its cell killing? ✓ Correct Answer: A. Alkylating DNA, causing cross-links between parallel DNA strands