Montrose Q: How does radiation or chemotherapy stop cancer cells from replicating?
The energy from radiation can be absorbed by DNA directly, or it can interact with cell water to create activated atoms called “free radicals.” In either case, energy is transferred to DNA resulting in chemical changes, like the formation of glued-together thymines called thymine dimers. These cannot unwind during DNA replication, so the cell dies when it tries to divide. Many cancer chemotherapy drugs cause similar damage to cancer cell DNA. More on this during our Cancer lecture.
