Is Oxygen a Radiation Sensitizer?

Oxygen is a potent radiosensitizer, increasing the effectiveness of a given dose of radiation by forming DNA-damaging free radicals. Tumor cells in a hypoxic environment may be as much as 2 to 3 times more resistant to radiation damage than those in a normal oxygen environment.

What is a radiation sensitizer?

The term radiation sensitizer is used to describe agents that selectively enhance the cell killing from irradiation in tumor cells while exhibiting no single agent toxicity on tumor or normal tissues.

What role does oxygen play in radiation therapy?

Supplying Oxygen to Boost Radiation Therapy

Much of this resistance is caused by the low levels of oxygen often found in tumors: oxygen is required for radiation therapy to generate the molecules, called free radicals, that kill cancer cells.