Radiation damage to DNA in various animal tissues: A comparison of yields and repair in vivo and in vitro

The results reviewed here add weight to the idea that cultured mammalian cells irradiated in equilibrium with air may not appropriately mimic the response of cells comprising normal tissues irradiated in vivo. The major differences appear to involve at least two parameters: the degree of oxygenation and the state of differentiation. The degree of oxygenation may have more effect on the initial yield of lesions produced both in type and number, whereas the state of proliferative versus nonproliferative state may influence the repair rates. Thus, these factors could have important consequences with respect to radiation-induced cell killing, carcinogenesis, and mutation because of the envisioned role of DNA damage and repair mechanisms in these processes. 25 refs., 2 figs., 3 tabs