Figure 1.

Radiation-resistant cells exhibit elevated glucose metabolism. (A) Selection of radiation-resistant cells from the A549 parental cells. A549 radioresistant cells were pooled and cell viabilities were analyzed by treatment with radiation at 0, 0.5, 1, 2, 4 and 6 Gy. (B) Cell death and morphological changes in the A549 radiosensitive and -resistant cells in response to radiation treatments at 0, 1 and 4 Gy. (C) Glucose uptake (left) and lactate production (right) were measured in the A549 radiosensitive and radioresistant cells. Columns represent the mean of three independent experiments; bars represent the standard error. *P<0.05 and **P<0.01 vs. IR sensitive cells. IR, irradiation; -, no radiation; +, radiation at 1 Gy; ++, radiation at 4 Gy.