Fig. 3

Effect of DHEA on cell growth and cell cycle in normal human lung fibroblasts. A, B DHEA has anti-proliferative effects in normal human lung fibroblasts in resting media (n = 3), C without cytotoxicity at concentrations of 25–200 µM compared to control at 24, 48 and 72 h. D Cell cycle distribution of normal human lung fibroblasts is shown at 24 h and 48 h after treatment with or without 150 µM DHEA (D150). E Frequency of lung fibroblasts in G2/M phase at the beginning of the experiment (0 h) and after 24–48 h of DHEA treatment. F G6PD activity is illustrated in normal human lung fibroblasts treated with 150 µM DHEA (D150), TGF-β or both (T + D150). Bars show mean + SD. (*) p < 0.05, (**) p < 0.01, (****) p < 0.0001. DHEA: dehydroepiandrosterone; D150, DHEA 150 µM; G6PD: glucose-6-phosphate dehydrogenase (G6PD); RM: resting medium; SD: standard deviation; TGF-β1/T: transforming growth factor β1; T + D150: TGF-β1 + DHEA 150 µM