Lipoxin inhibits cell proliferation
(A) DNA synthesis. A549 cells were grown for 72 hr in the presence of test compounds (5–500 nM). Twenty-four hours before the assay, methyl-[3H]-thymidine (2 µCi/ml) was added to each well. Cells were subsequently washed four times with DPBS2+ (4°C), lysed with 0.25 N NaOH, and radioactivity incorporation was monitored. Values represent mean ± SEM of three different experiments performed in quadruplicate. Results are expressed as the percentage of [3H]-thymidine incorporation relative to vehicle alone. *p < 0.05 and **p < 0.005 for compounds versus vehicle. (B) Direct cell count. A549 cells were seeded in 12-well culture plates in the presence of compounds (1 µM) and cell counts were obtained at 72 hr by enumerating the trypan-blue excluding cells. Values represent mean ± SEM of three different experiments. Results are expressed as the percentage inhibition of proliferation relative to buffer. *p < 0.05 for compounds versus vehicle.