Suppression of PGE2 in plasma and nevi following 1 week of daily ASA exposure. Human subjects were each given ASA daily for one week, and blood and nevus samples were obtained both before (pre) and after (post) this period. (A), Protocol for 325 mg dosing. (B), Levels of PGE2 in plasma and nevi in the 325 mg cohort. Error bars represent SEM. * p < 0.0001, ** p = 0.004, paired t-tests. (C), Average percent reduction in PGE2 levels from (B). Error bars represent SEM. (D), Protocol for 81 mg dosing. (E), Levels of PGE2 in plasma and nevi in the 81 mg cohort. * p < 0.0001, paired t-tests. (F), Average percent reduction in PGE2 levels from (E). Error bars represent SEM.