NO-donating aspirin (NO-ASA) is a promising anticancer drug. We studied the contribution of NO-ASA's components (ASA, NO-releasing moiety, and spacer linking them) to its effect. The ASA and NO-releasing moieties play no biological role: ASA inhibits the growth of colon cancer cells >100-fold less potently that NO-ASA; and denitrated NO-ASA plus the NO… (More)