C LT Receptor Blockers

LTs exert their action through two GPCR classes, BLT receptors activated by LTB4, and CysLT receptors activated by cysLTs (Brink et al., 2003). The BLT receptors are designated as BLT1 and BLT2, based on agonist affinity (Yokomizo, Izumi, & Shimizu, 2001). The receptors activated by cysLTs, CysLT1 and CysLT2, are characterized based on their sensitivity to antagonists developed for inhibition of LT-induced bronchoconstriction (Back, 2002). Inhibition of LT receptors can also attenuate the...

A LOX Inhibitors

Modulation of the various LOX isozymes may be of therapeutic value. Such approaches to chemoprevention may include inhibition of 5-LOX, FLAP, and 12-S-LOX activities or the use of LT receptor antagonists. Some of these agents are briefly discussed below. Early inhibitors of 5-LOX were nonselective antioxidants that had significant toxicity and lacked oral bioavailability (Kennedy, Chan, Ding, & Adrian, 2003). Zileuton, a specific 5-LOX inhibitor of N-hydroxyurea series (Carter et al., 1991),...

LOX Cascades

Lipoxygenases (LOXs) are a family of nonheme iron-containing dioxy-genases that are designated 5-, 8-, 12-, and 15-LOX, based on their regiospeci-ficity of interaction with arachidonic acid (Funk, 2001) (Fig. 3). LOX metabolite levels are elevated in various cancers, including colon, breast, prostate, lung, skin, and esophageal (Kashfi & Rigas, 2005). Some LOX products are procar-cinogenic, while others are anticarcinogenic (Shureiqi & Lippman, 2001). The procarcinogenic LOXs and...

Animal Models of Human Disease States

A major hurdle in the translational medicine undertaking is the fact that most preclinical animal models of disease generally lack predictive value with respect to the human condition under study. Indeed, the false positives that result from the present generation of animal assays are a major cause of NCE attrition in the clinic either because of lack of efficacy or the appearance of unacceptable side effects that were not detected preclinically. While there are notable, albeit retrospective,...

Biological Influence of the Spacer in NOASA

The defining entity in all NO-NSAIDs is NO. Structure-activity studies with NO-ASA indicated that NO was pivotal for its anticancer effects (Kashfi et al., 2005). However, careful reexamination regarding the contribution to the overall biological effect of each of the three structural components of NO-ASA in which the spacer joining the ASA to the NO-releasing moiety was aromatic, led to the surprising conclusion that the NO-releasing moiety was not required for the observed biological effects....