piperidines and sulindac-sulfone

Sulindac sulfone (exisulind), although a nonsteroidal anti-inflammatory drug derivative, induces apoptosis in tumor cells by a mechanism that does not involve cyclooxygenase inhibition. SW480 colon tumor cells contain guanosine 3',5'-monophosphate (cGMP) phosphodiesterase (PDE) isoforms of the PDE5 and PDE2 gene families that are inhibited by exisulind and new synthetic analogues. The analogues maintain rank order of potency for PDE inhibition, apoptosis induction, and growth inhibition. A novel mechanism for exisulind to induce apoptosis is studied involving sustained increases in cGMP levels and cGMP-dependent protein kinase (PKG) induction not found with selective PDE5 or most other PDE inhibitors. Accumulated beta-catenin, shown to be a substrate for PKG, is decreased by exisulind, suggesting a mechanism to explain apoptosis induction in neoplastic cells harboring adenomatous polyposis coli gene mutations.

Topics: 3',5'-Cyclic-GMP Phosphodiesterases; Antineoplastic Agents; Apoptosis; beta Catenin; Cadherins; Colonic Neoplasms; Cyclic GMP; Cyclic GMP-Dependent Protein Kinases; Cytoskeletal Proteins; Enzyme Activation; Humans; Isoenzymes; Kinetics; Phosphodiesterase Inhibitors; Piperidines; Protein Kinases; Quinazolines; Sulindac; Trans-Activators; Tumor Cells, Cultured