Safe arrest

Although antimitotics remain a staple in cancer therapy for their ability to kill rapidly dividing cells, their high toxicity in normal, non-dividing cells presents a large side effect burden to patients. Diazon Pharmaceuticals Inc. is developing a compound that targets microtubules by a different mechanism than any of the approved antimitotics, resulting in a wider safety margin.

Microtubules are composed of tubulin dimers and play multiple roles in cells, including forming the mitotic spindles required for proper alignment of chromosomes during mitosis. To carry out their functions, microtubules curve and straighten repeatedly in a dynamic process that approved antimitotics inhibit in one of two ways: vinca alkaloids destabilize microtubules by enhancing their curvature and preventing them from straightening; and taxane-based agents stabilize all microtubules to block any conformational changes. In rapidly dividing cancer cells, both mechanisms induce mitotic arrest and apoptosis. ...