Histone deacetylase inhibitors (HDACIs) are emerging as a new class of antineoplastic
agents. Our purpose was to investigate the effects of the HDACIs suberoyl anilide
bishydroxamine, trichostatin A, and sodium butyrate against PNET cell lines. Treatment
with HDACIs resulted in the time- and dose-dependent accumulation of acetylated histone
proteins. Concomitantly, HDACIs provoked the dissipation of the mitochondrial membrane
potential, activation of caspase-9 and -3 and, consequently, apoptotic cell death.
In addition, HDACIs were found to interact synergistically with irradiation or apoptosis-inducing
cytokines to elicit cell death in PNET cells. These findings raise the possibility
that HDACIs may prove effective in the treatment of PNET.
This work was supported by the Wilhelm Sander-Stiftung, Neustadt/Donau and by the
Deutsche Krebshilfe.