Belinostat is a novel HDAC inhibitor with IC50 of 27 nM, with activity demonstrated in cisplatin-resistant tumors.
Belinostat inhibits the growth of tumor cells (A2780, HCT116, HT29, WIL, CALU-3, MCF7, PC3 and HS852) with IC50 from 0.2-0.66 μM. PD101 shows low activity in A2780/cp70 and 2780AD cells, which are cisplatin and doxorubicin-resistant derivatives of A2780 cells. Belinostat could induce apoptosis through PARP cleavage and acetylation of histones H3/H4. Belinostat inhibits bladder cancer cell growth, especially in 5637 cells, which shows accumulation of G0-G1 phase, decrease in S phase and increase in G2-M phase.The growth inhibitory activity of belinostat on cell lines is not strongly influenced by the multidrug-resistant phenotype, whereas the activity of docetaxel is clearly affected. Belinostat could enhance the growth inhibitory activity of docetaxel or carboplatin in OVCAR-3 and A2780 cells. Belinostat also shows enhanced tubulin acetylation in ovarian cancer cell lines. A recent study shows that Belinostat activates protein kinase A in a TGF-β signaling-dependent mechanism and decreases survivin mRNA. |