Antitumor activity of SK-7041, a novel histone deacetylase inhibitor, in human lung and breast cancer cells.

BACKGROUND A class of synthetic histone deacetylase (HDAC) inhibitors, which are hybrids of trichostatin A and MS-275 were previously developed. In this study, the antitumor effects of SK-7041, one of those novel HDAC inhibitors, was evaluated on lung and breast cancer cell lines. MATERIALS AND METHODS Human lung and breast cancer cells, as well as normal human bronchial epithelial (NHBE) cells were treated with SK-7041, and results were compared with those of cells treated with suberoylanilide hydroxamic acid (SAHA). RESULTS SK-7041 induced time-dependent histone hyperacetylation and showed more potent cytotoxicity than SAHA in cancer cells. These antiproliferative effects of SK-7041 were due to apoptotic cell death caused by G2/M-phase arrest and to a lesser extent to G1 arrest. Moreover, SK-7041 inhibited cancer cell proliferation more selectively than NHBE cell proliferation. CONCLUSIONS These results suggest that SK-7041 may have potential anticancer activity.