Fig. 2. SAHA inhibits HR repair and synergistically enhances GCV cytotoxicity in HR proficient cells.
A, HeLa-D-GFP-TK cells were incubated with SAHA alone or with the AdNGUS24i adenovirus containing the cDNA for the I-SceI endonuclease. After 48 hr, cells were assessed for GFP expression by flow cytometry. Bars represent a mean of at least three experiments performed in triplicate ± SEM. *, GFP not detectable. B, Cytotoxicity of SAHA and GCV in U251tk glioblastoma cells. C, Synergy with GCV and SAHA identified by isobologram analysis; diagonal line, isoeffective line of additivity.