Figure 5. SAHA significantly reverses cisplatin resistance.

A-B: CAL27-CisR and its parental cell line CAL27 (A) or UD-SCC-2-CisR and its parental cell line UD-SCC-2 (B) were treated with different concentrations of SAHA and cell proliferation was assessed byMTT assay. C-D: CAL27-CisR (C) or UD-SCC-2-CisR (D) cells were treated with SAHA or cisplatin (CDDP) alone or in combination at 0.25, 0.5, 1, 1.5 and 2 times their respective IC₅₀ doses and cell proliferation was assessed by MTT assay. Results were analyzed according to Chou-Talalay method and the combination index (CI) values calculated by CompuSyn software. E-F: CAL27-CisR (E) or UD-SCC-2-CisR (F) cells were treated with SAHA and survivin expression was examined by Western blotting. G-H: CAL27-CisR (G) and UD-SCC-2-CisR (H) cells were treated with SAHA (3 μM and 4 μM) and tumor cell apoptosis was analyzed by annexin V staining.