Figure 6

Mechanism of KB9520 sensitization to cisplatin cytotoxicity. A) Western blot analysis and relative densitometry of PARP1 cleavage and AKT phosphorylation in REN cells treated for 24 hours with cisplatin (25, 50 and 100 μM) or pre-treated 2 hours with KB9520 (10 nM) followed by wash-off and continued growth in normal medium ± cisplatin (25, 50 and 100 μM), for additional 24 hours. Total AKT and Tubulin staining were used for normalization. B) Effect on MET5A cell viability after 24 hours treatment with cisplatin (25, 50 and 100 μM) or 2 hours pre-treatment with KB9520 (10 nM) followed by wash-off and continued growth in normal medium ± different concentrations of cisplatin (25, 50 and 100 μM), for additional 24 hours. Each point represents mean ± s.d. *p ≤ 0.05. C) Western blot analysis and relative densitometry of PARP1 cleavage and AKT phosphorylation in MET5A cells treated with cisplatin (25, 50 and 100 μM) for 24 hours or pre-treated for 2 hours with KB9520 (10 nM) followed by wash-off and continued growth in normal medium ± different concentrations of cisplatin (25, 50 and 100 μM), for additional 24 hours. Total AKT and Tubulin staining were used for normalization. Data are representative of three separate experiments.