Fig. 2

Induction of cisplatin resistance by macrophage CM. (A) A549 cells were incubated with macrophage conditioned media (CM) for 8 or 24 h and then treated with 200 µM cisplatin for 24 h. (B) A549 cells were incubated with monocyte or macrophage conditioned media (CM) for 24 h and then treated with 200 µM cisplatin for 24 h. Cell viability was evaluated using a MTT assay. (C-E) A549 cells were induced with macrophage CM and treated with 200 µM cisplatin for 8 h. Cisplatin induced early apoptotic cells were identified using Annexin V and PI staining. Cisplatin induced DNA fragmentation was identified using DAPI staining. Cleavage of apoptotic proteins, PARP and caspase-3 were determined by immunoblotting. Full-length blots are presented in Supplementary Fig. [1]. Data are average values ± SD of at least three independent experiments. * p < 0.05, ** p < 0.01 (compared with 0 h and no cisplatin-treated group), ## p < 0.01 (compared with CM-induced cisplatin-treated group)