Fig. 5

Cisplatin and eugenol combination treatment inhibits the Notch signaling pathway. a Whole cell lysates were prepared from sorted spheres, and then were treated with DMSO (control), cisplatin (10 μM), eugenol (2 μM) and combination of both, and incubated for 72 h, and immunoblotting analysis was performed using antibodies against the indicated proteins. b Cells were treated with increasing concentrations of cisplatin for 24 h followed by eugenol (0.5, 1, 2, 3 and 4 μM) and DAPT (10, 20, 30, 40, 50 and 100 μM) and cell proliferation was analyzed by the WST-1 assay (n = 3, mean +/− SD; *p 0.05, **p 0.01, ***p 0.001). c Growth of spheres were determined after treatment of spheres with cisplatin (10 μM), DAPT (50 μM) and combination of cisplatin/eugenol (2 μM)/DAPT and sphere numbers were analyzed and presented as bar graphs (n = 3, mean +/− SD; * p 0.05, **p 0.01). d Cells were treated as indicated and whole cell lysates were used for immunoblotting analysis utilizing antibodies against the indicated proteins. e Cells were treated as (c) and the proportion of cells expressing cleaved caspase-3 was determined by flow cytometry