Figure 1.

Cytotoxic effect of SKI, TMZ, and the combination thereof on human glioblastoma cell lines and normal human astrocytes (NHA). Cells were treated for 72 h with the indicated amounts of SKI and TMZ. The amount of dead cells was determined by TO-PRO staining and is expressed as percent of total cells. Results shown are the mean±S.E.M. of at least three independent experiments. *P<0.05; **P<0.01; ***P<0.001 compared with the appropriate single-drug control (TMZ alone for NCH82 cells and SKI alone for all other cell lines) of the combination treatment. Arrows point to combinations of drugs that led to a potentiation effect