4.2. Biochemistry
4.2.1. Cell culture and drug treatment
C6 Rat glioma, NIH/3T3 mouse embryonic fibroblast and 5RP7 H-ras oncogene transformed rat embryonic fibroblast cells were incubated in Dulbecco's Modified Eagle's Medium (DMEM) (Sigma, Deisenhofen, Germany) supplemented with 10% fetal calf serum (Gibco, Paisley, Scotland). A549 Human lung adenocarcinoma cells were incubated in 90% RPMI supplemented with 10% fetal bovine serum (Gibco, Paisley, Scotland). All media were supplemented with 100 IU/mL penicillin-streptomycin (Gibco, Paisley, Scotland) and cells were incubated at 37 C in a humidified atmosphere of
95% air and 5% CO2. Exponentially growing cells were plated at 2 104 cells/mL into 96-well microtiter tissue culture plates (Nunc,Denmark) and incubated for 24 h before the addition of the drugs(the optimum cell number for cytotoxicity assays was determined in preliminary experiments). The stock solutions of the compounds were prepared in dimethyl sulfoxide (DMSO; Sigma Aldrich, Poole, UK) and further dilutions were made with fresh culture medium (the concentration of DMSO in the final culture medium was