Type Culture Collection (ATCC HTB-70, Manassas, VA, USA) and were
maintained in 5% CO2 at 37 °C and cultured in Eagle’s
Minimum Essential Medium (EMEM; Cellgro) plus GlutaMAX supplemented
with 10% fetal bovine serum (FBS; Omega Scientific) and 1% penicillin/streptomycin
(Omega Scientific).
Approximately 30 000 cells were seeded
into individual wells of a 96-well tissue culture plate and incubated
for 24 h. Cells were replenished with fresh medium (0.1 mL/well; 5%
FBS, no antibiotics) and exposed to triplicates of different concentration
solutions (from 0.4 to 100 μM) of test compounds. The analyzed
inhibitors were dissolved in DMSO, reaching a final DMSO concentration
of 1%. After incubation for 24 h at 37 °C and 5% CO2, cell viability was assessed using ATPlite assay from PerkinElmer
(Waltham, MA). Viability was normalized to control cells which were
treated with the vehicle, DMSO. The reported IC50 values
were calculated by Prism5 (GraphPad).