These were carried out following the
reported protocol.20−22 Hence, MDB-MB-231, human breast cancer
cells, were cultured in Dulbecco’s modified Eagle medium (DMEM),
supplemented with 10% (v/v) fetal bovine serum, 2 mM L-glutamine,
100 units/mL penicillin, and 100 μg/mL streptomycin at 37 °C in
humidified 5% CO2. For cytotoxicity assays, cells were seeded in 96-
well plates at optimal cell density (10 000 cells per well) to ensure
exponential growth for the duration of the assay. After a 24 h
preincubation growth, the medium was replaced with experimental
medium containing the appropriate drug concentrations or vehicle
controls (0.1% or 1.0% v/v DMSO). After 72 h incubation, cell
viability was measured using Alamar Blue reagent (Invitrogen Ab,
Lidingö, Sweden) according to the manufacturer’s instructions.
Absorbance was measured at 570 nm with 600 nm as a reference
wavelength. Results were expressed as the mean ± standard error for
six replicates as a percentage of vehicle control (taken as 100%).
Experiments were performed independently at least six times.
Statistical analyses were performed using a two-tailed Student’s t
test. P < 0.05 was considered to be statistically significant.