2.3.2. Cytotoxicity in Human Tumor Cell Lines

Four human tumor cell lines were used: MCF-7 (breast adenocarcinoma), NCI-H460 (non-small cell lung cancer), HeLa (cervical carcinoma) and HepG2 (hepatocellular carcinoma), as previously described by Barros et al. [23]. MCF-7, HeLa and HepG2 were obtained from the European Collection of Cell Cultures (ECACC, Salisbury, UK) and NCI-H460 was kindly provided by the National Cancer Institute (NCI, Bethesda, MD, USA). Extracts were tested at a final concentration range from 400 to 1.56 μg/mL. RPMI-1640 medium containing 10% heat-inactivated FBS and 2 mM glutamine was used to routinely maintain the adherent cell cultures at 37 ◦C, in a humidified air incubator containing 5% CO2. For the experiments, each cell line was placed at an appropriate density (1.0 <sup>×</sup> 104 cells/well) into 96-well plates. The cell growth inhibition was measured using sulforhodamine B, results were expressed as GI50 values and Ellipticine was used as a positive control.
