Erlotinib Cytotoxicity Assessment

Transfected cells were seeded (5000 cells/well) in 96-well plates overnight and exposed to proportionally diluted erlotinib HCl (OSI-744) purchased from Selleck ranging from 1 μM to 128 μM. After 24 h incubation, 20 ml of MTT solution (5 mg/ml) was added to the medium, and the cells were incubated at 37 °C for another 4 h. Then we discarded the culture medium and added 150 ml of DMSO to each well. Absorbance (A) was measured at 570 nm using an ELISA plate reader, with background subtraction measurements done at 630 nm. The inhibition rate was calculated as described in our previous study (Hou et al. 2018b (link)): Inhibition rate = 1-[(A570-A630) of treated cells/(A570-A630) of control cells].