MTT assay for lung cancer cell viability

According to the study of Kong et al (25), cells were cultured at a concentration of 1×10⁴ cells/well in 48-well plates. MTT solution was added to each well at a final concentration of 0.5 mg/ml and incubated for 4 h. At the end of the incubation, formazan crystals resulting from MTT reduction were dissolved by addition of 150 ml dimethyl sulfoxide (DMSO)/well. The optical density (OD) was read at 570 nm, and the average values were determined from replicate wells.