Pc 9 cells

NCI-N87 cells (American Type Culture Collection [ATCC], Manassas, VA, USA) and PC-9 cells (The European Collection of Authenticated Cell Cultures [ECACC], Salisbury, UK) were cultivated in RPMI-1640 (Sigma Aldrich, St. Louis, MO, USA) supplemented with 10% FBS (System Biosciences, Palo Alto, CA, USA) and 1% penicillin-streptomycin (FUJIFILM Wako, Osaka, Japan), at 37 °C under 5% CO₂.

PC-9 cells (human lung adenocarcinoma cell line) were obtained from the European Collection of Authenticated Cell Cultures (ECACC). The cells were cultured in RPMI-1640 medium containing 10% fetal bovine serum, 1% penicillin/streptomycin, and 0.1% 2-mercaptoethanol. Cultures were maintained at 37 °C and 5% CO₂, and the media were changed every three days. Cells were seeded in a 96-well plate (6 × 10⁴ cells/well) and subcultured for 24 h, and 10, 30, 100, and 300 µM isolated cordycepin and standard cordycepin were treated to each well. The cells were incubated in 5% CO₂ at 37 °C for 48 h. Subsequently, 100 µL of the solution was removed from each well, and 10 µL of CCK-8 reagent was added. After 1 h, the absorbance was measured at 450 nm using a microplate reader (Versamax, Molecular Devices, San Jose, CA, USA).