Sk mes 1

Five human lung SCC cell lines, HCC‐95, HCC‐1588, SNU‐1300, SW‐900 and SK‐MES‐1, were purchased from the Korean cell line bank (Seoul, South Korea). The cell lines were cultured in RPMI‐1640 medium (Gibco, 22400‐089) supplemented with 10% fetal bovine serum (FBS, Gibco, 26140‐079), 1% penicillin‐streptomycin (Corning, 30‐002‐CI) at 37°C in 5% CO₂.
To achieve knockdown of MIF, HCC‐1588 cells were transfected with small interfering RNA (siRNA). Cells were cultured in Opti‐MEM reduced serum medium (Gibco) in accordance with the manufacturer's instructions. All siRNAs were transfected using lipofectamine 3000 reagent (Invitrogen, Carlsbad, CA, USA), according to the manufacturer's instructions. Cells were harvested 72 hours after transfection and the levels of MIF mRNA were assessed by semi‐quantitative polymerase chain reaction (PCR). Western blot analysis was used to measure MIF.

Human lung adenocarcinoma A549 and human lung squamous cell carcinoma SK-MES-1 were obtained from the Korea Cell Line Bank (Seoul, Republic of Korea). A549 was grown at 37°C in RPMI-1640 medium and supplemented with 10% FBS, penicillin (100 units/mL), and streptomycin sulfate (100 μg/mL) in a humidified atmosphere of 5% CO₂. SK-MES-1 was grown at 37°C in DMEM medium and was supplemented with 10% FBS, penicillin (100 units/mL) and streptomycin sulfate (100 μg/mL) in a humidified atmosphere of 5% CO₂. Cells were incubated with 15μM of compound K for various times (6 h, 12 h, 24 h, 36 h, or 48 h) and 48 h for various concentrations (5μM, 10μM, 15μM) in 2% FBS contained medium.