Isolation of primary pneumocytes and lung tumor cells

Primary pneumocytes and lung tumor cells were purified as described previously (Schramek et al. 2011). For primary pneumocytes, lungs were dissected from 8-wk-old mice, infiltrated with IMDM containing 600 U/mL collagenase IV (Worthington) and 200 U/mL DNase (Worthington) through the trachea, and incubated for 1 h at 37°C; for lung tumor cells, the infiltration was performed with IMDM containing 5000 U/mL dispase (BD) and 200 U/mL DNase (Worthington) followed by same incubation condition.