**4. Materials and Methods**

Firstly, we tested the Lactucin for its cytotoxicity, cell cycle inhibiting, and apoptosisinducing properties on lung adenocarcinoma cell lines. Then, its effect on cell cycle, apoptosis, and other related protein expression, was evaluated by WB analysis. Finally, we constructed a biotinylated Lactucin probe to extract Lactucin-interacting proteins, identified them using LC-MS/MS, and elucidated the molecular mechanisms.
