*4.1. Cell Materials*

In the present study, we observed the effect of Lactucin (Shanghai Yuanye Biological Technology Co., Ltd., Shanghai, China) on two lung adenocarcinoma cell lines, namely, A549 (Cell Bank of Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China), and H2347 (Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China), as well as one normal lung cell line MRC-5 (National Infrastructure of Cell Line Resource, Beijing, China).
