Figure 1. Trop2-knockdown results in proliferation inhibition and G₂-phase accumulation in lung cancer cells. (A) Western blot analysis showing the Trop-2 protein level of A549 (left) and PC14 cells (right), stably transfected with either shNC or shTrop-2 and their corresponding parental cells. β-actin levels served as loading control. (B) Cell proliferation of A549 and PC14 lung cancer cells stably transfected with shTrop2 or nontarget control shRNA was detected by MTT assay. The viability of shNC transfected cells was considered as 100%. Data represented the mean ± SD of three independent experiments. (C) A549 and PC14 lung cancer cells were stably transfected with shTrop2 or nontarget control shRNA, cell cycle distribution was assessed by means of flow cytometry. The distribution of cells in the G₁, S, and G₂/M phases of the cell cycle were calculated and labeled.