Silencing of TGIF attenuates the tumorigenicity of A549 cells in vitro and in vivo

The aim of this study was to investigate the effects of the silencing of the TG-interacting factor (TGIF) on the tumorigenicity of A549 cells in vitro and in vivo. Stable TGIF-silenced A549 cells were established by infecting shRNA lentiviral particles. Western blotting analysis was used to detect the expression of proteins. Cell cycle was detected by flow cytometry. Soft agar assay and tumor formation assay in nude mice were applied. The silencing of TGIF inhibited A549 cell proliferation, colony formation in vitro, growth of tumor xenograft in vivo, and arrested the cell cycle in the G1 phase. The expression of CDK4, cyclin D1, and phospho-Rb was markedly decreased in the A549-shTGIF cells compared with the A549-shcon cells, and p21 was markedly increased in the A549-shTGIF cells compared with the A549-shcon cells. A lower level of β-Catenin protein expression was observed in the A549-shTGIF cells than that in the A549-shcon cells. The silencing of TGIF attenuates the tumorigenicity of A549 cells in vitro and in vivo.