Fig. 2: Knockdown of PDE4DIP inhibits lung cancer cell proliferation in vitro and tumorigenicity in vivo.

A shRNA-mediated knockdown of PDE4DIP expression was evaluated via Western blotting. H1299 and A549 cells were infected with lentivirus carrying either control shRNA (shNC) or a PDE4DIP-specific shRNA (shP1 or shP2) to generate PDE4DIP-KD cell lines. GAPDH was used as a control. B MTT assay in control (shNC) and PDE4DIP-KD H1299 and A549 cells. The data are representative of at least three independent experiments performed in triplicate. C Growth curves of PDE4DIP-KD H1299 and A549 cells generated via RTCA. The data were obtained from triplicate samples. D Colony formation assay in PDE4DIP-KD lung cancer cells. Left, representative images of the assay; right, data representative of at least three independent experiments performed in triplicate. Scale bar: 1.0 cm. E Growth curve of xenografts generated from control and PDE4DIP-KD NSCLC cells (n = 8). F Representative images of half of the tumours in the control and PDE4DIP shRNA-transfected groups are shown at 42 (H1299) and 25 (A549) days after cell injection. G Weights of xenograft tumours derived from control and PD4DIP shRNA-transfected NSCLC cells (n = 8 mice). ***P < 0.001. The data are presented as the means ± SD, and the P values were determined by Student’s t test. **P < 0.01; ***P < 0.001 vs. shNC.