Figure 4. POU5F1 knockdown in A549 LACSLCs represses MMP-2 expression and activity.
(A) qRT-PCR analysis of MMP-2 mRNA expression in A549 LACSLCs after POU5F1 knockdown. (B) POU5F1 knockdown decreases the protein expression of MMP-2 in A549 LACSLCs detected by western blot analysis. (C) ChIP analysis of transcript factor POU5F1 binding to MMP-2 promoter. (D) Luciferase reporter assay demonstrates inactivation of the MMP-2 promoter after POU5F1 knockdown in A549 LACSLCs. Cells were transiently transfected with a luciferase reporter construct using Lipofectamine 2000 reagent. After incubation for 24h, cells were harvested in passive lysis buffer, and the luciferase activities were measured by a luminometer using the luciferase assay system. All experiments were performed at least in triplicates and data are presented as the mean ± SEM. Student t test was performed to evaluate the difference.