Figure 1.

MMP7 expression correlates with EpCAM. (a) FaDu hypopharynx carcinoma cells were transiently transfected with a control siRNA or an EpCAM-specific siRNA. Expression levels of EpCAM were assessed upon flow cytometry with specific antibodies (HO-3) in both samples. Control transfectants are represented with a solid line and EpCAM siRNA transfectants with a solid histogram. EpCAM siRNA induced a mean 43% reduction in EpCAM expression at the cell membrane. Control staining is displayed as a thin-lined graph. (b) Numbers of viable FaDu cells after transfection with control or EpCAM siRNA were determined in a standard trypan blue exclusion assay after 2 days. Shown are the mean and standard deviations of three independent experiments. Cell numbers were reduced by 35% in average after transfection of EpCAM-specific siRNA. Open graph represents mean values of FaDu cells transfected with control siRNA and solid graph EpCAM siRNA. (c) Levels of EpCAM, MMP7 and GAPDH mRNAs were determined upon RT-PCR in FaDu transfectants. Two days after transfection of control or EpCAM siRNA, cells were harvested, mRNA was isolated, and EpCAM, MMP7 and GAPDH levels were assessed with specific primer pairs. Shown are representative results from three independent experiments. H₂O served as a negative control. (d) Same as in (c) except mRNA measurement was conducted via quantitative PCR. Shown are% EpCAM (left panel) and MMP7 (right panel) mRNA expression levels from two independent experiments. P-values are indicated for each subfigure.