MMP9 and cancer: Similarly, the protein levels of the EMT markers such as fibronectin, vimentin, MMP9, slug and zeb1 were increased remarkably in HeyA8‐Rap1A cDNA cells while interruption of Rap1A downregulated fibronectin, vimentin, MMP9, slug and zeb1, indicating that Rap1A may promote cancer cell migration and invasion through EMT (Fig. 5A).