MMP9 and melanoma: Peinado et al. (2012) found a decrease in the secretion of various growth factors, such as placental growth factor 2 (PlGF-2) and platelet-derived growth factor A chain homodimer (PDGF-AA) after knockdown of Rab27a in melanoma cells, and Bobrie et al. (2012) observed a decrease in the release of matrix metalloproteinase 9 after knockdown of Rab27a in HeLa cells.