In an in vitro co-culture model, omental adipose-derived MSCs were found to significantly stimulate the proliferation and invasion of ovarian cancer cells by elevating matrix metalloproteinases (MMPs), which is a family of zinc-dependent endopeptidases, particularly MMP-2 and MMP-9, whereas the inhibition of MMP-2 and MMP-9 was found to partially reduce the tumor-promoting effects of these MSCs. This evidence concerns the gene MMP9 and neoplasm.