The strong induction of MMP-9 in the co-culture can be explained by the enhanced secretion of TNFα (Figure 2C), which is a very strong inducer of MMP-9 [50], and the relative mild response to soluble EMMPRIN at high doses demonstrates the ability of EMMPRIN to induce MMP-9 secretion from tumor cells even in the absence of TNFα. Here, TNF is linked to neoplasm.