MMP2 and malignant colon neoplasm: Additional studies in colon cancer have demonstrated the ability of SphK1 to also induce the expression of matrix metalloproteinases 2/9 [57,76], and given the correlation between SphK1 activity and COX-2 expression, it seems that SphK1 and COX-2 converge on matrix metalloproteinases to promote colon cancer growth and progression.