MMP2 and MMP9 participate in S1P-induced invasion of follicular ML-1 thyroid cancer cells.

The bioactive lipid sphingosine-1-phosphate (S1P) has emerged as a potent inducer of cancer cell migration and invasion. Previously, we have shown that S1P induces invasion of ML-1 follicular thyroid cancer cells via S1P receptors 1 and 3 (S1P1,3). Matrix metalloproteinases (MMPs) are zinc-dependent proteolytic enzymes used by cells for degradation of the extracellular matrix during invasion and migration. In the present study, we examined the role of MMP2 and MMP9 for S1P-induced invasion of ML-1 cells, and found that S1P regulates the secretion and activity of MMP2 and MMP9 via S1P1,3. Both pharmacological inhibitors and siRNA knockdown of MMP2 and MMP9 could attenuate S1P-induced invasion. Additionally, we show that calpains and Rac1 mediate S1P-induced secretion of MMP2 and MMP9. In conclusion, MMP2 and MMP9 participate in S1P-evoked follicular ML-1 thyroid cancer cell invasion.