MMP9 and liposarcoma: IL-1β stimulated MMP-9 and MMP-2 in chondrosarcoma cells, enhanced levels of both MMPs at 1 ng/ml but decreased levels at 25 ng/ml in fibrosarcoma, inhibited MMP-2 and enhanced MMP-9 at 1 and 10 ng/ml and downregulated at 25 ng/ml in liposarcoma cells.