BM-40 and MMP-2 expression are not coregulated in human melanoma cell lines

As published recently, suppression of BM-40 (osteonectin, SPARC) expression reduced the in vitro adhesive and invasive capacities of melanoma cells. In parallel, a decreased production of matrix metalloproteinase-2 (MMP-2) was observed in these cells indicating a close coregulation of these two proteins. However, analysis of 12 independently established melanoma cell lines, exhibiting different metastatic capacities, did not reveal a positive correlation between BM-40 or MMP-2 expression and the metastatic capacities of these cell lines. In addition, direct comparison of BM-40 and MMP-2 mRNA levels did not provide evidence for coregulation of these two proteins. This was further corroborated by the finding that exogenous BM-40 failed to alter synthesis and activation of proMMP-2.