INHIBITION OF MOTILITY AND INVASION OF B16 MELANOMA BY THE OVEREXPRESSION OF CYSTATIN-C

Although increased expression of cysteine proteinases has been shown t o be correlated with increased metastasis for a wide variety of tumour s, the contribution of cysteine proteinases to the metastatic spread o f tumour cells is not well understood. In order to examine this questi on we have overexpressed a specific cysteine proteinase inhibitor, cys tatin C, by stable transfection of B16F10 melanoma. Increased expressi on of cystatin C inhibited motility and in vitro invasiveness of B16 m elanoma by 50% in both stimulated (autocrine motility factor, laminin) and unstimulated cells. These results suggest that cysteine proteinas es are involved in B16 melanoma motility and invasion.