ABSTRACT
Em m p rin is a m em ber o f the Ig superfam ily th a t plays an essential role in several norm al tissues b u t is particularly enriched on th e surface o f m alignant tu m o r cells in vitro and in vivo. T u m o r cell em m p rin stim ulates p ro d u ctio n o f several m atrix m etalloproteinases (M M Ps) by fibroblasts and endothelial cells, b u t it also acts in an autocrine fashion to increase M M P synthesis and invasiveness in tu m o r cells them selves. In add ition , em m prin acts as a docking p ro te in for in terstitia l collagenase on the surface o f tu m o r cells. Increased expression o f em m prin in w eakly m alignant, h u m an breast cancer cells leads to dram atic augm entation o f tu m o r grow th an d invasion in vivo.
