Matrix metalloproteinase 9 (92-kDa gelatinase/type IV collagenase) from HT 1080 human fibrosarcoma cells. Purification and activation of the precursor and enzymic properties - Okada, Y; Gonoji, Y; Naka, K; Tomita, K; Nakanishi, I; Iwata, K; Yamashita, K; Hayakawa, T (J Biol Chem, 1992)