MMP9 and carcinoma: Some recent studies suggest that tissue inhibitor of metalloproteinases-1 (TIMP-1) and gelatinase B (MMP-9) could be utilized as novel tumor markers in the determination of prognosis in the carcinomas of head and neck, breast, ovary, and colon (Holten-Andersen et al. 2000; Ranuncolo et al. 2003; Talvensaari-Mattila et al. 2005a; Talvensaari-Mattila et al. 2005b; Rauvala et al. 2005; Ruokolainen et al. 2005a; Ruokolainen et al. 2005b).