Motoharu Seiki

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Gelatinase A (type-IV collagenase; M(r) 72,000) is produced by tumour stroma cells and is believed to be crucial for their invasion and metastasis, acting by degrading extracellular matrix macro-molecules such as type IV collagen. An inactive precursor of gelatinase A (pro-gelatinase A) is secreted and activated in invasive tumour tissue as a result of(More)
Matrix metalloproteinases (MMPs) are essential for proper extracellular matrix remodeling. We previously found that a membrane-anchored glycoprotein, RECK, negatively regulates MMP-9 and inhibits tumor invasion and metastasis. Here we show that RECK regulates two other MMPs, MMP-2 and MT1-MMP, known to be involved in cancer progression, that mice lacking a(More)
Migratory cells including invasive tumor cells frequently express CD44, a major receptor for hyaluronan and membrane-type 1 matrix metalloproteinase (MT1-MMP) that degrades extracellular matrix at the pericellular region. In this study, we demonstrate that MT1-MMP acts as a processing enzyme for CD44H, releasing it into the medium as a soluble 70-kD(More)
92-kDa Type IV collagenase, a member of matrix metalloproteinases, is believed to play a critical role in physiological tissue-remodeling processes and also in many pathological conditions such as tumor invasion. We analyzed the 5'-flanking sequence of the 92 kDa type IV collagenase gene that controls the expression of the gene by ligating it to the(More)
Membrane type 1 matrix metalloproteinase (MT1-MMP) is expressed on cancer cell membranes and activates the zymogen of MMP-2 (gelatinase A). We have recently isolated MT1-MMP complexed with tissue inhibitor of metalloproteinases 2 (TIMP-2) and demonstrated that MT1-MMP exhibits gelatinolytic activity by gelatin zymography (Imai, K., Ohuchi, E., Aoki, T.,(More)
Matrix metalloproteinases (MMPs) are believed to play a pivotal role in malignant behavior of cancer cells such as rapid tumor growth, invasion, and metastasis by degrading extracellular matrix (ECM). Different types of synthetic inhibitors against MMPs (MMPIs) were developed as candidates for anti-cancer therapeutics and so far clinical trials had led to(More)
Matrix metalloproteinases (MMP) degrade components of extracellular matrix (ECM), and thereby regulate formation, remodeling and maintenance of tissue. Abnormal function of cell surface proteases associated with malignant tumors may contribute directly to the invasive and malignant nature of the cells. Among the MMP's associated with the tumor cell surface,(More)
The 92-kDa type IV collagenase (matrix metalloproteinase-9; MMP-9) is frequently expressed in cells showing an invasive nature during physiological and pathological processes, and the expression is strictly controlled by a variety of trans-membrane signals. Binding sites for NF-kB, Sp-1, and AP-1 are reportedly required for induction of MMP-9 gene(More)
Cells are regulated by many different means, and there is more and more evidence emerging that changes in the microenvironment greatly affect cell function. MT1-MMP is a type I transmembrane proteinase which participates in pericellular proteolysis of extracellular matrix (ECM) macromolecules. The enzyme is cellular collagenase essential for skeletal(More)
Human retrovirus adult T-cell leukemia virus (ATLV) has been shown to be closely associated with human adult T-cell leukemia (ATL) [Yoshida, M., Miyoshi, I. & Hinuma, Y. (1982) Proc. Natl. Acad. Sci. USA 79, 2031-2035]. The provirus of ATLV integrated in DNA of leukemia T cells from a patient with ATL was molecularly cloned and the complete nucleotide(More)