About “Qing-Xiang Amy Sang”

Professor Sang and her students, postdoctoral fellows, and collaborators have discovered and characterized a novel matrix metalloproteinase (endometase/matrilysin-2/MMP-26) in human cancers of endometrium, breast, and prostate. This protein is a putative cancer biomarker for human prostate, breast, and other types of carcinomas. The Sang lab is also investigating other new cancer biomarkers including phosphoproteins and glycoproteins. Furthermore, Dr. Sang lab has cloned human disintegrin and metalloproteinase 19 (adamalysin 19 or ADAM 19) gene and characterized its protein. Sang lab uncovered that matrilysin and gelatinase B have plasminogen-angiostatin converting enzyme activities. This type of biochemical research may contribute to an understanding of fundamental proteinase biochemistry and cell biology. The new knowledge may have potential applications to help patients with cancer, stroke, arthritis, diabetes, obesity, and cardiovascular diseases.

Dr. Sang’s laboratory is interested in protein chemistry and enzymology of metalloproteinases and their natural and synthetic inhibitors. The biological and pathological roles of these enzymes and inhibitors are investigated in the regulation of adult mesenchymal stem cell differentiation and fate. The classical biochemistry is combined with molecular biology, cell biology, material science, medicinal chemistry, and biomedical sciences. New metalloproteinases such as human tumor-derived endometase/matrilysin-2 (matrix metalloproteinase–26) and protease inhibitors such as tissue inhibitor of metalloproteinase-4 are under investigation, including cDNA cloning, protein expression, isolation, purification, characterization, sequencing, and chemical modifications. The research team is focusing on the studies of the biochemical mechanisms of zymogen activation, substrate specificities, the inhibition kinetics, and the structure-function relationships of the proteinases and their inhibitors. These synthetic small molecular enzyme inhibitors may be further developed to become potential candidates for therapeutics for treating cancer invasion, metastasis, stroke, and obesity.

Sang research team is exploring the biochemical basis and molecular mechanisms of human cancer cell progression, invasion, and metastasis. Matrix metalloproteinases (MMPs or matrixins) are a family of endopeptidases that require zinc for catalysis and calcium for protein folding. Because of their abilities to dissolve connective tissue barrier proteins such as collagens, fibronectin, and laminins, matrixins are one of the most important classes of molecules used by invading cells to facilitate invasive growth and spread. Angiogenesis, the process of new blood vessel formation, is essential for providing oxygen and nutrients for tumor growth and for generating a gateway for cancer cell metastasis. Inhibition of angiogenesis will starve tumors, induce cancer regression, and prevent the spread of cancer cells. Dr. Sang and her associates and collaborators are performing experiments to gain an understanding of the biochemical steps involved in metastasis and to develop new strategies to prevent tumor growth and to inhibit cancer angiogenesis and metastasis. Inhibition of angiogenesis may also starve fat cells and restrict fat tissue growth, thus, preventing and reducing obesity.