Inhibiting the metastatic process of Breast Cancer

Breast cancer is one of the most frequent and aggressive cancers diagnosed in women in the United States. The aggressiveness of this cancer is due to its ability to metastasize to others parts of the body. More aggressive breast cancers are associated with an increase in macrophages at the site of the primary tumor. These macrophages aid in the ability of the primary tumor to metastasize by the secretion of matrix metalloproteinase (MMPs) which aid in the breakdown of the basement membrane.  Adiponectin is an anti-inflammatory protein hormone secreted by adipocyte cells. Adiponectin has been shown to inhibit the secretion of MMP2 and MMP9 in the tumor cell line MDA-MB-231. Our group has recently shown that the plant protein osmotin mimics the biological activities of adiponectin in mammalian cells via adiponectin receptors. Osmotin is a protein found commonly in tobacco plants and other sources such as fruits and vegetables. Currently I am studying the effect osmotin has on the secretion of MMPs by U937 macrophage cells, using a gelatin zymography. We hypothesize that because of the anti-inflammatory nature of adiponectin, and the similarities that osmotin has with it, that osmotin will also be an anti-inflammatory agent.  If osmotin has the ability to inhibit the secretion the MMPs this will provide a foundation for further studying the role of osmotin in the metastatic process of breast cancer.