Invasion is the expansion of tumors into neighboring healthy tissue. MMPs act to break down the matrix structure of the healthy tissue, paving the way for the invading malignant tumor. Metastasis is the spread of tumor cells to distant locations in the body. MMPs loosen the tissue structures, permitting cancer cells to break off and spread to other locations where they can grow. In addition, the breakdown of tissues themselves trigger the release of more MMPs, which promotes further tumor growth and expansion.
Angiogenesis is the development of new blood vessels.
As a malignant tumor grows, it requires the development of blood vessels to supply its nutrients and oxygen. MMPs help these new vessels to grow by breaking down the matrix to pave the way for advancing blood vessels. During the clinical trial of the MMPI, participating patients will be randomized to receive either a pill form of the drug or placebo in combination with chemotherapy infusions. This is a multicenter, phase III study, the stage of a trial designed to determine the drug's effectiveness. Patients may experience side effects related to the MMPI including fatigue, joint stiffness, joint swelling, and, in a few patients, some limits on the mobility of certain joints, most often the shoulders and hands.