The
matrix metalloproteinases (
MMPs), belonging to the family of
proteolytic enzymes, are well-known for their ability to degrade the extracellular matrix, and are involved in many aspects of both physiological cellular processes and pathological situations, such as
tumor growth, invasion and
metastasis.
MMPs have been considered prognostic factors in various types of
cancer as well as promising targets for
cancer therapy. Although preclinical studies of a number of different synthetic
MMP inhibitors have been identified as
cytostatic and anti-angiogenic agents and have begun clinical testing, the past years have produced a consistent number of disappointments and limited successes. In view of their specific implication in malignant tissues, several natural compounds were utilized, and the results were so satisfactory as to encourage several clinical trials in order to improve efficacy and to reduce the side effect profile. The natural protection against
cancer has been receiving a great deal of attention, and the critical examination of previous studies shed light on new information about the source and function of
MMPs, focusing the attention on the identification of
MMP targets in
tumors. This review discusses the current knowledge and research in the field of natural
MMP inhibitor as innovative therapeutic intervention in
cancer.