Abstract: This invention provides methods of treating a subject suffering from a leiomyoma which comprise administering to the subject a therapeutically effective amount of an agent, or alternatively a plurality of agents, which inhibit specific metalloproteinases. This invention further provides diagnostic methods of determining whether a tumor in a subject is a leiomyoma. This invention further provides pharmaceutical compositions and kits for practicing the instant methods. Finally, this invention provides a method of determining whether an agent specifically inhibits certain metalloproteinases.