The present invention discloses a method of treating cancer in a subject. This involves co-administering a replicating virus and a matrix metalloproteinase to the subject under conditions effective to treat cancer. It also relates to a method of enhancing the delivery to and distribution within a tumor mass of therapeutic viruses. This involves co-administering a replicating virus and a matrix metalloproteinase to the tumor mass under conditions effective to enhance the delivery to and distribution within the tumor mass of therapeutic viruses. Another aspect relates to a cancer therapeutic. This involves a replicating virus and a matrix metalloproteinase.
