TIMP1 and neoplasm: To test this hypothesis, the aims of the present report were (i) to determine whether CDV infection of tumor cells can be maintained during in vivo treatment of established tumors and (ii) to investigate the impact of a CDV infection on tumor progression through direct oncolytic effects or modulation of the tumor microenvironment with special emphasis on tumor-associated macrophages, expression of selected MMPs and TIMP-1, and angiogenesis.