GROWTH-REGULATORS IN CONNECTIVE-TISSUE - SYSTEMIC ADMINISTRATION OF AN AORTIC EXTRACT INHIBITS TUMOR-GROWTH IN MICE

Abstract

A low MW fraction prepared from extracts of bovine aorta inhibits the growth of a transplantable mammary tumor and fibrosarcoma in mice when injected systemically. It also inhibits growth of fibrosarcoma in cell culture. The effect on the fibrosarcoma is more marked than on the mammary tumor. Since the extract is more effective against the fibrosarcoma and is known to inhibit the growth of endothelial cells, it appears that the enhanced effect on this tumor is due to its activity on the endothelial cells of the host and the tumor cells themselves. The material injected is enriched in an antiproteinase previously isolated, which has anticollagenolytic activity and is presumed to be the effector molecule.