Failure of Hvaluronidase to Increase the Invasiveness of Neoplasms*

In recent papers (1, 5) it was suggested that invasion of the adjacent normal tissues by malignant tumors may be facilitated by the presence of a spreading fac,tor such as hyaluronidase. In support of this hypothesis, it was reported that some human carcinomas have been found to contain a sprcading factor. Further support would bc given to this hypothesis if it could be shown that invasiveness of neoplasms is increased by injection of hyaluronidase into or near a neoplasm, since the connective tissue barrier would presumably be weakened, and penetration of tmnor cells facilitated. Accordingly, injections of hyaluronidase were made into tumors of two kinds, a transplantable mouse sarcoma and the Shope rabbit papilloma.