Chemically Induced Hepatomas Lysosomal Hyaluronidase Activity in Normal Rat Liver and in

SUMMARY It has been demonstrated that solid hepatoma lysosomes lack hyaluronidase activity, whereas normal rat liver lyso somes contain a high level of this enzyme. This result was also found with lysosomes from an ascites hepatoma, Walker carcinoma 256, and virally transformed BHK cells. In contrast, 0-yV-acetylglucosaminidase activity was shown to be present in lysosomes from tumor cells, although its level was decreased by about 75%, compared with that of controls. As it is known that hyaluronidase and /3-/V-acetyl-glucosaminidase activities are increased in the extracellular space of tumors, we suggest that the lack of hyaluronidase and the important decrease of /8-,/V-acetylglucosaminidase in tumor lysosomes are due to a perturbation of the control of enzyme distribution from the Golgi apparatus to the lysosomes and the extracellular space.