Catalase Concentration

Brahn (3) observed very low liver catalase ac tivity in human beings who had died as the result of malignant growths. Later work showed that of all the individual liver enzymes studied in can cerous rats and mice the activity of catalase was by far the most affected. Greenstein and co workers (6, 7) have reported that with the pro gressive growth of the tumor there is a decrease in liver catalase activity—the activity may be as low as 1/10 to 1/20 of the original value; that the effect of the tumor growth is reversible, since on removal of the tumor the liver catalase activity returns to the original level; and that this effect is produced in general by all fast-growing tumors. Greenstein (6) and Appleman and co-workers (2) have observed that large individual variations in liver catalase occur in animals at apparently the same stage of tumor development. Both have reported that kidney and erythrocyte catalase are affected but slightly, if at all, by the presence of a tumor. The present paper reports the results obtained in a study of the effects of the growth of trans planted and spontaneous tumors on the liver cata lase concentration of mice, and the effect of the growth of mouse and rat tumor tissue cultivated in the yolk sac on the liver catalase activity of the supporting chick embryo. The yolk sac cultivation of tumor tissue in em bryonated eggs was developed in this laboratory and has been used continuously for more than 8 years (11). Tumor tissue implanted in this man ner into eggs grows vigorously and uniformly. Since nontumorous rat and mouse tissue cannot be transplanted serially in eggs, the yolk sac tumor represents a pure culture of tumor cells. It was considered that the reaction of the liver catalase concentration of chick embryos support ing the growth of rat and mouse tumor tissue could furnish data of special value in helping to resolve the problem of tumor-catalase relationship.