The capacity and the lability of the coupled oxidative phosphorylation systems of liver, kidney, and of seven different tumors have been investigated with the aid of DNP and of fluoride, which act to stimulate and to inhibit, respectively, the net breakdown of high-energy phosphate. No over-all oxidative pattern common to tumor homogenates has been observed. The great difference in oxidative response among various tumors has been emphasized, and the results have been considered to represent the contribution of the tissue of origin to the enzyme pattern of the tumor tissues, and to reflect the multiplicity of enzyme patterns seen in normal growing and nongrowing tissues. The significance of the findings was discussed in relation to the problem of finding the balance between anabolic and catabolic pathways that involve the same substrates.
Part of this paper was presented before the American Association for Cancer Research, New York, 1952 (20). This investigation was supported by a research grant (C-646) from the National Cancer Institute of the Public Health Service.