Effects Of High Dose Ascorbate On Tumor Growth In Guinea Pigs
Recent studies indicate that a host's susceptibility to cancer is determined to a large extent by the natural resistance of the host to the disease (1). Consequently, there has developed a wave of interest concerning the theory that measures designed to enhance host resistance will result in an inhibition of malignant invasive growth. One important factor in host resistance is the availability of ascorbic acid (2-4). It has been shown that ascorbate can be used to inhibit in-vivo formation of highly carcinogenic N-nitroso compounds (5, 11). In tumorigenesis experiments, ascorbate inhibited lung adenoma induction in A strain mice by nitrite and amines (6, 7), and transplacental induction of neurogenic tumors in rats and hamsters by ethylurea and nitrite (8, 9). Studies on tumor production in rats showed that massive doses of ascorbate protected rats against liver tumor production by aminopyrine and sodium nitrite (10). Besides being useful in the blockade of the nitrosation reaction, high dose ascorbate treatment can be useful in the inhibition of tumor induction and growth in that it serves to cause a significant increase in the collagen content of the animal's tissues.