Compounds that prevent the development

In addition to the regression of established tumors, a number of retinoids show apparent inhibition of the chemical induction of the bladder and other epithelial tumors in experimental animals. The effect is not in fact inhibition of carcinogenesis, but rather a lengthening of the latent period between the initiation step of carcinogenesis and the development of mmors. Although perhaps not as exciting as compounds that prevent the development of cancers, such a delaying action may be usefitl. If the results can be scaled from... 

Milk fat contains several compounds that have demonstrated anticancer activity in animal models. The more important ones are rumenic acid, a potent inhibitor of mammary tumorigenesis, sphingomyelin and other sphingolipids that prevent the development of intestinal tumors and butyric acid, which prevents colon and mammary tumor development. Emerging evidence suggests that milk fat can prevent intestinal infections, particularly in children, prevent allergic disorders, such as asthma and improve the level of long-chain co-3 polyunsaturated fatty acids in blood. 

It has been observed that the majority of remedies for preventing the development of flash lead to an increase of smoke (e.g. potassium salts give white smoke, aromatic nitro compounds give black-grey smoke due to the presence of unburnt carbon). Nitroguanidine is the only additive that does not appreciably increase smokiness. The burning of blackpowder in the primer produces an insignificant amount of smoke. 

As illustrated in Fig. 19, 95% of control animals developed palpable mammary tumors by 279 days after DMBA administration. Treatment with DHEA or EM-800 partially prevented the development of DMBA-induced mammary carcinoma, the incidence being thus reduced to 57% (p<. 01) or 38% (p<. 01), respectively. Interestingly, combination of the two compounds led to a significantly higher inhibitory effect than those achieved by each compound alone (p <. 01 versus DHEA or EM-800 alone). In fact, the only two tumors that developed in the group of animals treated with both compounds disappeared before the end of the experiment. 

---