Effect of Orotic Acid on the Metastasis of Mammary Tumors in Mice.

In the course of studying the effect of nucleic acid precursors on viral carcinogenesis it was observed that an increased number of métastasesdeveloped in the lungs of orotic acid-treated mice with spontaneous mammary tumors. Further evidence that orotic acid increases the establishment of lung métastaseswas noted when orotic acidtreated C3H/HeN mice given injections intravenously of a cell suspension of mammary tumor cells were found to have significantly more lung métastasesthan control mice which received only the intravenous tumor cell injection.