Pterin 6 aldehyde, a cancer cell catabolite: identification and application in diagnosis and treatment of human cancer

Active folic degradation with the formation of pterin 6 aldehyde is a previously undescribed characteristic of cancer cells in tissue culture. Neither normal adult epithelial and fibroblastic cells nor human amniotic cells nor mouse embryonic fibroblasts degrade folic acid to a measurable degree. Twenty nine patients whose diagnoses were not revealed until after the test of their first morning urine for pterin 6 aldehyde was completed were studied for the presence or absence of pterin 6 aldehyde by thin layer chromatography. Pterin 6 aldehyde was found in the urine at about 300 nmol/ml or greater only in those 13 patients with a tissue diagnosis of cancer. When the cancer was totally resected, the pterin 6 aldehyde was no longer found in the urine postoperatively. Pterin 6 aldehyde is not found in the urine of healthy patients at this level of detection unless their diets are supplemented with folic acid.