Porphyrins in urine after administration of 5-aminolevulinic acid as a potential tumor marker

Abstract

Tumor markers are commonly used for cancer screening and as indicators of therapeutic effects. Certain types of tumor have been known to produce a variety of porphyrins after 5-aminolevulinic acid (ALA) administration. In this study, porphyrins in tumor-bearing mouse urine were analyzed after oral administration of ALA in order to identify new tumor markers excreted in the urine. Porphyrin concentrations in the urine of tumor-bearing mice were measured after administration of 1.0mg of ALA (approximately 50mgkg(-1)). Porphyrin concentrations in the urine of tumor-bearing mice increased after administration of ALA. HPLC analysis of the urine revealed the existence of uroporphyrin (UP) and coproporphyrin (CP) in the urine of ALA-treated tumor-bearing mice. Furthermore, at 3h after ALA administration, UP concentrations in the urine of tumor-bearing mice significantly increased compared to those in the urine of normal mice. These results suggest that UP as a precursor of heme detected in the urine of tumor-bearing mice after ALA administration is a potential marker of tumor development.