[Evaluation of the advantage of determination of urinary pseudouridine for the early detection of a malignant transformation process].

The catabolism of tRNA gives rise to modified nucleosides, among which pseudouridine, which are excreted in urine. An increased cell turnover is associated with an enhanced excretion of these products. Some authors have also reported an increased urinary excretion of pseudouridine in asbestos workers without clinical signs of malignancy. In two experimental models of carcinogenesis (i.e. injection of Lewis carcinoma cells in C57/B1C mice and oral administration of 7,12 dimethyl-benz(a)anthracene in female Sprague-Dawley rats), we have confirmed that the occurrence of the tumor is associated with an increased urinary excretion of pseudouridine. This metabolic change, however, does not precede the detection of the tumor. In control human subject, no sex and age effect was found in the urinary concentration of pseudouridine. Patients with a malignant disease excrete an enhanced amount of pseudouridine. A pilot study among workers exposed to polycyclic aromatic hydrocarbons in a coke oven did not reveal any change in the urinary concentration of pseudouridine.