Metallothioneins in human kidneys and associated tumors

Human kidneys and their associated tumors (nonneoplastic kidney tissues fro m patients with a transitional cell carcinoma or an adenocarcinoma and the adenocarcinomas themselves) were evaluated for their Zn, Cd, and Cu content s as well as for their metallothionein (MT) level. The total Cd content was correlated with the MT content, and both values were significantly decreas ed in the adenocarcinomas in comparison with the other tissues. After extra ction and separation by anion-exchange chromatography, MT-0 was identified in the nonneoplastic tissues from both the adenocarcinomas as well as the t ransitional cell carcinomas. Since until now MT-0 protein was only found in human fetal liver and in Zn-stimulated human monocytes, a possible role fo r this isoform as an oncofetal marker is hypothesized. Separation of the is oforms of MT by reversed-phase high-performance liquid chromatography and s equence analysis showed besides MT-1e and MT-1l the isoform-MT-1g, which is not expressed in the healthy kidney, and MT-1k, an isoform which is not ye t demonstrated in renal tissues. We conclude that the expression profile of the MT isoforms in the kidney changes due to the presence of a tumor. Copy right (C) 1999 S. Karger AG, Basel.