Immunohistochemical localization of metallothionein in human testicular embryonal carcinoma cells.

The presence of high levels of metallothionein (MT) in developing mammalian cells is well documented. It has been suggested that the developmental profile and gene expression of MT is similar to that of the so-called oncodevelopmental gene products such as a-fetoprotein. In this study tissue sections of nine human embryonal carcinomas of the testis were tested by means of the avidin-biotin peroxidase complex for the presence of MT. The antigen was localized in variable amounts in the cytoplasm and nucleus in tumour cells in all cases. There was evidence that immunoreactivity was related to the histological growth pattern of tumour cells. These findings suggest that MT may be considered an oncodevelopmental product which could be useful as a tumour marker. In addition, the histology of these tumours might predict MT expression; this may prove of value in testing the hypothesis of MT-related emergence of drug-resistant cell lines in the course of treatment of tumours with metal-containing chemotherapeutic agents.