[Metallothionein expression as a marker of therapeutic sensitivity in the early stages of testicular cancer].

Data concerning the involvement of elevated metallothionein (MT) expression in drug resistance are obviously scattered and contrasting. The presence of the MT gene product protein was screened in 51 untreated human germ cell testicular tumours, furthermore a relationship between MT expression and clinical resistance was investigated. Using monoclonal antibody and immunoenzyme staining elevated MT level could be demonstrated in nuclei and cytoplasm of both seminomas and non seminomatous germ cell testis tumours. Thirty-one tumours (61%) showed extensive, 15 (29%) focal positive staining. In contrast teratomas expressed this antigen negatively or scarcely. The highest level of MT was stated in early stages (I, IIA) compared with progressed stages (IIB, III) (p = 0.0004). Between the high level of MT and clinical resistance a converse correlation could be shown because the resistant tumours expressed no or low, while the sensitive tumours significantly high level of MT protein which can be used as an useful marker to identify patient subgroups sensitive to anticancer therapy, at least in testis tumours.