Synthesis of alpha-fetoprotein and some other serum proteins in testicular tumors.

Serum levels of alpha-fetoprotein were determined in 33 patients with testicular germ cell tumors and were normal in 11 patients with seminoma and in one patient with matured teratoma; high levels were observed in 19 of 21 patients with embryonal carcinoma, teratocarcinoma, or a mixed type of these germ cell tumors. Tissues from the testicular germ cell tumors were cultivated with 14C-labeled leucine. After incubation, the culture media were subjected to immunoelectrophoretic and autoradiographic analyses. The results were: (i) Radioactive alpha-fetoprotein, albumin, transferrin, and alpha1-globulin appeared in the culture media of embryonal carcinomas obtained from two infants. (ii) Radioactive albumin and alpha1-globulin appeared in the culture media of a mixed type tumor metastasized from testis to retroperitoneal region. (iii) No such radioactive proteins appeared in the culture media of primary seminomas.